Traveling vehicle and traveling vehicle system

Abstract

To provide a traveling vehicle that has improved accuracy of autonomous movement to a target point.SOLUTION: A traveling vehicle 12 autonomously moves to a target point. The traveling vehicle 12 moves on the basis of a large-size marker 36 and a small-size marker 37 installed at the target point. A control unit of the traveling vehicle executes, at a position where the traveling vehicle 12 is separate from the target point, image processing on images of the large-size marker 36 and the small-size marker 37 photographed by an image acquisition unit 25 of the traveling vehicle 12, recognizes the relative posture of the traveling vehicle 12 to the large-size marker 36, and recognizes the relative position of the traveling vehicle 12 to the small-size marker 37. The control unit creates a traveling track for moving the traveling vehicle to the target point from the recognized relative posture and relative position of the traveling vehicle 12, and the traveling vehicle 12 moves along the traveling track. The control unit executes image processing on the photographed image of the small-size maker 37 in a state where the traveling vehicle 12 is near the target point, and recognizes the relative position and the relative posture of the traveling vehicle 12 on the basis of the small-size marker 37.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a traveling vehicle that autonomously moves to a target point, and a traveling vehicle system that causes the traveling vehicle that autonomously moves to the target point to reach the target point.

Background Art

[0002] Conventionally, as described in Patent Document 1, for example, a camera installed on a traveling vehicle such as a robot captures a marker installed at a target point, thereby recognizing the relative position and orientation of the traveling vehicle with respect to the marker, generating a traveling trajectory of the traveling vehicle from the recognized relative position and orientation, and approaching the traveling vehicle toward the target point. There is a known technique.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above-described technology, the recognition accuracy of the relative position and orientation of the marker and the traveling vehicle depends on the size of the marker in the captured image. That is, if the size of the marker is increased, the size of the marker in the captured image also increases even when the traveling vehicle and the marker are separated by a long distance, so the recognition accuracy of the relative position and orientation of the traveling vehicle is improved. However, when the traveling vehicle travels in the direction approaching the marker, the marker goes out of the field of view of the camera of the traveling vehicle, so that the marker cannot be recognized and the movement to the target point becomes difficult.

[0005] An object of the present invention is to provide a traveling vehicle and a traveling vehicle system with improved accuracy of autonomous movement to a target point.

Means for Solving the Problems

[0006] The traveling vehicle of the present invention is a traveling vehicle that autonomously moves to a target point, and includes a main body, a drive unit installed on the main body for moving the main body, an image acquisition unit installed on the main body for photographing the outside of the main body, and a control device connected to the drive unit and the image acquisition unit for executing output of a drive command for the drive unit and image processing of an image acquired by the image acquisition unit. In a target movement operation of moving the traveling vehicle based on markers including at least a first marker arranged side by side corresponding to the target point and a second marker having a higher recognition accuracy of relative posture than the first marker in an image acquired by the image acquisition unit at a position away from the target point, when the traveling vehicle is at a position away from the target point, image processing is performed on an image of the second marker and / or the first marker included in an image photographed by the image acquisition unit of the traveling vehicle to recognize the relative posture of the traveling vehicle with respect to the second marker and recognize the relative position of the traveling vehicle with respect to the second marker or the first marker. A traveling trajectory for moving to the target point is generated from the recognized relative posture and relative position of the traveling vehicle, and the drive unit is driven so that the traveling vehicle moves along the traveling trajectory. When the traveling vehicle is at a position close to the target point, image processing is performed on a photographed image of the first marker to recognize the relative position and relative posture of the traveling vehicle based on the first marker.

Effect of the Invention

[0007] According to the present invention, it is possible to provide a traveling vehicle and a traveling vehicle system with improved accuracy of autonomous movement to a target point.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying out the Invention

[0009] Hereinafter, the first embodiment of the present invention will be described with reference to FIGS. 1 to 5.

[0010] FIG. 1 shows a traveling vehicle system 10. The traveling vehicle system 10 includes a traveling vehicle 12 that autonomously moves on the floor surface 11 in the facility to a target point.

[0011] The traveling vehicle 12 includes, for example, an unmanned transport vehicle that carries a transported object or pulls a towing object such as a cart or a dolly and transports it from a predetermined transport source to a transport destination. Further, the traveling vehicle system 10 includes a power supply station 14 that is one of the stop stations 13 as a target point of the traveling vehicle 12. The traveling vehicle system 10 includes a plurality of traveling vehicles 12 and a plurality of power supply stations 14 installed at a plurality of locations.

[0012] The traveling vehicle 12 includes a main body 20, two drive wheels 21 for moving the main body 20, and a plurality of driven wheels 22. The traveling vehicle 12 has one direction as the forward direction and the opposite other direction as the backward direction. Two drive wheels 21 are installed on both sides in the left - right direction intersecting the forward and backward directions, and driven wheels 22 are respectively installed in the front - rear direction of the drive wheels 21 on both sides. The drive wheels 21 on both sides can be individually rotationally driven in the forward and backward directions, and the driven wheels 22 are composed of casters or the like whose direction in the moving direction can freely change. By combining the rotation directions of the drive wheels 21 on both sides, the traveling vehicle 12 can move forward, move backward, move in a curve, spin - rotate (turn on the spot), etc.

[0013] The traveling vehicle 12 further includes a power - receiving pad 24 installed above the front surface 23 (or the rear surface in the backward direction) of the main body 20 in the forward direction, and an image - acquisition unit 25 installed below the front surface 23 of the main body 20. Note that the front surface 23 of the main body 20 is formed in the same plane in the vertical direction.

[0014] The power - receiving pad 24 can receive power by a non - contact power - supply method such as an electromagnetic induction method or an electric - field coupling method. The power - receiving pad 24 is formed in a pad shape with a built - in power - receiving coil corresponding to, for example, the electromagnetic induction method.

[0015] The image - acquisition unit 25 is a camera that photographs the external world in front of the traveling vehicle 12 and has a predetermined visual field 26 in the vertical and horizontal directions (photographed images corresponding to the visual field 26 are shown in FIGS. 5(a) and (b)). The image - acquisition unit 25 is installed on the main body 20 such that the lower - end portion (lower side) in the range of the vertical visual - field angle α in the visual field 26 is located substantially horizontally and the center line 27 of the vertical visual - field angle α in the visual field 26 faces upward.

[0016] Further, the power supply station 14 supplies power for charging the battery of the traveling vehicle 12. The power supply station 14 includes a housing 30 installed on the floor surface 11. On the front side of the housing 30, a facing surface 31 facing the front surface 23 of the main body 20 of the traveling vehicle 12 that has moved to the power supply station 14 is formed. Above this facing surface 31, a facing convex surface 32 that is closely opposed to the main body 20 located at the power supply station 14 is formed, and below the facing surface 31, a facing concave surface 33 that faces the main body 20 and is farther from the main body 20 than the facing convex surface 32 is formed.

[0017] The power supply station 14 further includes a power transmission pad 34 installed on the facing convex surface 32 and a marker (marker group) 35 installed on the facing concave surface 33.

[0018] The power transmission pad 34 enables power transmission by a non-contact power supply method such as an electromagnetic induction method or an electric field coupling method. The power transmission pad 34 is formed in a pad shape with a built-in power transmission coil corresponding to, for example, the electromagnetic induction method. Power is transmitted from the power transmission pad 34 to the power reception pad 24 of the traveling vehicle 12 in a non-contact state where the power transmission pad 34 and the power reception pad 24 of the traveling vehicle 12 are closely opposed within a predetermined distance.

[0019] As shown in FIGS. 1 and 2, the marker 35 is, for example, an AR marker, and includes a small-sized marker 37 as the first marker and a large-sized marker 36 as the second marker. The large-sized marker 36 is arranged above the facing concave surface 33, and the small-sized marker 37 is arranged below the facing concave surface 33, and these markers 36 and 37 are arranged side by side vertically. When viewed from the front side of the housing 30, both the large-sized marker 36 and the small-sized marker 37 are formed in a rectangular shape, the centers of the large-sized marker 36 and the small-sized marker 37 are located on the same vertical axis, and are provided in the same plane. Further, the centers of the large-sized marker 36 and the small-sized marker 37 and the center of the power transmission pad 34 are located on the same vertical axis. The large-sized marker 36 is formed in a rectangle with a side length of, for example, 80 mm, and the small-sized marker 37 is formed in a rectangle with a side length of, for example, 30 mm.

[0020] Each of the markers 36 and 37 has a pattern that can be recognized by image processing. By performing image processing on the large-sized marker 36 and the small-sized marker 37 in the captured image, information on the relative attitude (relative angle in the horizontal direction) between the large-sized marker 36 and the small-sized marker 37 and the traveling vehicle 12, and information on the relative position (coordinates in the X-axis direction and the Y-axis direction in the horizontal direction) between the traveling vehicle 12 can be obtained. As shown in FIG. 4, the relative position of the traveling vehicle 12 is the XY coordinates of the traveling vehicle coordinate system with the front-rear direction of the traveling vehicle 12 as the X-axis direction and the direction intersecting the X-axis direction as the Y-axis direction with respect to the origin 12a, which is the center of the traveling vehicle 12 (the center of spin rotation (turning in place)) in the top view of the traveling vehicle 12. The relative attitude of the traveling vehicle 12 is indicated by the inclination angle (yaw angle) of the X-axis of the traveling vehicle 12 with respect to each of the markers 36 and 37. Note that the origin position in the traveling vehicle coordinate system can be arbitrarily set. Note that the relationship between the first marker and the second marker is such that the second marker has a higher recognition accuracy of the relative attitude than the first marker in the image acquired by the image acquisition unit 25 at a long distance, and the size difference between the large-sized marker 36 and the small-sized marker 37 becomes the size difference in the image captured simultaneously at a long distance, and the size difference becomes the recognition accuracy difference.

[0021] Next, the relationship between the visual field 26 of the image acquisition unit 25 of the traveling vehicle 12 and each marker 36, 37 of the power supply station 14 will be described. The image acquisition unit 25 is installed on the traveling vehicle 12 such that the lower end of the small-sized marker 37 is located near the lower end of the vertical visual field angle α within the visual field 26, and the center line 27 of the vertical visual field angle α in the visual field 26 faces upward. Further, in a state where the traveling vehicle 12 is positioned at the power supply station 14 which is the target point, the entire small-sized marker 37 is included within the visual field 26 of the image acquisition unit 25, and a part or all of the large-sized marker 36 is not included. Also, in a state where the traveling vehicle 12 is positioned at the power supply station 14 which is the target point and the main body 20 of the traveling vehicle 12 is in close proximity to and facing the opposing convex surface 32 of the stop station 14, the small-sized marker 37 in the opposing concave portion 33 is located farther than the shortest shooting distance of the image acquisition unit 25, and the small-sized marker 37 can be photographed (focused) by the image acquisition unit 25.

[0022] Next, FIG. 3 shows a block diagram of the traveling vehicle system 10. The traveling vehicle system 10 includes a traveling vehicle 12, a power supply station 14, a management terminal 40 which is a management device, and the like. The traveling vehicle 12 and the management terminal 40 can communicate with each other by wireless communication, and the power supply station 14 and the management terminal 40 can communicate with each other by wired communication or wireless communication.

[0023] The traveling vehicle 12 includes a drive unit 41, an external sensor unit 42, an internal sensor unit 43, a power reception system 44, a battery 45, and a control device 46.

[0024] The drive unit 41 includes two motors that individually rotate two drive wheels 21.

[0025] The external sensor unit 42 includes an image acquisition unit 25 which is a camera, and also includes an optical sensor, an ultrasonic sensor, etc. that detect obstacles existing in the moving direction or detect the distance to an object.

[0026] The internal sensor unit 43 acquires the moving direction and moving amount of the traveling vehicle 12 by means of an encoder that detects the rotation amount of each drive wheel 21, an acceleration sensor installed on the traveling vehicle 12, an angular velocity sensor, and the like.

[0027] The power receiving system 44 is a power receiving side device related to the charging of the battery 45, and includes a power receiving pad 24 and a power receiving unit 47. The power receiving pad 24 receives power wirelessly transmitted from the power transmission pad 34. The power receiving unit 47 converts the power received by the power receiving pad 24 into a predetermined charging power to charge the battery 45.

[0028] The battery 45 is the power source of the traveling vehicle 12 and supplies power to each electrical device provided in the traveling vehicle 12.

[0029] The control device 46 controls the traveling vehicle 12 and includes a drive control unit 48, an image processing unit 49, an odometry unit 50, and a power receiving control unit 51. The drive control unit 48 controls each motor of the drive unit 41, that is, controls the movement of the traveling vehicle 12. The image processing unit 49 performs image processing on the images of the markers 36 and 37 to recognize the relative position and relative orientation of the traveling vehicle 12 with respect to the markers 36 and 37. The odometry unit 50 calculates the moving amount of the traveling vehicle 12 based on the information of the internal sensor unit 43 and estimates the self-position and orientation of the traveling vehicle 12. The power receiving control unit 51 controls the charging of the battery 45 by the power receiving system 44.

[0030] The control device 46 is connected to the drive unit 41 and the image acquisition unit 25, and executes the output of the drive command of the drive unit 41 and the image processing of the image acquired by the image acquisition unit 25. Further, in the target movement operation of moving the traveling vehicle 12 based on the large-sized marker 36 and the small-sized marker 37 installed at the power supply station 14 which is the target point, the image acquisition unit 25 of the traveling vehicle 12 located away from the target point executes image processing on the image obtained by photographing the large-sized marker 36 and the small-sized marker 37, recognizes the relative attitude of the traveling vehicle 12 with respect to the large-sized marker 36, and recognizes the relative position of the traveling vehicle 12 with respect to the small-sized marker 37, and generates a traveling trajectory for moving to the target point from the recognized relative attitude and relative position of the traveling vehicle 12. The control device 46 drives the drive unit 41 so that the traveling vehicle 12 moves along the traveling trajectory, and when the traveling vehicle 12 approaches the target point, executes image processing on the photographed image of the small-sized marker 37, and recognizes the relative position and relative attitude of the traveling vehicle 12 based on the small-sized marker 37. At this time, during the movement of the traveling vehicle 12 to the target point, the marker to be recognized is changed so that the recognition of the relative attitude of the traveling vehicle 12 is recognized based on the small-sized marker 37 instead of the large-sized marker 36.

[0031] Also, the power supply station 14 includes a power transmission system 53 and a marker 35. The power transmission system 53 is power transmission side equipment related to the charging of the battery 45, and includes a power transmission pad 34 and a power transmission unit 54. The power transmission pad 34 transmits power to the power reception pad 24 in a non-contact manner. The power transmission unit 54 converts power and causes it to be transmitted from the power transmission pad 34. The marker 35 includes a large-sized marker 36 and a small-sized marker 37.

[0032] In addition, the management terminal 40 includes a work management unit 56, a map management unit 57, a traveling vehicle management unit 58, and a power supply station management unit 59. The work management unit 56 manages the work information and work progress information of the traveling vehicle 12, the work assignment to the traveling vehicle 12, etc. The map management unit 57 manages the arrangement of each device on the floor in the facility as coordinate information. The traveling vehicle management unit 58 manages the working status of the traveling vehicle 12 and the state such as the remaining power stored in the battery 45, and notifies the map coordinates of the target point to be moved in the work instruction for the traveling vehicle 12. The power supply station management unit 59 manages the operating status of the power supply station 14.

[0033] Next, the operation of the traveling vehicle system 10 will be described.

[0034] The management terminal 40 assigns work to the traveling vehicle 12 that is the work target, and the traveling vehicle 12 to which the work is assigned executes work such as transporting the transported item.

[0035] The management terminal 40 monitors the remaining amount of power stored in the battery 45 of each traveling vehicle 12. When a traveling vehicle 12 whose remaining power of the battery 45 falls below the reference value is detected, that traveling vehicle 12 is removed from the new work assignment target as a charging required target, and an available power supply station 14 is reserved.

[0036] The management terminal 40 instructs the traveling vehicle 12 that requires charging to move to the reserved power supply station 14.

[0037] The traveling vehicle 12 to be charged, which has received an instruction from the management terminal 40, executes a target movement operation to the power supply station 14 that is the target location. In this target movement operation, during the movement to the power supply station 14, the vehicle temporarily stops at a position slightly away from the power supply station 14 (for example, about 1 m in front) as a waypoint P1 (see Fig. 4(a)), searches for the markers 36, 37 of the power supply station 14, and then approaches and moves towards the markers 36, 37 of the power supply station 14. Note that the waypoint P1 is the starting position where the positioning operation, which is the final process of the target movement operation for the autonomous movement of the traveling vehicle 12 to the target position, starts. Whether to temporarily stop at this starting position or continue the operation without a temporary stop is arbitrary.

[0038] As shown in Fig. 4(a), the traveling vehicle 12 temporarily stops at the waypoint P1 on the way to the power supply station 14, processes the captured image taken by the image acquisition unit 25, and searches for the markers 36, 37. After confirming the markers 36, 37, the XY coordinates of the small-sized marker 37 with respect to the origin 12a of the traveling vehicle 12 are acquired from the small-sized marker 37 (the large-sized marker 36 may also be used).

[0039] As shown in Fig. 4(b), with the front surface 23 of the traveling vehicle 12 facing the markers 36, 37 of the power supply station 14, the traveling vehicle 12 spins and rotates at the waypoint P1 so that the center in the left-right direction of the captured image taken by the image acquisition unit 25 (that is, the X-axis direction extending forward from the origin 12a of the traveling vehicle 12) coincides with the center in the left-right direction of the markers 36, 37.

[0040] The captured image taken by the image acquisition unit 25 of the traveling vehicle 12 is processed to recognize the relative posture of the traveling vehicle 12 with respect to the large-sized marker 36. This relative posture is the angle θ formed by the perpendicular line 61 perpendicular to the center of the surface of the large-sized marker 36 and the X-axis direction extending forward of the traveling vehicle 12. Furthermore, the captured image taken by the image acquisition unit 25 of the traveling vehicle 12 is processed to recognize the relative position of the traveling vehicle 12 with respect to the small-sized marker 37. This relative position is the XY coordinates of the traveling vehicle 12 with respect to the small-sized marker 37.

[0041] At this time, since the traveling vehicle 12 located at the passing point P1 is at a position slightly away from the power feeding station 14, it is possible to recognize the relative position from the small-sized marker 37 in the captured image captured by the image acquisition unit 25 of the traveling vehicle 12. However, regarding the relative attitude (angle θ), since it is recognized from the inclination of the small-sized marker 37 and the like, the small-sized marker 37 in the captured image may be too small and the recognition accuracy may be poor. On the other hand, from the large-sized marker 36 recognized from the captured image captured by the image acquisition unit 25 of the traveling vehicle 12, it is larger than the small-sized marker 37 in the captured image, and the relative attitude (angle θ) can be recognized with high accuracy from the inclination of the large-sized marker 36 and the like.

[0042] The traveling vehicle 12 that has recognized the relative attitude and relative position with respect to the markers 36 and 37 of the power feeding station 14 generates a traveling trajectory in which it turns around to the front of the markers 36 and 37 of the power feeding station 14 from the passing point P1 and moves closer, and moves along the traveling trajectory.

[0043] The traveling trajectory includes a first traveling trajectory that moves the origin 12a of the traveling vehicle 12 to an intermediate point P2 set on a vertical line 61 that is a line perpendicular to the marker surface of the markers 36 and 37 and extends from the center of the marker surface, and a second traveling trajectory that the traveling vehicle 12 moves from the intermediate point P2 toward the markers 36 and 37 of the power feeding station 14.

[0044] The intermediate point P2 set on the vertical line 61 is the point where the virtual line extending from the origin 12a of the traveling vehicle 12 intersects the vertical line 61 at a right angle. Alternatively, it may be a point closer to the markers 36 and 37 of the power feeding station 14 than the point where the virtual line extending from the origin 12a of the traveling vehicle 12 intersects the vertical line 61 at a right angle, and it is sufficient that the origin 12a of the traveling vehicle 12 can move from the relay point P1 to the intermediate point P2.

[0045] Figures 4(c) to 4(h) show the target movement operation of the traveling vehicle 12 along the traveling trajectory to the power supply station 14 which is the target point. As shown in Figure 4(c), after the traveling vehicle 12 spins and rotates towards the intermediate point P2, it moves forward. As shown in Figure 4(d), when the origin 12a of the traveling vehicle 12 reaches the intermediate point P2 on the vertical line 61, the traveling vehicle 12 temporarily stops.

[0046] As shown in Figure 4(e), the traveling vehicle 12 spins and rotates so that the front surface 23 of the traveling vehicle 12 faces the markers 36 and 37 of the power supply station 14. By facing each of the markers 36 and 37 of the power supply station 14, the captured image captured by the image acquisition unit 25 of the traveling vehicle 12 is image - processed to recognize the relative attitude from the large - size marker 36 and the relative position from the small - size marker 37.

[0047] At this time, since the traveling vehicle 12 is at a position away from the power supply station 14, both the large - size marker 36 and the small - size marker 37 are included in the field of view 26 of the image acquisition unit 25. The captured image captured by the image acquisition unit 25 at this time is shown in Figure 5(a). Both the large - size marker 36 and the small - size marker 37 are included within the frame of the captured image corresponding to the field of view 26 of the image acquisition unit 25, and the large - size marker 36 and the small - size marker 37 are recognized from this captured image.

[0048] As shown in Figures 4(f) and 1(a), the traveling vehicle 12 facing the markers 36 and 37 of the power supply station 14 moves forward towards the markers 36 and 37 of the power supply station 14. At this time, the traveling vehicle 12 image - processes the captured image captured by the image acquisition unit 25 and moves forward while confirming the relative attitude recognized from the large - size marker 36 and the relative position recognized from the small - size marker 37. If there is a deviation in the relative attitude with respect to the large - size marker 36 or the relative position with respect to the small - size marker 37, the rotation of the drive wheels 21 on both sides is individually controlled to correct the traveling direction of the traveling vehicle 12 with respect to the small - size marker 37 while moving forward.

[0049] As shown in FIGS. 4(g) and 1(c), when the traveling vehicle 12 approaches the markers 36 and 37 of the power supply station 14, the entire small-sized marker 37 is included in the field of view 26 of the image acquisition unit 25, but a part of the upper side of the large-sized marker 36 is not included. The captured image taken by the image acquisition unit 25 at this time is shown in FIG. 5(b). The entire small-sized marker 37 is included within the frame of the captured image corresponding to the field of view 26 of the image acquisition unit 25, but a part of the upper side of the large-sized marker 36 is not included. From this captured image, the large-sized marker 36 is not recognized, and only the small-sized marker 37 is recognized.

[0050] Therefore, the traveling vehicle 12 recognized the relative attitude with respect to the large-sized marker 36 until just before and approached and moved toward the markers 36 and 37 of the power supply station 14. However, after the large-sized marker 36 is no longer recognized, it recognizes the relative attitude from the small-sized marker 37 and approaches and moves toward the markers 36 and 37 of the power supply station 14.

[0051] At this time, since the traveling vehicle 12 approaches the markers 36 and 37 of the power supply station 14 and the small-sized marker 37 in the captured image taken by the image acquisition unit 25 is large, the relative attitude can be recognized with high accuracy even from the small-sized marker 37. Incidentally, when the information on the relative attitude is simultaneously acquired from both the markers 36 and 37 during this straight travel, and when the large-sized marker 36 protrudes from the field of view of the image acquisition unit 25 and cannot be recognized, by overwriting the information on the relative attitude acquired from the large-sized marker 36 with the information on the relative attitude acquired from the small-sized marker 37 as correct, even when the recognition target switches between the markers 36 and 37, it includes changing the recognized markers 36 and 37.

[0052] After that, when the traveling vehicle 12 determines that it has reached the power supply station 14, which is the target point, from the relative position with respect to the small marker 37, it stops moving. If the relative position and relative attitude of the traveling vehicle 12 with respect to the small marker 37 are normal, it is determined that the power receiving pad 24 of the traveling vehicle 12 and the power transmitting pad 34 of the power supply station 14 are facing each other at a predetermined interval, and the power transmitting pad 34 of the power supply station 14 transmits power to the power receiving pad 24 of the traveling vehicle 12, and starts charging the battery 45 of the traveling vehicle 12.

[0053] Also, if there is an abnormality in the relative position and relative attitude of the traveling vehicle 12 with respect to the small marker 37, the traveling vehicle 12 once retreats to a predetermined retreat position and then executes the target movement operation toward the power supply station 14, which is the target point, again.

[0054] In this way, in the target movement operation in which the traveling vehicle 12 moves based on the large marker 36 and the small marker 37 installed at the power supply station 14, which is the target point, while the traveling vehicle 12 is located away from the power supply station 14, the image acquisition unit 25 of the traveling vehicle 12 performs image processing on the images obtained by photographing both the large marker 36 and the small marker 37, recognizes the relative attitude of the traveling vehicle 12 with respect to the large marker 36, and recognizes the relative position of the traveling vehicle 12 with respect to the small marker 37. A traveling trajectory for moving to the power supply station 14 is generated from the recognized relative attitude and relative position of the traveling vehicle 12, and the traveling vehicle 12 moves along the traveling trajectory. Also, while the traveling vehicle 12 is approaching the power supply station 14, image processing is performed on the photographed image of the small marker 37 to recognize the relative position and relative attitude of the traveling vehicle 12 based on the small marker 37. Therefore, both in the state where the traveling vehicle 12 is located away from the power supply station 14 and in the state where the traveling vehicle 12 is approaching the power supply station 14, the relative attitude and relative position of the traveling vehicle 12 with respect to the markers 36 and 37 of the power supply station 14 can be recognized with high accuracy, the accuracy of the autonomous movement of the traveling vehicle 12 to the power supply station 14 is high, and the accuracy of the stop position of the traveling vehicle 12 at the power supply station 14 can be improved.

[0055] The target movement operation in which the traveling vehicle 12 moves based on the large-sized marker 36 and the small-sized marker 37 installed at the power supply station 14 which is the target location starts from the via point P1 which is at a position away from the power supply station 14 and offset from the front of the power supply station 14. Therefore, by recognizing the relative pose from the large-sized marker 36 with high-accuracy angle information, the accuracy of the traveling vehicle 12 turning in to the position facing the markers 36, 37 of the power supply station 14 can be improved.

[0056] During the movement of the traveling vehicle 12 towards the power supply station 14, in order to change the marker to be recognized so that the relative pose of the traveling vehicle 12 is recognized based on the small-sized marker 37 from the large-sized marker 36, when the traveling vehicle 12 approaches the markers 36, 37 of the power supply station 14, even if part or all of the large-sized marker 36 is not included in the field of view 26 of the image acquisition unit 25, the relative pose and relative position can be recognized with high accuracy from the small-sized marker 37.

[0057] Also, since the image acquisition unit 25 of the traveling vehicle 12 is installed on the traveling vehicle 12 such that the center line 27 of the vertical field of view angle α in the field of view 26 faces upward so that the lower end of the small-sized marker 37 is located near the lower end of the range of the vertical field of view angle α in the field of view 26, the small-sized marker 37 always enters the field of view 26 regardless of the distance between the traveling vehicle 12 and the small-sized marker 37, and the small-sized marker 37 does not go out of the field of view 26 even when approaching.

[0058] Therefore, when the traveling vehicle 12 is located away from the power supply station 14, the entire large-sized marker 36 and the entire small-sized marker 37 are included within the visual field 26 of the image acquisition unit 25. Based on the large-sized marker 36, the traveling vehicle 12 can be moved toward the power supply station 14, which is the target point. Also, when the traveling vehicle 12 is located at the power supply station 14, a part or all of the large-sized marker 36 is not included within the visual field 26 of the image acquisition unit 25. However, since the entire small-sized marker 37 is included, after the traveling vehicle 12 approaches the power supply station 14, the traveling vehicle 12 can be positioned at the power supply station 14 based on the small-sized marker 37. The accuracy of the autonomous movement of the traveling vehicle 12 toward the power supply station 14 is high, and the accuracy of the stop position of the traveling vehicle 12 at the power supply station 14 can be improved.

[0059] Both the large-sized marker 36 and the small-sized marker 37 are formed in a rectangular shape, and the centers of the large-sized marker 36 and the small-sized marker 37 are located on the same vertical axis and are provided in the same plane. Therefore, the recognition target can be smoothly changed from the large-sized marker 36 to the small-sized marker 37 during the movement of the traveling vehicle 12 toward the power supply station 14.

[0060] Also, the power supply station 14, which is the target point, has an opposing convex surface 32 that is closely opposed to the main body 20 located at the power supply station 14, and an opposing concave surface 33 that faces the main body 20 and is farther from the main body 20 than the opposing convex surface 32. Since the marker 35 is installed on the opposing concave surface 33, when the traveling vehicle 12 is located at the power supply station 14 and is in a state of being closely opposed to the opposing convex surface 32, the marker 35 on the opposing concave portion 33 is located farther than the shortest shooting distance of the image acquisition unit 25. Therefore, the marker 35 can be photographed and recognized until the traveling vehicle 12 reaches the power supply station 14. The accuracy of the autonomous movement of the traveling vehicle 12 toward the power supply station 14 is high, and the accuracy of the stop position of the traveling vehicle 12 at the power supply station 14 can be improved.

[0061] Also in this case, by having the large-sized marker 36 and the small-sized marker 37 as the marker 35, when the traveling vehicle 12 is located away from the power feeding station 14, the traveling vehicle 12 can be moved toward the power feeding station 14 based on the large-sized marker 36 included in the visual field 26 of the image acquisition unit 25. When the traveling vehicle 12 approaches the markers 36 and 37 of the power feeding station 14, even if part or all of the large-sized marker 36 is not included in the visual field 26 of the image acquisition unit 25, the traveling vehicle 12 can be positioned at the power feeding station 14 based on the small-sized marker 37. The accuracy of the autonomous movement of the traveling vehicle 12 to the power feeding station 14 is high, and the accuracy of the stop position of the traveling vehicle 12 at the power feeding station 14 can be improved.

[0062] Next, a second embodiment is shown in FIG. 6.

[0063] A power receiving pad 24 is installed below the front surface 23 (or the rear surface in the reverse direction) in the forward direction of the main body 20 of the traveling vehicle 12, and an image acquisition unit 25 is installed above the front surface 23 of the main body 20.

[0064] The image acquisition unit 25 is installed on the main body 20 such that the upper end portion (upper side) in the range of the vertical viewing angle α in the visual field 26 is located in a substantially horizontal direction and the center line 27 of the vertical viewing angle α in the visual field 26 faces downward.

[0065] Further, in the power feeding station 14, a facing convex surface 32 that faces and is close to the main body 20 located at the power feeding station 14 is formed below the facing surface 31 on the front side of the housing 30. Also, a facing concave surface 33 that faces the main body 20 and is farther from the main body 20 than the facing convex surface 32 is formed above the facing surface 31. A power transmission pad 34 is installed on the facing convex surface 32, and markers 36 and 37 are installed on the facing concave surface 33. The large-sized marker 36 is arranged on the lower side of the facing concave surface 33, and the small-sized marker 37 is arranged on the upper side of the facing concave surface 33, and these markers 36 and 37 are arranged side by side from bottom to top.

[0066] Regarding the relationship between the visual field 26 of the image acquisition unit 25 of the traveling vehicle 12 and each marker 36, 37 of the power supply station 14 in this case, the image acquisition unit 25 has a relationship such that the upper end of the small-sized marker 37 is located near the upper end of the vertical visual field angle α within the visual field 26, and the center line 27 of the vertical visual field angle α in the visual field 26 faces downward. Further, in a state where the traveling vehicle 12 is positioned at the power supply station 14 which is the target point, the entire small-sized marker 37 is included within the visual field 26 of the image acquisition unit 25, and a part or all of the large-sized marker 36 is not included. Also, in a state where the traveling vehicle 12 is positioned at the power supply station 14 which is the target point and the main body 20 of the traveling vehicle 12 is in close proximity and facing the opposing convex surface 32 of the power supply station 14, the small-sized marker 37 of the opposing concave portion 33 is located farther than the shortest shooting distance of the image acquisition unit 25, and has a relationship that enables the small-sized marker 37 to be photographed by the image acquisition unit 25.

[0067] Also in this second embodiment, similar to the first embodiment, the accuracy of the autonomous movement of the traveling vehicle 12 to the power supply station 14 is high, and the accuracy of the stop position of the traveling vehicle 12 at the power supply station 14 can be improved.

[0068] Note that the stop station 13 is not limited to the power supply station 14, and may be a station at the source that receives the conveyed object mounted on the traveling vehicle 12 or connects a towing object to the traveling vehicle 12, or a station at the destination that takes out the conveyed object from the traveling vehicle 12 or removes the towing object from the traveling vehicle 12, etc.

[0069] Also, for the first marker and the second marker, in addition to the size relationship, a recognition accuracy relationship can be established, and two or more markers can be combined to form the first marker and the second marker.

[0070] As described above, the embodiments of the present invention and their modifications have been explained, but various combinations of configurations, partial omissions, replacements, and changes are also possible.

Explanation of Reference Numerals

[0071] 10 Traveling Vehicle System 12 Traveling vehicle 13 Stop station 20 Main body 25 Image acquisition unit 26 Field of view 27 Center line 32 Opposing convex surface 33 Opposing concave surface 35 Marker 36 Large-sized marker which is the second marker 37 Small-sized marker which is the first marker 41 Driving unit 46 Control device

Claims

1. A traveling vehicle that autonomously moves to a target location, comprising: a main body; a drive unit installed on the main body for moving the main body; an image acquisition unit installed on the main body for photographing the outside of the main body; a control device connected to the drive unit and the image acquisition unit, for outputting a drive command for the drive unit and performing image processing on the image acquired by the image acquisition unit; in a target movement operation of moving the traveling vehicle based on markers including at least a first marker arranged in parallel corresponding to the target location and a second marker having a higher recognition accuracy of relative pose than the first marker in an image acquired by the image acquisition unit at a position away from the target location, when the traveling vehicle is at a position away from the target location, the traveling vehicle performs image processing on an image of the second marker and / or the first marker included in the image photographed by the image acquisition unit of the traveling vehicle, to recognize the relative pose of the traveling vehicle with respect to the second marker, and to recognize the relative position of the traveling vehicle with respect to the second marker or the first marker; generates a traveling trajectory for moving to the target location from the recognized relative pose and relative position of the traveling vehicle, and drives the drive unit so that the traveling vehicle moves along the traveling trajectory; when the traveling vehicle is at a position close to the target location, performs image processing on a photographed image of the first marker to recognize the relative position and relative pose of the traveling vehicle based on the first marker A traveling vehicle characterized by the above.

2. The control device changes a marker to be recognized so that, during the movement of the traveling vehicle to the target location, the recognition of the relative pose of the traveling vehicle is based on the first marker instead of the second marker. The traveling vehicle according to claim 1, characterized by the above.

3. The first marker is a small-sized marker, and the second marker is a large-sized marker having a size larger than that of the first marker, the image acquisition unit can simultaneously photograph the entire small-sized marker and the entire large-sized marker when the main body is at a position away from the target location, and can photograph the entire small-sized marker and a part of the large-sized marker or only the entire small-sized marker when the main body is at a position close to the target location. The traveling vehicle according to claim 2, characterized by the above.

4. A traveling vehicle system for stopping a traveling vehicle that autonomously moves to a target location at the target location, A traveling vehicle having a main body portion, a driving portion installed on the main body portion for moving the main body portion, an image acquisition portion installed on the main body portion having a predetermined field of view for photographing the outside of the main body portion, and a control device connected to the driving portion and the image acquisition portion for outputting a driving command of the driving portion and performing image processing on the image acquired by the image acquisition portion. A marker including a large-sized marker installed vertically above and a small-sized marker installed vertically below at a position corresponding to the target point. The image acquisition portion is installed on the main body portion such that the lower end portion of the small-sized marker is located near the lower end portion of the vertical field of view angle in the field of view and the center line of the vertical field of view angle in the field of view faces upward. With the traveling vehicle away from the target point, the entire small-sized and large-sized markers are included in the field of view of the image acquisition portion. When the traveling vehicle is positioned at the target point, the entire small-sized marker is included in the field of view of the image acquisition portion, and a part or all of the large-sized marker is not included. A traveling vehicle system characterized by the above.

5. A traveling vehicle system for stopping a traveling vehicle that autonomously moves to a target point at the target point, comprising: A traveling vehicle having a main body portion, a driving portion installed on the main body portion for moving the main body portion, an image acquisition portion installed on the main body portion having a predetermined field of view for photographing the outside of the main body portion, and a control device connected to the driving portion and the image acquisition portion for outputting a driving command of the driving portion and performing image processing on the image acquired by the image acquisition portion. A marker including a small-sized marker installed vertically above and a large-sized marker installed vertically below at a position corresponding to the target point. The image acquisition portion is installed on the main body portion such that the upper end portion of the small-sized marker is located near the upper end portion of the vertical field of view angle in the field of view and the center line of the vertical field of view angle in the field of view faces downward. With the traveling vehicle away from the target point, the entire small-sized and large-sized markers are included in the field of view of the image acquisition portion. When the traveling vehicle is positioned at the target point, the entire small-sized marker is included in the field of view of the image acquisition portion, and a part or all of the large-sized marker is not included. A traveling vehicle system characterized by the above.

6. Both the large-sized marker and the small-sized marker are formed in a rectangular shape, and the centers of the large-sized marker and the small-sized marker are located on the same vertical axis and are provided in the same plane. The traveling vehicle system according to claim 4 or 5, characterized in that.

7. A traveling vehicle system for stopping a traveling vehicle that autonomously moves to a target point at the target point, a main body portion, a drive portion installed in the main body portion for moving the main body portion, an image acquisition portion installed in the main body portion having a predetermined field of view for photographing the outside of the main body portion, and connected to the drive portion and the image acquisition portion, A traveling vehicle having a control device that executes output of a drive command of the drive portion and image processing of an image acquired by the image acquisition portion, a stop station installed at the target point and having an opposing convex surface formed at a position that is opposed to and close to the main body portion located at the target point, and an opposing concave surface formed at a position that is opposed to the main body portion and farther from the main body portion than the opposing convex surface, a marker installed on the opposing concave surface, The marker is located farther than the shortest shooting distance of the image acquisition unit in a state where the main body portion is opposed to the opposing convex surface of the stop station in a close proximity. The traveling vehicle system characterized by that.

8. The marker includes a large-sized marker and a small-sized marker arranged side by side. In a state where the main body portion is opposed to the opposing convex surface of the stop station in a close proximity, the entire small-sized marker is included within the field of view of the image acquisition unit, and a part or all of the large-sized marker is not included. The traveling vehicle system according to claim 7, characterized in that.

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