JP2008142841A - Mobile robot - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mobile robot in which excessive restriction is not set for the moving speed of the mobile robot body. <P>SOLUTION: This mobile robot comprises the mobile robot body and an attitude changing member relatively deformable in attitude relative to the mobile robot body. When an obstacle is detected, a first speed vector determining the moving speed and the moving direction of the mobile robot body and a second speed vector determining the moving speed and the moving direction of the end part of the attitude changing member relative to the mobile robot body are calculated according to the direction and speed of the mobile robot body and the information on the position of the end part of the attitude changing member. A control part obtains the speed component in the direction in which the mobile robot body moves toward the obstacle, and so controls a moving means and a drive means that the time required for the moving speed of the end part of the attitude changing member relative to the obstacle becomes zero is larger than the time in which the mobile robot body reaches the obstacle when it continues to move at the speed when the first speed vector is calculated. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a mobile robot that moves in an area where an object that becomes an obstacle exists in a moving space, for example, an AGV used in a factory or the like, and an autonomous mobile robot that autonomously moves indoors and outdoors. is there.

  A mobile robot that moves inside a building such as a factory moves along a predetermined movement route or an autonomously determined movement route. Such a mobile robot moves at a predetermined speed on a predetermined movement path. When an obstacle exists on the movement path, the movement speed toward the obstacle is reduced when the obstacle is detected. It is necessary to stop before touching with sufficient distance to the obstacle.

However, when such a mobile robot is provided with a posture deforming member such as an arm portion that is deformed by driving with respect to the mobile robot main body as described in Patent Document 1, for example, the mobile robot main body Even if the moving speed is reduced, the posture deforming member may come in contact with an obstacle depending on the posture. Therefore, when the mobile robot detects an obstacle, the degree to which the mobile robot body can be decelerated must be made sufficiently large. Speed must be limited. Therefore, it may be necessary to set an excessive speed limit on the moving speed of the mobile robot body, which may be an obstacle to rapid movement of the robot.
JP 2001-173026 A

  The present invention has been made to solve such a problem, and an object of the present invention is to provide a mobile robot that does not place an excessive limit on the moving speed of the mobile robot body.

  A mobile robot according to the present invention has a mobile robot main body having a moving means that moves along a predetermined movement path, and is attached to the mobile robot main body, and is controlled to be capable of posture deformation relative to the mobile robot main body. An obstacle detecting unit that detects an obstacle and obtains position information of the obstacle, and a driving unit that drives the attitude deforming member and deforms the attitude. A control unit that controls the drive unit and the moving unit, a tip position calculation unit that calculates position information of the tip part of the posture deforming member, a detection unit that detects a moving direction and a speed of the mobile robot body, And the direction and speed of the mobile robot body detected by the detector when the obstacle is detected by the obstacle detector and the position information is acquired. Based on the position information of the tip portion of the posture deforming member calculated by the tip position calculation unit, a first speed vector that determines the moving speed and moving direction of the mobile robot body, and the relative position of the tip portion to the mobile robot body. A second speed vector that determines a moving speed and a moving direction is calculated, and the mobile robot body is an obstacle of a combined speed vector obtained by the control unit combining the first speed vector and the second speed vector. The tip of the posture-deforming member is calculated with respect to the speed component in the direction toward the front and the time required to reach the obstacle when the mobile robot body continues to move at the speed when the first speed vector is calculated. The control unit controls the moving means and the drive unit so as to increase the time required until the relative movement speed of the unit with respect to the obstacle becomes zero. It is an butterfly.

  When the mobile robot as described above finds an obstacle in the movement path, the moving speed of the mobile robot body and the obstacle between the posture deforming member and the obstacle are determined from the distance between the tip position of the posture deforming member and the obstacle. The moving means and the drive unit are controlled so that the tip of the posture deforming member does not come into contact with the obstacle in consideration of the speed of the deformable movement with respect to. At that time, the posture deforming member is prevented from coming into contact with the obstacle more reliably while taking into account the degree of deceleration of the moving speed of the tip of the posture deforming member and the degree of decelerating the moving speed of the mobile robot body. In addition, the control unit controls the moving means and the driving unit. Therefore, when an obstacle is found in the movement route, the degree of limiting the moving speed of the mobile robot body is maximized by maximizing the movement that the tip of the posture deforming member avoids the obstacle. As a result, it is possible to eliminate the necessity of excessively limiting the moving speed of the mobile robot body more than necessary.

  In the present invention, the moving path along which the mobile robot according to the present invention moves may be a predetermined moving path, or may be determined autonomously by the mobile robot. In the former case, when the mobile robot detects an obstacle, the mobile robot stops on the movement path and stops its movement until the obstacle is removed. In the latter case, the mobile robot stops the obstacle after detecting the obstacle. It is possible to continue the movement by correcting the movement route so as to avoid it.

  Further, the control unit reduces a maximum deceleration that decelerates the movement of the tip of the posture deforming member in a direction parallel to the combined velocity vector, and a first component that decelerates a velocity component in a direction toward the obstacle of the mobile robot body. The control unit controls the moving unit and the drive unit by dividing into a deceleration and a second deceleration that decelerates the speed component in the direction toward the obstacle at the tip of the posture deforming member. It is preferable that In this case, when the relative distance between the position of the tip and the position of the detected obstacle is equal to or less than a certain distance, the control unit increases the first deceleration to be greater than the second deceleration. Thus, the moving means and the drive unit may be controlled. In this way, when the distance between the mobile robot and the obstacle is long, the speed limit of the mobile robot body is relaxed by placing importance on contact avoidance due to the attitude deformation speed of the attitude deforming member. When the distance is short, it is possible to control so as to reliably avoid contact with an obstacle by limiting the speed of the mobile robot body. Therefore, in such a mobile robot, it is possible to avoid contact with an obstacle without reducing the speed of the mobile robot body as much as possible.

  In such a mobile robot, it is preferable that an acceleration sensor for detecting a change in acceleration caused by an external force is provided. By providing such an acceleration sensor, it is possible to quickly and accurately detect that the mobile robot has come into contact with the obstacle even when the obstacle cannot be detected. Such an acceleration sensor may be provided on the posture deforming member or on the mobile robot body. In particular, when the acceleration sensor is provided on the posture deforming member, even if the obstacle detecting unit cannot detect the obstacle due to the posture that the posture deforming member can take, the obstacle and the posture deforming member It is preferable because it is possible to quickly detect that the contact has been made.

  In addition, it is preferable that such a mobile robot further includes a camera that visually acquires surrounding environmental information. With the camera provided in this way, it is also possible to acquire an image when an obstacle and a mobile robot come into contact or are about to come in contact, and determine the cause of contact or the cause of contact . It should be noted that the information grasped by such a camera is preferably obtained as digitized image information when performing signal transmission and storage.

  The posture deforming member may be an arm part having one end attached to the mobile robot body, and at least one joint part is provided between one end of the arm part and the tip of the arm part. It may be included. Such a mobile robot deforms its posture so that it does not come into contact with the detected obstacle and moves it at a moving speed when moving using an arm that deforms the posture by driving a joint. It becomes possible to adjust.

  In addition, such a mobile robot is not particularly limited in the moving area, but may be one that moves in a plane. In this case, the mobile robot stores a movement map specified in the moving plane, and moves autonomously on the movement map. On the stored movement map, the obstacle detection unit A movement path creation unit that creates a movement path based on the detected position information of the obstacle may be further provided, and the moving unit may move the mobile robot body based on the created movement path. In the present invention, the plane on which the mobile robot moves is not limited to a flat floor surface or the like, and may be provided with a slight step or uneven portion.

  In the case of such a mobile robot, it is possible to avoid a contact with an obstacle as much as possible by creating a movement route from position information of the obstacle grasped in advance and moving along the created movement route. In such a mobile robot, the created movement route may be corrected according to the environment around the mobile robot. In this way, even if there are obstacles around the mobile robot, it is not possible to avoid contact with obstacles by adjusting the moving speed. Its movement can be controlled to avoid contact with objects.

  Note that the movement map may be a grid map created by virtually depicting grid lines connecting lattice points arranged at substantially constant intervals in the plane. When such a grid map is used as a movement map, the position of the mobile robot can be grasped accurately and easily, and a movement route on the movement map can be easily created.

  Moreover, it is preferable that the said mobile robot main body is equipped with the absolute position acquisition part which acquires the self absolute position on a movement map. As such an absolute position acquisition unit, an absolute position of the mobile robot body may be acquired by receiving absolute position information transmitted from equipment such as GPS provided outside the mobile robot. . The mobile robot body may correct the environment information acquired by the environment information acquisition unit based on the absolute position information obtained by such an absolute position acquisition unit.

  The mobile robot body may include a self-position calculating unit that calculates a self-position from the direction and distance moved on the movement map. Such a self-position calculation unit may estimate the self-position using the environmental information obtained by the environment information acquisition unit, or may be provided separately from the environment information acquisition unit. Good. As an example of such a self-position calculation unit, when the mobile robot body is provided with moving means by driving wheels, the number of rotations and the direction of rotation of the wheels obtained when moving from the moving origin to another point, Examples include calculating the position of the moved point based on the direction of the wheel.

  As described above, according to the present invention, it is possible to provide a mobile robot that does not place an excessive limit on the moving speed.

Embodiment 1 of the Invention
The mobile robot according to the first embodiment of the present invention will be described below with reference to FIGS. 1 to 6. In this embodiment, it is assumed that the mobile robot is a vehicle-type mobile robot that autonomously moves on a plane by driving a pair of wheels.

  FIG. 1 shows a vehicle type represented by an AGV or the like that moves along a predetermined movement path in a limited area P (area surrounded by a solid line) on the floor 1 as a moving plane. 1 schematically shows an embodiment of a mobile robot 10. In this embodiment, the floor portion 1 is a plane on which a plurality of facilities (41, 42, 43, 44) are installed indoors, such as in a factory. It is assumed that the movement route 30 is predetermined so as to avoid equipment.

  FIG. 2 is a schematic view schematically showing the configuration of the mobile robot 10 shown in FIG. 1 as viewed from the side. As shown in FIG. 2, the mobile robot 10 includes a box-type mobile robot body 10a and a posture. It is comprised from the arm part 100 as a deformation | transformation member. One end of the arm unit 100 is connected to the upper surface of the mobile robot body 10a, and the posture of the arm unit 100 can be changed relative to the mobile robot body 10a. Hereinafter, the mobile robot body 10a and the arm unit 100 will be described in detail.

  3 is a diagram schematically showing the configuration of the mobile robot body 10a shown in FIG. 2. As shown in FIG. 3, the mobile robot body 10a includes a pair of opposed wheels 11 and a caster 12. This is a two-wheeled vehicle. The mobile robot body 10a is movable with these wheels 11 and casters 12 in a state where the mobile robot body 10a is supported in its horizontal position. Further, in the mobile robot body 10a, a motor 13 for driving the wheels 11, a counter 14 for detecting the number of rotations of the wheels, and a control signal for driving the wheels are created. A control unit 15 including an arithmetic processing unit that transmits a control signal and a battery (not shown) for supplying power to these components are provided. In a storage area 15a such as a memory as a storage section provided in the arithmetic processing section of the control section 15, a movement path in the area P is stored, and the movement of the mobile robot 10 is performed based on the control signal. A program for controlling the speed and the like is stored. That is, the moving means referred to in the present invention is configured by a set of components for moving the mobile robot body 10a such as the wheels 11, the casters 12, and the motor 13.

  Further, a sensor 16 as an obstacle detection unit for detecting an obstacle appearing in the moving direction is attached to the front surface of the mobile robot body 10a, and the sensor 16 moves forward in the forward direction of the mobile robot body 10a. An existing obstacle can be detected. The sensor 16 is, for example, a laser sensor that three-dimensionally irradiates an infrared laser, acquires the shape of an obstacle detected from the reflected state of the laser, and the distance from the front surface of the mobile body 10a, and applies to the mobile robot body 10a. It is possible to grasp the relative position of the obstacle. As will be described later, when detecting an obstacle with the sensor 16, the control unit 15 controls the motor 13 and the like based on the shape of the obstacle and the distance from the mobile robot body, and the mobile robot body 10a and an arm described later Control the operation of the unit.

  On the front surface of the mobile robot body 10a, a camera 17 is provided for imaging an object such as an obstacle that exists in the moving direction of the mobile robot body 10a. Information is input to the control unit 15. In the control unit 15, the digitized information is recorded in the storage area 15a and can be output to the outside via an output unit or the like (not shown). Thus, by recording surrounding information with the camera 17, for example, a situation such as when the mobile robot body 10 a is in contact with an obstacle can be visually confirmed later.

  The mobile robot body 10a configured in this manner independently controls the drive amount of the pair of wheels 11, thereby moving straight, moving in a curve (turning), moving backward, and rotating on the spot (centering on the middle point of both wheels). ) And other moving operations can be performed. Then, the mobile robot body 10a moves so as to follow the movement path in the area P stored in the storage area 15a.

  Next, the arm unit 100 connected to the mobile robot body 10a will be described with reference to FIG. As shown in FIG. 2, the arm unit 100 is provided on the upper surface of the mobile robot body 10 a, and a base unit 101 that can rotate with respect to the axis H, and in the directions of arrows R <b> 1 and R <b> 2 with respect to the base unit 101. The arm unit main body 102 having one end connected to be rotatable is provided, and a hand unit 103 provided at the other end of the arm unit main body 102.

  The arm body 102 has a first link member 102a whose one end is rotatably connected to the base 101, a joint member 102b provided at the other end of the first link member 102a, and one end connected to the joint member 102b. Second link member 102c. The first link member 102a and the second link member 102c are configured to be rotatable via a joint member 102b. Further, the other end of the second link member 102c is rotatable with respect to the axis S. A hand portion 103 is attached to the head.

  The hand portion 103 includes a substrate 103a that is provided so as to be rotatable with respect to the second link member 102c, and plate members 103b and 103c that are slidably attached to the substrate 103 so as to be close to and away from each other. It is configured. A gripping operation for gripping an object can be performed by sliding the plate-like members 103b and 103c in the approaching direction.

  The one end of the first link member 102a connected to the base portion 101 and the joint member 102b provided between the first link member 102a and the second link member 102c may be a single drive unit. The joint angle is driven by a plurality of motors (not shown) so as to change within a predetermined range. As a result, the arm main body 102 can change its posture relative to the mobile robot main body 10a.

  In this embodiment, the arm unit 100 as the posture deforming member configured as described above has an end portion opposite to one end attached to the mobile robot body 10a as a tip position, and the tip position 100a is a hand. The center point (C) of the portion 103 is determined. That is, when the plate-like members 103 b and 103 c of the hand portion 103 are in the most separated state, the point located in the middle of these plate-like members is defined as the tip of the arm portion 100. The present invention is not limited to this. For example, when the volume occupied by the arm unit 100 of the hand unit 103 is relatively large, the tip of the hand unit, that is, the end opposite to the end unit attached to the arm unit main body. The center of the end portion may be the tip position of the arm portion.

  The posture change of the arm unit main body 102 is controlled by the control unit 15 provided in the mobile robot 10a, and the position of the distal end position 100a of the arm unit relative to the mobile robot main body 10a is determined by the joint angle, the known length of each link member, and the like. The relative position can be grasped. That is, in the present embodiment, the control unit 15 acts as a tip position calculation unit that calculates the tip position of the arm unit. Further, also in the hand unit 103, the rotation operation of the substrate 103 a and the sliding operation of the plate-like members 103 b and 103 c are realized by a motor (not shown), and these operations are controlled by the control unit 15.

  The procedure for controlling the operation of the mobile robot 10 configured as described above when moving along the movement path 30 will be described with reference to the schematic diagrams shown in FIGS. 4 and 5 and the flowchart shown in FIG. To do. In the present embodiment, as shown in FIG. 4, when the mobile robot 10 moves along the route from the movement start point to the movement end point on the movement route 30, an obstacle such as a human being at the point 30 a of the movement route 30. An example is shown in which 200 is present, and the sensor 16 provided in the mobile robot body 10a detects the obstacle 200 by a distance L in front and controls the operation of the mobile robot 10. The above-mentioned distance L is set sufficiently larger than the distance from the front surface of the mobile robot body to the position where the tip position 100a of the arm unit 100 can reach.

FIG. 5 shows a state of the arm unit 100 when the mobile robot 10 detects the obstacle 200 in front of the obstacle 200. The distance between the front surface of the mobile robot body 10a of the mobile robot 10 and the obstacle 200 is L. At this time, the arm section body 102 of the arm section 100 of the mobile robot 10 rotates about the axis H, and the obstacle It is assumed that the object 200 is tilted by an angle θ with respect to the moving direction when the object 200 is detected, and the object 200 is moving at a speed v in a direction to decrease the angle. At this time, the moving speed of the mobile main body 10a is V ₀ , and the control unit 15 provided in the mobile robot main body 10a is connected to the center point C of the hand unit 103 provided in the arm unit 100 and the obstacle 200. Assume that the relative positional relationship is grasped three-dimensionally. The operation control after the mobile robot 10 detects the obstacle 200 in such a state will be described with reference to the flowchart shown in FIG.

  When the mobile robot 10 that has started to move from the movement start point on the movement path 30 detects the obstacle 200 by the sensor provided in the mobile robot body 10a at the point 30a (STEP 101), the control unit 15 sets the obstacle 200 to 3 A three-dimensional shape is obtained, and the relative position of the obstacle 200 (such as the distance L from the mobile robot body 10a to the obstacle 200) with respect to a predetermined position of the mobile robot body 10a is grasped (STEP 102).

Then, the control unit 15 obtains the moving speed moving of the mobile robot body 10a at this time, determining a first velocity vector _{V 0} to determine the moving direction and the moving speed of the mobile robot body 10a (STEP 103). Further, the position information of the distal end (center point C) of the arm unit 100 is acquired, and a second speed vector v that determines the moving direction and moving speed of the distal end position 100a of the arm unit is obtained (STEP 104). the synthesis to obtain the synthesis velocity vector _{V 1} (STEP105).

Then, the distance D from the arm tip 100a to the obstacle 200 (200a) in the direction indicated by the synthesized velocity vector obtained by synthesis is obtained (STEP 106). Further, the maximum deceleration α ₀ in the direction of the combined velocity vector of the arm unit 100 is obtained from the operating conditions of the arm unit 100 and the mobile robot body 10a, and the distance D and the size of the combined velocity vector obtained as described above are obtained. the relationship between the (velocity) _{V 1,} is controlled so as to satisfy the following relation shown in equation 1 (STEP 107). Specifically, the control unit 15 distributes the magnitude of the combined speed vector to control for reducing the speed of the mobile robot body 10a driven by the motor 13 and control for adjusting the moving speed by the arm drive 100. By doing so, it adjusts so that this Formula 1 may be satisfy | filled.

・・・式１

... Formula 1

Note that the above equation 1 means that the time T ₀ (= D / V ₁ ) for reaching the obstacle when the mobile robot 10 continues to move at the speed V1 and the arm portion of the mobile robot 10 The time T ₁ (= V ₁ / α ₀ ) required until the relative movement speed with respect to the obstacle becomes zero is provided so as to satisfy the relationship of T ₀ > T ₁ . In the above equation 1, k is a coefficient of 1 or more (for example, k = 2), and it can be controlled to stop at a position as far as possible from the obstacle by increasing the value of k.

When the mobile robot is controlled based on such a relationship, the distribution ratio between the degree of limiting the speed of the mobile robot body 10a and the limit of the speed of the arm unit 100 toward the obstacle is appropriately determined according to the situation. It is done. For example, when the distance D between the tip of the arm unit 100 and the obstacle is a predetermined distance D ₀ or more, the arm unit 100 can be moved to avoid contact between the tip of the arm unit and the obstacle. The speed limit of 100 is increased and the speed limit of the mobile robot body 10a is suppressed as much as possible. Specifically, the moving speed of the arm unit 100 is minimized by limiting the speed of the arm unit 100 to maximize the degree of deceleration at which the arm unit 100 can be decelerated.

Conversely, if the distance between the tip and the obstruction of the arm portion 100 is less than the D _0, the motion of the arm portion 100 determines that the hard avoid contact with the obstacle, the speed limit of the mobile robot 10a The speed is set to be larger than the speed limit at which the arm unit 100 moves. Specifically, the mobile robot body 10a is gradually decelerated as the distance between the tip of the arm unit 100 and the obstacle approaches, with the degree of deceleration at which the mobile robot body 10a can be decelerated being maximized. In place of the deceleration control of the mobile robot body 10a, the moving speed of the mobile robot body 10a can be reduced to the maximum possible speed described above when the distance between the tip of the arm and the obstacle is below a certain distance. You may make it reduce by the deceleration degree.

  Thus, by controlling the speed limit of the arm unit 100 and the speed limit of the mobile robot body 10a according to the situation, the speed of the mobile robot body is reduced only when the possibility of contact with an obstacle is high. Therefore, the kinetic energy of the mobile robot is not lost more than necessary.

  Furthermore, when the adjustment of the speeds of the mobile robot body 10a and the arm unit 100 is started in this way, the mobile robot 10 takes a direction toward the obstacle 200 with the camera 17, and controls the image data obtained by the imaging. The data is temporarily stored in the storage area 15a in the unit 15 (STEP 108). Then, until the mobile robot 10 stops in front of the obstacle 200, the camera 17 continues to capture images and stores image data.

  As described above, the control unit 15 of the mobile robot 10 controls the movement of the mobile robot body 10a and the arm unit 100 so as to stop before the obstacle 200 by adjusting the speed of the mobile robot 10, so that the mobile robot Stop before the object 200 (STEP 109). At this time, the mobile robot 10 grasps the current position on the travel route 30 that has stopped.

  Then, the sensor 16 detects whether or not the obstacle 200 has been removed from the movement path 30 (STEP 110). When it is detected that the obstacle 200 has been removed, the movement is again made along the movement path 30. Start (STEP 111). Then, when the mobile robot 10 reaches the movement end point on the movement route 30, it stops its movement (STEP 112).

  According to the mobile robot in the present embodiment, when the mobile robot body detects an obstacle, the moving motion can be controlled in consideration of the tip position of the arm unit. Therefore, it is possible to control the movement of the mobile robot without excessively limiting the moving speed of the mobile robot body. Furthermore, by distributing the degree of deceleration between the mobile robot body and the arm according to the distance between the mobile robot body and the obstacle, the tip position of the arm unit can be determined without reducing the moving speed of the mobile robot body more than necessary. It can be made not to touch an obstacle.

  In the above-described embodiment, an image is captured from the mobile robot body toward the obstacle by the camera and the image data is stored. Such imaging is performed immediately before the mobile robot contacts the obstacle. It may be controlled to perform only. In that case, the positional relationship between the mobile robot and the obstacle may be acquired by the aforementioned sensor or other means.

Embodiment 2 of the Invention
Next, a second embodiment of the present invention will be described with reference to FIGS. Note that the mobile robot in this embodiment has the same main configuration as that shown in the first embodiment, and therefore, the same or similar components are denoted by the same reference numerals, and the description thereof is omitted. It shall be.

  As shown in FIG. 7, the mobile robot 10 ′ in the present embodiment autonomously moves within a limited movement map Q (area surrounded by a broken line) on the floor 1 as a moving plane. It is. In this embodiment, no object is particularly placed in the movement map Q on the plane 1, and after the mobile robot 10 'determines a movement path in the movement map Q, it moves according to the movement path. At the same time, it is assumed that the moving route can be modified according to the surrounding environment to change the moving direction. Although details are omitted, the mobile robot 10 ′ in the present embodiment also includes the mobile robot body 10 a and the arm unit 100 as in the above-described embodiment, and the mobile robot body 10 a has a pair of opposed wheels 11. And an opposite two-wheeled moving body including casters 12.

  And the control part 15 with which the mobile robot main body 10a was equipped is a memory area 15a as a memory | storage part with which it was equipped in the inside, and the moving speed, the moving direction, and movement of mobile robot 10 'based on a control signal. A movement map Q is stored together with a program for controlling the distance and the like.

  In addition, although not shown, the mobile robot body 10a includes a position acquisition unit for acquiring its own position. This position acquisition unit includes an absolute position acquisition unit that acquires its own absolute position on the movement map Q, and a self-position calculation unit that calculates its own position from the direction and distance moved on the movement map Q. Yes.

  The absolute position acquisition unit analyzes an antenna (not shown) provided at a predetermined location such as the upper surface of the mobile robot body 10a for acquiring information indicating its own absolute position and information indicating the acquired absolute position. And a control unit 15 for calculating its absolute position. Such information indicating the absolute position is transmitted to the mobile robot 10 ′ from an absolute position detecting means (not shown) using a position estimation method such as a Kalman filter or a particle filter. In the present embodiment, such absolute position detecting means is provided outside the mobile robot body 10a, but may be provided integrally with the mobile robot 10 ′.

  The self-position calculating unit includes the counter 14 and the control unit 15 described above. That is, the number of rotations of the wheels 11 detected by the counter 14 is accumulated in the control unit 15 to obtain information such as the moving speed and distance of the mobile robot body 10a, and the mobile robot in the movement map is obtained from these information. The self position (odometry position) of the main body 10a is calculated.

  The position information obtained from these self-position calculation units is periodically corrected by the position information obtained by the absolute position detection unit, so that the mobile robot body 10a can always recognize the accurate self-position.

  The mobile robot 10 ′ configured in this way independently controls the drive amount of the pair of wheels 11, thereby moving straight, curving (turning), moving backward, and rotating on the spot (centering on the middle point of both wheels). ) And other moving operations can be performed. Then, the mobile robot 10 ′ autonomously creates a movement route to the designated destination in the movement map Q in accordance with a command from an external server or the like (not shown) that designates the movement location. Then, the vehicle reaches the destination by moving so as to follow the movement route.

  Next, a grid map created based on the shape of the movement map Q stored in the mobile robot body 10a will be described with reference to FIGS.

  In the storage area 15a provided in the control unit 15, a grid line connecting the lattice points arranged at substantially constant intervals d (for example, 10 cm) is virtually depicted in the shape of the entire movement map Q on the floor portion 1. The grid map obtained by doing is stored.

  FIG. 8 illustrates an example of the grid map described above. The grid map 20 is a depiction of grid lines 22 connecting lattice points arranged at substantially constant intervals d inside the outer frame 21 simulating the shape of the movement map Q. Then, using the grid unit 23 surrounded by the grid line 22, the location corresponding to the mobile robot body 10a's own position, the movement end point that is the destination, and the movement direction of the mobile robot body 10a at the movement end point Is identified. Note that the interval d can be changed as appropriate according to conditions such as the curvature of the mobile robot body 10a that can be moved and the accuracy of recognizing the absolute position, and can also be used as a threshold value when it is determined that a slip has occurred. is there.

In addition, the control unit 15 creates a movement route from the movement start point to the movement end point that is the destination, using the self-position specified on the grid map 20 as a movement start point, and also acts as a movement route creation unit. To do. The mobile robot body 10a moves along the created movement path while obtaining its own position in real time as described above. Specifically, as shown in FIG. 9, the moving body 10a constituting the mobile robot 10 recognizes the moving start point Q _0, the movement route from the movement start point to the moving end point Q _n of interest, predetermined distance At intermediate points Q ₁ , Q ₂ ,. . . Is defined on the grid map 20, and a moving path is created on the grid map 20 by connecting these intermediate points.

  Furthermore, in the mobile robot 10 ′ according to the present embodiment, when an obstacle is detected by the sensor 16 when moving from the movement start point to the movement end point (target point) along the created movement path, the mobile robot body 10a While controlling the motor 13 which drives the wheel 12 so that a motion may be stopped, the motion of the arm part 100 is controlled. Then, the position on the stopped movement route is acquired, and the movement route is corrected from the stopped position so as to reach the movement end point while avoiding the obstacle. Then, the movement after the obstacle is detected moves along the corrected movement route and reaches the movement end point. As described above, the details of the procedure in which the mobile robot 10 ′ detects its presence in front of the obstacle (a point separated by the distance L) and stops the movement are shown in the flowchart shown in FIG. 10 and FIGS. This will be described with reference to a schematic diagram. In the present embodiment, the schematic diagram when the mobile robot detects an obstacle is the same as that shown in FIG.

First, the mobile robot 10 ′ stores a movement map on the floor 1 in a storage area 15 a provided in the control unit 15, and the mobile robot's own position Q ₀ on the movement map and the purpose of movement. to identify the destination point _{Q n} (STEP201). At this time, the mobile robot specifies its own position based on information obtained from either or both of the absolute position acquisition unit and the self-position calculation unit described above. Then, a movement path 30 is created from the identified self-position as a movement start point and a movement end point as a destination point, and movement is started along the movement path 30 (STEP 202). It is assumed that the mobile robot 10 ′ acquires its position information on the movement map at a predetermined timing (for example, every 10 [msec]).

Then, the mobile robot 10 ', as shown in FIG. 11, the sensor 16 recognizes the existence of the obstacle 200 at a point _{Q k} of the front of the movement path 30 by a distance L from an obstacle 200 (STEP 203), Image information about the direction toward the obstacle 200 is acquired using the camera 17 included in the mobile robot body 10a (STEP 204).

After the mobile robot 10 'detects the obstacle 200, the control unit 15 adjusts the speed of the mobile robot 10' so that the mobile robot body 10a stops before the obstacle 200 by adjusting the speed of the mobile robot 10 '. And the movement of the arm unit 100 are controlled. As a result, the mobile robot 10 ′ stops before the obstacle 200 (STEP 205). Note that the camera 17 continues to capture images and stores image data until the mobile robot 10 ′ stops before the obstacle 200. At this time, the mobile robot 10 ′ grasps the position (point Q _k ) on the currently stopped moving route 30, and as shown in FIG. 12, the position of the obstacle 200 and the position of the mobile robot 10 on the movement map. Record (point Q _k ).

Then, the mobile robot 10 'depending on the environment information acquired from the camera 17, as shown in FIG. 13, prohibited area that prohibits the passage of the mobile robot around obstacles such as 200 at the point Q _k of the moving path 30 201 is provided, and a new movement path 31 that avoids the prohibited area 201 is created (STEP 206). New path 31, assuming that the avoidance of obstacles, may be created to be taken the shortest route to the destination point, based on the attitude of the mobile robot 10 'at the point Q _k (moving direction) It may be created by obtaining a movable curvature or the like.

Then, the moving path 30 to reach the point _{Q k,} by replacing the path 31 that created the point _{Q k} and later route, corrects the movement path (STEP 207). Then, the vehicle travels to the destination point Q _n along the travel route thus corrected (STEP 208). In this way, the mobile robot 10 ′ can correct the movement route created at the beginning of movement based on the detected position of the obstacle and reach the destination based on the corrected movement route.

  Then, after reaching the destination point, the mobile robot 10 ′ determines whether or not to continue the movement (STEP 209). If the movement is continued, the mobile robot 10 ′ returns to STEP 201 and moves again by specifying its own position and a new destination point. Continue. When not moving, the mobile robot 10 ′ stops the movement and performs a predetermined end process (STEP 210).

  As described above, in the present embodiment, the movement map for the area to be moved to the storage area provided in the control unit 15 is stored, and when moving along the movement path on the movement map. The obstacle is detected and the movement is stopped in front of the obstacle. Furthermore, it is possible to correct the movement route based on the self-position after the stop and move to the destination along the corrected movement route. Since the corrected movement path is created so as to avoid the detected obstacle, the movement path can be autonomously moved without touching the obstacle.

  The embodiment of the mobile robot and mobile robot control method according to the present invention described above is merely an example, and the present invention is not limited to this.

  For example, in the above-described embodiment, there is an obstacle stopped on the moving path, and the movement of the mobile robot is controlled so as not to contact the obstacle. For example, the mobile robot moves. If there are moving obstacles on the movement path, the movement of the obstacles is predicted, and the movement of the mobile robot body and the posture deforming member tip (arm part) is avoided so as to avoid contact with the obstacles. You may make it control.

  Further, in the above-described embodiment, the posture deforming member that deforms the posture relative to the mobile robot body is exemplified by the joint-driven arm portion, but the present invention is not limited to this. . For example, an antenna attached to the mobile robot body so as to be drivable may be used.

  Furthermore, in the above-described embodiment, a mobile body that drives wheels has been exemplified as the mobile robot. However, for example, a plane such as a legged mobile robot such as a biped walking type that performs a movement operation according to the created gait data is used. Any form may be used as long as it moves on top. Examples of such a mobile robot include a moving body that moves on a plane by driving with a wheel, legged movement, and other methods. In the present invention, even if the plane on which the mobile robot moves includes a slight level difference or uneven portion, in the case of a bipedal legged mobile robot, etc. Since the position of such a step or the like can be predicted, gait data that moves in the area in which these exist can be quickly created.

  In addition, as a movement map stored by the mobile robot, a grid map has been described as an example, but the present invention is not limited to this. For example, a topology map that represents an object on the map as a feature point (node) is used. It can also be used. When such a map is used, it is preferable to create a movement route by a link connecting each feature point (node).

It is the schematic which shows a mode that the mobile robot which concerns on 1st Embodiment moves along the predetermined movement path | route within the area | region defined on the plane to move. It is the schematic which shows notionally the mobile robot main body and attitude | position deformation member (arm part) which comprise the mobile robot shown in FIG. FIG. 3 is a schematic diagram simply showing the internal configuration of the mobile robot body shown in FIGS. 1 and 2. FIG. 2 is a schematic diagram showing how the mobile robot body shown in FIG. 1 detects an obstacle during movement. It is the schematic which shows a mode that the mobile robot main body which detected the obstruction controls the movement of a mobile robot main body and a posture deformation member (arm part). When a mobile robot moves based on the created movement route, it is a flowchart showing a procedure for detecting an obstacle, stopping the movement, and resuming the movement. It is the schematic which shows a mode that the mobile robot which concerns on 2nd Embodiment moves along the movement path | route determined autonomously within the area | region defined on the plane to move. It is a figure showing an example of the grid map memorize | stored inside the mobile robot main body. It is a figure which shows a mode that the movement route for a mobile robot to move on the grid map shown in FIG. 8 is created. It is a flowchart which shows the procedure which detects an obstruction, stops the movement, and also restarts a movement, when moving based on the movement path | route which the mobile robot which concerns on 2nd Embodiment created. It is the figure which showed roughly a mode that an obstacle was detected when a mobile robot moves along a movement path | route. It is the schematic which shows a mode that the position of the detected obstacle and the self position of a mobile robot are recorded on the grid map memorize | stored in the mobile robot main body. It is the schematic which shows a mode that the movement path | route is corrected in the mobile robot which concerns on 2nd Embodiment.

Explanation of symbols

1 ... Floor (plane)
DESCRIPTION OF SYMBOLS 10, 10 '... Mobile robot 10a ... Mobile robot main body 11 ... Wheel 13 ... Drive part 15 ... Control part 15a ... Storage area 16 ... Sensor (obstacle detection part)
17 ... Camera 20 ... Grid map 100 ... Arm (posture deformation member)
100a ... tip position 200 ... obstacle

Claims (11)

A mobile robot main body having a moving means that moves along a predetermined movement path, and a posture deformation member that is attached to the mobile robot main body and is controlled to be capable of posture deformation relative to the mobile robot main body. A mobile robot,
An obstacle detection unit that detects an obstacle and acquires position information of the obstacle;
A driving unit that drives the posture deforming member and deforms the posture;
A control unit for controlling the driving unit and the moving unit;
A tip position calculator that calculates position information of the tip of the posture deforming member;
A detection unit for detecting the moving direction and speed of the mobile robot body,
When the obstacle detection unit detects an obstacle and acquires its position information,
Based on the direction and speed of the mobile robot main body detected by the detection unit and the position information of the tip of the posture deforming member calculated by the tip position calculation unit, a moving speed and a movement direction of the mobile robot main body are determined. Calculating a first velocity vector and a second velocity vector defining a moving speed and moving direction relative to the mobile robot body of the tip,
The control unit obtains a speed component of a combined speed vector obtained by combining the first speed vector and the second speed vector in a direction in which the mobile robot body faces the obstacle,
Relative movement of the tip of the posture deforming member with respect to the obstacle rather than the time to reach the obstacle when the mobile robot body continues to move at the speed at which the first velocity vector is calculated. A mobile robot characterized in that the control unit controls the moving means and the drive unit so as to increase the time required until the speed becomes zero.   A maximum deceleration that decelerates the movement of the tip of the posture deforming member in a direction parallel to the combined velocity vector, a first deceleration that decelerates a speed component in the direction toward the obstacle of the mobile robot body, and the posture deformation 2. The control unit controls the moving unit and the driving unit by dividing the speed component in the direction toward the obstacle at the tip of the member into a second deceleration that decelerates. Mobile robot.   When the relative distance between the position of the tip and the position of the detected obstacle is equal to or less than a predetermined distance, the control unit increases the first deceleration to be greater than the second deceleration. The mobile robot according to claim 2, wherein the mobile means and the drive unit are controlled.   The mobile robot according to claim 1, further comprising an acceleration sensor that detects a change in acceleration caused by an external force.   The mobile robot according to any one of claims 1 to 4, further comprising a camera that visually acquires environmental information about a moving environment.   The posture deforming member is an arm part having one end attached to a mobile robot body, and includes at least one joint part between one end of the arm part and a tip of the arm part. Item 6. The mobile robot according to any one of Items 1 to 5.   The mobile robot according to claim 1, wherein the mobile robot moves in a plane. The mobile robot stores a movement map specified in a moving plane, and moves autonomously on the movement map;
On the stored movement map, the apparatus further comprises a movement route creation unit that creates a movement route based on the position information of the obstacle detected by the obstacle detection unit, and the movement means moves based on the created movement route. The mobile robot according to claim 1, wherein the robot main body is moved.   The mobile robot according to claim 8, wherein the movement map is a grid map created by virtually depicting grid lines connecting lattice points arranged at substantially constant intervals in the plane. .   The mobile robot according to claim 8 or 9, wherein the mobile robot body includes an absolute position acquisition unit that acquires an absolute position of the mobile robot body on the movement map.   The mobile robot according to any one of claims 8 to 10, wherein the mobile robot body includes a self-position calculating unit that calculates a self-position from a direction and a distance moved on a movement map.

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