JP2016085708A - Mobile body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mobile body being movable while detecting an object in the surroundings in which an operation of a position data acquisition portion can be checked even during movement of the mobile body.SOLUTION: A mobile body includes: a position data acquisition portion; an interference member; and a determination portion. The position data acquisition portion acquires a plurality of position data by detecting a reflection signal. The interference member is attached to a main body portion 1 so that at least a part is included in detection possible areas A1 and A2, and forms an interference image in a projection object image by reflecting a detection signal by at least a part of the interference member. The determination portion determines whether the interference image reflects at least a part of the interference member. The determination portion determines that the position data acquisition portion normally operates when determining that the interference image reflects at least a part of the interference member.SELECTED DRAWING: Figure 4B

Description

  The present invention relates to a movable body that can move while detecting an obstacle.

  Conventionally, a movable body that is movable while detecting an obstacle is known. For example, Patent Document 1 discloses a mobile robot including a traveling wheel, motor control means for driving the traveling wheel, and an ultrasonic sensor for detecting an obstacle. In this mobile robot, an ultrasonic wave is generated when the cover provided on the ultrasonic sensor is closed, and the ultrasonic sensor operates normally when the ultrasonic sensor detects the ultrasonic wave reflected by the cover. Judging that

Japanese Patent No. 3451723

  In the above-described mobile robot disclosed in Patent Document 1, the operation of confirming whether the ultrasonic sensor is operating normally is performed in a state where the ultrasonic sensor is covered with a cover. In this case, since the ultrasonic wave generated from the ultrasonic sensor is blocked by the cover, the obstacle cannot be detected by the ultrasonic sensor while the operation of the ultrasonic sensor is being confirmed. That is, in the mobile robot shown in Patent Document 1, the operation of the sensor cannot be confirmed while the mobile body is moving.

  An object of the present invention is to make it possible to check the operation of a sensor that detects an obstacle even when the moving body is moving, in a movable body that can move while detecting an obstacle.

Hereinafter, a plurality of modes will be described as means for solving the problems. These aspects can be arbitrarily combined as necessary.
The moving body according to an aspect of the present invention is a moving body that can move while detecting surrounding objects. The moving body includes a position data acquisition unit, an interference member, and a determination unit. The position data acquisition unit outputs a detection signal. The position data acquisition unit acquires a plurality of position data by detecting the reflected signal. The reflection signal is a signal generated when the detection signal is reflected by a surrounding object. The plurality of position data forms a projected object image obtained by projecting an object existing in the vicinity onto predetermined coordinates.

  The interference member is attached to the main body so that at least a part of the interference member is included in the detectable region. The main body portion forms the main body of the moving body. The detectable area is an area where the position data acquisition unit can acquire a plurality of position data. In addition, the interference member forms an interference image in the projection object image by reflecting the detection signal on at least a part of the interference member.

  The determination unit determines whether the interference image reflects at least a part of the interference member. Further, the determination unit determines that the position data acquisition unit is operating normally when it is determined that the interference image reflects at least a part of the interference member.

When the above moving body starts moving, the position data acquisition unit outputs a detection signal. The position data acquisition unit detects a reflection signal generated when the detection signal is reflected by an object present around the moving body. By detecting the reflected signal, the position data acquisition unit acquires a plurality of position data. Thereby, the moving body can travel while detecting surrounding objects.
At this time, since at least part of the interference member is included in the detectable region, the detection signal is reflected by at least part of the interference member. Therefore, when the position data acquisition unit is operating normally, the projection object image formed by the plurality of position data includes an interference image formed by the position data from the interference member. Position data from the interference member is obtained by detecting a reflection signal of the interference member.

  After acquiring the plurality of position data, the determination unit determines whether or not the interference image included in the projection object image reflects at least a part of the interference member. When it is determined that the interference image does not reflect at least a part of the interference member, such as when there is no interference image or the shape of the interference image does not correspond to the shape of at least a part of the interference member, It is determined that the data acquisition unit is operating abnormally.

  On the other hand, it is determined that the interference image reflects at least a part of the interference member, such as position data that forms the interference image exists, and the shape of the interference image corresponds to at least a part of the shape of the interference member. If it is determined, the determination unit determines that the position data acquisition unit is operating normally.

  In the above moving body, it is determined whether the position data acquisition unit is operating normally by determining whether the interference image reflects at least a part of the interference member. The position data that forms the interference image is included in the plurality of position data acquired during the movement of the moving body. Accordingly, the moving body can determine the operation state of the position data acquisition unit while detecting surrounding objects while moving.

  The interference member may have a predetermined shape. At this time, the determination unit determines whether the position data acquisition unit is operating normally by comparing the similarity with a predetermined threshold that can be appropriately changed. The similarity is a numerical value indicating the degree of coincidence between the shape of the interference image and the predetermined shape of the interference member. Thus, it can be determined whether or not the interference image reflects at least a part of the interference member based on the numerical value of similarity.

  The interference member may be at least a part of an attachment member for attaching the position data acquisition unit to the main body. Thereby, the moving body can confirm the attachment state of the position data acquisition unit.

  In a movable body that can move while detecting surrounding objects, the operation of the position data acquisition unit can be confirmed even while the movable body is moving.

The figure which shows the whole structure of an autonomous mobile body. The figure which shows typically the relationship between a detectable area | region and an interference member. The figure which shows the structure of a control part. The figure which shows typically the movement area | region and presence position of an autonomous mobile body. The figure which shows typically a detectable area | region and the projection object image obtained by the autonomous mobile body.

(1) Whole structure of autonomous mobile body Hereinafter, the autonomous mobile body of this invention is demonstrated. First, the whole structure of the autonomous mobile body 100 which concerns on 1st Embodiment is demonstrated using FIG. FIG. 1 is a diagram illustrating an overall configuration of an autonomous mobile body.
The autonomous mobile body 100 is a mobile body that autonomously travels on a predetermined scheduled travel route. The autonomous mobile body 100 mainly includes a main body unit 1, a traveling unit 2, a position data acquisition unit 3, a control unit 5, and an interference member 11. The main body 1 constitutes the main body of the autonomous mobile body 100.

  As shown in FIG. 1, the traveling unit 2 includes wheels 21 a and 21 b, and motors 23 a and 23 b (described later) so that the wheels 21 a and 21 b are in contact with a traveling surface such as a floor surface of a moving region S (described later). Is installed near the center of the bottom of the main body 1. The wheels 21 a and 21 b are attached to the output rotation shafts of the motors 23 a and 23 b installed on the left and right sides of the main body 1 so as to be rotatable around the output rotation shaft.

  The motors 23 a and 23 b receive drive signals (described later) from the control unit 5, and rotate the respective output rotation shafts according to the drive signals from the control unit 5. The wheels 21 a and 21 b rotate at a rotation amount and / or a rotation speed according to a drive signal from the control unit 5. The traveling unit 2 can move the main body 1 (that is, the autonomous mobile body 100) by the rotation of the wheels 21a and 21b. For example, an electric motor such as a brushless motor can be used as the motors 23a and 23b.

  In addition, a device for measuring the number of rotations (the amount of rotation) of each output rotation shaft of the motors 23a and 23b is attached to each output rotation shaft of the motors 23a and 23b. Then, the rotation amount of the output rotation shaft measured by the device is output to the control unit 5.

  The control unit 5 can calculate the rotation amounts of the wheels 21a and 21b based on the rotation amounts of the output rotation shafts of the motors 23a and 23b. As an apparatus for measuring the rotation amount of the output rotation shaft of the motors 23a, 23b, for example, an encoder can be used. For example, when the rotation amount of the output rotation shaft is measured using an incremental encoder, the rotation amount of the output rotation shaft can be measured as the number of pulses per predetermined time included in the pulse signal output from the encoder.

  The position data acquisition unit 3 coordinates an object (moving area S) where an autonomous moving body 100 moves an object such as an obstacle or a wall existing around the autonomous moving body 100 (hereinafter referred to as “moving coordinates”). An image projected on the screen (hereinafter referred to as “projected object image”) is acquired as a plurality of position data.

  The plurality of position data that can form the projected object image can be acquired by using, for example, a laser range finder (LRF) as the position data acquisition unit 3. In addition, a device that can measure the distance from the main body of an object around the main body, such as a ToF (Time of Flight) camera, can be used as the position data acquisition unit 3.

  When a laser range finder is used as the position data acquisition unit 3, a plurality of position data is obtained from, for example, a place on the predetermined one-dimensional plane of the object from the autonomous mobile body 100 (for example, a signal output from the laser range finder). As a two-dimensional data including a distance to the part of the surface of the object reflecting the object and a one-dimensional planar horizontal angle indicating the direction from the autonomous mobile object 100 where the object is located. Is done. In addition, when a ToF camera is used as the position data acquisition unit 3, a plurality of pieces of position data are obtained from, for example, a place on the predetermined two-dimensional plane of the above object from the autonomous mobile body 100 (for example, a signal output from the ToF camera). And a third order including a horizontal angle and a vertical angle on a two-dimensional plane indicating a direction from the autonomous mobile body 100 where the object location exists. Obtained as original data.

  The position data acquisition unit 3 such as a laser range finder rotates, for example, an output device of a detection signal (for example, laser light) provided in the position data acquisition unit 3 within a predetermined angle range in order to detect surrounding objects. By scanning, detection signals are output radially. The detection signal is reflected on the surface of the surrounding object. In the present embodiment, a signal generated when the detection signal is reflected by an object is called a reflected signal.

  The reflected signal is detected by, for example, rotationally scanning the reflected signal detector provided in the position data acquisition unit 3 within a predetermined angle range. Thereafter, the position data acquisition unit 3 acquires position data from the detected reflection signal.

  Therefore, when a plurality of position data is plotted on predetermined coordinates such as movement coordinates (described later), the shape (at least a part) of the object (surface) existing around the autonomous mobile body 100 in the movement area S moves. Projected to coordinates. That is, the plurality of position data forms a projected object image that projects an object existing around the autonomous mobile body 100 on the movement coordinates.

  In the present embodiment, the position data obtained by the position data acquisition unit 3 is subjected to coordinate conversion on the movement coordinates representing the movement area S (FIGS. 4A and 4B) of the autonomous mobile body 100. Specifically, the position data obtained by the position data acquisition unit 3 is converted into movement coordinates (for example, XY coordinates for two dimensions, XY-times for three dimensions) that represent a position in the movement area S. Convert to position data on the Z coordinate).

  As shown in FIG. 1, the position data acquisition unit 3 includes a front data acquisition unit 31 and a rear data acquisition unit 33. The front data acquisition unit 31 is attached in front of the autonomous mobile body 100 and can acquire position data from an object existing in front of the autonomous mobile body 100. On the other hand, the rear data acquisition unit 33 is attached to the rear of the autonomous mobile body 100 in the traveling direction, and can acquire position data from an object existing behind the autonomous mobile body 100.

  In the present embodiment, the position data obtainable range (detectable area A1 (FIG. 2)) of the front data obtaining unit 31 is the position data obtainable area (detectable area A2 (FIG. 2)) of the rear data obtaining unit 33. Is wider than. For example, in the present embodiment, the rear data acquisition unit 33 can detect an object in a range of about 180 ° behind the autonomous mobile body 100 having a radius of about 10 m with the rear data acquisition unit 33 as the center, while the front data acquisition unit 31 can detect an object existing in a range of about 270 ° in front of the autonomous mobile body 100 having a radius of about 30 m with the front data acquisition unit 31 as the center.

  Thereby, the position data acquisition unit 3 can detect an object existing in a wider range centering on the autonomous mobile body 100 (particularly in front of the autonomous mobile body 100). Note that the object detection range of the front data acquisition unit 31 and the object detection range of the rear data acquisition unit 33 are not limited to the detection range described above, and an appropriate detection range can be set as necessary.

  Moreover, in this embodiment, the front data acquisition part 31 and / or the back data acquisition part 33 are attached to the upper direction (the front and back) of the said main-body part 1 in the vertical direction. Thereby, for example, when an object installed on the floor surface of the moving area S frequently moves, a projection formed by a plurality of position data acquired by the front data acquisition unit 31 and the rear data acquisition unit 33. It is possible to eliminate as much as possible the influence of a temporal change in the object image (particularly, a change in which an object existing at one time does not exist at another time).

  In the conventional technique, when the object installed in the movement area S is frequently moved, the projected object image before the movement of the autonomous mobile body 100 may be greatly different from the projected object image after the movement. If the projected object images are largely different before and after the movement, no matter how one of the projected object images before and after the movement is moved, it does not coincide with the other projected object image. In this case, for example, when the movement amount of the autonomous mobile body 100 is estimated using a plurality of position data or the position of the autonomous mobile body 100 is estimated using a plurality of position data, the estimation of the movement amount or the position is performed. It becomes difficult.

  Further, in the conventional technology, when the projected object image before and after the movement is greatly different, even if it is determined that the moved projected object image matches the reference projected object image, the moved projected object image is moved. The movement amount or the estimated position of the autonomous mobile body 100 estimated from the amount may be far from the actual movement amount of the autonomous mobile body 100 in some cases. That is, there may be a large error between the movement amount or estimated position of the autonomous mobile body 100 estimated based on a plurality of position data and the actual movement amount or position of the autonomous mobile body 100.

  In order to solve those problems, in this embodiment, as described above, the front data acquisition unit 31 and / or the rear data acquisition unit 33 is installed on the upper part of the main body unit 1 to detect an object that moves rapidly. The possibility is reduced. As a result, by using the plurality of position data acquired by the front data acquisition unit 31 and the rear data acquisition unit 33 (position data acquisition unit 3), the movement of the autonomous mobile body 100 can be accurately performed without causing a large error. The amount and position can be estimated.

The control unit 5 controls the traveling unit 2. Specifically, the control unit 5 estimates the current position of the autonomous mobile body 100 based on a plurality of position data acquired by the position data acquisition unit 3.
Further, the control unit 5 autonomously moves from the estimated current position to a predetermined target position (or one of a plurality of target positions) stored in a storage unit (described later) of the control unit 5. A control signal for moving 100 is calculated, a drive signal for driving the traveling unit 2 is calculated based on the control signal, and output to the traveling unit 2 (motors 23a and 23b).

  As described above, in order to estimate the current position of the autonomous mobile body 100 using the plurality of position data acquired by the position data acquisition unit 3, the control unit 5 further receives the position data by the position data acquisition unit 3. Determine whether it is properly acquired (that is, whether it is operating normally). The detailed configuration of the control unit 5 will be described later.

  As shown in FIG. 1, the interference member 11 is composed of a plurality of rod-shaped members. The interference member 11 is formed as at least a part of an attachment member (not shown) for attaching the position data acquisition unit 3 (the front data acquisition unit 31 and the rear data acquisition unit 33) to the main body unit 1. For example, the bar-shaped portion formed integrally with the attachment member can be the interference member 11. Since the attachment member is attached to the main body 1, it can be said that the interference member 11 is attached to the main body 1.

If the mounting state of the position data acquisition unit 3 changes due to a collision or vibration, the relative positional relationship between the position data acquisition unit 3 and the mounting member may be shifted. Thereby, the relative positional relationship between the position data acquisition unit 3 and the interference member 11 is shifted. This is because the interference member 11 is formed integrally with the mounting member.
When the relative positional relationship between the position data acquisition unit 3 and the interference member 11 is deviated as described above, the shape of the obtained interference image (FIG. 4B) changes before and after the change of the attachment state.

  As will be described later, the determination unit 55 (FIG. 3) determines the degree of coincidence (similarity (described later)) between the shape of the interference image and the shape of at least a part of the interference member 11. Thereby, the determination part 55 can detect the change of the attachment state of the position data acquisition part 3 as a change of the value of similarity. As a result, the determination unit 55 can determine that the attachment state of the position data acquisition unit 3 is abnormal when it is determined that the attachment state has changed and the similarity is below a predetermined threshold that can be appropriately changed.

  Further, as shown in FIG. 1, the interference member 11 attached to the front data acquisition unit 31 is configured as two rod-like members extending at a predetermined angle with respect to the front direction of the autonomous mobile body 100. Has been. On the other hand, the interference member 11 attached to the rear data acquisition unit 33 is configured as two rod-like members extending at a predetermined angle with respect to the direction opposite to the front direction of the autonomous mobile body 100. .

  Further, as shown in FIG. 2, at least a part of the rod-shaped member constituting the interference member 11 is divided into a detectable area A1 of the front data acquisition unit 31 and a detectable area A2 of the rear data acquisition unit 33. included. FIG. 2 is a diagram schematically illustrating the relationship between the detectable region and the interference member.

  Thereby, the interference member 11 can reflect the detection signals from the front data acquisition unit 31 and the rear data acquisition unit 33. Then, the reflected signal generated by reflecting the detection signal by the interference member 11 is detected by the front data acquisition unit 31 and the rear data acquisition unit 33.

  As a result, when the front data acquisition unit 31 and the rear data acquisition unit 33 are operating normally, the projected object image formed by the plurality of position data acquired by the front data acquisition unit 31 and the rear data acquisition unit 33 , An image (interference image) corresponding to at least a part of the interference member 11 is included.

  Moreover, as shown in FIG.1 and FIG.2, the two interference members 11 attached to the front data acquisition part 31 have a predetermined angle (an example of a predetermined shape). For this reason, the plurality of position data obtained from the two interference members 11 attached to the front data acquisition unit 31 have an inverted V shape (in the case of FIGS. 1 and 2) spreading in the forward direction of the autonomous mobile body 100. An interference image is formed.

  On the other hand, the two interference members 11 attached to the rear data acquisition unit 33 also have a predetermined angle. For this reason, a plurality of position data obtained from the two interference members 11 attached to the rear data acquisition unit 33 is V-shaped (in FIGS. 1 and 2) spreading in a direction opposite to the front direction of the autonomous mobile body 100. The interference image is formed.

  When the autonomous mobile body 100 has the above configuration, the autonomous mobile body 100 can estimate the presence position in the movement area S using a plurality of position data acquired by the position data acquisition unit 3. Since the autonomous mobile body 100 can estimate the position of the main body, the autonomous mobile body 100 can autonomously travel on a predetermined travel route by generating a control signal that moves from the current position to a predetermined target position. In other words, the autonomous mobile body 100 can autonomously move along a predetermined travel route while detecting an object (such as an obstacle) existing in the vicinity.

  In addition, since the autonomous mobile body 100 includes the interference member 11, the autonomous mobile body 100 can detect a reflection signal from the interference member 11 while detecting a surrounding object. As a result, whether or not the position data acquisition unit 3 is operating normally is determined based on whether or not the reflected signal from the interference member 11 is properly detected not only when the autonomous mobile body 100 is moving but also when it is moving. it can.

  As shown in FIG. 1, the autonomous mobile body 100 of the first embodiment further includes an operation unit 7 attached to the main body 1 via an attachment member 9. As shown in FIG. 1, the operation unit 7 includes rotatable operation handles 71 a and 71 b, and each operation amount (rotation amount) of the operation handles 71 a and 71 b can be output to the control unit 5. . Thereby, the control part 5 becomes possible [calculating the drive signal which controls the motors 23a and 23b according to the operation amount of the operation handles 71a and 71b].

  When the autonomous mobile body 100 includes the operation unit 7 described above, the operator can operate the autonomous mobile body 100. Specifically, the operator can operate the autonomous mobile body 100 by adjusting the rotation amount and the rotation speed of the wheels 21a and 21b by rotating the operation handles 71a and 71b by the operator.

  Further, as described above, the control unit 5 can estimate the position of the autonomous mobile body 100 in the movement region S. Therefore, for example, when the operator operates the autonomous mobile body 100 using the operation unit 7, the position of the autonomous mobile body 100 is estimated at a predetermined time interval, and the estimated position is stored in the storage device of the control unit 5. For example, the operation of the autonomous mobile body 100 by the operator can be taught to the autonomous mobile body 100 (control unit 5) as the predetermined travel route.

  The method of teaching the travel route to the autonomous mobile body 100 is the above-described method of estimating and storing the position of the autonomous mobile body 100 while the operator operates the autonomous mobile body 100 using the operation unit 7. Not limited. For example, in the data storing the coordinate points on the movement coordinates representing the movement area S, the travel route is taught to the autonomous mobile body 100 by directly operating (or directly inputting) the values indicating the coordinate points. it can. Alternatively, the traveling route can be taught to the autonomous mobile body 100 by another method for designating the position (the coordinate value of the movement coordinate) in the movement area S of the autonomous mobile body 100.

  The autonomous mobile body 100 of the first embodiment further includes an auxiliary wheel unit 8. The auxiliary wheel portion 8 has two auxiliary wheels 8a and 8b. The two auxiliary wheels 8a and 8b are attached to the rear bottom of the main body 1 so that they can rotate independently. By providing the auxiliary wheel part 8, the autonomous mobile body 100 can move stably and smoothly.

(2) Configuration of Control Unit Next, the configuration of the control unit 5 will be described with reference to FIG. FIG. 3 is a diagram illustrating a configuration of the control unit. The control unit 5 performs signal conversion with a storage device including a CPU (Central Processing Unit), a hard disk device, a ROM (Read Only Memory), a RAM (Random Access Memory), a storage medium reading device, and the like. It can be realized by a microcomputer system equipped with an interface. In addition, some or all of the functions of the respective units of the control unit 5 described below may be realized as a program. Further, the program may be stored in a storage device of the microcomputer board. Alternatively, some or all of the functions of the respective units of the control unit 5 may be realized by a custom IC or the like.

  The control unit 5 includes a position estimation unit 51, a travel control unit 53, and a determination unit 55. The position estimation unit 51 estimates the presence position of the autonomous mobile body 100 in the movement area S. In the present embodiment, the position estimation unit 51 uses the SLAM (Simultaneous Localization and Mapping) method or the like to connect an object such as a wall or an obstacle around the autonomous mobile body 100 present at the current position with the autonomous mobile body 100. Map information (global map) indicating map information (local map) indicating a relative positional relationship and a movement area S (a part including at least the area where the autonomous mobile body 100 moves) stored in advance. The current position of the autonomous mobile body 100 is estimated based on the map matching result with the environmental map.

  Further, the position estimation unit 51 can receive a pulse signal from the encoders of the motors 23a and 23b. Thereby, the position estimation part 51 can calculate the rotation amount of the wheels 21a and 21b based on the pulse signals of the motors 23a and 23b. For example, the rotation amount of the wheels 21a and 21b can be calculated from the number of pulses included in the pulse signals from the motors 23a and 23b.

  Further, the position estimation unit 51 calculates the wheel movement amount based on the rotation amounts of the wheels 21a and 21b. The wheel movement amount is the movement amount of the autonomous mobile body 100 due to the rotation of the wheels 21a and 21b. Thereby, the position estimation part 51 can perform map matching in consideration of both the map information obtained from the position data and the wheel movement amount. As a result, the position estimation unit 51 can accurately estimate the position of the autonomous mobile body 100 even if the acquired position data includes an error.

  When the autonomous mobile body 100 moves autonomously, the traveling control unit 53 moves the autonomous mobile body 100 from a current position to a predetermined movement route stored in a storage device of the control unit 5 or the like. The traveling unit 2 is controlled so as to travel to the target position.

  Specifically, the travel control unit 53 first autonomously operates at a predetermined speed and / or acceleration from the current position to the predetermined target position based on the distance and direction from the current position to the predetermined target position. A control command for moving the moving body 100 is generated. Next, the traveling control unit 53 calculates a drive signal for controlling the motors 23a and 23b based on the control command and outputs the drive signal to the motors 23a and 23b.

In the present embodiment, the travel control unit 53 outputs drive signals individually to the motors 23a and 23b. That is, the motors 23a and 23b can rotate at different rotational speeds. For example, when it is desired to move the autonomous mobile body 100 straight, the motors 23a and 23b are rotated at the same rotational speed. On the other hand, when the motors 23a and 23b are rotated at different rotational speeds, the autonomous mobile body 100 can rotate.
As in the traveling unit 2 shown in FIG. 1, a traveling unit that travels by rotating the two wheels 21a and 21b individually by the motors 23a and 23b may be referred to as a “differential two-wheeled” traveling unit. is there.

  In addition, the travel control unit 53 inputs the rotation amounts (operation amounts) of the operation handles 71a and 71b from the operation unit 7, calculates the drive signal from the input rotation amounts, and can output the drive signals to the motors 23a and 23b. ing. Thereby, the autonomous mobile body 100 can be operated by an operator who operates the operation handles 71a and 71b.

  As the traveling control unit 53, for example, a control device using a feedback control theory can be used. When a control device using feedback control theory is used as the travel control unit 53, the travel control unit 53 inputs a pulse signal from an encoder or the like attached to the output rotation shaft of the motors 23a and 23b, and the motors 23a and 23b. The rotation speed can be controlled as indicated in the control command.

  The determination unit 55 acquires a plurality of position data from the position data acquisition unit 3, and determines whether or not position data that forms an interference image exists in the projection object image formed by the plurality of position data. That is, the determination unit 55 determines whether or not an interference image is included in the projected object image. If it is determined that no interference image is included in the projected object image, the determination unit 55 determines that the position data acquisition unit 3 is not operating normally.

  Further, the determination unit 55 determines whether or not the interference image reflects a portion (an example of at least a part of the interference member 11) included in the detectable areas A1 and A2 of the interference member 11. Specifically, the determination unit 55 determines whether or not a shape corresponding to the V shape or the inverted V shape formed by the two interference members 11 is also seen in the interference image.

  In the present embodiment, the determination unit 55 determines whether the interference image reflects the shape of the interference member 11 based on a numerical value (similarity) indicating the degree of coincidence between the shape of the interference image and the shape of the interference member 11. to decide. For example, when the similarity exceeds a predetermined threshold that can be changed as appropriate, the determination unit 55 matches the shape of the interference image with the shape of the interference member 11 (that is, the interference image reflects the shape of the interference member 11). It is judged).

  As a method for digitizing the degree of coincidence between the shape of the interference image and the shape of the interference member 11, for example, pattern matching of a projected object image formed by a plurality of position data can be used. As a pattern matching method for a projected object image formed by a plurality of position data, for example, there is template matching.

  For example, the template matching is a difference between the distance of one position data of a group of position data and the distance of one position data of the same position as the position of the one position data of the other groups of position data. The absolute value of (point distance) is summed by a predetermined number determined by the number of position data. Then, based on SAD (Sum of Absolute Difference) which is the sum of the absolute values of the distances (differences) between the points obtained by summing up the absolute values of the distances between the points, a projection object formed from a group of position data This is a method for determining the degree of coincidence between an image and a projected object image formed by position data of another group.

  Therefore, when examining the degree of coincidence between the interference image and the shape of the interference member 11 using template matching, for example, a plurality of model position data and a plurality of interference position data stored in the storage device of the control unit 5 or the like. A numerical value (referred to as similarity) for determining the degree of coincidence between the interference image and the shape of the interference member 11 can be calculated using the SAD calculated using the above as an index. The plurality of model position data forms a projection object image (model image) obtained by projecting at least a part of the interference member 11 on the moving coordinates. The interference position data is position data that forms an interference image.

  In template matching, it is determined that the smaller the SAD is, the more consistent the interference image and the shape of the interference member 11 are. This is because a small SAD means that a plurality of model position data and a plurality of interference position data exist at close positions as a whole. Therefore, in the present embodiment, the similarity is expressed as a function of SAD based on a function in which the similarity (output) increases as SAD (input) decreases.

As described above, when the determination unit 55 determines the degree of coincidence between the interference image and the shape of the interference member 11 by pattern matching, various abnormalities of the position data acquisition unit 3 other than the abnormality that the position data is not acquired. Can be detected.
For example, the displacement of the position data acquisition unit 3 and the displacement of the direction, the presence of another object (for example, the wiring material of the autonomous mobile body 100) in the detectable region of the position data acquisition unit 3, the position data acquisition unit 3 It is possible to detect an abnormality in the position data acquisition unit 3 such that the projection object image (interference image) is distorted or deformed, such as contamination of the signal detection unit and / or an abnormality in gain setting of the position data acquisition unit 3.

  Further, when the determination unit 55 determines that the position data acquisition unit 3 is not operating normally, the position data acquisition unit 3 is abnormal in a display unit (not shown) provided in the autonomous mobile body 100. Display to notify that there is. Alternatively, the determination unit 55 may notify an external computer or the like that the position data acquisition unit 3 is abnormal, or may instruct the autonomous mobile body 100 to generate sound.

  In addition, when it is determined that the position data acquisition unit 3 is not operating normally, the determination unit 55 causes the position estimation unit 51 to stop using the position data acquired from the position data acquisition unit 3. You may order. In this case, the position estimation unit 51 can estimate the position of the autonomous mobile body 100 using information such as the position and distance obtained by other means (for example, the rotation amounts of the wheels 21a and 21b).

  When the control unit 5 has the above-described configuration, the autonomous mobile body 100 can autonomously move on a predetermined travel route such as a travel route stored in a storage device or the like of the control unit 5. In addition, since the control unit 5 includes the determination unit 55 described above, in the control unit 5 of the present embodiment, in addition to the abnormality that the position data acquisition unit 3 has not acquired the position data, the other above-described items An abnormality in the position data acquisition unit 3 can also be detected.

(3) Operation of autonomous mobile body Next, the operation of the autonomous mobile body 100 will be described. In the following description, an operation when the autonomous mobile body 100 autonomously moves along a predetermined route while passing through a predetermined target position will be described. In the following description, as shown in FIG. 4A, an operation in the case where the moving region S defined by the wall W is moved from the position P1 to the position P2 will be described. FIG. 4 is a diagram schematically showing the movement area and the existence position of the autonomous mobile body.
When the autonomous mobile body 100 starts operation (movement), the position data acquisition unit 3 outputs a detection signal. In addition, the position data acquisition unit 3 detects a reflection signal generated when the detection signal is reflected by an object such as a wall or an obstacle existing around the autonomous mobile body 100, and acquires a plurality of position data.

  At this time, in the autonomous mobile body 100 present at the position P1, a plurality of position data forming a projected object image (shown by a thick line) as shown in FIG. 4B is obtained. FIG. 4B is a diagram schematically showing a detectable region and a projected object image obtained by an autonomous mobile body. That is, the projection object image by the reflected signal from the part included in the detectable area A1 of the right wall W of the autonomous mobile body 100 and the parts included in the detectable areas A1 and A2 of the lower wall W of the paper. Position data acquisition unit 3 obtains position data for forming a projected object image based on the reflection signal.

  In addition to the projected object image from the wall, the position data acquisition unit 3 acquires position data that forms an interference image by reflection signals from portions included in the detectable areas A1 and A2 of the interference member 11.

  After acquiring a plurality of position data (interference image and / or projection object image), the determination unit 55 determines whether or not position data for forming an interference image is included in the acquired plurality of position data. When it is determined that position data that forms an interference image is included, the determination unit 55 determines that the position data acquisition unit 3 can acquire at least position data.

  On the other hand, when it is determined that position data for forming an interference image is not obtained (position data is hardly obtained), the determination unit 55 has an abnormality in the position data acquisition unit 3 (position It is determined that the data has not been acquired. And the judgment part 55 outputs the signal etc. which notify abnormality.

  Further, the determination unit 55 calculates the similarity between the interference image formed by the obtained position data and the model image formed by the plurality of model position data (that is, an image representing the shape of the interference member 11). .

  When the determination unit 55 performs pattern matching by template matching, the determination unit 55 calculates a similarity based on SAD between a plurality of model position data and interference position data forming an interference image. Thereafter, the determination unit 55 determines that the interference image reflects a portion included in the detectable areas A1 and A2 of the interference member 11 when the similarity exceeds a predetermined threshold. That is, the determination unit 55 determines that the position data acquisition unit 3 is operating normally.

  On the other hand, when the similarity is equal to or less than the predetermined threshold, the determination unit 55 determines that the position data acquisition unit 3 has acquired the position data but is not operating normally. Thereby, the determination part 55 can detect the state of the position data acquisition part 3 which should determine that it is operating abnormally even if said position data is acquired.

Even when the autonomous mobile body 100 moves from the position P1 and reaches the position P2, the autonomous mobile body 100 acquires position data from the position data acquisition unit 3 as described above. However, at the position P2, the wall W of the moving area S does not exist in the range of the detectable areas A1 and A2.
In a conventional autonomous mobile body that does not include an interference member, no position data can be obtained at the position P2. Therefore, a conventional autonomous mobile body that does not include an interference member cannot determine whether there is an abnormality in the position data acquisition unit 3 at the position P2 or whether the position data cannot be acquired without a wall or an obstacle.

  Or, in particular, at the position P2, in order to determine the reason why the position data cannot be acquired, in the conventional autonomous mobile body, a shutter or the like is installed in front of the position data acquisition unit, and the signal reflected by the shutter can be detected. It was necessary to judge whether or not. That is, in the conventional autonomous mobile body, it is necessary to stop the acquisition of position data for generating map information or the like in order to determine the reason why the position data cannot be acquired.

  On the other hand, in the autonomous mobile body 100 of the present embodiment, as shown in FIG. 4B, the position data acquisition unit 3 operates normally even if the walls W and obstacles of the moving area S are not present in the detectable areas A1 and A2. If there is, position data for forming an interference image is acquired. That is, in the autonomous mobile body 100 of this embodiment, when position data acquisition unit 3 cannot acquire (or almost) position data, it can be determined that there is an abnormality that position data cannot be acquired in position data acquisition unit 3.

  As shown in FIG. 4B, in the autonomous mobile body 100 of the present embodiment, an interference image from the interference member 11 and a projection object image from a wall W or an obstacle existing in the movement region S are obtained simultaneously. It is done. That is, the autonomous mobile body 100 according to the present embodiment can detect an abnormality in the position data acquisition unit 3 while detecting an object present in the moving region S.

  Furthermore, in the autonomous mobile body 100 of the present embodiment, even if only position data that forms an interference image is acquired at the position P2, the determination unit 55 is not able to acquire position data by the above pattern matching. Can be determined at the position P2.

  As described above, in the autonomous mobile body 100 of the present embodiment including the interference member 11, even when no walls or obstacles exist in the detectable areas A1 and A2, the detection of the obstacle is stopped during the movement. Therefore, it can be determined whether or not the position data acquisition unit 3 is operating normally. Furthermore, by determining whether or not the interference image formed by the position data reflects the shape of the interference member 11, the determination unit 55 can determine the type and cause of the abnormality occurring in the position data acquisition unit 3.

  In the autonomous mobile body 100 of the present embodiment, the position data is converted into coordinate values on the movement coordinates representing the movement area S after being acquired by the position data acquisition unit 3. In this case, depending on the posture (traveling direction) of the autonomous mobile body 100 in the moving region S, the direction (shape) of the interference image formed by the position data after coordinate conversion differs between the position P1 and the position P2 (FIG. 4B).

  For this reason, in the present embodiment, before pattern matching between the model image and the interference image, based on the movement amount of the autonomous mobile body 100 estimated using the position data and / or the rotation amount of the wheels 21a and 21b. Then, the model image (model position data) is moved to generate a new model image (moving model image). After generating the moving model image, the determination unit 55 performs pattern matching between the moving model image and the interference image.

(4) Other Embodiments Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications can be made without departing from the scope of the invention. In particular, a plurality of embodiments and modifications described in this specification can be arbitrarily combined as necessary.

(A) Other embodiment of interference member In said 1st Embodiment, although the interference member 11 was comprised by the rod-shaped member, it is not restricted to this. You may comprise the interference member 11 with the member of other arbitrary shapes. In this case, the shape of the member is preferably a shape that can reflect the shape of the member in the interference image formed by the position data obtained from the reflected signal.

  In the first embodiment, the interference member 11 is formed integrally with the attachment member of the position data acquisition unit 3. That is, the position of the interference member 11 is fixed. However, the present invention is not limited to this, and the interference member 11 may be movable. For example, by moving the interference member 11 in the area of the signal detection window (detectable areas A1 and A2) of the position data acquisition unit 3, it is determined which position data is not acquired, which direction Information regarding an abnormality that has occurred in a part of the position data acquisition unit 3, such as whether the interference image (projected object image) is distorted, can be detected.

  Furthermore, the interference member 11 may be movable so as to be included in the detectable regions A1 and A2 only when position data can hardly be acquired by the position data acquisition unit 3. Thereby, the possibility that the interference member 11 collides with an object such as an object or a person in the moving region S can be reduced.

(B) Other Embodiments for Similarity In the first embodiment described above, the similarity matches the interference image and the image formed by the model position data (an image that is at least a part of the interference member 11). The SAD is defined as a function of SAD based on a function in which the similarity (output) increases as SAD (input) decreases, using SAD with a smaller value as an index. However, the present invention is not limited to this, and the similarity may be defined using another index.

  For example, an index function whose value increases as the interference image matches the image formed by the model position data may be defined as similarity. For example, one point data position at the same position as the position of the one point data position data among the distance of one point data position data of the group of point data position data and the other point data position data of the other group I-SSD (Inverted-Sum of Squared Difference), which is the reciprocal of a value calculated by adding the square value of the difference (distance between points) of the data to a predetermined number determined by the number of point data position data. ) May be used as an index. That is, a large I-SSD means that a plurality of model position data and a plurality of interference position data are present at close positions as a whole. Therefore, the similarity may be defined by using I-SSD as an index and defining a function that increases the similarity as I-SSD increases.

  In addition, the “predetermined threshold value” that is a criterion for determining whether or not the interference image and the shape of the interference member 11 coincide with each other is a definition of the similarity and / or what value the similarity becomes to be the interference image. The interference member 11 may be changed as appropriate depending on whether or not it is determined that the shapes of the interference members 11 match.

  Further, the “predetermined threshold value” may be appropriately changed according to a predetermined condition during the operation of the autonomous mobile body 100. For example, the predetermined threshold is increased as the cumulative moving distance and / or cumulative operating time of the autonomous mobile body 100 becomes longer (that is, the condition for determining that the interference image and the image formed by the model position data match) (Strictly). In this case, since the probability that an abnormality will occur in the position data acquisition unit 3 increases as the accumulated moving distance and / or accumulated operation time of the autonomous mobile body 100 increases, the abnormality is detected early by increasing the threshold value. Expected effects. Also, when an abnormality is detected and the cause is repaired, or when the position data acquisition unit 3 returns to a more normal state due to regular maintenance of the autonomous mobile body 100, the predetermined threshold value is set to a small value. It may be changed again.

  The present invention can be widely applied to a movable body that can move while detecting an obstacle.

DESCRIPTION OF SYMBOLS 100 Autonomous mobile body 1 Main-body part 2 Traveling part 21a, 21b Wheel 23a, 23b Motor 3 Position data acquisition part 31 Front data acquisition part 33 Back data acquisition part 5 Control part 51 Position estimation part 53 Travel control part 55 Judgment part 7 Operation part 71a, 71b Operation handle 8 Auxiliary wheel portion 8a, 8b Auxiliary wheel 9 Mounting member 11 Interference member A1, A2 Detectable area S Moving area W Wall

Claims (3)

A movable body that can move while detecting surrounding objects,
A plurality of position data forming a projected object image by projecting the object onto a predetermined coordinate by outputting a detection signal and detecting a reflection signal generated by the detection signal being reflected by the surrounding object A position data acquisition unit for acquiring
The projection object is attached to the main body so that at least a part is included in the detectable region in which the position data acquisition unit can acquire the plurality of position data, and the detection signal is reflected at the at least part. An interference member for forming an interference image in the image;
A determination unit that determines that the position data acquisition unit is operating normally when it is determined that the interference image reflects the at least part of the interference member;
A moving object comprising: The interference member has a predetermined shape;
The determination unit compares the similarity, which is a numerical value indicating the degree of coincidence between the shape of the interference image and the predetermined shape of the interference member, with a predetermined threshold that can be appropriately changed, so that the interference image is The moving body according to claim 1, wherein it is determined whether or not at least a part of the interference member is reflected.   The moving body according to claim 1, wherein the interference member is at least a part of an attachment member for attaching the position data acquisition unit to the main body.

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