JP2008260117A - Leg-wheel type robot and leg-wheel device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a leg-wheel type robot suitable for saving on energy consumption required for movement, and also to provide a leg-wheel device. <P>SOLUTION: The leg-wheel type robot 100 is furnished with: a base body 10; leg parts 12 connected to the base body 10 with freedom and constituted including the leg-wheel device 11; wheels 20 integrally provided with a leg driving mechanism part 16 forming a hip joint part of the leg parts 12; a joint motor 40 to give motive power to drive the leg parts 12; and a wheel motor 50 provided in the neighborhood of the wheels 20 and to give motive power to drive the wheels 20. Supply of driving electric power to the joint motor 40 is cut off in moving control using only the wheels 20 to carry out by controlling of the wheel motor 50, and supply of driving electric power to the wheel motor 50 is cut off, in a moving control using only the leg parts 12 to carry out by controlling of the joint motor 40. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a leg wheel type robot that can move over a step, and more particularly to a leg wheel type robot and a leg wheel device that are suitable for saving energy consumption for movement.

  The moving mechanism of the robot is classified into a wheel type, a crawler type, a leg type, or a combination thereof. In general, a wheel type robot has a problem of high mobility on a flat ground but low adaptability to a step. Crawler type robots are suitable for rough terrain, and can be overcome if there are a few steps. However, because they cannot actively move the center of gravity, they are less adaptable to steep stairs and are more mobile on flat ground than wheel type robots. There is a problem that it is low. In addition, the legged robot has the best adaptability to the stairs, but has the problem of extremely low mobility on flat ground.

In order to solve the problems of the wheel type, the crawler type and the leg type, a leg wheel type robot combining the leg type and the wheel type has been proposed. As leg-wheel type robots, for example, techniques described in Patent Literature 1 and Non-Patent Literature 1 are known.
A leg-wheel separated robot described in Patent Literature 1 includes a body, a pair of wheels rotatably provided on the body, a pair of front legs that are provided on the body, and that can be turned in a horizontal direction and a vertical direction. A pair of rear legs that can be turned in a horizontal direction and a vertical direction, an actuator that drives each wheel, an actuator that drives each front leg and each rear leg, and a controller that controls the operation of the actuator. Yes. The controller can select any one of a leg mode with a front leg and a rear leg, a wheel mode with a pair of wheels, and a leg wheel mode with a pair of wheels, a front leg and a rear leg.

In addition, the leg-wheel type robot described in Non-Patent Document 1 includes a mechanism for driving the wheel, but does not include a motor, and moves using a wheel by moving like sliding on a skate. is there.
JP 2006-315587 A Hirose Shigeo, Takeuchi Hiroki; Laura Walker: Proposal of a new leg-wheel hybrid moving body, Journal of the Japan Society of Mechanical Engineers (C), 62, 599, pp. 222-248 (1996)

However, in the prior art of the above-mentioned Patent Document 1, when traveling in the wheel mode, the motor is rotated to drive the wheel, and the other joints hold the motor at a certain angle. Even when not in use, current must continue to flow through the motor.
Further, in the prior art of Non-Patent Document 1, in order to reduce the weight of the foot and reduce the energy consumption, a special movement that slides on a skate without a motor for driving the wheels is provided. By doing so, traveling by wheel is realized, but during wheel traveling, current must be continuously supplied to the motors of the joints in order to maintain the posture.

  Therefore, the present invention has been made paying attention to such an unsolved problem of the conventional technology, and a leg wheel type robot and a leg wheel device suitable for saving energy consumption for movement are provided. It is intended to provide.

  [Invention 1] In order to achieve the above object, a leg-wheel type robot according to Invention 1 is provided with a base, a plurality of legs supported on the base via joints, and rotatably provided on each leg. And at least one of the leg and the wheel according to the environment, the control unit for controlling the actuator, and an actuator for applying power for driving the leg and the wheel. A leg-wheel type robot that moves according to the above, wherein the wheel is provided at a hip joint portion formed on an end side supported by the base of the leg portion, and an actuator for driving the wheel is provided in the vicinity of the wheel. The control means performs control to reduce the amount of drive power to be supplied to an actuator that is not used for the movement among the actuators that drive the legs and the wheels. And wherein the door.

With such a configuration, a wheel is provided in the vicinity of the base body, and an actuator for driving the wheel is provided in the vicinity of the wheel, so that the position of the center of gravity can be lowered and the conventional leg tip is provided. The inertia (inertial force) of the leg tip portion can be reduced as compared with the configuration in which the wheel is provided on the leg.
Also, when moving, actuators that are not used by the control means when traveling using only wheels, traveling using only a part of the wheels, walking using only the legs, etc. Since control (for example, control to cut off the supply of current) can be performed so as to reduce the amount of power supplied to the battery, energy consumption for movement can be reduced as compared with the conventional case.

Here, the above-mentioned “leg part” is composed of one link having only the hip joint part as a joint for giving a degree of freedom, and a structure in which a plurality of links are connected via joints (including the hip joint part). And so on. The same applies to the leg-wheel device of the eighth aspect and the leg-wheel type robot of the tenth aspect.
The “hip joint” is composed of one or a plurality of joints that give the legs freedom, for example, a joint that rotates the legs around an axis perpendicular to the bottom surface of the base, It consists of a joint that rotates the leg around an axis perpendicular to the vertical axis. The same applies to the leg-wheel device of the eighth aspect and the leg-wheel type robot of the tenth aspect.

[Invention 2] Furthermore, the leg-wheel type robot of Invention 2 is the leg-wheel type robot of Invention 1, wherein the actuator includes a first actuator that drives the leg and a second actuator that drives the wheel. It prepares for.
If it is such a structure, the 1st actuator which drives a leg part and the 2nd actuator which drives a wheel can be controlled independently by a control means.

[Invention 3] Further, the leg wheel type robot of the invention 3 is the leg wheel type robot of the invention 2, wherein when the control means moves using only the wheels, the plurality of leg portions are attached to the wheels. The first actuator is controlled so as to move and hold at a position above the ground plane.
With such a configuration, when the movement is performed with only the wheel, the leg is moved and held at a position above the ground contact surface of the wheel, thus preventing the leg from being obstructed by the wheel. be able to. Moreover, since the situation of moving by dragging the leg portion can be avoided reliably, the leg portion can be prevented from being damaged.

[Invention 4] Further, the leg wheel type robot of the invention 4 is the leg wheel type robot of the invention 3, wherein the control means moves the plurality of legs to a position above the ground contact surface of the wheel. Control is performed to cut off the supply of drive power to the first actuator while the vehicle is moving only with wheels.
In such a configuration, when the plurality of legs are moved only to the wheel after being moved to a position above the ground contact surface of the wheel, the drive power to the first actuator is controlled by the control means. Therefore, the energy consumption required when only the wheel is moved can be reduced as compared with the conventional case.

[Invention 5] Further, the leg-wheel type robot according to Invention 5 is the leg-wheel type robot according to Invention 3, wherein the control means moves the plurality of legs to a position above the ground contact surface of the wheel. While moving only with wheels, the first actuator is controlled so as to supply a minimum amount of driving power necessary for maintaining the posture of the upper leg portion. And
With such a configuration, only the driving power that cancels the rotational force generated by the weight of the leg after moving to a position above the wheel ground contact surface is supplied to each first actuator. It is possible to save energy consumption when moving only the wheel.

[Invention 6] Further, the leg-wheel type robot of the invention 6 is the leg-wheel type robot of the invention 3, wherein the control means drives the second actuator while moving using only the leg portion. Control is performed to cut off the supply of power.
With such a configuration, the power supply to the second actuator can be cut off during movement using only the leg portion, so that energy consumption required when moving only the leg portion can be reduced compared to the conventional case. can do.

[Invention 7] Further, the leg-wheel type robot according to Invention 7 is the leg-wheel type robot according to Invention 3, wherein the control means drives the leg part to get over the obstacle, and the leg part gets over the obstacle. The first actuator is controlled so that the wheel provided on the vehicle contacts the obstacle.
With such a configuration, when overcoming obstacles such as steps on the moving path, the wheels can be contacted in addition to the contact with the legs, so the number of points supporting the own weight is increased more than when only the legs are used. In addition to being able to get over the steps with stable walking, it is possible to use the wheels to get over the height steps that could not be overcome with the legs alone.

  [Invention 8] On the other hand, in order to achieve the above object, the leg wheel device of Invention 8 is provided with a leg portion supported via a joint with respect to a base body of a leg wheel type robot, and rotatably provided on the leg portion. A leg wheel device that moves the leg wheel type robot by driving at least one of the leg portion and the wheel, and the leg portion and an actuator that gives power to drive the wheel. The wheel is configured to be provided in a hip joint portion configured on an end side supported by the base body of the leg portion, and an actuator for driving the wheel is configured to be provided in the vicinity of the wheel. .

  With such a configuration, the wheel can be provided in the vicinity of the base body, and the actuator for driving the wheel can be provided in the vicinity of the wheel, so that the position of the center of gravity of the leg wheel type robot can be lowered. At the same time, the inertia (inertial force) of the leg tip portion can be reduced as compared with the configuration in which the wheel is provided on the conventional leg tip.

[Invention 9] Further, the leg wheel device of Invention 9 is characterized in that, in the leg wheel device of Invention 8, the actuator for rotationally driving the wheel is provided independently of the actuator for driving the leg portion.
With such a configuration, the actuator for driving the leg portion and the actuator for driving the wheel can be controlled independently.

[Invention 10] On the other hand, in order to achieve the above object, the leg-wheel type robot of Invention 10 includes the leg-wheel device described in Invention 8 or Invention 9.
If it is such a structure, the effect | action equivalent to the leg wheel apparatus of the invention 8 or 9 will be acquired.

[Invention 11] Furthermore, the leg-wheel type robot according to invention 11 is the leg-wheel type robot according to any one of inventions 1 to 7 and 10, wherein the leg portion of the leg-wheel type robot depends on the environment when traveling with only the wheel. A leg posture changing means for changing the posture is provided.
With such a configuration, for example, the position of the center of gravity can be changed by changing the posture of the leg portion such as extending the front leg forward while the vehicle is traveling on a slope.

  [Invention 12] On the other hand, in order to achieve the above object, the object recognition apparatus of the invention 12 is an object recognition apparatus for recognizing a surface or a boundary of a surface on an object, and measures a distance to a measurement point on the object. A distance measuring sensor, a scanning means for scanning the distance measuring sensor, a measurement result acquiring means for acquiring a measurement result of the distance measuring sensor for the measurement points that can be measured in a scanning range of the scanning means, and the measurement result A coordinate conversion means for converting the measurement result acquired by the acquisition means into coordinates of an orthogonal coordinate system; and a line segment in the orthogonal coordinate system by Hough conversion based on the coordinates of at least two of the measurement points converted by the coordinate conversion means. And a recognition unit for recognizing a surface on the object or a boundary of the surface based on the line segment detected by the line segment detection unit.

With such a configuration, the distance measuring sensor can be scanned by the scanning unit. Therefore, at least the planar shape of the object can be grasped. Then, the measurement result acquisition unit acquires the measurement result of the distance measuring sensor for the measurement points that can be measured in the scanning range of the scanning unit, and the coordinate conversion unit converts the acquired measurement result into the coordinates of the orthogonal coordinate system. .
Next, a line segment in the orthogonal coordinate system is detected by the Hough transform based on the transformed coordinates of at least two measurement points.

As another method for detecting a line segment based on a plurality of measurement points, a least square method is known.
However, since the least square method detects a line segment by tracing each measurement point, a line segment that does not follow the surface on the object may be detected in a region where the measurement resolution is low. On the other hand, in the Hough transform, it is difficult to be affected by the measurement resolution, and a line segment relatively along the surface on the object can be detected even if the measurement resolution includes a low region.

  In the least-square method, line segments are detected by tracing each measurement point. Therefore, if measurement results vary due to the gloss of the measurement surface, etc. An area (hereinafter referred to as an error area) is detected as an oblique line segment, which is actually a flat line segment. On the other hand, the Hough transform is not easily affected by variations, and if the number of variations is small, the error region and the regions on both sides thereof can be detected as flat line segments.

  Further, the least square method has a problem as to whether to recognize a region from where to where is one continuous surface. In this case, for example, it is conceivable to recognize a point where the slope of the detected line segment changes abruptly as the boundary of the continuous surface. However, with this recognition method, the error region and the regions on both sides of the error region are actually 1 Two continuous areas are recognized as separate continuous areas. On the other hand, the Hough transform is not easily affected by variation, and if the number of variations is small, the error region and the regions on both sides thereof can be detected as one flat line segment.

When the line segment is detected by the Hough transform, the recognition unit recognizes the surface or the boundary of the surface on the object based on the detected line segment. Accordingly, it is possible to obtain a recognition result suitable for posture control of a robot that requires complicated posture control, such as a legged robot or a leg-wheel type robot.
Here, the scanning means may have any configuration as long as it scans the distance measuring sensor. For example, the scanning means scans the distance measuring sensor one-dimensionally so that the locus of the measurement points forms a line. Alternatively, the distance measuring sensor may be scanned two-dimensionally so that the locus of the measurement points forms a plane. In the former case, the planar shape of the object can be grasped, and in the latter case, the three-dimensional shape of the object can be grasped. The same applies to the object recognition apparatuses according to inventions 13 and 18.

Moreover, as a scanning means, the following structure is employable, for example.
(1) Rotating mechanism The rotating mechanism is configured by rotating means for rotating the distance measuring sensor around at least one scanning axis that forms a predetermined angle with respect to the measuring direction of the distance measuring sensor.
(2) Moving mechanism The moving mechanism is configured by moving means for moving the distance measuring sensor in at least one scanning direction different from the measuring direction of the distance measuring sensor. The moving means may move the distance measuring sensor along a path including a path extending in the scanning direction. The same applies to the object recognition apparatuses according to inventions 13 and 18.

  [Invention 13] The object recognition apparatus according to Invention 13 is an object recognition apparatus for recognizing a surface or a boundary of a surface on an object, the distance measuring sensor for measuring a distance to a measurement point on the object, and the measurement. Scanning means for scanning the distance sensor, measurement result acquiring means for acquiring the measurement results of the distance measuring sensor for the measurement points that can be measured in the scanning range of the scanning means, and measurement results acquired by the measurement result acquiring means Coordinate conversion means for converting into coordinates in an orthogonal coordinate system, inter-measurement point interpolation means for interpolating between the measurement points converted by the coordinate conversion means, and points on the line obtained by the inter-measurement point interpolation means Line segment detection means for detecting a line segment in the orthogonal coordinate system by Hough transform based on the coordinates of the object, and recognition means for recognizing a surface or a boundary of the surface on the object based on the line segment detected by the line segment detection means With.

With such a configuration, the distance measuring sensor can be scanned by the scanning unit. Therefore, at least the planar shape of the object can be grasped. Then, the measurement result acquisition unit acquires the measurement result of the distance measuring sensor for the measurement points that can be measured in the scanning range of the scanning unit, and the coordinate conversion unit converts the acquired measurement result into the coordinates of the orthogonal coordinate system. .
Next, the inter-measurement point interpolation means interpolates between the converted measurement points, and the line segment detection means detects the line segment in the orthogonal coordinate system by Hough transform based on the coordinates of the point on the obtained line. The

As another method for detecting a line segment based on a plurality of measurement points, a least square method is known.
However, since the least square method detects a line segment by tracing each measurement point, a line segment that does not follow the surface on the object may be detected in a region where the measurement resolution is low. On the other hand, in the Hough transform, it is difficult to be affected by the measurement resolution, and a line segment relatively along the surface on the object can be detected even if the measurement resolution includes a low region.

  In addition, in the least square method, the line segment is detected by tracing each measurement point. Therefore, when the measurement result varies due to the influence of the gloss of the measurement surface, the error area is actually a flat line segment. However, it is detected as an oblique line segment. On the other hand, the Hough transform is not easily affected by variations, and if the number of variations is small, the error region and the regions on both sides thereof can be detected as flat line segments.

  Further, the least square method has a problem as to whether to recognize a region from where to where is one continuous surface. In this case, for example, it is conceivable to recognize a point where the slope of the detected line segment changes abruptly as the boundary of the continuous surface. However, with this recognition method, the error region and the regions on both sides of the error region are actually 1 Two continuous areas are recognized as separate continuous areas. On the other hand, the Hough transform is not easily affected by variation, and if the number of variations is small, the error region and the regions on both sides thereof can be detected as one flat line segment.

When the line segment is detected by the Hough transform, the recognition unit recognizes the surface or the boundary of the surface on the object based on the detected line segment. Accordingly, it is possible to obtain a recognition result suitable for posture control of a robot that requires complicated posture control, such as a legged robot or a leg-wheel type robot.
Here, the interpolation includes connecting the measurement points with a line and approximating the measurement points with a line. The measurement points do not necessarily have to be located on the line, and adjacent measurement points are not necessarily included. It is not necessary to target points. Hereinafter, the same applies to the object recognition device of the invention 20 and the object recognition method of the invention 29.
The line includes a straight line, a line segment, a multi-order curve, and other curves. Hereinafter, the same applies to the object recognition device of the invention 20 and the object recognition method of the invention 29.

[Invention 14] The object recognition apparatus according to Invention 14 is the object recognition apparatus according to any one of Inventions 12 and 13, wherein the recognition means is based on the coordinates of the end points of the line segment detected by the line segment detection means. Recognize the boundary of the surface on the object.
With such a configuration, the recognition means recognizes the boundary of the surface on the object based on the coordinates of the end points of the detected line segment.

  [Invention 15] Furthermore, the object recognition device of Invention 15 is the object recognition device of any one of Inventions 12 to 14, wherein the scanning means measures the measurement in a first scanning direction different from the measurement direction of the distance measuring sensor. A first scanning unit that scans the distance sensor; and a second scanning unit that scans the distance measuring sensor in a second scanning direction different from the measurement direction and the first scanning direction. The measurement result of the distance measuring sensor is acquired for the measurement points that can be measured in the scanning range of the first scanning means and the second scanning means.

  With this configuration, the first scanning unit can scan the distance measuring sensor in the first scanning direction, and the second scanning unit can scan the distance measuring sensor in the second scanning direction. Therefore, the three-dimensional shape of the object can be grasped. Then, the measurement result acquisition means acquires the measurement result of the distance measuring sensor for the measurement points that can be measured in the scanning range of the first scanning means and the second scanning means.

Here, as the first scanning unit and the second scanning unit, for example, the following configuration can be adopted.
(1) Rotation mechanism First rotation means for rotating the distance measuring sensor around a first scanning axis that forms a predetermined angle with respect to the measurement direction of the distance measuring sensor, and the measurement direction and the first scanning axis. And a second rotating means for rotating the distance measuring sensor around a second scanning axis forming a predetermined angle.
(2) Moving mechanism First moving means for moving the distance measuring sensor in a first scanning direction different from the measuring direction of the distance measuring sensor, and a second scanning direction different from the measuring direction and the first scanning direction. It comprises a second moving means for moving the distance measuring sensor. The first moving unit may move the distance measuring sensor along a first path including a path extending in the first scanning direction, and the second moving unit extends in the second scanning direction. The distance measuring sensor may be moved along a second route including a route to be performed. The same applies to (3) and (4) below.

(3) Combination of rotating mechanism and moving mechanism Rotating means for rotating the distance measuring sensor around a scanning axis forming a predetermined angle with respect to the measuring direction of the distance measuring sensor, and scanning different from the axial direction of the scanning axis And a moving means for moving the distance measuring sensor in the direction.
(4) A combination of a moving mechanism and a rotating mechanism The moving means for moving the distance measuring sensor in a scanning direction different from the measuring direction of the distance measuring sensor, and the scanning axis about a predetermined angle with respect to the scanning direction It is the structure which consists of a rotation means to rotate a ranging sensor. The same applies to the object recognition apparatus of the invention 22 below.

[Invention 16] Furthermore, the object recognition device of Invention 16 is the object recognition device of Invention 15, wherein the recognition means recognizes a surface on the object based on the coordinates of the end points of the line segment detected by the line segment detection means. To do.
With such a configuration, the surface on the object is recognized by the recognition unit based on the coordinates of the end points of the detected line segment.

  [Invention 17] The object recognition apparatus according to Invention 17 is the object recognition apparatus according to any one of Inventions 15 and 16, in which the first scanning means has a first scanning axis that forms a predetermined angle with respect to the measurement direction. A first rotating means for rotating the distance measuring sensor around, the second scanning means being configured to rotate the distance measuring sensor around a second scanning axis that forms a predetermined angle with respect to the measuring direction and the first scanning axis; The measurement result acquisition means outputs the measurement result of the distance measurement sensor for each predetermined unit angle of the first rotation means while rotating the distance measurement sensor by the first rotation means. A predetermined unit angle of the first rotating means is obtained by performing a second scan in which the first scanning to be acquired is performed at predetermined unit angles of the second rotating means while rotating the distance measuring sensor by the second rotating means. Your And obtaining the measurement results for each predetermined unit angle of the second rotation means.

  With such a configuration, the distance measuring sensor can be rotated around the first scanning axis by the first rotating means, and the distance measuring sensor can be rotated around the second scanning axis by the second rotating means. Therefore, the three-dimensional shape of the object can be grasped. Then, the second scanning is performed by the measurement result acquisition unit, whereby measurement results for each predetermined unit angle of the first rotation unit and for each predetermined unit angle of the second rotation unit are acquired. In the second scanning, the first scanning is performed for each predetermined unit angle of the second rotating means while the distance measuring sensor is rotated by the second rotating means. In the first scan, a measurement result is acquired for each predetermined unit angle of the first rotating means while rotating the distance measuring sensor by the first rotating means.

  [Invention 18] The object recognition apparatus of the invention 18 is an object recognition apparatus for recognizing a surface or a boundary of a surface on an object, the distance measuring sensor for measuring a distance to a measurement point on the object, and the measurement. A scanning unit that scans the distance sensor, a measurement result acquisition unit that acquires a measurement result of the distance measuring sensor for the measurement point that can be measured in a scanning range of the scanning unit, and a measurement result acquired by the measurement result acquisition unit. A first feature detecting unit for detecting a feature on the object based on the image, an imaging unit for capturing an image including the measurement point that can be measured in a scanning range of the scanning unit, and an object based on the image captured by the imaging unit. Second feature detection means for detecting the upper feature, and recognition means for recognizing a surface or a boundary of the surface on the object based on detection results of the first feature detection means and the second feature detection means.

With such a configuration, the distance measuring sensor can be scanned by the scanning unit. Therefore, at least the planar shape of the object can be grasped. Then, the measurement result acquisition means acquires the measurement result of the distance measuring sensor for the measurement points that can be measured in the scanning range of the scanning means, and the first feature detection means determines the feature on the object based on the acquired measurement result. Detected.
In addition, an image including a measurement point that can be measured within the scanning range of the scanning unit is captured by the imaging unit, and a feature on the object is detected based on the captured image by the second feature detection unit.

Then, the recognition unit recognizes the surface or the boundary of the surface on the object based on the detection results of the first feature detection unit and the second feature detection unit.
Here, the features on the object include, for example, points indicating features on the object, straight lines, line segments, multi-order curves, circles, ellipses and other curves, planes, curved surfaces and other surfaces, cubes, spheres and other three-dimensional shapes. Features are included. The same applies to the object recognition method of the invention 30 below.

  [Invention 19] Further, the object recognition device of Invention 19 is the object recognition device of Invention 18, wherein the first feature detection means is a coordinate for converting the measurement result acquired by the measurement result acquisition means into coordinates of an orthogonal coordinate system. Conversion means; and line segment detection means for detecting line segments in the orthogonal coordinate system by Hough transform based on the coordinates of at least two measurement points converted by the coordinate conversion means; and the recognition means, Based on the line segment detected by the line segment detection means and the detection result of the second feature detection means, the surface on the object or the boundary of the surface is recognized.

If it is such a structure, the acquired measurement result will be converted into the coordinate of a rectangular coordinate system by a coordinate conversion means.
Then, a line segment in the orthogonal coordinate system is detected by the Hough transform based on the transformed coordinates of at least two measurement points.
As another method for detecting a line segment based on a plurality of measurement points, a least square method is known.

However, since the least square method detects a line segment by tracing each measurement point, a line segment that does not follow the surface on the object may be detected in a region where the measurement resolution is low. On the other hand, in the Hough transform, it is difficult to be affected by the measurement resolution, and a line segment relatively along the surface on the object can be detected even if the measurement resolution includes a low region.
In addition, in the least square method, the line segment is detected by tracing each measurement point. Therefore, when the measurement result varies due to the influence of the gloss of the measurement surface, the error area is actually a flat line segment. However, it is detected as an oblique line segment. On the other hand, the Hough transform is not easily affected by variations, and if the number of variations is small, the error region and the regions on both sides thereof can be detected as flat line segments.

  Further, the least square method has a problem as to whether to recognize a region from where to where is one continuous surface. In this case, for example, it is conceivable to recognize a point where the slope of the detected line segment changes abruptly as the boundary of the continuous surface. However, with this recognition method, the error region and the regions on both sides of the error region are actually 1 Two continuous areas are recognized as separate continuous areas. On the other hand, the Hough transform is not easily affected by variation, and if the number of variations is small, the error region and the regions on both sides thereof can be detected as one flat line segment.

  When the line segment is detected by the Hough transform, the recognition unit recognizes the surface or the boundary of the surface on the object based on the detected line segment and the detection result of the second feature detection unit. Therefore, the technique of Non-Patent Document 1 can generate only simple map information for movement control of a crawler type robot that does not require complicated posture control. Since at least the planar shape of an object can be grasped as a boundary, a recognition result suitable for posture control of a robot that requires complicated posture control such as a legged robot or a leg-wheel type robot can be obtained. .

  [Invention 20] Furthermore, the object recognition device of Invention 20 is the object recognition device of Invention 18, wherein the first feature detection means is a coordinate for converting the measurement result acquired by the measurement result acquisition means into coordinates of an orthogonal coordinate system. A conversion means, an inter-measurement point interpolation means for interpolating between the measurement points converted by the coordinate conversion means, and the Hough transform based on the coordinates of the points on the line obtained by the inter-measurement point interpolation means. A line segment detecting means for detecting a line segment in an orthogonal coordinate system, wherein the recognizing means is a surface on the object based on the line segment detected by the line segment detecting means and the detection result of the second feature detecting means. Or recognize the boundary of the face.

If it is such a structure, the acquired measurement result will be converted into the coordinate of a rectangular coordinate system by a coordinate conversion means, and between the measured points will be interpolated by a line by the inter-measurement point interpolation means.
Then, a line segment in the orthogonal coordinate system is detected by the Hough transform based on the coordinates of the obtained point on the line. It should be noted that there are advantages similar to those described above over the least square method.
When the line segment is detected by the Hough transform, the recognition unit recognizes the surface or the boundary of the surface on the object based on the detected line segment and the detection result of the second feature detection unit. Therefore, as described above, it is possible to obtain a recognition result suitable for posture control of a robot that requires complicated posture control, such as a legged robot or a leg-wheel type robot.

  [Invention 21] Further, the object recognition device of Invention 21 is the object recognition device of Invention 18, wherein the first feature detection means is a coordinate for converting the measurement result acquired by the measurement result acquisition means into coordinates of an orthogonal coordinate system. Inclination calculation for calculating the inclination at the measurement point in the orthogonal coordinate system based on the coordinates of the measurement point and the coordinates of the measurement points in the vicinity thereof for each measurement point converted by the conversion means and the coordinate conversion means And an appearance frequency calculating means for calculating the appearance frequency of each inclination with respect to the total number of inclinations calculated by the inclination calculating means, and the recognition means is the appearance frequency calculated by the appearance frequency calculating means and the converted The surface on the object or the boundary of the surface is recognized based on the coordinates of each measurement point and the detection result of the second feature detection means.

  If it is such a structure, the acquired measurement result will be converted into the coordinate of a rectangular coordinate system by the coordinate conversion means, and the coordinates of the measurement point and its surroundings will be obtained for each converted measurement point by the inclination calculation means. The inclination at the measurement point in the orthogonal coordinate system is calculated based on the coordinates of the measurement points, and the appearance frequency calculating means calculates the appearance frequency of each inclination with respect to the calculated total number of inclinations.

  When the appearance frequency of each inclination is calculated, the recognition unit calculates the surface on the object or the boundary of the surface based on the calculated appearance frequency, the converted coordinates of each measurement point, and the detection result of the second feature detection unit. Is recognized. Therefore, as described above, it is possible to obtain a recognition result suitable for posture control of a robot that requires complicated posture control, such as a legged robot or a leg-wheel type robot.

  Here, the inclination calculation means, for example, approximates a regression line with respect to a plurality of measurement points by a known least square method, calculates an inclination from the regression line, or, in an orthogonal coordinate system, a plurality of continuous in one axial direction. Inclination is calculated using the difference value of the coordinates of the two measurement points at both ends of the measurement point and the difference value of the coordinates of the measurement points of the two ends of the plurality of measurement points continuous in the other axial direction. Can do.

  [Invention 22] The object recognition apparatus according to Invention 22 is the object recognition apparatus according to any one of Inventions 18 to 21, wherein the scanning means measures the measurement in a first scanning direction different from the measurement direction of the distance measuring sensor. A first scanning unit that scans the distance sensor; and a second scanning unit that scans the distance measuring sensor in a second scanning direction different from the measurement direction and the first scanning direction. The measurement result of the distance measuring sensor is acquired for the measurement points that can be measured in the scanning range of the first scanning means and the second scanning means.

  With this configuration, the first scanning unit can scan the distance measuring sensor in the first scanning direction, and the second scanning unit can scan the distance measuring sensor in the second scanning direction. Therefore, the three-dimensional shape of the object can be grasped. Then, the measurement result acquisition means acquires the measurement result of the distance measuring sensor for the measurement points that can be measured in the scanning range of the first scanning means and the second scanning means.

  [Invention 23] The object recognition apparatus according to Invention 23 is the object recognition apparatus according to Invention 22, wherein the first scanning means includes the distance measuring sensor around a first scanning axis that forms a predetermined angle with respect to the measurement direction. The second scanning means rotates the distance measuring sensor around a second scanning axis that forms a predetermined angle with respect to the measurement direction and the first scanning axis. The measurement result acquisition means performs a first scan for acquiring the measurement result of the distance measurement sensor for each predetermined unit angle of the first rotation means while rotating the distance measurement sensor by the first rotation means. By performing the second scanning performed at every predetermined unit angle of the second rotating means while rotating the distance measuring sensor by the second rotating means, the second rotation is performed at every predetermined unit angle of the first rotating means. hand Acquiring the measurement results for each predetermined unit angle.

  With such a configuration, the distance measuring sensor can be rotated around the first scanning axis by the first rotating means, and the distance measuring sensor can be rotated around the second scanning axis by the second rotating means. Therefore, the three-dimensional shape of the object can be grasped. Then, the second scanning is performed by the measurement result acquisition unit, whereby measurement results for each predetermined unit angle of the first rotation unit and for each predetermined unit angle of the second rotation unit are acquired. In the second scanning, the first scanning is performed for each predetermined unit angle of the second rotating means while the distance measuring sensor is rotated by the second rotating means. In the first scan, a measurement result is acquired for each predetermined unit angle of the first rotating means while rotating the distance measuring sensor by the first rotating means.

  [Invention 24] The object recognition apparatus according to Invention 24 is the object recognition apparatus according to any one of Inventions 18 to 21, further comprising a plurality of the distance measuring sensors and the scanning means, wherein each of the scanning means includes the scanning means. Are scanned in a first scanning direction different from the measurement direction of the distance measuring sensor, and each distance measuring sensor is scanned in a second scanning direction different from the measurement direction and the first scanning direction. Is arranged.

  With such a configuration, each scanning unit can scan each distance measuring sensor arranged in the second scanning direction in the first scanning direction. Therefore, the three-dimensional shape of the object can be grasped. And the measurement result of each ranging sensor is acquired by the measurement result acquisition means about the measurement point which can be measured in the scanning range of a scanning means.

  [Invention 25] Further, the object recognition device of Invention 25 is the object recognition device of any one of Inventions 18 to 24, wherein the first feature detection means is an object based on the measurement result acquired by the measurement result acquisition means. The upper feature point is detected, and the second feature detection unit includes an image line segment detection unit that detects a line segment from an image captured by the imaging unit, and the recognition unit is based on the imaging unit. In the coordinate system, the surface on the object or the boundary of the surface is recognized based on the positional relationship between the line segment detected by the image line segment detection unit and the feature point detected by the first feature detection unit.

If it is such a structure, the feature point on an object will be detected by the 1st feature detection means based on the acquired measurement result, and a line segment will be detected from the imaged image by the image line segment detection means. .
Then, the recognition unit recognizes the surface or the boundary of the surface on the object based on the positional relationship between the detected line segment and the detected feature point in the coordinate system based on the imaging unit.

  [Invention 26] Further, the object recognition device of Invention 26 is the object recognition device of Invention 25, wherein the recognition means calculates the line segment and the line segment for each line segment detected by the image line segment detection means. Corresponding to the feature points existing within a predetermined distance from the extended straight line, grouping the line segments associated with the same feature points, and based on the coordinates of the end points of the line segments belonging to the same group Recognize the upper face or face boundary.

  With such a configuration, the recognition means associates each detected line segment with the line segment and a feature point existing within a predetermined distance from the straight line obtained by extending the line segment, and the same feature The line segments associated with the points are grouped, and the surface on the object or the boundary of the surface is recognized based on the coordinates of the end points of the line segments belonging to the same group.

  [Invention 27] Furthermore, the object recognition device of Invention 27 is the object recognition device of any one of Inventions 25 and 26, wherein a plane composed of two predetermined axes in an orthogonal coordinate system with the distance measuring sensor as a reference, The distance measuring sensor and the imaging means are arranged so that a plane composed of two predetermined axes in an orthogonal coordinate system based on the imaging means is parallel.

  [Invention 28] On the other hand, in order to achieve the above object, the object recognition method of Invention 28 recognizes a surface or a boundary of a surface on an object using a distance measuring sensor that measures a distance to a measurement point on the object. An object recognition method, a scanning step of scanning the distance measuring sensor, a measurement result acquiring step of acquiring a measurement result of the distance measuring sensor for the measurement points that can be measured in a scanning range of the scanning step, and the measurement A coordinate conversion step for converting the measurement result acquired in the result acquisition step into a coordinate in the orthogonal coordinate system, and a line in the orthogonal coordinate system by Hough conversion based on the coordinates of the at least two measurement points converted in the coordinate conversion step. A line segment detecting step for detecting a segment, and a recognition step for recognizing a surface or a boundary of the surface on the object based on the line segment detected in the line segment detecting step.

  Here, the scanning step may be any method as long as it scans the distance measuring sensor. For example, the distance measuring sensor may be scanned one-dimensionally so that the locus of the measurement points forms a line. Alternatively, the distance measuring sensor may be scanned two-dimensionally so that the locus of the measurement points forms a plane. In the former case, the planar shape of the object can be grasped, and in the latter case, the three-dimensional shape of the object can be grasped. The same applies to the object recognition methods of the inventions 29 and 30 below.

  [Invention 29] Further, the object recognition method of the invention 29 is an object recognition method for recognizing a surface or a boundary of a surface on an object by using a distance measuring sensor for measuring a distance to a measurement point on the object. A scanning step for scanning the distance measuring sensor, a measurement result acquiring step for acquiring a measurement result of the distance measuring sensor for the measurement points that can be measured in the scanning range of the scanning step, and a measurement result acquired in the measurement result acquiring step On the line obtained by the coordinate conversion step for converting the coordinates into the coordinates of the orthogonal coordinate system, the inter-measurement point interpolation step for interpolating between the measurement points converted by the coordinate conversion step, and the inter-measurement point interpolation step A line segment detection step for detecting a line segment in the orthogonal coordinate system by Hough transform based on the coordinates of the point, and a surface on the object based on the line segment detected in the line segment detection step. And a recognition step recognizes the boundary of the surface.

  [Invention 30] The object recognition method of the invention 30 is an object recognition method for recognizing a surface or a boundary of a surface on an object using a distance measuring sensor for measuring a distance to a measurement point on the object. A scanning step for scanning the distance measuring sensor, a measurement result acquiring step for acquiring a measurement result of the distance measuring sensor for the measurement points that can be measured in the scanning range of the scanning step, and a measurement result acquired in the measurement result acquiring step A first feature detection step for detecting a feature on the object based on the image, an imaging step for capturing an image including the measurement point that can be measured in a scanning range of the scanning step, and an image captured in the imaging step A second feature detecting step for detecting a feature on the object; a surface on the object based on the detection results of the first feature detecting step and the second feature detecting step; The boundary surface and a recognizing step.

  As described above, according to the leg-wheel type robots of the first and second aspects of the invention, the center of gravity of the robot can be lowered, so that an effect that stable movement can be performed is obtained, and Since the inertia can be reduced, the effect that the leg tip can be moved at a higher speed than in the prior art can be obtained. In addition, since it is possible to reduce the amount of power supplied to the unused actuator, it is possible to reduce the amount of energy consumed for movement compared to the prior art.

  Further, according to the leg-wheel type robot of the invention 3, when the movement is performed only by the wheel, the leg can be moved and held at a position above the ground contact surface of the wheel, so that the leg is moved by the wheel. As a result, it is possible to prevent a situation in which the leg portion is prevented from being damaged, and the leg portion can be prevented from being damaged.

In addition, according to the leg-wheel type robots of the inventions 4 to 5, since the amount of driving power supplied to the first actuator can be reduced when moving with only the wheels, It is possible to reduce the amount of energy consumed when only moving.
In addition, according to the leg-wheel type robot of the sixth aspect of the invention, since the power supply to the second actuator can be cut off during movement using only the leg portion, it takes more time when only the leg portion is moved than in the prior art. The effect is that energy consumption can be saved.

  In addition, according to the leg-wheel type robot of the invention 7, when overcoming an obstacle such as a step on the moving path, the wheel can be brought into contact in addition to the contact of the leg, so that the weight of the robot is more than that of the leg alone. Since the number of points that support the vehicle can be increased, the effect of being able to get over the steps with stable walking can be obtained, and it is possible to use the wheels to get over the steps that could not be overcome with the legs alone. The effect that it can be obtained.

Moreover, according to the leg-wheel apparatus of invention 8-9, since the gravity center position of a leg-wheel-type robot can be made low, while being able to make a leg-wheel-type robot perform stable movement, it is acquired, Since the inertia of the leg tip of the leg-wheel type robot can be reduced, an effect that the leg tip can be moved at a higher speed than in the prior art can be obtained.
Further, according to the leg-wheel type robot of the tenth aspect, since the position of the center of gravity of the robot can be lowered, an effect that stable movement can be performed is obtained, and the inertia of the leg tip can be reduced. As a result, the effect of being able to move the leg tip at a higher speed than in the prior art can be obtained.

In addition, according to the leg-wheel type robot of the eleventh aspect of the present invention, it is possible to change the center of gravity by actively using the legs during wheel traveling, and to obtain an effect that the wheels can travel more stably.
On the other hand, according to the object recognition device of the invention 12, 13, 19 or 20, since at least the planar shape of the object can be grasped as a surface on the object or a boundary between the surfaces, a legged robot or a leg wheel type robot. As described above, it is possible to obtain a recognition result suitable for posture control of a robot that requires complicated posture control. In addition, because line segments are detected by Hough transform, when object recognition is performed using a two-dimensional distance measuring device using a distance measuring sensor, the possibility that the recognition accuracy will decrease due to a decrease in measurement resolution or variations in measurement results is reduced. The effect that it can do is also acquired.

Furthermore, according to the object recognition device of the thirteenth or twentieth aspect, since the line segment is detected based on the coordinates of the points on the line obtained by interpolating between the measurement points with the line, the measurement resolution is lowered or the measurement result is varied. Even if this occurs, it is possible to obtain a relatively accurate recognition result, and to further reduce the possibility that the recognition accuracy is lowered.
Further, according to the object recognition device of the fourteenth aspect of the present invention, an effect that the boundary of the surface on the object can be recognized relatively accurately is obtained.

Further, according to the object recognition device of the fifteenth aspect, since the three-dimensional shape of the object can be grasped as a surface on the object or a boundary between the surfaces, complicated posture control such as a legged robot or a leg wheel type robot can be performed. It is possible to obtain a recognition result more suitable for posture control of a robot that requires
Furthermore, according to the object recognition device of the sixteenth aspect, it is possible to obtain an effect that the surface on the object can be recognized relatively accurately.

Further, according to the object recognition device of the invention 17, since the rotation mechanism for rotating the distance measuring sensor is adopted, the space required for scanning is smaller than that of the moving mechanism, and the mechanism for scanning becomes simple. And the effect that a high-speed scanning is realizable is acquired.
Furthermore, according to the object recognition device of the eighteenth aspect, in addition to the distance measurement sensor, the feature on the object is detected using the imaging means of a different system, and the surface on the object is detected based on the two detection results. Alternatively, since the boundary of the surface is recognized, the shortcomings of the method using the distance measuring sensor can be compensated for by the method using the imaging means, and the recognition accuracy decreases when the object is recognized by the two-dimensional distance measuring device using the distance measuring sensor. The effect that it is possible to reduce the possibility of doing is obtained. In addition, since it is not necessary to increase the number of scans of the scanning means, the effect that the measurement time can be shortened is also obtained.

  Furthermore, according to the object recognition device of the invention 21, since at least a planar shape of an object can be grasped as a surface on the object or a boundary between surfaces, a complicated posture such as a legged robot or a legged wheel type robot can be obtained. An effect is obtained that a recognition result suitable for posture control of a robot that requires control can be obtained. In addition, since the surface on the object or the boundary of the surface is recognized based on the appearance frequency of the inclination at the measurement point and the coordinates of each measurement point, when the object recognition is performed by the two-dimensional distance measuring device using the distance measuring sensor. In addition, there is an effect that the possibility that the recognition accuracy is lowered can be further reduced.

Furthermore, according to the object recognition device of the invention 22 or 24, the three-dimensional shape of the object can be grasped as a surface on the object or a boundary between the surfaces. An effect is obtained that a recognition result more suitable for posture control of a robot that requires posture control can be obtained.
Further, according to the object recognition device of the invention 23, since the rotation mechanism for rotating the distance measuring sensor is adopted, the space required for scanning is smaller than that of the moving mechanism, and the mechanism for scanning becomes simple. And the effect that a high-speed scanning is realizable is acquired.

Furthermore, according to the object recognition device of the invention 25, the surface or the boundary of the surface on the object is recognized based on the positional relationship between the line segment detected from the image and the feature point detected from the measurement result of the distance measuring sensor. Therefore, an effect that the possibility that the recognition accuracy is lowered can be further reduced.
Further, according to the object recognition device of the invention 26, even if it is detected as a plurality of line segments from the captured image due to the influence of contrast or the like, it is actually measured by the distance measuring sensor. Based on the correspondence with the feature points detected from the results, multiple line segments are grouped as a single line segment and the surface or boundary of the surface on the object is recognized, further reducing the possibility of reduced recognition accuracy The effect that it can do is acquired.

On the other hand, according to the object recognition method of the invention 28, the same effect as the object recognition device of the invention 12 can be obtained.
Furthermore, according to the object recognition method of the invention 29, an effect equivalent to that of the object recognition device of the invention 13 can be obtained.
Furthermore, according to the object recognition method of the thirtieth aspect, the same effects as those of the object recognition apparatus of the eighteenth aspect can be obtained.

[First Embodiment]
A first embodiment of the present invention will be described below with reference to the drawings. FIGS. 1-12 is a figure which shows 1st Embodiment of the leg-wheel-type robot and leg-wheel apparatus which concern on this invention.
First, based on FIG. 1, the structure of the leg wheel apparatus which concerns on this invention is demonstrated.
Fig.1 (a)-(c) is a figure which shows the structure of the leg wheel apparatus 11 which concerns on this invention.

As shown in the front view of FIG. 1A, the leg wheel device 11 includes a shaft 15, a first pulley 16a, a second pulley 16b, a first belt 16c, a second gear box 16d, a first link 13, and a joint motor. The structure includes a leg drive mechanism 16 composed of 40 (described later).
As shown in the bottom view of FIG. 1B, the leg drive mechanism 16 is configured so that the rotation shaft of the joint motor 40 (hereinafter referred to as the first rotation shaft) is the rotation shaft of the first pulley 16a. The first pulley 16a is fitted into the shaft hole of the first pulley 16a, whereby the rotational driving force of the first rotating shaft of the joint motor 40 is transmitted to the first pulley 16a.

  Further, the first pulley 16a and the second pulley 16b are provided with grooves along the outer periphery, and in order to transmit the rotational driving force of the first pulley 16a to the second pulley 16b, both grooves are provided with the first pulley 16a and the second pulley 16b. One belt 16c is stretched over. That is, when the first belt 16c rotates due to the rotation of the first pulley 16a, the rotational driving force of the first belt 16c is transmitted to the second pulley 16b, and rotationally drives the second pulley 16b.

The second pulley 16b and the shaft 15 are configured such that the shaft 15 is fitted in the shaft hole of the second pulley 16b so that the rotational driving force of the second pulley 16b rotates the shaft 15. . Accordingly, the rotational driving force transmitted to the second pulley 16 b is transmitted to the shaft 15.
On the other hand, the second gear box 16d includes a plurality of gears and has a configuration in which the input shaft and the output shaft are a common shaft (for example, a planetary gear mechanism), and the shaft 15 is fitted into the shaft hole. It has a configuration. In the second gear box 16d, the rotational speed of the shaft 15 is reduced by a plurality of gears to obtain a necessary torque.

Moreover, as shown in the perspective views of FIGS. 1A and 1C, one end of the first link 13 is supported on the base 10 side via the shaft 15 and the support member 21, and the other end. The side rotates in conjunction with the rotation of the shaft 15.
Therefore, when the joint motor 40 rotationally drives the first rotating shaft, the rotational driving force is transmitted to the shaft 15 via the first pulley 16a, the first belt 16c, the second pulley 16b, and the second gear box 16d. When the shaft 15 is rotated by the transmitted rotational driving force, the other end side of the first link 13 is rotated in the rotation direction of the shaft 15.

As shown in FIG. 1A, the leg wheel device 11 further includes a bearing (not shown), a third pulley 17a, a fourth pulley 17b, a second belt 17c, a wheel 20, and a wheel motor 50 (described later). The wheel drive mechanism unit 17 is configured.
As shown in FIG. 1B, the wheel drive mechanism unit 17 is configured so that the rotation axis of the wheel motor 50 (hereinafter referred to as the second rotation axis) becomes the rotation axis of the third pulley 17a. It is configured to be fitted into the shaft hole of the pulley 17a, and thereby the rotational driving force of the second rotating shaft of the wheel motor 50 is transmitted to the third pulley 17a.

  The third pulley 17a and the fourth pulley 17b are provided with grooves along the outer periphery. In order to transmit the rotational driving force of the third pulley 17a to the fourth pulley 17b, both grooves are provided with the first pulley 17a and the fourth pulley 17b. Two belts 17c are stretched over. That is, when the third pulley 17a rotates, the second belt 17c rotates, and this rotational driving force is transmitted to the fourth pulley 17b, thereby rotating the fourth pulley 17b.

  Further, the fourth pulley 17b and the wheel 20 are configured such that both are integrated so that the rotational driving force of the fourth pulley 17b rotates the wheel 20. Accordingly, the rotational driving force transmitted to the fourth pulley 17b is transmitted to the wheel 20 as it is. A bearing (not shown) is provided inside the fourth pulley 17b and the wheel 20, and the wheel 20 and the fourth pulley 17b can rotate about the shaft 15 with the shaft 15 as an axis via the bearing. Is provided. That is, the leg drive mechanism 16 and the wheel drive mechanism 17 are integrally configured with the shaft 15 as a common axis. However, the bearing prevents the rotational driving force of the shaft 15 transmitted through the second gear box 16d from being transmitted to the wheels 20 and the fourth pulley 17b.

If it is the said structure, since the leg wheel apparatus 11 can arrange | position the wheel drive mechanism part 17 to the base | substrate 10 vicinity, it is possible to make the gravity center position of a leg wheel type robot low. Further, since the wheel 20 can be positioned in the vicinity of the base body 10, it is possible to reduce the inertia of the leg tip as compared with the configuration in which the wheel is provided on the conventional leg tip.
Next, a schematic configuration of the leg wheel type robot according to the present invention will be described with reference to FIG.

FIG. 2 is a front view of the leg wheel type robot 100 according to the present invention. FIG. 3 is a side view of the leg wheel type robot 100 according to the present invention.
As shown in FIGS. 2 and 3, the leg-wheel type robot 100 includes a base body 10 and four leg portions 12 connected to the base body 10.
The leg portion 12 connected to the base body 10 has a second configuration in which one end is connected to the other end side of the first link 13 of the leg wheel device 11 and the leg wheel device 11 via the third rotary joint 18. And a link 19.

The third rotary joint 18 includes a joint motor 40, a shaft, and a transmission mechanism that transmits the rotational driving force of the joint motor 40 to the shaft, and the second link in the rotational direction of the shaft by rotationally driving the shaft. The other end side of 19 is rotated.
The two leg portions 12 having such a configuration are coupled to the front side of the base body 10 at a symmetrical position via a support member 31. In addition, the two leg portions 12 are connected to the left and right symmetrical positions via the support member 31 also behind the base body 10.

  The first gear box 14 constitutes a first rotary joint (hereinafter referred to as the first rotary joint 14), and rotates with the direction orthogonal to the bottom surface of the leg wheel type robot 100 as the axial direction. That is, it rotates around the yaw axis. In addition, the leg wheel type robot 100 controls the wheel 20 by controlling the direction of rotation of the rotational driving force transmitted to the first gear box 14.

  The leg drive mechanism 16 (hereinafter also referred to as the second rotary joint 16) and the third rotary joint 18 are orthogonal to the side surface of the leg wheel type robot 100 when the first rotary joint 14 is in the state shown in FIG. Rotate in the axial direction. That is, when the first rotary joint 14 is in the state of FIG. 1, it rotates about the pitch axis, and when the first rotary joint 14 is rotated 90 degrees from the state of FIG. 1, it rotates about the roll axis. To do. Therefore, each leg 12 has three degrees of freedom.

That is, the first rotary joint 14 and the second rotary joint 16 constitute a hip joint part of the leg-wheel type robot 100, and the third rotary joint constitutes a knee joint part of the leg-wheel type robot 100.
At the tip of each leg 12, a front leg tip sensor 22 that measures the distance to an obstacle existing on the movement path of the leg wheel type robot 100, and a lower leg tip sensor 24 that measures the distance to the ground plane Is provided.

On the other hand, a horizontal laser 26 that irradiates a horizontal laser beam is provided in the upper center of the front surface of the substrate 10. In addition, vertical lasers 28 and 30 for irradiating vertical surface laser light are respectively provided on the center left and right of the front surface of the substrate 10.
A camera 32 that captures an image including reflected light of a horizontal plane laser beam and a vertical plane laser beam is provided at the lower center of the front surface of the substrate 10.

The horizontal laser 26 is provided so as to be inclined downward by a predetermined angle so that the camera 32 can capture an image including the reflected light of the horizontal laser beam. Similarly, the vertical laser 28 is tilted to the right by a predetermined angle so that the camera 32 can capture an image including reflected light of the vertical plane laser beam, and the vertical laser 30 is tilted to the left by a predetermined angle. ing.
Obstacle sensors 34 and 36 for detecting an obstacle are provided on the left and right of the camera 32, respectively.

  FIG. 4 is a diagram illustrating the configuration of the obstacle sensors 34 and 36. As shown in FIG. 4A, the obstacle sensors 34 and 36 can be configured by arranging a plurality of ultrasonic ranging sensors having low directivity in an array. Moreover, as shown in FIG.4 (b), it can also comprise by arrange | positioning a highly directional infrared ranging sensor in multiple array form. It is not limited to the configuration arranged in an array, and may be configured as a single unit. Moreover, you may comprise with the area sensor which arranged the ultrasonic ranging sensor or the infrared ranging sensor on the several plane. Thereby, the obstacle which exists on the movement path | route of the leg wheel type robot 100 can be roughly detected.

Next, the movement control system of the leg wheel type robot 100 will be described.
FIG. 5 is a block diagram showing a movement control system of the leg wheel type robot 100.
As shown in FIG. 5, joint motors 40 that rotationally drive the first to third rotary joints 14 to 18 are provided in the first to third rotary joints 14 to 18 of the respective leg portions 12. Each joint motor 40 is provided with an encoder 42 that detects the rotational angle position of the joint motor 40, and a driver 44 that controls the driving of the joint motor 40 based on the motor command signal and the output signal of the encoder 42.

  As described above, the third pulley 17a, the fourth pulley 17b, and the second belt 17c are capable of transmitting the rotational driving force (torque) of the wheel motor 50 to the rotating shaft of the wheel 20 of each leg portion 12. The wheel motors 50 are respectively connected via Each wheel motor 50 is provided with an encoder 52 that detects the rotational angle position of the wheel motor 50, and a driver 54 that controls the driving of the wheel motor 50 based on the motor command signal and the output signal of the encoder 52.

  The leg wheel type robot 100 further performs wireless communication with the CPU 60, the three-axis attitude sensor 70 that detects the attitude of the leg wheel type robot 100, the vision processor 72 that processes the image signal of the camera 32, and an external PC. The wireless communication unit 74 is configured to include a vision processor 72, a wireless communication unit 74, a hub 76 that relays input / output of the CPU 60, and a speaker 78 that outputs warning sound and the like.

The triaxial attitude sensor 70 includes a gyroscope or an acceleration sensor, or both, and detects the inclination of the attitude of the leg wheel type robot 100 with respect to the ground axis.
The CPU 60 outputs motor command signals to the drivers 44 and 54 via the motor command output I / F 61 and inputs output signals of the encoders 42 and 52 via the angle fetch I / F 62. In addition, sensor signals are input from the front leg tip sensor 22, the lower leg tip sensor 24, the obstacle sensor 34, and the triaxial posture sensor 70 via the sensor input I / F 63, respectively. Further, signals are input / output to / from the hub 76 via the communication I / F 64, and an audio signal is output to the speaker 78 via the sound output I / F 65.

Next, processing executed by the CPU 60 will be described.
The CPU 60 activates a control program stored in a predetermined area such as a ROM, and executes the conversion process to the wheel travel mode shown in the flowchart of FIG. 6 and the elevation control process shown in the flowchart of FIG. 8 according to the control program. .
FIG. 6 is a flowchart showing the conversion process to the wheel travel mode. FIG. 8 is a flowchart showing the elevation control process.

First, based on FIG. 6, the conversion process to wheel driving mode is demonstrated.
The conversion process to the wheel travel mode is a process for performing the travel control of the wheel 20 that is executed when the movement path of the leg-wheel type robot 100 is leveling. As shown in FIG.
In step S100, the output signal of each encoder 42 is input, and the process proceeds to step S102.

In step S102, the position of each leg 12 is calculated from the output signal of the encoder 42 input in step S100, and the process proceeds to step S104.
In step S104, based on the position calculated in step S102, it is determined whether or not each leg 12 is in the retracted position during wheel travel. If it is determined that the leg 12 is in the retracted position (Yes), the process proceeds to step S106. However, when it is determined that it is not in the retreat position (No), the process proceeds to step S112.

Here, FIG. 7A is a diagram showing an example when the leg portion 12 is in the retracted position, and FIG. 7B is a diagram showing an example when the leg portion 12 is not in the retracted position.
In the present embodiment, as shown in FIG. 7A, the retracted position is a position where each leg 12 is above the ground contact surface of the wheel 20 and is in a balance where the leg 12 does not naturally fall by its own weight. is there. Note that a support member that supports the leg portion 12 may be provided on the base body 10 so as not to fall naturally. If each leg 12 is in the retracted position shown in FIG. 7A, the process proceeds to step S106.

On the other hand, as shown in FIG.7 (b), when each leg part 12 exists below the contact surface of the wheel 20, it will transfer to step S112.
When the process proceeds to step S106, a motor stop signal for stopping the rotation of the joint motor 40 is output to the driver 44, and the process proceeds to step S108. Thereby, supply of the electric power which drives the leg part 12 to the joint motor 40 is stopped.

In step S108, a motor command signal to each driver 54 is generated, and the process proceeds to step S110.
In step S110, the motor command signal generated in step S108 is output to the driver 54, and the series of processes is terminated and the original process is restored.
On the other hand, if each leg 12 is not in the retracted position in step S104 and the process proceeds to step S112, the positional relationship between each leg 12 and the retracted position is calculated based on the output signal of each encoder 42 input in step S100. Then, the process proceeds to step S114.

In step S114, a motor command signal for each driver 44 is generated based on the positional relationship calculated in step S112, and the process proceeds to step S116.
In step S116, a motor command signal to each driver 44 is generated, and the process proceeds to step S100.
Next, the elevation control process will be described with reference to FIG.

The up / down control process is a process for performing the up / down control of the leg portion 12 that is executed when there is a step (obstacle) on the movement path of the leg-wheel type robot 100. As shown in FIG. 8, the process proceeds to step S200.
In step S200, an image is captured from the vision processor 72, and the process proceeds to step S202.

In step S202, step feature points are extracted by the light cutting method based on the captured image.
FIG. 9 is a diagram for explaining the principle of the light cutting method.
The light section method is a measurement method for obtaining coordinates on a measurement object based on the principle of triangulation. FIG. 7 shows the measurement coordinate system. The coordinates P (x0, y0, z0) on the measurement target are obtained by the following equation (1), where arbitrary coordinates on the image sensor of the camera 32 are Ps (xi, yi, zi).

  Next, from the obtained three-dimensional coordinates, a discontinuous point or a bent point of the reflected light of the laser beam is extracted as a feature point of the step. FIG. 10 is a diagram illustrating a state in which the step is irradiated with laser light and an image of the imaging element of the camera 32.

  When there is a convex step on the movement path of the leg wheel type robot 100, as shown on the left side of FIG. 10 (a), the horizontal plane laser light emitted from the horizontal laser 26 is reflected on the wall surface and floor surface of the step, An image of a step including the reflected light is taken by the camera 32. When image processing is performed on the image, a reflected light edge on the wall surface and a reflected light edge on the floor surface can be extracted as shown on the right side of FIG. Then, based on the edge image and the three-dimensional coordinates obtained by the above equation (1), the actual coordinates corresponding to the discontinuous points of the reflected light edge can be calculated.

  As shown on the left side of FIG. 10B, the vertical surface laser light emitted from the vertical laser 28 is reflected by the wall surface and the upper surface of the step, and the camera 32 captures an image of the step including the reflected light. . When image processing is performed on the image, a reflected light edge on the wall surface and a reflected light edge on the upper surface can be extracted as shown on the right side of FIG. The same applies to the vertical laser 30. As shown on the right side of FIG. 10C, the reflected light edge on the wall surface and the reflected light edge on the upper surface can be extracted. Based on these edge images and the three-dimensional coordinates obtained by the above equation (1), the actual coordinates for the bent point of the reflected light edge can be calculated.

Returning to FIG. 8, the process proceeds to step S <b> 204, the step width is calculated based on the extracted feature points, and the process proceeds to step S <b> 206.
In step S206, the actual coordinates of the upper surface of the step are calculated based on the extracted feature points, and the process proceeds to step S208.
In step S208, inverse kinematics calculation and centroid calculation are performed based on the calculated step width and actual coordinates of the upper surface and the sensor signal of the triaxial posture sensor 70, and the process proceeds to step S210.

In step S210, the landing position of the leg tip (the other end of the second link 19) is determined based on the calculation result of step S208, and the process proceeds to step S212.
In step S212, a motor stop signal for stopping the rotation of the wheel motor 50 is output to the driver 54, and the process proceeds to step S214. Thereby, supply of the electric power which drives the wheel 20 to the wheel motor 50 is stopped.

In step S214, sensor signals are input from the front leg tip sensor 22 and the lower leg tip sensor 24, respectively, and the process proceeds to step S216.
In step S216, the distance to the wall surface is calculated based on the sensor signal of the front leg tip sensor 22 input in step S214, and the process proceeds to step S218.
In step S218, the positional relationship between the leg tip and the upper surface is calculated based on the sensor signal of the lower leg tip sensor 24 input in step S214, and the process proceeds to step S220.

In step S220, a motor command signal to the driver 44 is generated based on the determined landing position and the calculated both distances, and the process proceeds to step S222.
In step S222, the motor command signal generated in step S220 is output to the driver 44, and the process proceeds to step S224.
In step S224, it is determined whether or not the leg tip has landed at the landing position. If it is determined that the leg tip has landed (Yes), the series of processes is terminated and the process returns to the original process. On the other hand, when it is determined in step S224 that the leg tip does not land (No), the process proceeds to step S112.

Next, the operation of the present embodiment will be described with reference to FIGS.
Here, FIGS. 11A to 11E are diagrams illustrating an example of the movement operation when the step over the leg wheel type robot 100 is overcome. FIG. 12 is a diagram illustrating an example of the movement operation when overcoming a high step.
When the leg-wheel type robot 100 determines that there is no obstacle on its movement path based on the sensor signals of the obstacle sensors 34 and 36, the leg-wheel type robot 100 starts the conversion process to the wheel traveling mode, and only the wheel 20 is detected. It shifts to the mode (henceforth wheel driving mode) which drives and moves.

  When the wheel travel mode is entered, an output signal of the encoder 42 corresponding to the joint motor 40 that drives each leg 12 is input via the angle capture I / F 62 (step S100), and each output signal is based on the input output signal. The position of the leg 12 is calculated (step S102). Specifically, since the rotation angle positions of the first to third joints 14 to 18 are obtained from the output signal of the encoder 42, the current position of each leg 12 is grasped from this rotation angle position.

When the position of each leg portion 12 is calculated, the position information of each leg portion 12 is compared with the position information of a predetermined retracted position. From the comparison result, whether each leg 12 is in the retracted position. It is determined whether or not (step S104).
If there is one of the four legs 12 that is not in the retracted position ("No" branch in step S104), the current rotational angle position of the leg 12 that is not in the retracted position, and The difference (positional relationship) between the retraction position and the rotation angle position corresponding to the leg 12 is calculated (step S112).

  When the positional relationship (difference) is calculated, a motor command signal is generated so as to rotate the rotation shaft of the joint motor 40 in the rotation direction in which the difference is set to “0” (step S114), and the generated motor command signal is Then, it outputs to the driver 44 corresponding to the relevant joint motor 40 (step S116). Thereby, the 1st link 13 and the 2nd link 19 which comprise the applicable leg part 12 rotate centering on each rotation joint toward a retracted position.

When each leg 12 has moved to the retracted position as described above ("Yes" branch in step S104), the driver 44 corresponding to each joint motor 40 that drives each leg 12 is then operated. Then, a motor stop signal for stopping the joint motor 40 is output (step S106). Thereby, the supply of drive power to each joint motor 40 of each leg 12 is cut off.
When each joint motor 40 is stopped, next, a motor command signal for the driver 54 of each wheel motor 50 for causing the leg wheel type robot 100 to travel in the moving direction is generated (step S108), and the generated motor command is generated. A signal is output to each driver 54 (step S110). Thereby, each wheel 20 rotates and moves the leg wheel type robot 100 in the moving direction.

On the other hand, when moving in the wheel travel mode, as shown in FIG. 11A, a convex step (obstacle) appears on the movement path of the leg wheel type robot 100, and the sensors of the obstacle sensors 34 and 36 are detected. When the presence of the step (obstacle) is detected based on the signal, the elevator control process is started, and the mode shifts to a mode in which only each leg 12 is driven and moved (hereinafter referred to as a leg moving mode). .
When shifting to the leg movement mode, first, the horizontal laser beam emitted from the horizontal laser 26 and the vertical plane laser beam emitted from the vertical lasers 28 and 30 are reflected by steps, and the reflected light is reflected by the camera 32. The containing image is taken. Next, an image photographed by the camera 32 is captured (step S200), and step feature points are extracted from the captured image (step S202). Then, the step width and the actual coordinates of the upper surface of the step are calculated based on the extracted feature points (steps S204 to S208), and the landing position of the leg tip is determined based on the calculated width of the step and the actual coordinates of the upper surface of the step. It is determined (step S210).

When the landing position is determined, a motor stop signal for stopping the wheel motor 50 is output to the driver 54 corresponding to the wheel motor 50 that drives each wheel 20 (step S212). Thereby, the supply of driving power to each wheel motor 50 is cut off.
Further, sensor signals are respectively input from the leg tip sensors 22 and 24 (step S214), and the distance to the wall surface and the positional relationship between the leg tip and the upper surface of the step are calculated (steps S216 to S218). Then, a motor command signal is generated based on the determined landing position and the calculated both distances (step S220), and the generated motor command signal is output to the driver 44 (step S222). As a result, the first to third rotary joints 14 to 18 are driven, and the first link 13 and the second link 19 are rotated. As shown in FIGS. 100 gets over the step while keeping the posture properly. Also, depending on the situation, the step is avoided and stopped. Therefore, the adaptability to a level difference is high like a legged robot.

  When overcoming the step, if there is no other step (obstacle) on the moving road, as shown in FIG. 11 (e), the vehicle shifts to the wheel travel mode again and travels only by the wheel 20. . That is, on leveling with no obstacles, the traveling movement is performed only by the wheels 20, and the steps (obstacles) are moved by walking using only the legs 12. And if it gets over a level | step difference, the traveling movement of only a wheel will be performed again.

  Further, the leg-wheel type robot 100 of the present embodiment has a convex high step on the moving path, as shown in FIG. 12, such that the rear leg extends completely when the leg portion 12 is used. In some cases, the joint motor 40 of each rotary joint is controlled so as to positively bring the wheel 20 into contact with the step. As a result, in addition to the low center of gravity, the number of contact points with the step increases, so that the step can be overcome while maintaining a stable posture. At this time, it is also possible to apply force in the direction over the step by driving and controlling the wheel motor 50 of the wheel 20 that is in contact with the step, which makes it possible to more reliably get over the step. Become. Further, by making the base 10 as small as possible, it is possible to further increase the sense of stability when overcoming the step.

Further, the leg-wheel type robot 100 according to the present embodiment controls the joint motor 40 of each rotary joint when traveling on the slope only with the wheels when the movement route is an inclined slope or the like, It is possible to change the posture of the leg 12 moved to the retracted position and change the position of the center of gravity of the leg-wheel type robot 100 so that it can run more stably.
As described above, the leg wheel type robot 100 includes the leg wheel device 11 constituting the leg portion 12 and the wheel 20 integrally with the second rotary joint 16 provided at the base side end portion of the first link 13. The wheel motor 50 is disposed in the vicinity of the wheel 20 via the third pulley 17a, the second belt 17c, and the third pulley 17b.

Thereby, since the wheel 20 and the wheel motor 50 are disposed in the vicinity of the base body 10, it is possible to lower the position of the center of gravity of the leg wheel type robot. In addition, the inertia of the leg tip can be reduced as compared with the conventional configuration in which the wheel is provided on the leg tip.
Further, when the movement is performed using only the wheel 20, the leg portion 12 positioned below the ground contact surface of the wheel 20 can be moved to a retracted position above the ground contact surface.

Thereby, it is possible to reliably prevent the leg portion 20 from obstructing traveling when traveling with only the wheel 20.
Further, when moving using only the wheels 20, it is possible to cut off the supply of drive power (servo-off) to each joint motor 40 that drives the leg 12.
Thereby, energy consumption in each joint motor 40 can be reduced.

Further, when the movement is performed using only the leg portion 12, it is possible to cut off the supply of drive power (servo-off) to each wheel motor 50 that drives the wheel 20.
Thereby, energy consumption in each wheel motor 50 can be reduced.
Further, when the leg portion 12 is used to get over the step, each indirect motor 40 can be driven and controlled so as to get over the wheel 20 while contacting the step.

As a result, even a relatively high level difference that cannot be overcome by a robot with wheels provided on the conventional leg tips can be overcome by increasing the number of contacts by contact with the wheels 20.
In addition, when the vehicle travels on a moving path that is not flat, such as a hill, the posture of the leg 12 moved to the retracted position can be changed to change the position of the center of gravity of the leg-wheel type robot 100.

Thereby, it is possible to make the leg wheel type robot 100 perform more stable wheel running on a slope.
Further, in the present embodiment, an image sensor including the lasers 26 to 30 and the camera 32 and the leg tip sensors 22 and 24 are provided. Based on the image captured by the camera 32 and the distance measured by the leg tip sensors 22 and 24. Then, a step such as a staircase is recognized, and the joint motor 40 is controlled based on the recognition result.

Thereby, since the raising / lowering control of the leg part 12 is performed while recognizing the unknown step using the image sensor and the leg tip sensors 22 and 24, high adaptability to the unknown step can be realized. In addition, since it can operate in an environment where people are active, it is suitable for home robots, personal robots, and the like that are used for acting with people.
Further, in the present embodiment, the image sensor is provided on the front surface of the base body 10, and the leg tip sensors 22 and 24 are provided on the distal ends of the leg portions 12.

This makes it possible to detect an obstacle present on the movement path of the leg wheel type robot 100 with a wide field of view and to accurately measure the distance between the wheel 20 and the stairs when the stairs are raised and lowered.
Furthermore, in this embodiment, the lasers 26 to 30 that irradiate the laser beam at a predetermined angle with respect to the moving direction, and an image that is provided at a predetermined distance from the lasers 26 to 30 and that includes the reflected light of the laser beam are captured. A camera 32 is provided, and a step such as a staircase is recognized by a light cutting method based on an image photographed by the camera 32.

Thereby, since the characteristic effective for the raising / lowering control of the leg part 12 can be detected among the characteristics of the step, it is possible to realize higher adaptability to the unknown step.
Furthermore, in the present embodiment, the width of the step is calculated based on the imaging state of the reflected light of the horizontal plane laser light emitted from the horizontal laser 26, and the two vertical surface laser lights emitted from the vertical lasers 28 and 30 are calculated. Based on the imaging state of the reflected light, the actual coordinates of the upper surface of the cut step are calculated.

As a result, it is possible to detect a feature that is more effective for raising and lowering the leg portion 12 among the features of the step, and thus it is possible to realize higher adaptability to an unknown staircase.
Further, in the present embodiment, the distance to the wall surface of the step is calculated based on the measurement result of the front leg tip sensor 22, and the positional relationship between the wheel 20 and the upper surface of the step is determined based on the measurement result of the lower leg tip sensor 24. calculate.

As a result, it is possible to detect a feature that is more effective for raising / lowering control of the leg portion 12 among the features of the step, thereby realizing higher adaptability to an unknown step (for example, various steps). be able to.
In the said embodiment, the leg wheel apparatus 11 respond | corresponds to the leg wheel apparatus of invention 8 and 9, the wheel 20 respond | corresponds to the wheel of invention 1-5 and 7-9, and the leg part 12 is invention 1. Corresponds to 9 legs.

  Moreover, in the said embodiment, the joint motor 40 respond | corresponds to the actuator of invention 1, 8 and 9, and the 1st actuator of invention 2-5 and 7, and the wheel motor 50 is an actuator of invention 1, 8 and 9. Corresponding to the second actuators of the inventions 2 and 6, steps S100 to S116 and steps S200 to S224 correspond to the control means of the inventions 1 and 3 to 7, controlling the joint motor 40 of each rotary joint, The process of changing the posture of the leg 12 moved to the retracted position and changing the position of the center of gravity of the leg wheel type robot 100 corresponds to the leg posture changing means of the eleventh aspect.

In the above embodiment, the leg-wheel type robot according to the present invention is applied to the case of overcoming the convex step. However, the present invention is not limited to this, and the same applies to the case of overcoming the step other than the convex step. Can be applied.
Moreover, in the said embodiment, in the movement control using only the wheel 20, after moving each leg part 12 to a retracted position, control which cuts off the electric power supplied to the joint motor 40 of each said leg part 12 and However, the present invention is not limited to this, and in the case of a configuration in which each leg 12 falls due to its own weight, a configuration may be adopted in which the minimum drive power necessary to prevent the fall is supplied to each joint motor 40.

  Moreover, in the said embodiment, although the leg-wheel type robot which concerns on this invention was set as the structure which has a total of four leg parts of two front leg parts and two rear leg parts, it is not restricted to this, It is good also as a structure which has 2 (pair) or 6 (3 pairs) or more. However, it is preferable that the leg portion can be moved to a position higher than the ground contact portion of the wheel (or a position that does not hinder wheel traveling) during traveling movement using only the wheels.

Moreover, in the said embodiment, although it was set as the structure which provides the wheel motor 50 with respect to each wheel 20 (4 wheel drive), it is not restricted to this, either of two rear leg parts or two front leg parts It is good also as a structure provided in one side. As a result, the weight of two motors can be reduced.
Moreover, in the said embodiment, it was set as the structure which drive-controls all the wheel motors 50 of the four leg parts 12 at the time of the movement using only the wheel 20, but it is not restricted to this, Environment Accordingly, the vehicle may be driven by driving only the wheel motor 50 that drives either the front two wheels or the rear two wheels.

  In the above embodiment, the rotational driving force of the first rotating shaft of the joint motor 40 is converted to the shaft 15 and the second gear box 16d via the first and second pulleys 16a and 16b and the first belt 16c. However, the present invention is not limited to this, and the configuration may be such that the rotational driving force of the first rotating shaft is transmitted to the shaft 15 and the second gear box 16d via a plurality of gears.

Moreover, in the said embodiment, it was set as the structure which transmits the rotational driving force of the 2nd rotating shaft of the wheel motor 50 to the wheel 20 via the 3rd and 4th pulleys 17a and 17b and the 2nd belt 17c. However, the configuration is not limited to this, and the rotational driving force of the second rotating shaft may be transmitted to the wheels 20 via a plurality of gears.
[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to the drawings. 13 to 31 are diagrams showing a second embodiment of the leg-wheel type robot, the object recognition apparatus, and the object recognition method according to the present invention.

First, the configuration of a leg wheel type robot 100 to which the present invention is applied will be described.
FIG. 13 is a front view of the leg wheel type robot 100.
FIG. 14 is a side view of the leg wheel type robot 100.
As shown in FIGS. 13 and 14, the leg-wheel type robot 100 includes a base body 10 and four leg portions 12 connected to the base body 10.

Two legs 12 are connected to the front portion of the base body 10 via a rotary joint 14 at symmetrical positions. In addition, two legs 12 are connected to the rear part of the base body 10 via a rotary joint 14 at symmetrical positions. The rotary joint 14 rotates with the direction orthogonal to the bottom surface of the leg wheel type robot 100 as an axial direction. That is, it rotates around the yaw axis.
Each leg portion 12 is provided with two rotary joints 16 and 18. The rotary joint 14 rotates with the lower side as the axial direction, and the rotary joints 16 and 18 rotate with the direction orthogonal to the side surface of the leg wheel type robot 100 as the axial direction when the rotary joint 14 is in the state of FIG. . That is, when the rotary joint 14 is in the state of FIG. 13, it rotates about the pitch axis, and when the rotary joint 14 is rotated 90 degrees from the state of FIG. 13, it rotates about the roll axis. Therefore, each leg 12 has three degrees of freedom.

A driving wheel 20 is rotatably provided at the tip of each leg 12 with the same axial direction as the rotary joints 16 and 18.
At the tip of each leg 12, a front leg tip sensor 22 for measuring the distance to an object existing on the movement path of the leg wheel type robot 100 and a lower leg tip sensor 24 for measuring the distance to the ground plane are provided. Is provided.

  On the other hand, a three-dimensional distance measuring device 200 is attached to the front surface of the base body 10. The coordinate system (hereinafter referred to as a sensor coordinate system) of the three-dimensional distance measuring apparatus 200 has a depth (front-rear length) direction of the base body 10 as an xrs axis, and a width (left-right length) direction of the base body 10 as a yrs axis. The height direction of the substrate 10 is the zrs axis, the xrs axis is the front of the substrate 10, the yrs axis is the right side of the substrate 10, and the zrs axis is the positive direction above the substrate 10.

Next, the external structure of the three-dimensional distance measuring device 200 will be described.
FIG. 15 is a front view (yrs-zrs plane) of the three-dimensional distance measuring apparatus 200.
FIG. 16 is a side view (xrs-zrs plane) of the three-dimensional distance measuring apparatus 200.
FIG. 17 is a top view (yrs-xrs plane) of the three-dimensional distance measuring apparatus 200.
As shown in FIGS. 15 to 17, the three-dimensional distance measuring apparatus 200 is provided with a lower support plate 204, an upper support plate 206 provided above the lower support plate 204, and an upper support plate 206. The camera support plate 208 is configured. The lower support plate 204 and the upper support plate 206, and the upper support plate 206 and the camera support plate 208 are supported by a plurality of columns, respectively.

As shown in FIG. 16, the camera support plate 208 is provided so as to protrude in the positive direction of the xrs axis with respect to the lower support plate 204 and the upper support plate 206. A camera 222 is attached to the protruding portion of the camera support plate 208.
A motor 216 is attached to the lower surface of the lower support plate 204. A rotation shaft of the motor 216 (hereinafter referred to as a drive rotation shaft) penetrates the lower support plate 204 from below and is connected to a pulley 220 a disposed between the lower support plate 204 and the upper support plate 206. .

  On the other hand, a two-dimensional distance measuring device 212 is attached to a lower surface of the lower support plate 204 at a position spaced apart from the motor 216 in the horizontal direction by a predetermined distance. The two-dimensional distance measuring device 212 has a rotation shaft (hereinafter referred to as a driven rotation shaft), and the driven rotation shaft passes through the lower support plate 204 from below, and is between the lower support plate 204 and the upper support plate 206. The pulley 220b is connected to the pulley 220b.

A belt 221 is wound around the pulleys 220a and 220b. Accordingly, when the pulley 220a is rotated by the motor 216 and the pulley 220b is rotated by the belt 221 wound around the pulley 220a, the two-dimensional distance measuring device 212 rotates around the zrs axis as shown in FIG.
FIG. 18 is a diagram illustrating a scanning range of the distance measuring sensor.

  The two-dimensional distance measuring device 212 has a built-in distance measuring sensor. As shown in FIG. 18, the two-dimensional distance measuring device 212 rotates at a predetermined scanning unit angle while rotating the distance measuring sensor about the zrs axis and an axis orthogonal to the measurement direction. The measurement result of the distance measuring sensor is acquired. The scanning range of the distance measuring sensor is set so that the leg wheel type robot 100 scans mainly below the leg wheel type robot 100 because the leg wheel type robot 100 is intended to move up and down stairs and avoid obstacles. . At the origin position of the two-dimensional distance measuring device 212 and the distance measuring sensor (the positions where the scanning angles θ and φ are 0 °), the measuring direction of the distance measuring sensor coincides with the xrs axis, and the rotation axis of the distance measuring sensor is It matches the yrs axis. Although the direction of the rotation axis of the distance measurement sensor changes depending on the scanning angle of the two-dimensional distance measurement device 212, it coincides with the yrs axis at the origin position. Therefore, for convenience of explanation, the rotation axis of the distance measurement sensor is expressed as the yrs' axis. To do.

  In the three-dimensional distance measuring device 200, the rotation driving mechanism (motor 216, encoder 218, pulleys 220a and 220b, belt 221 and lower support plate 204) that rotates and drives the two-dimensional distance measuring device 212 has a scanning range shown in FIG. Since it is provided outside, within the scanning range shown in FIG. 18, the scanning of the distance measuring sensor 212 a is not hindered by each mechanism unit constituting the three-dimensional distance measuring apparatus 200.

  Further, since it is only necessary to be able to recognize an obstacle on the travel route of the leg-wheel type robot 100, the scanning range by the rotational drive around the zrs axis does not need to cover up to 180 ° forward, and the horizontal range from the two-dimensional distance measuring device 212 is not necessary. A range in which the motor 216 and the encoder 218 arranged at a predetermined distance in the direction are out of the scanning range is also sufficient. Therefore, the rotational driving range of the two-dimensional distance measuring device 212 is set to a range not including the motor 216 and the encoder 218.

Next, the movement control system of the leg wheel type robot 100 will be described.
FIG. 19 is a block diagram showing a movement control system of the leg wheel type robot 100.
As shown in FIG. 19, joint motors 40 that rotationally drive the rotary joints 14 to 18 are provided in the rotary joints 14 to 18 of the respective leg portions 12. Each joint motor 40 is provided with an encoder 42 that detects the rotational angle position of the joint motor 40, and a driver 44 that controls the driving of the joint motor 40 based on the motor command signal and the output signal of the encoder 42.

A wheel motor 50 that rotationally drives the drive wheel 20 is provided on the drive wheel 20 of each leg 12. Each wheel motor 50 is provided with an encoder 52 that detects the rotational angle position of the wheel motor 50, and a driver 54 that controls the driving of the wheel motor 50 based on the motor command signal and the output signal of the encoder 52.
The leg-wheel type robot 100 further includes a CPU 60, a three-axis attitude sensor 70 that detects the attitude of the leg-wheel type robot 100, a wireless communication unit 74 that performs wireless communication with an external PC, the wireless communication unit 74, and the CPU 60. Are provided with a hub 76 that relays the input / output of the sound and a speaker 78 that outputs a warning sound or the like.

The triaxial attitude sensor 70 includes a gyroscope or an acceleration sensor, or both, and detects the inclination of the attitude of the leg wheel type robot 100 with respect to the ground axis.
The CPU 60 outputs motor command signals to the drivers 44 and 54 via the motor command output I / F 61 and inputs output signals of the encoders 42 and 52 via the angle fetch I / F 62. In addition, sensor signals are input from the three-dimensional distance measuring device 200, the front leg tip sensor 22, the lower leg tip sensor 24, and the three-axis posture sensor 70 via the sensor input I / F 63, respectively. Further, signals are input / output to / from the hub 76 via the communication I / F 64, and an audio signal is output to the speaker 78 via the sound output I / F 65.

Next, the control structure of the two-dimensional distance measuring device 212 will be described.
FIG. 20 is a block diagram showing a control structure of the two-dimensional distance measuring device 212.
As shown in FIG. 20, the two-dimensional distance measuring device 212 includes a distance measuring sensor 212a that measures a distance to a measurement point on an object that exists within the measurement range, a motor 212c that rotates the distance measuring sensor 212a, The encoder 212d is configured to detect the rotational angle position of the motor 212c, and the driver 212b is configured to control the driving of the motor 212c based on the command signal and the output signal of the encoder 212d.

The driver 212b has a scanning angle range (for example, a predetermined angle range such as −40 ° to + 40 °) and a scanning unit angle (for example, a predetermined unit such as 0.36 °) set in the command signal from the sensing processor 210. Based on the angle, control is performed to rotate the rotation axis of the motor 212c by a scanning unit angle.
The motor 212c is provided so as to rotate and drive a laser output unit (not shown) and a light receiving unit (not shown) of the distance measuring sensor 212a around the yrs' axis. Are rotated by a scanning unit angle (Δθ).

Next, the control structure of the three-dimensional distance measuring apparatus 200 will be described.
FIG. 21 is a block diagram showing a control structure of the three-dimensional distance measuring apparatus 200.
As shown in FIG. 21, the three-dimensional distance measuring apparatus 200 includes a sensing processor 210, a two-dimensional distance measuring apparatus 212, a motor 216, an encoder 218, a command signal, and an output signal of the encoder 218. A driver 214 that controls driving and a camera 222 are included.

  The sensing processor 210 executes a dedicated program, gives a command signal to the driver 212b, rotates the distance measuring sensor 212a, and is within an area that can be measured within the scanning range of the distance measuring sensor 212a (hereinafter referred to as a scanning plane). A two-dimensional distance measuring device that executes a first scanning process for measuring a distance to a measurement point on an existing object and gives a command signal to the driver 214 each time the first scanning process for one scanning plane is completed. A second scanning process for rotating 212 is executed.

The sensing processor 210 further operates on the object existing in the measurement range based on the distance information (hereinafter referred to as distance information) measured by the two-dimensional distance measurement device 212 through the first scanning process and the second scanning process. The process of recognizing the continuous surface is executed.
Next, the principle of distance measurement of the three-dimensional distance measuring apparatus 200 will be described.
FIG. 22 is a diagram for explaining the principle of distance measurement of the two-dimensional distance measuring device 212.

  The two-dimensional distance measuring device 212 is as shown in FIG. 22 every time the distance measuring sensor 212a rotates by the scanning unit angle around the yrs' axis according to the rotational drive of the rotating shaft of the motor 212c. In addition, laser light is output from the laser output unit, and reflected light from an object (obstacle in FIG. 22) with respect to the output light is received by the light receiving unit, and a distance corresponding to each scanning angle (measurement distance in FIG. 22) L (distance between the object and the light receiving unit)) is measured.

FIG. 23 is a diagram illustrating a case where scanning is performed by the first scanning process and the second scanning process. FIG. 6A is a diagram showing the relationship between the measurement distance L and the scanning angle θ when the distance measurement sensor 212a is rotated about the yrs ′ axis, and FIG. 6B is a two-dimensional distance measurement device. It is a figure which shows the relationship between the scanning plane when 212 is rotated around the zrs axis, and the scanning angle φ.
In the first scanning process, for example, as shown in FIG. 23A, the distance measuring sensor 212a is rotated by the scanning unit angle around the yrs' axis while each scanning angle with respect to the origin position (in FIG. 23A). This is a process of measuring distance information (L (θ ₁ ), L (θ ₂ ), L (θ ₃ ) in FIG. 23A) according to θ ₁ , θ ₂ , θ ₃ ).

In the first scanning process, a plane formed by connecting the rotation center of the rotating shaft of the motor 212c and both ends of the scanning trajectory line of the laser is a scanning plane (a fan-shaped plane when no object is present). .
The driver 214 performs control to rotate the rotation axis of the motor 216 by the scanning unit angle based on the scanning angle range and the scanning unit angle (Δφ) set in the command signal from the sensing processor 210.

  The motor 216 is provided to rotationally drive the two-dimensional distance measuring device 212 around the zrs axis via a speed reducer (not shown), pulleys 220a and 220b, and a belt 221, and receives a control signal from the driver 214. Correspondingly, the rotation axis of the self is rotated by the scanning unit angle. As a result, the rotational driving force is transmitted to the driven rotational shaft via the pulleys 220a and 220b in accordance with the rotational driving of the rotational shaft of the motor 216, and the two-dimensional distance measuring device 212 rotates about the zrs axis by a scanning unit angle. .

That is, the second scanning process is a process of rotating the two-dimensional distance measuring device 212 by the scanning unit angle around the zrs axis as shown in FIG. Then, by performing the first scanning process and the second scanning process alternately and continuously, the scanning plane formed by the first scanning process is continuously formed around the zrs axis.
FIG. 24 is a diagram illustrating a distance measurement example of the three-dimensional distance measurement apparatus 200.

Thereby, for example, as shown in FIG. 24, the three-dimensional shape of an object such as a wall, a wall, a stand, or a shelf can be grasped.
Further, as shown in FIG. 23 (b), the distance information of each measurement point after the second scanning process is expressed as L (θ _i , φ _j ). Here, i is a serial number given to each measurement point according to the scanning angle around the yrs' axis, and j is a serial number given to each measurement point according to the scanning angle around the zrs axis.

Next, an object recognition process executed by the three-dimensional distance measuring apparatus 200 will be described.
FIG. 25 is a flowchart showing object recognition processing executed by the three-dimensional distance measuring apparatus 200.
The object recognition process is a process realized by the sensing processor 210 reading a dedicated program stored in a ROM (not shown) based on a command signal from the CPU 60 and executing the read program. When the process is executed, the process first proceeds to step S300 as shown in FIG.

In step S300, in the three-dimensional distance measuring apparatus 200, the scanning angle range and the scanning unit angle of the distance measuring sensor 212a and the two-dimensional distance measuring apparatus 212 are set based on the command signal from the CPU 60, and the process proceeds to step S302. Here, the command signal from the CPU 60 includes information on the scanning angle range and the scanning unit angle.
In step S302, by outputting a command signal to the two-dimensional distance measuring device 212, the driver 212b, the motor 212c, and the encoder 212d are driven, and the distance measuring sensor 212a is scanned around the yrs' axis set in step S300. Within the range, the scanning unit angle set in step S300 is rotated about the yrs' axis, and the first scanning process for measuring the distance information corresponding to each scanning angle is executed, and the process proceeds to step S304.

In step S304, a filtering process using a median filter is performed on the distance information measured in step S302 to remove noise components, and the process proceeds to step S306.
In step S306, the distance information of the rotating coordinate system after noise removal in step S304 is converted into the coordinate information of the orthogonal coordinate system. Thereby, the distance information of each measurement point obtained by the first scanning process is converted into coordinate information of an orthogonal coordinate system (hereinafter referred to as a scanning plane coordinate system) in which the scanning plane of the first scanning process is a two-dimensional plane. Converted.

Next, the process proceeds to step S310, and a line segment in the orthogonal coordinate system is detected by Hough transform based on the coordinate information transformed in step S306.
FIG. 26 is a diagram for explaining the principle of the Hough transform. FIG. 4A shows the xy plane, and FIG. 4B shows the ρ-θ plane. Note that the x-axis and y-axis in FIG. 5A indicate axes in the scanning plane coordinate system and are separate from the axes in the sensor coordinate system.

  The Hough transform is one of feature extraction methods used in digital image processing. Classically, it used to detect straight lines, but it is more generalized and used for various forms (those that can be expressed in the form of equations such as circles and ellipses). A feature of the Hough transform is that a relatively good result can be obtained even when a straight line in the image is cut off in the middle or when noise exists.

Consider a straight line ax + by + c = 0 in the scanning plane coordinate system, as shown in FIG.
When a perpendicular is drawn from this straight line to the origin, the length of the perpendicular is ρ, and the angle between the perpendicular and the x axis is θ, this straight line can be expressed by the following equation (2).

The above equation (2) can be transformed into the following equation (3).

ρ = xcosθ + ysinθ (3)

Therefore, one straight line corresponds to one set of (ρ, θ). Here, the point (ρ, θ) is referred to as the Hough transform of the straight line ax + by + c = 0. A straight line group passing through an arbitrary point (x0, y0) in the scanning plane coordinate system can be expressed by the following equation (4).

ρ = x0cosθ + y0sinθ (4)

Here, when the locus of each straight line group passing through the three points P1, P2, and P3 on the xy plane is drawn on the ρ-θ plane, a sinusoidal curve is obtained as shown in FIG. If these three points exist on the same line in the xy plane, the values of ρ and θ are the same, and the curves corresponding to the three points intersect at one point on the ρ-θ plane.

If the principle of the Hough transform is used, a line segment can be detected based on the coordinates of a plurality of measurement points. That is, for n (n ≧ 2) measurement points, n curves are drawn on the ρ-θ plane, and m (n ≧ m ≧ 2) curves among them intersect at one point. For example, the m measurement points corresponding to the m curves are on the same straight line in the xy plane.
Next, as shown in FIG. 25, the process proceeds to step S320, and the end point of the detected line segment is determined as the boundary (continuous edge) of the continuous surface. When multiple line segments overlap or when multiple line segments exist within a predetermined distance, it is considered as one line segment, and the two farthest points among the end points of these line segments are Judge as a boundary.

Next, the process proceeds to step S324, where the coordinate information of the end point determined as the boundary of the continuous surface is converted into a sensor coordinate system, and the converted coordinate information is associated with each line segment in a memory (not shown) such as a RAM. Store, and the process proceeds to step S326.
In step S326, it is determined whether or not the processing in steps S302 to S324 has been completed for all scanning planes corresponding to the scanning angle range and scanning unit angle of the second scanning processing, and when it is determined that the processing has been completed (Yes) ) Proceeds to step S336.

  In step S336, surface data is generated based on the coordinate information stored in the memory. Since the line segment connecting the end points determined as the boundary of the continuous plane (which is regarded as one line segment in step S320) is an intersection line where the continuous plane and the scanning plane intersect, generation of plane data is, for example, The slope and coordinates of the line segment connecting the end points determined as the boundary of the continuous surface in a certain scanning plane and the line segment connecting the end points determined as the boundary of the continuous surface in the scanning plane adjacent to the zrs axis are within a predetermined range. Are determined as continuous surfaces, coordinate information corresponding to these line segments is associated, or connected by using a known interpolation method. For example, since a continuous surface having an inclination close to 0 can be regarded as a horizontal surface, it can be determined that the surface is a walking surface.

Next, the process proceeds to step S338, and the surface data generated in step S336 is output to the CPU 60 via the hub 76 and the communication I / F 64, and the series of processing ends.
On the other hand, when it is determined in step S326 that the processes in steps S302 to S324 are not completed for all scanning planes (No), the process proceeds to step S340, and a command signal is output to the three-dimensional distance measuring apparatus 200. The driver 214, the motor 216, and the encoder 218 are driven, and the two-dimensional distance measuring device 212 is rotated around the zrs axis by the scanning unit angle set in step S300 within the scanning angle range around the zrs axis set in step S300. The second scanning process is performed to rotate to step S302, and the process proceeds to step S302.

Next, processing executed by the CPU 60 will be described.
The CPU 60 activates a control program stored in a predetermined area such as a ROM, and executes the elevation control process shown in the flowchart of FIG. 27 according to the control program.
FIG. 27 is a flowchart showing the elevation control process.
The elevation control process is a process for performing the elevation control of the leg portion 12. When the elevation control process is executed by the CPU 60, the process first proceeds to step S400 as shown in FIG.

In step S400, surface data is input from the three-dimensional distance measuring apparatus 200, the process proceeds to step S402, and the coordinates of each measurement point in the sensor coordinate system are converted into coordinates in the global coordinate system based on the input surface data. A point on the periphery of the continuous surface is detected as a feature point of the staircase.
Next, the process proceeds to step S404, the width of the staircase is calculated based on the detected feature point of the staircase, and the process proceeds to step S406, where the actual coordinates of the stair nosing part of the staircase are calculated based on the detected feature point of the staircase. Then, the process proceeds to step S408.

In step S408, inverse kinematics calculation and centroid calculation are performed based on the calculated width of the staircase and the actual coordinates of the stair nose and the sensor signal of the three-axis posture sensor 70, the process proceeds to step S410, and the calculation result of step S408 The landing position of the leg tip (drive wheel 20) is determined based on the above, and the process proceeds to step S412.
In step S412, sensor signals are input from the front leg tip sensor 22 and the lower leg tip sensor 24, respectively, and the process proceeds to step S414 to calculate the distance to the kick plate based on the input sensor signal of the front leg tip sensor 22. Then, the process proceeds to step S416, the positional relationship between the leg tip and the tread is calculated based on the input sensor signal of the lower leg tip sensor 24, and the process proceeds to step S418.

In step S418, a motor command signal to the drivers 44 and 54 is generated based on the determined landing position and the calculated both distances, the process proceeds to step S420, and the generated motor command signal is output to the drivers 44 and 54. The process proceeds to step S422.
In step S422, it is determined whether or not the leg tip has landed on the tread. When it is determined that the leg tip has landed (Yes), the series of processes is terminated and the original process is restored.

On the other hand, when it is determined in step S422 that the leg tip does not land (No), the process proceeds to step S412.
Next, the operation of the present embodiment will be described.
A case will be described in which a stairway exists on the movement path of the leg-wheel type robot 100 and the stairs are overcome.

In the sensing processor 210, first, through step S300, the scanning angle range and the scanning unit angle are set in the sensing processor 210 based on the command signal from the CPU 60.
Here, it is assumed that the two-dimensional distance measuring device 212 is a two-dimensional range sensor having a distance measurement range of 20 to 4095 [mm], a maximum scanning angle range of 240 °, and an angular resolution of 0.36 °. If the scanning angle range is 240 °, it is the same as the scanning angle range forming the scanning plane shown in FIG. 18, and the lower support plate 204, the pulleys 220a and 220b, and the belt 221 above the two-dimensional distance measuring device 212 It will not be included in the scanning range.

  Further, a scanning angle range of 240 ° and a scanning unit angle of 0.36 ° are set for the first scanning process, and a scanning angle range of −40 ° to + 40 ° and a scanning unit angle of 10 ° are set for the second scanning process. Is set (in this case, nine scanning planes are formed). If the scanning angle range is −40 ° to + 40 °, the motor 216 and the encoder 218 arranged at a predetermined distance in the horizontal direction from the two-dimensional distance measuring device 212 are not included in the scanning range.

Next, through step S302, a command signal is output to the driver 212b based on the scan angle range and scan unit angle set for the first scan process, whereby the first scan process is executed. Initially, a first scanning process is performed on a position (origin position) where the scanning angle φ around the zrs axis is 0 °.
As a result, based on the command signal from the sensing processor 210 and the output signal from the encoder 212d, the driver 212b drives the rotation shaft of the motor 212c to rotate, and the distance measuring sensor 212a scan unit angle Δθ = about the yrs ′ axis. While rotating by 0.36 °, the distance corresponding to each scanning angle is measured. Each distance information is output to the sensing processor 210 as a data string L (θ _i , φ _j ).

In the scanning range around the yrs' axis, there is no object other than the base 10 that obstructs scanning, such as the driving mechanism of the two-dimensional distance measuring device 212. Distance information can be obtained.
When the first scanning process for one scanning plane is completed, the filtering process is performed on the distance information measured in the first scanning process through step S304. Thereby, the noise component in measurement information is removed.

FIG. 28 is a graph showing a measurement result by the first scanning process.
Here, the measurement distance L [mm] of each measurement point after removing the noise component is as shown in FIG. 28, for example. In FIG. 28, the horizontal axis represents the number of the measurement point corresponding to each scanning angle (first scanning angle number), and the vertical axis represents the measurement distance L [mm] to the measurement point of each scanning angle number.
In the example of FIG. 28, it can be seen that there are stairs on the walking path of the leg-wheel type robot 100 with a constant step and a continuous tread board.

Next, through step S306, the distance information of the rotated coordinate system after the filtering process is converted into the coordinate information of the orthogonal coordinate system.
FIG. 29 is a graph showing the result of converting the distance information of the rotating coordinate system of each measurement point of FIG. 28 into the coordinate information of the orthogonal coordinate system.
The distance information of the rotating coordinate system of each measurement point in FIG. 28 is obtained by coordinate conversion, as shown in FIG. 29, the distance [mm] in the xrs axis direction and the distance [mm] in the zrs axis direction corresponding to each scanning angle. Is two-dimensional coordinate information. In FIG. 29, the horizontal axis represents the distance L _x [mm] in the xrs axis direction, and the vertical axis represents the distance L _z [mm] in the zrs axis direction.

Next, through step S310, a line segment in the orthogonal coordinate system is detected by Hough transform based on the transformed coordinate information.
FIG. 30 is a graph showing measurement points in the orthogonal coordinate system and the results of the Hough transform.
In the orthogonal coordinate system, each measurement point is represented as a set of a plurality of points along the contours of the kick board and the tread board as shown in FIG. In the example of FIG. 30 (a), in the region corresponding to the first step tread, some measurement points are distributed in a region deviating from the continuous surface. The measurement results vary due to the influence of the error area A1. The area A2 has a lower measurement resolution than the other areas.

When the Hough transform is performed on the measurement result, as shown in FIG. 30B, a line segment along the contour of each tread is detected.
As another method for detecting a line segment based on a plurality of measurement points, a least square method is known.
However, in the least square method, line segments are detected by tracing each measurement point, and therefore, in the low resolution area A2, a line segment that does not follow the contour of the tread may be detected. On the other hand, in the Hough transform, it is difficult to be affected by the measurement resolution, and even if the low resolution region A2 is included, as shown in FIG. Can do.

  Further, in the least square method, line segments are detected by tracing each measurement point, so that the error region A1 is detected as an oblique line segment that is actually a flat line segment. On the other hand, in the Hough transform, if it is not easily affected by variations and the number of variations is small, the error region A1 and the regions on both sides thereof can be detected as flat line segments as shown in FIG. it can.

  Further, the least square method has a problem as to whether to recognize a region from where to where is one continuous surface. In this case, for example, it is conceivable to recognize a point where the slope of the detected line segment changes abruptly as the boundary of the continuous surface. However, in this recognition method, the error region A1 is actually the error region A1 and the regions on both sides thereof. Is a single continuous surface, the regions on both sides are recognized as separate continuous surfaces. On the other hand, in the Hough transform, if it is not easily affected by variations and the number of variations is small, the error region A1 and the regions on both sides thereof are detected as one flat line segment as shown in FIG. be able to.

Next, through steps S320 and S324, the end point of the detected line segment is determined as the boundary of the continuous surface, the coordinate information of the end point determined as the boundary of the continuous surface is converted into the sensor coordinate system, and the converted coordinate information Is stored in the memory.
When the measurement is completed for one scanning plane, the second scanning is performed by outputting a command signal to the driver 214 based on the scanning angle range and the scanning unit angle set for the second scanning process through step S340. Processing is executed.

  As a result, based on the command signal from the sensing processor 210 and the output signal from the encoder 218, the driver 214 rotates the rotation axis of the motor 216, and the two-dimensional distance measurement device 212 has a scanning unit angle of 10 around the zrs axis. Rotate by °. By the second scanning process, the orientation of the two-dimensional distance measuring device 212 changes by 10 ° around the zrs axis with respect to the previous state. In this state, the first scanning process is executed again through step S302. That is, a new scanning plane is formed at a position shifted by 10 ° around the zrs axis, and the first scanning process is performed on this scanning plane.

Here, since the two-dimensional distance measuring device 212 is attached to the front surface of the base body 10, the base body 10 is included in the scanning range, but in the range including the front of the leg wheel type robot 100 and the walking path. Since there are no obstructions, it can be said that a sufficient scanning range for performing the walking control of the leg-wheel type robot 100 can be secured.
When measurement is completed for all scanning planes, surface data is generated based on the coordinate information stored in the memory through step S336.

FIG. 31 is a diagram illustrating the determination result of the continuous surface.
As shown in FIG. 31, the plane data is generated by connecting line segments having similar inclinations and coordinates between adjacent scanning planes around the zrs axis. In the example of FIG. 31, for example, the line segment of the region (φ0, 2) corresponding to the first step plate on the scanning plane φ0 and the region (φ1, 2) corresponding to the first step plate on the scanning plane φ1. ) Is determined to constitute one continuous surface, surface data in which the coordinate information of the end points of the line segments is associated is generated for the continuous surface.

  Similarly, the line segment of the region (φ0, 2i (i is an integer greater than or equal to 2)) in the scan plane φ0 and the line segment of the region (φ1, 2i) in the scan plane φ1 represent one continuous plane, and the scan plane φ0 It is determined that the line segment of the region (φ0, 2j (j is an integer equal to or greater than 1) -1) and the line segment of the region (φ1, 2j-1) on the scanning plane φ1 constitute one continuous surface, and the plane data is Generated.

The surface data is output to the CPU 60 via the hub 76 and the communication I / F 64 through step S338.
When the surface data is input, the CPU 60 detects the staircase feature point based on the input surface data through step S402. In addition, the input surface data is analyzed, and for example, a continuous surface whose inclination is close to 0 is regarded as a horizontal surface, and it is determined that the leg-wheel type robot 100 can walk.

If it is determined that the surface is a walkable surface, the width of the staircase and the actual coordinates of the stair nose are calculated based on the detected feature points of the staircase through steps S404 to S410. The landing position of the leg tip is determined based on the real coordinates of the part.
Further, through steps S412 to S416, sensor signals are input from the leg tip sensors 22 and 24, respectively, and the distance to the kick plate and the positional relationship between the leg tip and the tread plate are calculated. Then, through steps S418 and S420, a motor command signal is generated based on the determined landing position and the calculated both distances, and the generated motor command signal is output to the drivers 44 and 54. As a result, the driving wheel 20 rotates and the rotary joints 14 to 18 are driven, and the leg-wheel type robot 100 gets over the stairs while keeping its posture properly. Depending on the situation, the stairs are avoided and stopped. Therefore, the adaptability to the stairs is high like the legged robot.

In addition, although the step is given as an example, the staircase where the step board is a continuous surface is given as an example, but the step can be accurately recognized even for a staircase where the step is not constant, a staircase without a kick plate, etc. The adaptability to the stairs of the leg wheel type robot 100 can be improved.
On the other hand, on a flat ground, the leg-wheel type robot 100 can move by wheel running. Therefore, the mobility on the flat ground is high like the wheel type robot.

  As described above, in this embodiment, the distance measuring sensor 212a that measures the distance to the measurement point on the object is provided, the distance measurement sensor 212a is scanned, and the distance measurement sensor can be measured for the measurement points that can be measured in the scanning range. The measurement result of 212a is acquired, the acquired measurement result is converted into the coordinates of the orthogonal coordinate system, and the line segment in the orthogonal coordinate system is detected by the Hough transform based on the converted coordinates of the at least two measurement points, and detected. Recognize continuous faces or boundaries of continuous faces based on line segments.

  Accordingly, since at least the planar shape of the object can be grasped as a continuous surface or a boundary between continuous surfaces, the posture control of a robot that requires complicated posture control, such as the legged robot or the legged wheel type robot 100, is possible. A suitable recognition result can be obtained. Further, since the line segment is detected by the Hough transform, when the object recognition is performed by the two-dimensional distance measuring device 212 using the distance measuring sensor 212a, there is a possibility that the recognition accuracy may be lowered due to a decrease in measurement resolution or a variation in measurement results. Can be reduced.

Furthermore, as compared with the least square method, robust detection can be performed for an edge that is difficult to detect.
Furthermore, in this embodiment, the continuous surface or the boundary of the continuous surface is recognized based on the coordinates of the end points of the detected line segment.
Thereby, the continuous surface or the boundary of the continuous surface can be recognized relatively accurately.

  Further, in the present embodiment, a yrs′-axis rotation mechanism including a motor 212c and the like that rotates the ranging sensor 212a around the yrs ′ axis, and a zrs axis including a motor 216 and the like that rotates the ranging sensor 212a around the zrs axis. A first scanning for obtaining a measurement result of the distance measuring sensor 212a for each scanning unit angle of the yrs 'axis rotating mechanism while rotating the distance measuring sensor 212a by the yrs' axis rotating mechanism. By performing the second scanning performed for each scanning unit angle of the zrs axis rotation mechanism while rotating the distance measuring sensor 212a, the measurement is performed for each scanning unit angle of the yrs' axis rotation mechanism and for each scanning unit angle of the zrs axis rotation mechanism. Get the result.

  As a result, the three-dimensional shape of the object can be grasped as a continuous surface or a boundary between the continuous surfaces, so that the posture control of a robot that requires complicated posture control, such as the legged robot or the leg-wheel type robot 100, is possible. A more suitable recognition result can be obtained. In addition, since a rotation mechanism that rotates the distance measuring sensor 212a is adopted, a space required for scanning is smaller than that of the moving mechanism, the scanning mechanism is simplified, and high-speed scanning is realized. Can do.

Furthermore, in this embodiment, the motor 216 and the encoder 218 and the two-dimensional distance measuring device 212 are arranged at a predetermined distance in the horizontal direction, and the rotational driving force of the driving rotary shaft is set to the pulley 220a, the belt 221 and the pulley 220b. The two-dimensional distance measuring device 212 is driven to rotate about the zrs axis.
As a result, there is no obstacle to scanning within the scanning angle range of the two-dimensional distance measuring device 212, so that accurate distance information can be obtained. Further, since the motor 216 and the encoder 218 and the two-dimensional distance measuring device 212 are arranged in the horizontal direction, the occupation ratio in the height direction of the three-dimensional distance measuring device 200 can be reduced.

Further, in the present embodiment, leg tip sensors 22 and 24 are provided, the stairs are recognized based on the distance measured by the leg tip sensors 22 and 24, and the motors 40 and 50 are controlled based on the recognition result.
Thereby, since the raising / lowering control of the leg part 12 is performed while recognizing the unknown staircase using the leg tip sensors 22 and 24, it is possible to realize higher adaptability to the unknown staircase than in the past. . In addition, since it can operate in an environment where people are active, it is suitable for home robots, personal robots, and the like that are used for acting with people.

Further, in the present embodiment, the three-dimensional distance measuring device 200 is provided on the front surface of the base body 10, and the leg tip sensors 22 and 24 are provided on the tip of the leg portion 12.
As a result, it is possible to detect an object existing on the movement path of the leg wheel type robot 100 with a wide field of view, and to accurately measure the distance between the drive wheel 20 and the staircase when moving up and down the stairs.

Further, in the present embodiment, the distance to the stair riser plate is calculated based on the measurement result of the front leg tip sensor 22, and the positions of the drive wheels 20 and the step board of the staircase are calculated based on the measurement result of the lower leg tip sensor 24. Calculate the relationship.
Thereby, since the characteristic more effective for the raising / lowering control of the leg part 12 can be detected among the characteristics of the staircase, higher adaptability can be realized for the unknown staircase.

  In the second embodiment, steps S302 and S340 correspond to the measurement result acquisition unit of the invention 12, 15 or 17, or the measurement result acquisition step of the invention 28, and step S306 includes the coordinate conversion unit of the invention 12, Alternatively, this corresponds to the coordinate conversion step of the invention 28. Step S310 corresponds to the line segment detecting means of the invention 12, 14 or 16, or the line segment detecting step of the invention 28, and steps S320 and S336 are the recognizing means of the invention 12, 14 or 16, or the invention 28. It corresponds to the recognition step.

  In the second embodiment, the yrs 'axis corresponds to the first scanning axis of the invention 17, the zrs axis corresponds to the second scanning axis of the invention 17, and the yrs' axis rotation mechanism is the invention. The zrs axis rotation mechanism corresponds to the second scanning means of the fifteenth or seventeenth aspect or the second rotating means of the seventeenth aspect. .

[Third Embodiment]
Next, a third embodiment of the present invention will be described with reference to the drawings. 32 and 33 are diagrams showing a third embodiment of the leg-wheel type robot, the object recognition apparatus, and the object recognition method according to the present invention.
This embodiment is different from the second embodiment in that the Hough transform is performed after connecting the measurement points with line segments in the orthogonal coordinate system. Hereinafter, only the parts different from the second embodiment will be described, and the same parts as those in the second embodiment will be denoted by the same reference numerals and the description thereof will be omitted.
First, an object recognition process executed by the three-dimensional distance measuring apparatus 200 will be described.

FIG. 32 is a flowchart showing object recognition processing executed by the three-dimensional distance measuring apparatus 200.
When the object recognition process is executed in the sensing processor 210, the process proceeds to step S308 through steps S300 to S306 as shown in FIG.
In step S308, based on the coordinate information converted in step S306, measurement points adjacent in the x-axis direction in the scanning plane coordinate system are connected with line segments, and the process proceeds to step S310 and the obtained line is changed. A line segment in the orthogonal coordinate system is detected by Hough transform based on the coordinate information of the point.

Then, after steps S320 and S324, the process proceeds to step S326, where it is determined whether or not the processing of steps S302 to S324 has been completed for all the scanning planes, and when it is determined that the processing has been completed (Yes) Through steps S336 and S338, a series of processing is completed.
On the other hand, when it is determined in step S326 that the processes in steps S302 to S324 are not completed for all scanning planes (No), the process proceeds to step S302 through step S340.

Next, the operation of the present embodiment will be described.
A case will be described in which a stairway exists on the movement path of the leg-wheel type robot 100 and the stairs are overcome. Since the second embodiment is different from the second embodiment in that a line segment is detected by Hough transform, only different portions will be described.
Through steps S308 and S310, measurement points are connected by line segments based on the converted coordinate information, and line segments in the orthogonal coordinate system are detected by Hough transform based on the coordinate information of the points on the obtained line. .

FIG. 33 is a graph showing measurement points, line segment connection results, and Hough transform results in an orthogonal coordinate system.
In the orthogonal coordinate system, each measurement point is represented as a set of a plurality of points along the contours of the kick board and the tread board as shown in FIG. In the example of FIG. 33 (a), in the region corresponding to the first step tread, some measurement points are distributed in a region deviating from the continuous surface. The measurement results vary due to the influence of the error area A1. The area A2 has a lower measurement resolution than the other areas.

When a line segment connection is made for this measurement result, each measurement point is connected by one line as shown in FIG. As a result, between the measurement points where no measurement point exists, the points on the line are interpolated.
When the Hough transform is performed on the connection result, as shown in FIG. 33 (c), a line segment along the outline of each kick board and each tread board is detected.

When the Hough transform is performed on the measurement result of FIG. 33A without connecting the line segments, as shown in FIG. 30B, the line segments along the contours of the treads are detected. The line segment along each kick plate cannot be detected.
As described above, in this embodiment, the distance measuring sensor 212a that measures the distance to the measurement point on the object is provided, the distance measurement sensor 212a is scanned, and the distance measurement sensor can be measured for the measurement points that can be measured in the scanning range. The measurement result of 212a is acquired, the acquired measurement result is converted into coordinates in an orthogonal coordinate system, the converted measurement points are connected by line segments, and orthogonality is obtained by Hough transform based on the coordinates of the points on the obtained line A line segment in the coordinate system is detected, and a continuous surface or a boundary of the continuous surface is recognized based on the detected line segment.

  Accordingly, since at least a planar shape of the object can be grasped as a continuous surface on the object or a boundary between the continuous surfaces, a robot that requires complicated posture control, such as the legged robot or the leg wheel type robot 100. A recognition result suitable for posture control can be obtained. Further, since the line segment is detected by the Hough transform, when the object recognition is performed by the two-dimensional distance measuring device 212 using the distance measuring sensor 212a, there is a possibility that the recognition accuracy may be lowered due to a decrease in measurement resolution or a variation in measurement results. Can be reduced. In addition, since line segments are detected based on the coordinates of points on the line obtained by connecting the measurement points with line segments, relatively accurate recognition results can be obtained even if measurement resolution decreases or measurement results vary. The possibility that the recognition accuracy is lowered can be further reduced.

Furthermore, as compared with the least square method, robust detection can be performed for an edge that is difficult to detect.
In the third embodiment, steps S302 and S332 correspond to the measurement result acquisition means of the invention 13 or the measurement result acquisition step of the invention 29, and the step S306 corresponds to the coordinate conversion means of the invention 13 or the invention 29. Corresponding to the coordinate conversion step, step S310 corresponds to the line segment detection means of the invention 13 or the line segment detection step of the invention 29. Steps S320 and S328 correspond to the recognition means of the invention 13 or the recognition step of the invention 29.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described with reference to the drawings. 34 to 41 are diagrams showing a fourth embodiment of the leg-wheel type robot, the object recognition apparatus, and the object recognition method according to the present invention.
The present embodiment is different from the second embodiment in that the boundary of the continuous surface is recognized based on the measurement result of the distance measuring sensor 212a and an image acquired from the camera 222 (hereinafter referred to as a camera image). Is different. Hereinafter, only the parts different from the second embodiment will be described, and the same parts as those in the second embodiment will be denoted by the same reference numerals and the description thereof will be omitted.

First, the external structure of the three-dimensional distance measuring apparatus 200 will be described.
The camera 222 faces the negative direction of the zrs axis, and can capture images of the feet and surroundings of the leg wheel type robot 100. As in the sensor coordinate system, the coordinate system of the camera 222 (hereinafter referred to as the camera coordinate system) has the same direction as the xrs axis, yrs axis, and zrs axis as the xca axis, yca axis, and zca axis, respectively. Have different origin positions. That is, the camera 222 is arranged so that the xrs-yrs plane in the sensor coordinate system and the xca-yca plane in the camera coordinate system are parallel. The xrs-zrs plane and the xca-zca plane, and the yrs-zrs plane and the yca-zca plane are also in a parallel relationship.

Next, the control structure of the three-dimensional distance measuring apparatus 200 will be described.
The sensing processor 210 further executes processing for recognizing the boundary of the continuous surface based on the measurement result of the distance measuring sensor 212a and the camera image.
Next, the principle of object recognition using the camera 222 and the three-dimensional distance measuring device 200 will be described.

FIG. 34 is a diagram for explaining the principle of object recognition using the camera 222 and the three-dimensional distance measuring apparatus 200.
First, as shown in FIG. 34, images of the feet and surroundings of the leg wheel type robot 100 are taken by the camera 222, and line segments are detected from the camera images.
Next, the boundary of the continuous surface is determined as a sensor feature point from the coordinates of the measurement point measured for each scanning plane by the three-dimensional distance measuring apparatus 200, and the sensor feature point is projected onto the camera image by coordinate conversion.

And the boundary of a continuous surface is recognized based on the positional relationship of the line segment detected from the camera image (henceforth a line segment of a camera image) and the projection point of a sensor feature point.
Accordingly, the recognition accuracy can be improved as compared with the case where the recognition is performed based only on the sensor feature points obtained by the three-dimensional distance measuring apparatus 200 and the case where the recognition is performed based only on the camera image.

Next, an object recognition process executed by the three-dimensional distance measuring apparatus 200 will be described.
FIG. 35 is a flowchart showing object recognition processing executed by the three-dimensional distance measuring apparatus 200.
When the object recognition process is executed in the sensing processor 210, the process first proceeds to step S150 as shown in FIG.

  In step S150, an image is acquired from the camera 222, the process proceeds to step S152, distortion correction processing is executed on the camera image, and the process proceeds to step S154, from which the distortion-corrected camera image is subjected to Sobel, Canny filter, and the like. In step S156, an edge extraction process for extracting edges is performed, and a line segment is detected from the camera image from which the edges have been extracted by Hough transform.

Subsequently, the process proceeds to step S324 through steps S300 to S320, and the coordinate information of the end point determined as the boundary of the continuous surface is converted into the sensor coordinate system, and the converted coordinate information is stored in the memory, and the process proceeds to step S326. To do.
In step S326, it is determined whether or not the processing in steps S302 to S324 has been completed for all scanning planes corresponding to the scanning angle range and scanning unit angle of the second scanning processing, and when it is determined that the processing has been completed (Yes) ) Proceeds to step S328.

In step S328, based on the coordinate information stored in the memory, the end point determined as the boundary of the continuous surface is used as the sensor feature point, and the sensor feature point is projected onto the camera image by coordinate conversion.
FIG. 36 is a diagram illustrating a sensor coordinate system, a camera coordinate system, and a coordinate system of the image sensor surface of the camera 222.

Sensor feature points can be projected onto a camera image using a general pinhole model.
The coordinate system of the image sensor surface of the camera 222 is Σ cm, the relative position between the distance measuring sensor 212a and the camera 222 is r = (rx, ry, rz), the focal length of the lens of the camera 222 is f, and the effective pixel width of the image sensor Is W and the effective pixel height of the image sensor is H, P (xrs1, yrs1, zrs1) rs = (xrs1-rx, yrs1-ry, zrs1-rz) ca in the sensor coordinate system is shown in FIG. As shown in (b), the image can be projected onto a coordinate P ′ in the coordinate system of the imaging element surface. The coordinate P ′ can be obtained by the following equation (5).

  36 and the above equation (5), the coordinates (a, b, c) in the sensor coordinate system Σrs, the camera coordinate system Σca, and the coordinate system Σcm of the image sensor surface are respectively represented by (a, b, c) rs, (A, b, c) ca, (a, b, c) cm.

  Next, as shown in FIG. 35, the process proceeds to step S330, and in the camera image, for each line segment of the camera image, the line segment and the sensor feature points existing within a predetermined distance from the straight line obtained by extending the line segment. And the process moves to step S332 to group the line segments associated with the same sensor feature point, and the process moves to step S334 to determine the continuous surface based on the coordinates of the end points of the line segments belonging to the same group. Determine the boundary line.

FIG. 37 is a diagram for explaining a case in which line segments of camera images and sensor feature points are associated, grouped, and boundary lines are determined.
As shown in FIG. 37A, it is assumed that two line segments l1 and l2 having close inclinations are detected from the camera image, and four projection points P1 to P4 are obtained around the line segments l1 and l2. In this case, since projection points P2, P3, and P4 exist within a predetermined distance from a straight line obtained by extending the line segment l1, the projection points P2, P3, and P4 with respect to the line segment l1 as shown in FIG. Are associated. Further, since the projection points P1, P2, and P3 exist within a predetermined distance from the straight line obtained by extending the line segment l2, the projection points P1, P2, and P3 are associated with the line segment l2.

Next, since the projection points P2 and P3 are associated in common with the line segments l1 and l2, the line segments l1 and l2 are grouped as one group.
Then, based on the coordinates of the end points P5 and P6 of the line segment l1 and the end points P7 and P8 of the line segment l2 belonging to the same group, as shown in FIG. The determined straight line is determined as the boundary line of the continuous surface.

As a result, due to the influence of contrast or the like, even though a plurality of line segments should be detected from the camera image as actually one line segment, a plurality of line segments are set to 1 based on the correspondence with sensor feature points. It can be grouped as one line segment and the boundary line of the continuous surface can be determined.
Next, as shown in FIG. 35, the process proceeds to step S337, where boundary data is generated based on the information regarding the straight line determined as the boundary line of the continuous surface, and the process proceeds to step S339, where the hub 76 and the communication I / F 64 are processed. Then, the generated boundary data is output to the CPU 60, and the series of processes is terminated.

On the other hand, when it is determined in step S326 that the processes in steps S302 to S324 are not completed for all scanning planes (No), the process proceeds to step S302 through step S340.
Next, the elevation control process will be described.
FIG. 38 is a flowchart showing the elevation control process.

When the elevation control process is executed by the CPU 60, first, the process proceeds to step S401 as shown in FIG.
In step S401, boundary data is input from the three-dimensional distance measuring apparatus 200, and the process proceeds to step S402. Based on the input boundary data, the coordinates of the camera coordinate system are converted to the coordinates of the global coordinate system, and A point on the boundary line is detected as a feature point of the staircase.

Next, after steps S402 to S420, the process proceeds to step S422, where it is determined whether the leg tip has landed on the tread. If it is determined that the leg tip has landed (Yes), the series of processing is terminated. To return to the original process.
On the other hand, when it is determined in step S422 that the leg tip does not land (No), the process proceeds to step S412.

Next, the operation of the present embodiment will be described.
A case will be described in which a stairway exists on the movement path of the leg-wheel type robot 100 and the stairs are overcome. Since the second embodiment is different from the second embodiment in that the boundary of the continuous surface is recognized based on the measurement result of the distance measuring sensor 212a and the camera image, only different portions will be described.
FIG. 39 is a diagram illustrating the processing result of the camera image.

  In the sensing processor 210, first, an image is acquired from the camera 222 through step S150. For example, assume that an image as shown in FIG. Next, through step S152, distortion correction processing is performed on the camera image, and an image with corrected distortion is obtained as shown in FIG. Next, through step S154, edge extraction processing is executed on the camera image whose distortion has been corrected, and an image in which only edges are extracted is obtained as shown in FIG. Then, through step S156, a line segment is detected from the edge-extracted camera image. As a result, six line segments are obtained as shown in FIG.

Next, through steps S300 to S326, measurement results by the first scanning process are obtained for all scanning planes.
When the measurement is completed for all the scanning planes, the sensor feature points are projected onto the camera image through coordinate transformation based on the coordinate information stored in the memory through step S328.
FIG. 40 is a diagram illustrating determination results of continuous surfaces.

FIG. 41 is a diagram illustrating a result of projecting sensor feature points onto a camera image.
For the scanning plane φ0, as shown in FIG. 40, (1) the intersection of the region (φ0, 0) corresponding to the floor surface and the region (φ0, 1) corresponding to the first stage kick plate, (2) The intersection of the region (φ0, 1) and the region (φ0, 2) corresponding to the first step plate, (3) the region (φ0, 2) and the region (φ0, 3) corresponding to the second step kick plate And four intersections of (4) the intersection of the region (φ0, 3) and the region (φ0, 4) corresponding to the second step board are determined as sensor feature points. Therefore, as shown in FIG. 41, the four sensor feature points are projected onto the camera image as projection points on the scanning plane φ0 that extends from the upper right corner to the lower left corner.

  For the scanning plane φ1, as shown in FIG. 40, (1) the intersection of the region (φ1, 0) corresponding to the floor surface and the region (φ1, 1) corresponding to the first-stage kick plate, (2) The intersection of the region (φ1, 1) and the region (φ1, 2) corresponding to the first step board, (3) the region (φ1, 2) and the region (φ1, 3) corresponding to the second step kick plate And four intersections of (4) the intersection of the region (φ1, 3) and the region (φ1, 4) corresponding to the second step board are determined as sensor feature points. Accordingly, as shown in FIG. 41, the four sensor feature points are projected onto the camera image as projection points on the scanning plane φ1 that extends from the position directly above the center to the position directly below the center.

  For the scanning plane φ2, as shown in FIG. 40, (1) the intersection of the region (φ2, 0) corresponding to the floor surface and the region (φ2, 1) corresponding to the first stage kick plate, (2) The intersection of the region (φ2, 1) and the region (φ2, 2) corresponding to the first step plate, (3) The region (φ2, 2) and the region (φ2, 3) corresponding to the second step kick plate And four intersections of (4) the intersection of the area (φ2, 3) and the area (φ2, 4) corresponding to the second step board are determined as sensor feature points. Accordingly, as shown in FIG. 41, the four sensor feature points are projected onto the camera image as projection points on the scanning plane φ2 that extends from the center upper left to the center lower right.

  Next, through steps S330 to S334, in the camera image, the line segment of the camera image is associated with the sensor feature point, the line segments associated with the same sensor feature point are grouped, and the line segments belonging to the same group are grouped. The boundary line of the continuous surface is determined by linear approximation based on the coordinates of the end points. In the example of FIG. 41, two straight lines are determined as the boundary line of the continuous surface from the positional relationship between the line segment of the camera image and each projection point.

Then, through steps S337 and S339, boundary data is generated based on the information about the straight line determined as the boundary line of the continuous surface, and the generated boundary data is output to the CPU 60.
When the boundary data is input, the CPU 60 detects the feature points of the stairs based on the input boundary data through step S402. Further, the input boundary data is analyzed, and for example, a continuous surface having an inclination close to 0 is regarded as a horizontal surface, and it is determined that the leg-wheel type robot 100 is a surface on which walking is possible.

  Thus, in this embodiment, the distance measuring sensor 212a that measures the distance to the measurement point on the object, and the camera 222 that captures an image including the measurement point that can be measured in the scanning range of the distance measuring sensor 212a. The distance measurement sensor 212a is scanned, the measurement result of the distance measurement sensor 212a is obtained for the measurement points that can be measured in the scanning range, the sensor feature point is detected based on the obtained measurement result, and the image is taken from the camera 222. , The line segment is detected from the camera image, and the boundary of the continuous surface is recognized based on the line segment of the detected camera image and the sensor feature point.

  Thereby, in addition to the distance measurement sensor 212a, a feature on the object is detected using a camera 222 of a different system, and the boundary of the continuous surface is recognized based on the two detection results. The shortcomings of the system based on 212a can be compensated for by the system based on the camera 222, and the possibility of a decrease in recognition accuracy can be reduced when object recognition is performed by the two-dimensional distance measuring device 212 using the distance measuring sensor 212a. . In addition, since it is not necessary to increase the number of scans in the second scanning process, the measurement time can be shortened.

Further, in the present embodiment, the distance measurement sensor 212a is scanned, the measurement result of the distance measurement sensor 212a is obtained for the measurement points that can be measured in the scanning range, and the obtained measurement result is converted into the coordinates of the orthogonal coordinate system. The line segment in the orthogonal coordinate system is detected by the Hough transform based on the converted coordinates of at least two measurement points, and the sensor feature point is detected based on the detected line segment.
This makes it possible to grasp at least the planar shape of an object as a boundary between continuous surfaces, which is suitable for posture control of robots that require complex posture control, such as legged robots and leg-wheel type robots 100. A recognition result can be obtained. Further, since the line segment is detected by the Hough transform, when the object recognition is performed by the two-dimensional distance measuring device 212 using the distance measuring sensor 212a, there is a possibility that the recognition accuracy may be lowered due to a decrease in measurement resolution or a variation in measurement results. Can be reduced.

Furthermore, as compared with the least square method, robust detection can be performed for an edge that is difficult to detect.
Furthermore, in this embodiment, sensor feature points are detected based on the coordinates of the end points of the detected line segment.
Thereby, the boundary of a continuous surface can be recognized comparatively correctly.

Furthermore, in this embodiment, a line segment is detected from the camera image, and the boundary of the continuous surface is recognized in the camera image based on the positional relationship between the line segment of the camera image and the sensor feature point.
Thereby, possibility that recognition accuracy will fall can further be reduced.
Furthermore, in this embodiment, for each line segment of the camera image, the line segment is associated with a sensor feature point existing within a predetermined distance from a straight line obtained by extending the line segment, and the same sensor feature point corresponds The attached line segments are grouped, and the boundary line of the continuous surface is determined based on the coordinates of the end points of the line segments belonging to the same group.

As a result, due to the influence of contrast or the like, even though a plurality of line segments should be detected from the camera image as actually one line segment, a plurality of line segments are set to 1 based on the correspondence with sensor feature points. Since it is grouped as one line segment and the boundary line of the continuous surface is determined, the possibility that the recognition accuracy is lowered can be further reduced.
In the fourth embodiment, the camera 222 corresponds to the imaging means of the invention 18, 25 or 27, and the yrs' axis rotation mechanism is the first scanning means of the invention 22 or 23 or the first rotation of the invention 23. The zrs axis rotation mechanism corresponds to the second scanning means of the invention 22 or 23 or the second rotation means of the invention 23. Step S150 corresponds to the imaging step of the invention 30, steps S152 to S156 correspond to the second feature detection means of the invention 18, 19 or 25, or the second feature detection step of the invention 30, and step S156 This corresponds to the image line segment detecting means of the invention 25 or 26.

  In the fourth embodiment, steps S306, S310, and S320 correspond to the first feature detecting means of the invention 18, 19 or 25, or the first feature detecting step of the invention 30, and steps S302 and S340 are This corresponds to the measurement result acquisition means of the invention 18, 19, 22, 23 or 25, or the measurement result acquisition step of the invention 30. Step S306 corresponds to the coordinate transformation means of the invention 19, step S310 corresponds to the line segment detection means of the invention 19, and step S334 corresponds to the recognition means of the invention 18, 19, 25 or 26, or the invention 30. This corresponds to the recognition step.

  In the fourth embodiment, the yrs' axis corresponds to the first scanning axis of the invention 23, and the zrs axis corresponds to the second scanning axis of the invention 23.

[Fifth Embodiment]
Next, a fifth embodiment of the present invention will be described with reference to the drawings. FIG. 42 is a diagram showing a fifth embodiment of the leg-wheel robot, object recognition device, and object recognition method according to the present invention.
This embodiment differs from the fourth embodiment in that the Hough transform is performed after connecting the measurement points with line segments in the orthogonal coordinate system. Hereinafter, only the parts different from the fourth embodiment will be described, and the same parts as those in the fourth embodiment will be denoted by the same reference numerals and the description thereof will be omitted.
First, an object recognition process executed by the three-dimensional distance measuring apparatus 200 will be described.

FIG. 42 is a flowchart showing object recognition processing executed by the three-dimensional distance measuring apparatus 200.
When the object recognition process is executed in the sensing processor 210, as shown in FIG. 42, the process proceeds to step S308 through steps S150 to S306.
In step S308, based on the coordinate information converted in step S306, measurement points adjacent in the x-axis direction in the scanning plane coordinate system are connected with line segments, and the process proceeds to step S310 and the obtained line is changed. A line segment in the orthogonal coordinate system is detected by Hough transform based on the coordinate information of the point.

Then, after steps S320 and S324, the process proceeds to step S326, where it is determined whether or not the processing of steps S302 to S324 has been completed for all the scanning planes, and when it is determined that the processing has been completed (Yes) Through steps S328 to S339, the series of processes is terminated.
On the other hand, when it is determined in step S326 that the processes in steps S302 to S324 are not completed for all scanning planes (No), the process proceeds to step S302 through step S340.

Next, the operation of the present embodiment will be described.
A case will be described in which a stairway exists on the movement path of the leg-wheel type robot 100 and the stairs are overcome. Since the fourth embodiment is different from the fourth embodiment in that a line segment is detected by Hough transform, only different portions will be described.
Through steps S308 and S310, measurement points are connected by line segments based on the converted coordinate information, and line segments in the orthogonal coordinate system are detected by Hough transform based on the coordinate information of the points on the obtained line. .

  In the orthogonal coordinate system, each measurement point is represented as a set of a plurality of points along the contours of the kick board and the tread board as shown in FIG. In the example of FIG. 33 (a), in the region corresponding to the first step tread, some measurement points are distributed in a region deviating from the continuous surface. The measurement results vary due to the influence of the error area A1. The area A2 has a lower measurement resolution than the other areas.

When a line segment connection is made for this measurement result, each measurement point is connected by one line as shown in FIG. As a result, between the measurement points where no measurement point exists, the points on the line are interpolated.
When the Hough transform is performed on the connection result, as shown in FIG. 33 (c), a line segment along the outline of each kick board and each tread board is detected.

When the Hough transform is performed on the measurement result of FIG. 33A without connecting the line segments, as shown in FIG. 30B, the line segments along the contours of the treads are detected. The line segment along each kick plate cannot be detected.
As described above, in this embodiment, the distance measuring sensor 212a that measures the distance to the measurement point on the object is provided, the distance measurement sensor 212a is scanned, and the distance measurement sensor can be measured for the measurement points that can be measured in the scanning range. The measurement result of 212a is acquired, the acquired measurement result is converted into coordinates in an orthogonal coordinate system, the converted measurement points are connected by line segments, and orthogonality is obtained by Hough transform based on the coordinates of the points on the obtained line A line segment in the coordinate system is detected, and the boundary of the continuous surface is recognized based on the detected line segment.

  This makes it possible to grasp at least the planar shape of an object as a boundary between continuous surfaces, which is suitable for posture control of robots that require complex posture control, such as legged robots and leg-wheel type robots 100. A recognition result can be obtained. Further, since the line segment is detected by the Hough transform, when the object recognition is performed by the two-dimensional distance measuring device 212 using the distance measuring sensor 212a, there is a possibility that the recognition accuracy may be lowered due to a decrease in measurement resolution or a variation in measurement results. Can be reduced. In addition, since line segments are detected based on the coordinates of points on the line obtained by connecting the measurement points with line segments, relatively accurate recognition results can be obtained even if measurement resolution decreases or measurement results vary. The possibility that the recognition accuracy is lowered can be further reduced.

Furthermore, as compared with the least square method, robust detection can be performed for an edge that is difficult to detect.
In the fifth embodiment, steps S152 to S156 correspond to the second feature detection unit of the invention 20, steps S306 to S310, S320 correspond to the first feature detection unit of the invention 20, and steps S302, S340 corresponds to the measurement result acquisition means of the twentieth aspect. Step S306 corresponds to the coordinate conversion means of the twentieth aspect, step S308 corresponds to the interpolating means between measurement points of the twentieth aspect, step S310 corresponds to the line segment detection means of the twentieth aspect, and step S334 corresponds to the step S334. This corresponds to the recognition means of the twentieth aspect.
[Sixth Embodiment]
Next, a sixth embodiment of the present invention will be described with reference to the drawings. FIGS. 43 to 46 are views showing a sixth embodiment of the leg-wheel type robot, the object recognition apparatus, and the object recognition method according to the present invention.

  Compared to the fourth embodiment, the present embodiment calculates the inclination at each measurement point in the orthogonal coordinate system, calculates the appearance frequency of each inclination, the calculated appearance frequency and the coordinates of each measurement point The point of recognizing the boundary of the continuous surface is different. Hereinafter, only the parts different from the fourth embodiment will be described, and the same parts as those in the fourth embodiment will be denoted by the same reference numerals and the description thereof will be omitted.

First, an object recognition process executed by the three-dimensional distance measuring apparatus 200 will be described.
FIG. 43 is a flowchart showing object recognition processing executed by the three-dimensional distance measuring apparatus 200.
When the object recognition process is executed in the sensing processor 210, as shown in FIG. 43, the process proceeds to step S408 through steps S150 to S306.

In step S408, the inclination at each measurement point in the orthogonal coordinate system is calculated based on the coordinate information converted in step S306.
FIG. 44 is a diagram illustrating an example of calculating the inclination. In the figure, the x-axis and z-axis indicate axes in the scanning plane coordinate system, and are separate from the axes in the sensor coordinate system and the camera coordinate system.
The inclination at the measurement point is shown in FIG. 44 (a) based on the coordinates of the measurement point and the coordinates of a predetermined number of measurement points adjacent in the x-axis direction for each measurement point in the scanning plane coordinate system. As shown, it can be calculated by the least square method.

As shown in FIG. 44 (a), a regression line is approximated to a predetermined number of measurement points before and after the measurement points (white circles in FIG. 44 (a)) to be calculated by the least square method. The inclination is the inclination at the target measurement point. The least squares method is less affected by data variations but has a relatively large amount of calculation.
As another method, for each measurement point, an inclination can be calculated based on a difference value between coordinates of two measurement points before and after a predetermined number of other measurement points.

As shown in FIG. 44 (b), a first difference value that is a difference value between z coordinates of two measurement points before and after (for example, if the z coordinate of the measurement point of interest is z _i , z _{i + 2} −z _{i -2)} calculates the second difference value is a difference value between the x-coordinate of the front and rear two measurement points (e.g., the x-coordinate of the measurement point of interest When _{x i, x i + 2 -x} i-2 ) And the inclination (first difference value / second difference value) at the measurement point of interest is obtained from these calculation results. In this method, the influence of data variation is greater than that in the least squares method, but since the calculation requires only simple subtraction and division, the slope can be calculated faster than in the least squares method.

Next, as shown in FIG. 43, the process proceeds to step S410, and the appearance frequency of each inclination with respect to the total number of inclinations calculated in step S408 is calculated. For example, the number of measurement points at each inclination with respect to the total number of measurement points is calculated as the appearance frequency.
Next, the process proceeds to step S412, where the appearance frequency of the unprocessed slope is selected from the appearance frequencies of the respective slopes calculated in step S410, and the process proceeds to step S414, where the selected appearance frequency and a preset threshold value are selected. Are determined, and it is determined whether or not the selected appearance frequency is equal to or higher than the threshold value. When it is determined that the selected appearance frequency is equal to or higher than the threshold value (Yes), the process proceeds to step S416.

In step S416, based on the coordinate information of the measurement points having the inclination related to the selected appearance frequency and the inclination of the predetermined range, it is determined that the region including the measurement points having continuous coordinates is a continuous surface. In a region determined to be a continuous surface, a measurement point whose inclination changes abruptly is determined as a boundary of the continuous surface.
Next, the process proceeds to step S418, where the coordinate information of the measurement point determined as the boundary of the continuous surface is converted into the sensor coordinate system, the converted coordinate information is stored in the memory, and the process proceeds to step S420.

In step S420, it is determined whether or not the processes in steps S414 to S418 and S434 have been completed for all inclinations. If it is determined that the process has been completed (Yes), the process proceeds to step S326.
In step S326, it is determined whether or not the processing in steps S302 to S420 has been completed for all the scanning planes. When it is determined that the processing has been completed (Yes), the series of processing is terminated through steps S328 to S339. To do.

On the other hand, when it is determined in step S326 that the processing of steps S302 to S420 is not completed for all scanning planes (No), the process proceeds to step S302 via step S340.
On the other hand, when it is determined in step S420 that the processes in steps S414 to S418 and S434 are not completed for all inclinations (No), the process proceeds to step S412.

On the other hand, when it is determined in step S414 that the selected appearance frequency is less than the threshold value (No), the process proceeds to step S434, and the coordinate information of the measurement point having the inclination related to the selected appearance frequency is excluded as measurement noise. Then, the process proceeds to step S420.
Next, the operation of the present embodiment will be described.
A case will be described in which a stairway exists on the movement path of the leg-wheel type robot 100 and the stairs are overcome. Since the fourth embodiment is different from the fourth embodiment in that the boundary of the continuous surface is determined based on the appearance frequency of the inclination, only different portions will be described.

First, through step S408, the inclination at each measurement point is calculated based on the converted coordinate information.
FIG. 45 is a diagram illustrating an example of inclinations in the x-axis direction and the z-axis direction calculated by the least square method.
Here, the slope at each measurement point is calculated by the least square method. Here, when the least square method is used, as shown in FIGS. 45A and 45B, the inclination in the x-axis direction and the z-axis direction with respect to a plurality of measurement points to which the least square method is applied. May be different from the slope. Therefore, as shown in the following formulas (6) and (7), the least square method calculation is performed using two linear equations for obtaining inclinations in the x-axis direction and the z-axis direction.

z = a _x · x + b _x (6)
x = a _z · z + b _z (7)

Then, a _x and b _x in the above equation (6) are calculated by the following equation (8), and a _z and b _z in the above equation (7) are calculated by the following equation (9).

When a _x and b _x and a _z and b _z are calculated, the distances between the straight lines of the above equations (6) and (7) and the respective measurement points used for the least square calculation are calculated. and calculates a residual h _x and h _z, calculates the square sum of the residual h _x wherein for each measuring point, and a sum of squares of residuals h _z (following formula (10)).

When the square sum of the residual h _{x and} the square sum of the residual h _z are calculated, the straight line with the smaller value is compared as the correct straight line, and the calculation target is calculated based on the slope of this straight line. Find the slope at the measurement point. Specifically, _if the square sum of the residual h _x is smaller, “a = a _x , b = b _x ”. _If the square sum of the residual h _z is smaller, “a = 1 / _az”. , B = 1 / b _z ”.

  Next, through steps S410 to S414, the appearance frequency of each inclination is calculated, the appearance frequency of the undetermined inclination is selected, and it is determined whether or not the selected appearance frequency is equal to or greater than a threshold value. At this time, if it is equal to or greater than the threshold value, the boundary of the continuous surface is determined through step S416 based on the selected inclination of the appearance frequency and the coordinate information of the measurement point having the predetermined range of inclination.

FIG. 46 is a diagram illustrating an example of the appearance frequency of the inclination with respect to a certain scanning plane.
For example, it is assumed that the appearance frequency as shown in FIG. 46 is obtained. In the example of FIG. 46, the appearance frequency near the inclination of 0 is relatively high, and if the coordinates of the measurement points having these inclinations are continuous, the region including the continuous measurement points is a continuous surface. It is determined. On the movement path of the leg-wheel type robot 100, there is a staircase having a constant step and a tread plate as a continuous surface. Therefore, the horizontal plane corresponding to the tread plate has a series of measurement points with zero inclination and substantially zero. Appear as coordinates. In this case, it can be estimated that there is a horizontal plane there.

  And in the area | region determined to be a continuous surface, the measurement point in which inclination changes rapidly is determined as a boundary of a continuous surface. In the example of FIG. 40, for a certain scanning plane, (1) an intersection of an area corresponding to the floor surface and an area corresponding to the first-stage kick board, (2) an area corresponding to the area and the first-stage tread board, and The four intersections of the intersection of (3) the area and the area corresponding to the second-stage kick board, and (4) the intersection of the area and the area corresponding to the second-stage tread are Determined.

Next, through step S418, the coordinate information of the measurement point determined as the boundary of the continuous surface is converted into the sensor coordinate system, and the converted coordinate information is stored in the memory.
On the other hand, if it is less than the threshold value, the coordinate information of the measurement point is excluded as measurement noise through step S434.
The processes in steps S414 to S418 and S434 are performed for all inclinations.

  As described above, in this embodiment, the distance measuring sensor 212a that measures the distance to the measurement point on the object is provided, the distance measurement sensor 212a is scanned, and the distance measurement sensor can be measured for the measurement points that can be measured in the scanning range. The measurement result of 212a is acquired, the acquired measurement result is converted into the coordinates of the orthogonal coordinate system, and for each converted measurement point, the orthogonal coordinate system is based on the coordinates of the measurement point and the coordinates of the surrounding measurement points. The slope at the measurement point is calculated, the appearance frequency of each slope with respect to the calculated total number of slopes is calculated, and the boundary of the continuous surface is recognized based on the calculated appearance frequency and the converted coordinates of each measurement point.

  This makes it possible to grasp at least the planar shape of an object as a boundary between continuous surfaces, which is suitable for posture control of robots that require complex posture control, such as legged robots and leg-wheel type robots 100. A recognition result can be obtained. Further, since the boundary of the continuous surface is recognized based on the appearance frequency of the inclination at the measurement point and the coordinates of each measurement point, the recognition is performed when the object is recognized by the two-dimensional distance measuring device 212 using the distance measuring sensor 212a. The possibility that the accuracy is lowered can be reduced.

  In the sixth embodiment, steps S152 to S156 correspond to the second feature detection means of the invention 21, steps S306 and S408 to S416 correspond to the first feature detection means of the invention 21, and steps S302, S340 corresponds to the measurement result acquisition means of the invention 21. Step S306 corresponds to the coordinate conversion means of the invention 21, step S408 corresponds to the inclination calculation means of the invention 21, step S410 corresponds to the appearance frequency calculation means of the invention 21, and step S334 corresponds to the invention. This corresponds to 21 recognition means.

In the second and third embodiments, the configuration is such that the continuous surface on the object or the boundary of the continuous surface is recognized. However, the present invention is not limited to this. It can also be configured to recognize.
In the third and fifth embodiments, the adjacent measurement points are connected by line segments. However, the present invention is not limited to this. May be connected, or the measurement points may be approximated by a straight line, a line segment, a multi-order curve, or other curves. In this case, the measurement points do not necessarily have to be located on the line, and adjacent measurement points need not be targeted.

Further, in the third and fifth embodiments, the line segment is detected by the Hough transform based on the coordinates of the point on the line obtained by the line segment connection. However, the present invention is not limited to this. A line segment may be detected by Hough transform based on the coordinates of a point existing within a predetermined distance from the given line.
In the fourth to sixth embodiments, the three-dimensional distance measuring device 200 rotates the distance measuring sensor 212a around the yrs' axis and rotates the two-dimensional distance measuring device 212 around the zrs axis. However, the present invention is not limited to this, and includes a plurality of distance measuring sensors 212a and a plurality of rotation mechanisms that respectively rotate the distance measuring sensors 212a around a scanning axis orthogonal to the measurement direction of the distance measuring sensor 212a. The distance measuring sensor 212a may be arranged around the zrs axis.

As a result, as in the fourth to sixth embodiments, the three-dimensional shape of the object can be grasped as the boundary of the continuous surface, so that it is complicated as in the legged robot and legged wheel type robot 100. A recognition result suitable for posture control of a robot that requires posture control can be obtained.
In the fourth to sixth embodiments, the line segment is detected from the camera image by the Hough transform. However, the present invention is not limited to this, and the line segment is detected by the following detection method. It can also be configured.

As a first detection method, the edge extraction process is executed a plurality of times while changing the parameters of the edge extraction process, and a line segment is detected by Hough transform from each edge-extracted camera image. And the boundary of a continuous surface is recognized based on all the detected line segments. Thereby, possibility that recognition accuracy will fall can further be reduced.
As a second detection method, a plurality of images are acquired from the camera 222 by changing the shooting conditions of the camera 222 such as a shutter speed and an aperture, and distortion correction processing and edge extraction processing are respectively performed on the camera images. A line segment is detected by Hough transform from each camera image obtained by edge extraction. And the boundary of a continuous surface is recognized based on all the detected line segments. Thereby, possibility that recognition accuracy will fall can further be reduced.

In the fourth to sixth embodiments, the configuration is such that the boundary of the continuous surface on the object is recognized. However, the present invention is not limited to this. It can also be configured to recognize.
Moreover, in the said 4th thru | or 6th Embodiment, although comprised so that boundary data might be produced | generated based on the information regarding the straight line determined as the boundary line of a continuous surface, it is not restricted to this, For example, of a continuous surface It can also be configured to generate the surface data based on the information regarding the straight line determined as the boundary line and the coordinate information of the sensor feature point.

  Since the line segment connecting the sensor feature points determined as the boundary of the continuous surface is an intersection line where the continuous surface and the scanning plane intersect, generation of the surface data includes, for example, a line segment connecting the sensor feature points in a certain scanning plane, In the scanning plane adjacent to the z-axis, those having inclinations and coordinates with a line segment connecting sensor feature points within a predetermined range are determined as continuous surfaces, and correspond to the straight line determined as the boundary line between these line segments and the continuous surface. This is performed by associating coordinate information or connecting them using a known interpolation method. For example, since a continuous surface having an inclination close to 0 can be regarded as a horizontal surface, it can be determined that the surface is a walking surface.

  In the fourth to sixth embodiments, the sensor feature points are projected onto the camera image by coordinate transformation. However, the present invention is not limited to this, and the line segment of the camera image is a plane of the scanning plane coordinate system. The sensor feature point and the line segment of the camera image may be projected onto a plane or space of another coordinate system. That is, the coordinate system for determining the positional relationship between the line segment of the camera image and the sensor feature point can be arbitrary.

  In the fourth to sixth embodiments, the line segment is detected from the camera image and the boundary of the continuous surface is recognized based on the detected line segment. However, the present invention is not limited to this. Detect points, straight lines, multi-dimensional curves, circles, ellipses and other curves, planes, curved surfaces and other surfaces, cubes, spheres and other three-dimensional features from the camera image, and continuous surfaces based on the detected features It is also possible to configure so as to recognize the boundary.

  In the fourth to sixth embodiments, the sensor feature point is detected based on the measurement result of the distance measuring sensor 212a, and the boundary of the continuous surface is recognized based on the detected sensor feature point. However, the present invention is not limited to this, and straight lines, line segments, multi-order curves, circles, ellipses and other curves, planes, curved surfaces and other surfaces, cubes, spheres, and other three-dimensional features that indicate features on the object are detected and detected. The boundary of the continuous surface can be recognized based on the feature.

  In the fourth to sixth embodiments, the camera 222 is arranged so that the xrs-yrs plane in the sensor coordinate system is parallel to the xca-yca plane in the camera coordinate system. First, if an image including a measurement point that can be measured within the scanning range of the distance measuring sensor 212a can be taken, the image can be arranged at an arbitrary position and orientation with respect to the distance measuring sensor 212a.

In the second to sixth embodiments, the encoder 218 is provided on the drive rotating shaft. However, the present invention is not limited to this, and the encoder 218 may be provided on the driven rotating shaft.
Thereby, the scanning angle in the second scanning process can be detected with high accuracy without being affected by the transmission error.
In the second to sixth embodiments, the rotational driving force of the driving rotating shaft is transmitted to the driven rotating shaft via the pulleys 220a and 220b and the belt 221. Not limited to this, the configuration may be such that the rotational driving force of the drive rotary shaft is transmitted to the driven rotary shaft via a plurality of gears.

  In the second to sixth embodiments, the distance information is acquired in the first scanning process discretely (distance information is acquired in the first scanning process after being rotated in the second scanning process). However, the present invention is not limited to this, and the configuration is such that the scanning angle and the measurement distance are associated with each other continuously (distance information is acquired by the first scanning process while being rotated by the second scanning process). You can also.

In the second to sixth embodiments, the scanning angle range and the scanning unit angle are set based on the command signal from the CPU 60. However, the present invention is not limited to this, and the three-dimensional distance measurement is performed. A configuration in which the apparatus 200 is set in advance may be employed.
In the second to sixth embodiments, the three-dimensional distance measuring device 200 rotates the distance measuring sensor 212a around the yrs' axis and rotates the two-dimensional distance measuring device 212 around the zrs axis. However, the present invention is not limited to this, and the distance measuring sensor 212a may be rotated about the zrs axis, and the two-dimensional distance measuring device 212 may be rotated about the yrs' axis. Further, not only about the yrs ′ axis and the zrs axis, but any two axes that are orthogonal to the measurement direction of the distance measuring sensor 212a may be used. Further, not limited to such a rotation mechanism, the distance measuring sensor 212a is moved in a first scanning direction that is different from the measuring direction of the distance measuring sensor 212a, and the measuring direction of the distance measuring sensor 212a is different from the first scanning direction. It can also be configured as a moving mechanism so as to move the distance measuring sensor 212a in two scanning directions. In this case, as the shape of the movement path, a circular arc or other curve can be adopted in addition to a straight line. A combination of a rotating mechanism and a moving mechanism can also be used.

Such a configuration change can be similarly applied to the above-described configuration including the plurality of distance measuring sensors 212a and the rotation mechanism.
In the fourth to sixth embodiments, as shown in FIG. 47A, the two-dimensional distance measuring device 212 itself is rotated. However, the present invention is not limited to this, and an optical distance measuring sensor is used. As shown in FIG. 47B, a mirror inserted on the optical axis in the measurement direction may be rotated.

FIG. 47 is a diagram showing a configuration in the case where the measurement direction of the distance measuring sensor is changed.
Moreover, although the said 2nd thru | or 6th embodiment was demonstrated as an independent embodiment, the said 2nd thru | or 6th embodiment can also be applied with respect to the said 1st Embodiment. .
In the second to sixth embodiments, the leg-wheel type robot, the object recognition device, and the object recognition method according to the present invention are applied to the case of going over the stairs. The same applies to the case of overcoming the step.

  In the second to sixth embodiments, the leg-wheel type robot, the object recognition device, and the object recognition method according to the present invention are applied to the leg-wheel type robot 100. However, the present invention is not limited to this. The present invention can be applied to other cases without departing from the spirit of the invention. For example, the present invention can be applied to a leg-wheel type robot that realizes a leg structure with a linear motion joint, a robot having another configuration, a vehicle, and other devices. Further, by combining with a means for transmitting recognition information, development to a device and a recognition method as a means for a visually impaired person to recognize the outside world is also conceivable.

(A)-(c) is a figure which shows the structure of the leg wheel apparatus 11 which concerns on this invention. 1 is a front view of a leg wheel type robot 100 according to the present invention. 1 is a side view of a leg wheel type robot 100 according to the present invention. It is a figure which shows the structure of the obstruction sensors 34 and 36. FIG. 2 is a block diagram showing a movement control system of a leg wheel type robot 100. FIG. It is a flowchart which shows the conversion process to wheel drive mode. It is a figure which shows an example in case the leg part 12 exists in a retracted position, (b) is a figure which shows an example in case the leg part 12 is not in a retracted position. It is a flowchart which shows a raising / lowering control process. It is a figure for demonstrating the principle of a light cutting method. It is a figure which shows the state which irradiated the laser beam to the level | step difference, and the image of the image pick-up element of the camera. (A)-(e) is a figure which shows an example of the movement operation | movement when getting over the level | step difference of the leg wheel type robot 100. FIG. It is a figure which shows an example of the movement operation | movement when getting over a high level | step difference. 1 is a front view of a leg wheel type robot 100. FIG. 1 is a side view of a leg wheel type robot 100. FIG. It is a front view (yrs-zrs plane) of the three-dimensional distance measuring apparatus 200. It is a side view (xrs-zrs plane) of the three-dimensional distance measuring apparatus 200. It is a top view (yrs-xrs plane) of the three-dimensional distance measuring apparatus 200. It is a figure which shows the scanning range of a ranging sensor. 2 is a block diagram showing a movement control system of a leg wheel type robot 100. FIG. It is a block diagram which shows the control structure of the two-dimensional distance measuring apparatus 212. 3 is a block diagram showing a control structure of a three-dimensional distance measuring apparatus 200. FIG. It is a figure for demonstrating the principle of the distance measurement of the two-dimensional distance measuring apparatus 212. FIG. It is a figure which shows the case where it scans by the 1st scanning process and the 2nd scanning process. It is a figure which shows the example of a distance measurement of the three-dimensional distance measuring apparatus 200. FIG. 4 is a flowchart showing object recognition processing executed by the three-dimensional distance measuring apparatus 200. It is a figure for demonstrating the principle of Hough conversion. It is a flowchart which shows a raising / lowering control process. It is a graph which shows the measurement result by the 1st scanning process. It is a graph which shows the result of having converted the distance information of the rotation coordinate system of each measurement point of FIG. 28 into the coordinate information of a rectangular coordinate system. It is a graph which shows the measurement point in a rectangular coordinate system, and the result of Hough transform. It is a figure which shows the determination result of a continuous surface. 5 is a flowchart showing object recognition processing executed by the three-dimensional distance measuring apparatus 200. It is a graph which shows the measurement point in a rectangular coordinate system, the result of line segment connection, and the result of Hough transform. It is a figure for demonstrating the principle of the object recognition using the camera 222 and the three-dimensional distance measuring apparatus 200. FIG. 4 is a flowchart showing object recognition processing executed by the three-dimensional distance measuring apparatus 200. 2 is a diagram illustrating a sensor coordinate system, a camera coordinate system, and a coordinate system of an image sensor surface of a camera 222. FIG. It is a figure for demonstrating the case where the matching of the segment of a camera image and a sensor feature point, grouping, and the determination of a boundary line are performed. It is a flowchart which shows a raising / lowering control process. It is a figure which shows the processing result of a camera image. It is a figure which shows the determination result of a continuous surface. It is a figure which shows the projection result to the camera image of a sensor feature point. 4 is a flowchart showing object recognition processing executed by the three-dimensional distance measuring apparatus 200. 4 is a flowchart showing object recognition processing executed by the three-dimensional distance measuring apparatus 200. It is a figure which shows the example of calculation of inclination. It is a figure which shows an example of the inclination of the x-axis direction computed by the least square method, and az-axis direction. It is a figure which shows an example of the appearance frequency of the inclination with respect to a certain scanning plane. It is a figure which shows the structure in the case of changing the measurement direction of a ranging sensor.

Explanation of symbols

100 leg wheel type robot 10 base 11 leg wheel device 13 first link 14 first gear box (first rotation joint)
15 Shaft 16 Leg drive mechanism (second rotary joint)
17 Wheel drive mechanisms 16a, 16b, 17a, 17b First to second pulleys 16c, 17c First to second belts 19 Second link 20 Wheels 22, 24 Leg tip sensors 26 Horizontal lasers 28, 30 Vertical lasers 32 Cameras 34 36 Obstacle sensor 40 Joint motor 50 Wheel motor 42, 52 Encoder 44, 54 Driver 60 CPU
62 Angle capture I / F
64 Communication I / F
70 Three-axis attitude sensor 76 Hub 200 Three-dimensional distance measurement device 204 Lower support plate 206 Upper support plate 208 Camera support plate 210 Sensing processor 212 Two-dimensional distance measurement device 212a Distance sensor 212c, 216 Motor 212d, 218 Encoder 212b, 214 Driver 220a, 220b Pulley 221 Belt 32, 222 Camera

Claims (11)

A base, a plurality of legs supported to the base via joints, wheels provided rotatably on the legs, and an actuator for applying power to drive the legs and the wheels; A leg wheel type robot that includes a control means for controlling the actuator and moves by driving at least one of the leg portion and the wheel according to the environment,
The wheel is provided in a hip joint portion configured on an end side supported by the base body of the leg portion, and an actuator for driving the wheel is provided in the vicinity of the wheel,
The said control means performs the control which reduces the drive electric energy supplied with respect to the actuator which is not used for the said movement among the actuators which drive the said leg part and the said wheel, The leg wheel type robot characterized by the above-mentioned.   The leg-wheel type robot according to claim 1, wherein the actuator includes a first actuator that drives the leg and a second actuator that drives the wheel independently.   The control means controls the first actuator so as to move and hold the plurality of legs at a position above the ground contact surface of the wheel when moving using only the wheel. The leg-wheel type robot according to claim 2.   The control means performs control to cut off the supply of driving power to the first actuator while the plurality of legs are moved only by the wheel after being moved to a position above the ground contact surface of the wheel. The leg-wheel type robot according to claim 3, wherein the leg-wheel type robot is performed.   The control means is positioned above the first actuator while the plurality of legs are moved only by the wheel after being moved to a position above the ground contact surface of the wheel. 4. The leg-wheel type robot according to claim 3, wherein control is performed so as to supply a minimum amount of driving power necessary for maintaining the posture of the leg.   6. The control device according to claim 2, wherein the control unit performs control to cut off the supply of driving power to the second actuator while the movement using only the leg portion is performed. The leg-wheel type robot described in the item.   The control means controls the first actuator such that when the leg is driven to get over an obstacle, the wheel provided on the leg that gets over the obstacle comes into contact with the obstacle. The leg-wheel type robot according to any one of claims 2 to 6, wherein the leg-wheel type robot is provided. A leg portion supported via a joint with respect to a base of a leg-wheel type robot, a wheel rotatably provided on the leg portion, and an actuator for applying power for driving the leg portion and the wheel A leg wheel device for moving the leg wheel type robot by driving at least one of the leg portion and the wheel,
The wheel is configured to be provided in a hip joint portion configured on an end side supported by the base body of the leg portion, and an actuator for driving the wheel is configured to be provided in the vicinity of the wheel. Leg wheel device.   The leg wheel device according to claim 8, wherein an actuator that rotationally drives the wheel is provided independently of an actuator that drives the leg portion.   A leg-wheel type robot comprising the leg-wheel device according to claim 8 or 9.   The leg according to any one of claims 1 to 7, further comprising leg posture changing means for changing the posture of the leg in accordance with an environment during travel using only the wheels. Wheeled robot.

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