Conveying system, station for transport vehicles, and method for entering the station

Abstract

To enable even an autonomously traveling carrier vehicle to accurately approach and stop in a parking space of a station.SOLUTION: A station 1 comprises: left and right legs 100 and 102 that define an entrance 120 to a parking space Ps; left and right lateral walls 130 and 132 that define a left-right boundary of the parking space Ps; a first approach reflection plate 140 disposed in one 100 of the left and right legs 100 and 102 to reflect detection light; a second approach reflection plate 141 disposed in the other 102 of the left and right legs 100 and 102 to reflect the detection light; and a stop reflection light 145 disposed in one 130 of the left and right lateral walls 130 and 132. The first and second approach reflection plate 140 and 141 are arranged to face an AMR 2 entering the parking space Ps, and the stop reflection light 145 is disposed to face the other lateral wall 132.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a transport system, a station for a transport vehicle, and a station entry method.

Background Art

[0002] In factories that process materials such as sheet metal, continuous processing may be performed using different types of processing machines. For example, a material cut out by a laser cutting machine is bent into a desired shape by a press brake. In the factory, a station for placing a pallet loaded with the material is provided for each processing machine, and the transport of the material is automatically performed as the transport vehicle travels back and forth between the stations. The transport vehicle is an autonomous mobile robot referred to as an AMR (Autonomous Mobile Robot), and has a function of estimating its own position with a sensor to travel autonomously.

[0003] For example, Patent Document 1 discloses a position estimation system capable of estimating the self-position of a mobile body with high accuracy regardless of the surrounding environment of the mobile body.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The parking space for the transport vehicle at the station is limited. Therefore, there is a demand for a technology that enables even a transport vehicle that travels autonomously to accurately enter and stop in the parking space of the station.

Means for Solving the Problems

[0006] A transport system according to one aspect of the present invention includes a transport vehicle that autonomously travels and transports transported objects based on the detection results of a sensor that detects surrounding objects by receiving reflected light of detection light irradiated into the surroundings, and a station that forms a parking space for the transport vehicle to enter and stop, and has a support above the parking space on which the transported object can be placed, wherein the station is arranged spaced apart to the left and right as viewed from the transport vehicle entering the parking space and defines an entrance to the parking space, left and right lateral guides provided along the direction in which the transport vehicle enters the parking space and define the left and right sides of the parking space, a first reflector arranged on one of the left and right structures that reflects detection light, a second reflector arranged on the other of the left and right structures that reflects detection light, and a third reflector arranged on one of the left and right lateral guides that reflects detection light, wherein the first and second reflectors are arranged facing the transport vehicle entering the parking space, and the third reflector is arranged facing the other lateral guide.

[0007] According to one aspect of the present invention, the first and second reflectors, positioned opposite the transport vehicle as it approaches the entrance to the parking space, allow the transport vehicle to properly recognize the entrance. Furthermore, since the third reflector is positioned on one lateral guide facing the other lateral guide, it is difficult for the transport vehicle traveling towards the entrance to detect it. This prevents the transport vehicle from mistakenly recognizing the third reflector as the first and second reflectors when entering the entrance. As a result, the transport vehicle can be driven accurately towards the entrance.

[0008] In addition, the presence of a third reflector within the station allows for precise stopping of transport vehicles at designated locations within the parking space. [Effects of the Invention]

[0009] According to one aspect of the present invention, a transport vehicle can autonomously drive and precisely enter and stop at a station. [Brief explanation of the drawing]

[0010] [Figure 1] Figure 1 is an explanatory diagram showing the system configuration of the transport system according to this embodiment. [Figure 2] Figure 2 illustrates the environment in which the transport system is applied. [Figure 3] Figure 3 is a perspective view showing the configuration of the AMR. [Figure 4] Figure 4 is a block diagram showing the configuration of the AMR. [Figure 5] Figure 5 is a perspective view showing the structure of the station. [Figure 6] Figure 6 is a flowchart showing the AMR's processing during station entry. [Figure 7] Figure 7 is a flowchart showing the AMR's processing during station entry. [Figure 8] Figure 8 shows the movement of the AMR until it reaches the scanning position. [Figure 9] Figure 9 shows the AMR's movement as it enters the parking space. [Figure 10] Figure 10 shows the AMR's movement until it comes to a stop at the designated stopping position. [Figure 11] Figure 11 illustrates another example of a lateral guide for a station. [Figure 12] Figure 12 illustrates another example of a lateral guide for a station. [Modes for carrying out the invention]

[0011] The transport system, transport vehicle station, and station access method according to this embodiment will be described below with reference to the drawings.

[0012] Figure 1 is an explanatory diagram showing the system configuration of the transport system according to this embodiment. The transport system according to this embodiment includes an AMR (Autonomous Mobile Robot) 2 that autonomously travels based on the detection results of sensors 23a and 23b that detect surrounding objects by receiving reflected light from detection light irradiated into the surroundings, and transports a pallet 5 (not shown), and a station 1 that forms a stopping space Ps for the AMR 2 to enter and stop, and is provided with a support part 110 above the stopping space Ps on which the pallet 5 can be placed. Station 1 is positioned spaced apart to the left and right from the perspective of the AMR2 entering the parking space Ps and includes left and right legs 100, 102 that define an entrance 120 to the parking space Ps, left and right side walls 130, 132 that are provided along the direction of entry in which the AMR2 enters the parking space Ps and define the left and right boundaries of the parking space Ps, a first entry reflector 140 positioned on one of the left and right legs 100, 102 that reflects detection light, a second entry reflector 141 positioned on the other leg 102 of the left and right legs 100, 102 that reflects detection light, and a stopping reflector 145 positioned on one of the left and right side walls 130, 132 that reflects detection light. The first entry reflector 140 and the second entry reflector 141 are positioned to face the AMR2 entering the parking space Ps, and the stopping reflector 145 is positioned to face the other side wall 132.

[0013] In this specification, the direction of AMR2 is defined with respect to the direction of travel FW of AMR2. Specifically, the direction of travel FW of AMR2, the direction opposite to the direction of travel FW, the left side of the direction of travel FW, and the right side of the direction of travel FW are referred to as the forward direction, backward direction, left direction, and right direction of AMR2, respectively. Furthermore, the direction of Station 1 is defined as the direction as seen from AMR2 when it is facing upright toward the entrance 120 of Station 1. Specifically, the side closer to AMR2 (near side), the side farther from AMR2 (far side), the left side of AMR2, and the right side of AMR2 are referred to as the forward direction, backward direction, left direction, and right direction of Station 1, respectively.

[0014] Hereinafter, details of the conveyance system according to the present embodiment will be described. FIG. 2 is a diagram for explaining an environment to which the conveyance system is applied. The environment to which the conveyance system according to the present embodiment is applied is, for example, a factory. The factory is provided with a first processing machine 7 such as a laser cutting machine that performs cutting processing on a material, and a second processing machine 8 such as a press brake that performs bending processing on a material. In this factory, a step of cutting a material with the first processing machine 7 to manufacture a part for a predetermined product, and a step of bending the part for the product with the second processing machine 8 to manufacture a predetermined product are performed.

[0015] The conveyance system is a system that automatically conveys materials. The conveyance of materials by the conveyance system includes carrying a material (material before processing) into the first processing machine 7, carrying out the material (part for product) processed by the first processing machine 7 and carrying it into the second processing machine 8, carrying out the material (product) processed by the second processing machine 8, and the like.

[0016] The conveyance system is composed of two stations 1 and an AMR 2. The two stations 1 are provided corresponding to the first and second processing machines 7 and 8. The configuration of each individual station 1 is identical. The AMR 2 carries a pallet (an example of a conveyed object) 5 on which a material is placed to each station 1, thereby carrying the material into and out of each of the processing machines 7 and 8.

[0017] In the example shown in FIG. 2, the factory is provided with two processing machines 7, 8 and two stations 1, but the present embodiment is not limited thereto. Further, although one AMR 2 that conveys the pallet 5 is illustrated, the present embodiment is not limited thereto.

[0018] First, the AMR 2 will be described with reference to FIG. 1, FIG. 3 and FIG. 4. FIG. 3 is a perspective view showing the configuration of the AMR. FIG. 4 is a block diagram showing the configuration of the AMR.

[0019] AMR2 is a transport vehicle that autonomously moves and transports pallet 5 based on detection results of surrounding objects. AMR2 is equipped with a battery (not shown) and runs on power supplied from the battery.

[0020] As shown in Figure 4, the AMR2 comprises a control unit 21, a wireless communication unit 22, a pair of sensors 23a and 23b, a pair of drive motors 24a and 24b, a pair of wheels 25a and 25b, a lifter drive unit 26, a lifter 27, and a map storage unit 29.

[0021] These elements that make up the AMR2 are housed within the vehicle body 200 shown in Figure 3. A pallet 5 (not shown) can be mounted on the top plate 210 that forms the ceiling portion of the vehicle body 200. In other words, the AMR2 transports the pallet 5 by driving with the pallet 5 mounted on the top plate 210.

[0022] As shown in Figure 4, the control unit 21 is composed of a computer, such as a microcomputer, and controls the operation of the AMR2. The wireless communication unit 22 communicates with external devices such as the first and second processing machines 7 and 8, or a management device that manages factory production. The wireless communication unit 22 can be composed of a communication circuit and a wireless transceiver.

[0023] Since the pair of sensors 23a and 23b have the same configuration, the configuration of one of the sensors, 23a, will be described. Sensor 23a detects surrounding objects by receiving reflected light from detection light irradiated into the surroundings. For example, sensor 23a is a LiDAR (Light Detection and Ranging) and acquires point cloud data indicating the distance to objects present around the AMR2. Sensors 23a and 23b may also be stereo cameras or TOF (Time Of Flight) sensors.

[0024] As shown in Figure 1, of the pair of sensors 23a and 23b, one sensor 23a is positioned at the left end of the front of the AMR2's vehicle body 200, and the other sensor 23b is positioned at the right end of the rear of the AMR2's vehicle body 200. One sensor 23a is mounted slightly to the left of the front of the AMR2. One sensor 23a has a detection range θb1 that is sufficient to detect objects in front of and to the left of the AMR2. The other sensor 23b is mounted slightly to the right of the rear of the AMR2. The other sensor 23b has a detection range θb2 that is sufficient to detect objects in the rear and to the right of the AMR2. This arrangement of the pair of sensors 23a and 23b allows for detection of the entire area around the AMR2 even with a small number of sensors.

[0025] As shown in Figure 4, one drive motor 24a rotates one wheel 25a, and the other drive motor 24b rotates the other wheel 25b. Each drive motor 24a and 24b can be controlled independently by the control unit 21.

[0026] As shown in Figure 1, a pair of wheels 25a and 25b are positioned on the vehicle body 200, spaced apart to the left and right. The orientation of each wheel 25a and 25b is fixed relative to the vehicle body 200. As shown in Figure 3, the direction of travel FW of the AMR2 is determined according to the rotation direction R1 of the pair of wheels 25a and 25b. If the pair of wheels 25a and 25b rotate in the opposite direction to the rotation direction R1 shown in Figure 3, the direction of travel FW of the AMR2 will also be reversed.

[0027] As shown in Figure 4, the lifter drive unit 26 is a drive unit that drives the lifter 27 and is composed of an actuator such as a motor. The lifter 27 is a mechanism that raises and lowers the top plate 210. When the lifter 27 raises the top plate 210 with the pallet 5 placed on the top plate 210 of the AMR200, the pallet 5 is lifted upward.

[0028] The map storage unit 29 stores map data of the environment in which the AMR200 operates, i.e., the factory. This map data is composed of point cloud data obtained when the AMR200 previously drove around the factory. The map storage unit 29 is composed of, for example, non-volatile memory.

[0029] In this configuration of AMR2, sensors 23a and 23b emit detection light around the AMR2 and detect surrounding objects by receiving the reflected light. The detection of surrounding objects corresponds to the detection of point cloud data indicating the distance to objects around the AMR2. Based on the detection results of sensors 23a and 23b, the AMR2 autonomously moves and transports the pallet 5.

[0030] In this autonomous driving operation, the control unit 21 estimates the position (self-position) of the AMR2 by matching the map data read from the map storage unit 29 with the detection results of sensors 23a and 23b. Based on the estimated self-position, the control unit 21 controls the drive motors 24a and 24b to change the AMR2's course, thereby enabling the AMR2 to travel to the target location within the factory. Furthermore, if the control unit 21 recognizes an object (obstacle) that does not exist in the map data based on the detection results of sensors 23a and 23b, it can avoid that object by controlling the drive motors 24a and 24b.

[0031] Next, Station 1 will be described with reference to Figures 1 and 5. Figure 5 is a perspective view showing the structure of the station. Station 1 consists of four legs 100, 101, 102, and 103 and a support part 110.

[0032] As shown in Figure 5, the four legs 100, 101, 102, and 103 are positioned at the corners of the support section 110, which has a roughly rectangular shape. The area enclosed by the four legs 100, 101, 102, and 103 corresponds to the parking space Ps for the AMR2 to enter and stop.

[0033] The support section 110 is supported by four legs 100, 101, 102, and 103 and is positioned above the parking space Ps. The support section 110 is a frame having a substantially rectangular shape and is configured to accommodate the pallet 5. The front side of the support section 110 is open to allow the AMR 2 to enter.

[0034] As shown in Figure 1, the pair of front legs 100 and 102 are positioned spaced apart to the left and right when viewed from the perspective of the AMR2 entering the parking space Ps. The left and right legs 100 and 102 correspond to the left and right structures that define the entrance 120 to the parking space Ps.

[0035] As shown in Figure 5, a left lateral wall (an example of a left lateral guide) 130 is provided between the pair of legs 100 and 101 on the left side, defining the left boundary of the parking space Ps. The left lateral wall (hereinafter referred to as the "lateral wall") 130 is a plate-shaped member that stands upright in the vertical direction and is provided along the front-rear direction, which is the direction in which the AMR2 enters the parking space Ps. The left wall 130 is also formed flush with the surface along the front-rear direction.

[0036] Between the pair of legs 102 and 103 on the right side, a right lateral wall (an example of a right lateral guide) 132 is provided, which defines the right boundary of the parking space Ps. The function and structure of the right lateral wall (hereinafter referred to as the "right wall") 132 are the same as those of the left wall 130.

[0037] As shown in Figure 1, Station 1 is equipped with a first entry reflector 140, a second entry reflector 141, and a stopping reflector 145. Each reflector 140, 141, and 145 is used when the AMR2 enters and stops at Station 1. Each reflector 140, 141, and 145 is a reflective member that reflects light (incident light) and can reflect detection light emitted from the front sensor 23a mounted on the AMR2. Each reflector 140, 141, and 145 is composed of, for example, a prism reflector. Each reflector 140, 141, and 145 can reflect detection light with a higher brightness than objects around the AMR2. As a result, the AMR2 can distinguish and recognize the reflectors 140, 141, and 145 from other objects according to the brightness level of the reflected light.

[0038] The first entry reflector 140 is positioned on the left front leg 100, and the second entry reflector 141 is positioned on the right front leg 102. The first and second entry reflectors 140 and 141 are reflectors that guide the AMR2 as it approaches the entrance 120. The first and second entry reflectors 140 and 141 are positioned on the front of the legs 100 and 102 so as to face the AMR2 as it enters the parking space Ps. Specifically, the first and second entry reflectors 140 and 141 are positioned so that the centers of their reflective ranges θa1 and θa2 are aligned in the front-rear direction.

[0039] On the other hand, the stopping reflector 145 is located on the left wall 130 and is a reflector for stopping the AMR2 at a designated stopping position within the stopping space Ps. The stopping reflector 145 is located further back (rearward) in the stopping space Ps than the entry reflectors 140 and 141, as viewed from the perspective of the AMR2 entering the stopping space Ps. In the example shown in Figure 1, the stopping reflector 145 is located at the very back of the stopping space Ps, for example, at the same position as the left rear leg 101. This stopping reflector 145 is positioned facing the right wall 132. Specifically, the center of the reflective range θa3 of the stopping reflector 145 is positioned along the left-right direction, which is perpendicular to the direction of entry of the AMR2.

[0040] The first and second entry reflectors 140 and 141 have a convex shape that bulges forward so that they can be widely detected from the AMR2 before entering the parking space Ps. In contrast, the stopping reflector 145 has a planar shape. Therefore, the reflection ranges θa1 and θa2 of the first and second entry reflectors 140 and 141 are larger than the reflection range θa3 of the stopping reflector 145. Here, "reflection range" refers to the range of incidence angles in which reflected light of a certain intensity or higher can be maintained when detection light is incident on the reflector.

[0041] Station 1 may be equipped with at least three reflectors, including first and second approach reflectors 140, 141, and a stop reflector 145. For example, Station 1 may be equipped with a reflector that complements each of the three reflectors 140, 141, and 145. For example, AMR2 can detect the stop reflector 145 using the stop reflector 145 and a reflector that complements it. However, the components that complement the reflectors 140, 141, and 145 may be auxiliary components that allow identification by color, shape, etc.

[0042] In this configuration, Station 1 can support the pallet 5 being transported by AMR2 with the support section 110. When entering the parking space Ps, AMR2 controls the lifter drive unit 26 to lift the pallet 5 upward. Then, when it enters the parking space Ps and stops, AMR2 controls the lifter drive unit 26 to lower the pallet 5. This allows AMR2 to place the pallet 5 on Station 1. Note that when loading the pallet 5 onto the top plate 210 of AMR2, the lifter 27 is raised by the lifter drive unit 26. Therefore, after the pallet 5 is loaded onto the top plate 210, AMR2 may enter the parking space Ps with the pallet 5 still raised upward without lowering it.

[0043] The following describes the station entry method, which is a series of steps from entering the station 1 parking space Ps to stopping the AMR2, with reference to Figures 6 to 10. Here, Figures 6 and 7 are flowcharts showing the AMR's processing related to station entry. Figure 8 shows the AMR's movement until it reaches the scan position. Figure 9 shows the AMR's movement until it enters the parking space. Figure 10 shows the AMR's movement until it stops at the parking position.

[0044] In step S10 shown in Figure 6, the control unit 21 receives a movement command to station 1 via the wireless communication unit 22. The movement command is transmitted from the first processing machine 7 or the second processing machine 8 (see Figure 2) within the factory, or from an external device such as a management system that manages the factory's production.

[0045] In step S11, as shown in Figure 8, the control unit 21 moves the AMR2 from its current position to the scan position Psc by self-position estimation. Specifically, the control unit 21 estimates the current position of the AMR2 by matching map data with the detection results of sensors 23a and 23b. Then, the control unit 21 controls the drive motors 24a and 24b based on the self-position estimation result, enabling the AMR2 to move towards the scan position Psc.

[0046] The scan position Psc is predefined as a position and orientation such that the AMR2 is aligned with the entrance 120 of the parking space Ps, and the control unit 21 has information on the scan position Psc in advance. Under the control of the control unit 21, the AMR2 continues to move by estimating its own position, and the AMR2 can reach the scan position Psc.

[0047] In step S12 of Figure 6, the control unit 21 completes the positioning and angle determination of the AMR2 relative to the scan position Psc. There is some error in the movement of the AMR2 based on self-position estimation. Therefore, as shown in Figure 8, even when the control unit 21 has positioned and angled the AMR2 relative to the scan position Psc, a deviation of the AMR2 relative to the scan position Psc may occur.

[0048] In step S13 shown in Figure 6, the control unit 21 uses the front sensor 23a to search for the first and second entry reflectors 140 and 141.

[0049] In step S14, the control unit 21 determines the relative positions of the first and second approach reflectors 140 and 141 with respect to the AMR2 from the information of the first and second approach reflectors 140 and 141 detected by the sensor 23a. From the point cloud data detected by the sensor 23a, the distance from the AMR2 (sensor 23a) to the first and second approach reflectors 140 and 141, and the angles of the first and second approach reflectors 140 and 141 as seen from the AMR2 (sensor 23a) are determined. The control unit 21 determines the relative positional relationship of the first and second approach reflectors 140 and 141 from the distance and angle.

[0050] In step S15, the control unit 21 calculates the drive amount of the pair of drive motors 24a and 24b based on the relative positional relationship of the first and second entry reflectors 140 and 141. As shown in Figure 9, the control unit 21 calculates the drive amount of the pair of drive motors 24a and 24b so that the center Ct of the AMR2 coincides with a reference position Rp defined between the first and second entry reflectors 140 and 141, for example, the center position. Then, the control unit 21 controls the drive motors 24a and 24b according to the calculated drive amount to move the AMR2 forward. In the example shown in Figure 9, of the pair of wheels 25a and 25b, one wheel 25a corresponds to the left wheel in the direction of travel, and the other wheel 25b corresponds to the right wheel in the direction of travel.

[0051] In step S16 shown in Figure 6, the control unit 21 determines whether the AMR2 has reached the approach position Pap. As shown in Figure 9, the approach position Pap is set a certain distance La before the entrance 120 of the parking space. As shown in Figure 6, if it is determined that the AMR2 has not reached the approach position Pap (S16: NO), the control unit 21 performs the processes in steps S17 and S18, and then repeats the process in step S16. On the other hand, if it is determined that the AMR2 has reached the approach position Pap (S16: YES), the control unit 21 performs the process in step S19, which will be described later.

[0052] In step S17, the control unit 21 uses the sensor 23a to confirm the positions of the first and second entry reflectors 140 and 141 while the AMR2 is moving. Then, in step S18, the control unit 21 adjusts the drive amount of the pair of drive motors 24a and 24b.

[0053] As shown in Figure 9, if the AMR2 is shifted to the right of the reference position Rp, the control unit 21 adjusts the drive amounts of the pair of drive motors 24a and 24b so that the drive amount of the right drive motor 24b is greater than the drive amount of the left drive motor 24a. On the other hand, if the AMR2 is shifted to the left of the reference position Rp, the control unit 21 adjusts the drive amounts of the pair of drive motors 24a and 24b so that the drive amount of the left drive motor 24a is greater than the drive amount of the right drive motor 24b. Furthermore, if the reference position Rp and the AMR2 are approximately aligned, the control unit 21 adjusts the drive amounts of the pair of drive motors 24a and 24b so that the drive amounts of the left and right drive motors 24a and 24b are equal.

[0054] In this way, by adjusting the drive amount of the pair of drive motors 24a and 24b, the AMR2 approaches the approach position Pap, bringing the center Ct of the AMR2 closer to the reference position Rp. The AMR2 can switch its course according to the difference in the rotational speed of the pair of wheels 25a and 25b, rather than steering them. Therefore, as it approaches the approach position Pap, the AMR2 moves forward while swerving from side to side.

[0055] In step S19 shown in Figure 7, the control unit 21 uses the sensor 23a to search for the left wall 130 of station 1. In step S20, the control unit 21 determines whether or not the left wall 130 of station 1 has been found. If the left wall 130 is not found (S20: NO), the control unit 21 performs the process in step S21 and then repeats the process in step S20. On the other hand, if the left wall 130 is found (S20: YES), the control unit 21 performs the process in step S22.

[0056] In step S21, the control unit 21 calculates the drive amount of the pair of drive motors 24a and 24b to move the AMR2 forward. When the AMR2 is within the range where the first and second entry reflectors 140 and 141 can be detected by the sensor 23a, the control unit 21 calculates the drive amount of the pair of drive motors 24a and 24b based on the relative positional relationship of the first and second entry reflectors 140 and 141. On the other hand, as shown in Figure 9, when the AMR2 moves forward and the first and second entry reflectors 140 and 141 can no longer be detected by the sensor 23a, the control unit 21 calculates the drive amount of the pair of drive motors 24a and 24b so that the AMR2 moves in a straight line.

[0057] In step S22 shown in Figure 7, the control unit 21 calculates the drive amount of the pair of drive motors 24a and 24b based on the information of the left wall 130. As shown in Figure 10, the control unit 21 calculates the drive amount of the pair of drive motors 24a and 24b so that the distance dsw between the AMR2 and the side wall 130 becomes a predetermined reference value. Then, the control unit 21 controls the drive motors 24a and 24b according to the calculated drive amount to move the AMR2 forward.

[0058] In step S23 shown in Figure 7, the control unit 21 uses the sensor 23a to search for the stop reflector 145 and determines whether or not the stop reflector 145 has been found by the sensor 23a. If the stop reflector 145 is not found (S23: NO), the control unit 21 performs the processes in steps S24 and S25, and then repeats the process in step S23. On the other hand, if the stop reflector 145 is found (S23: YES), the control unit 21 performs the process in step S26.

[0059] In step S24, the control unit 21 uses the sensor 23a to check the distance dsw to the left wall 130 while the AMR2 is moving. Then, in step S25, the control unit 21 adjusts the drive amount of the pair of drive motors 24a and 24b so that the distance dsw between the AMR2 and the side wall 130 becomes a reference value.

[0060] As shown in Figure 10, if the distance dsw between the AMR2 and the side wall 130 is greater than the reference value, the AMR2 will travel in a direction that moves towards the left wall 130 so that the distance dsw approaches the reference value. As the distance dsw approaches the reference value, the orientation of the AMR2 will move closer to being parallel to the front-rear direction.

[0061] In step S26 shown in Figure 7, the control unit 21 determines whether the position of the stop reflector 145 as seen from the AMR2 is within the appropriate range. As shown in Figure 10, the distance dm from the AMR2 to the stop reflector 145 and the angle θc of the stop reflector 145 as seen from the AMR2 are detected by the sensor 23a. The control unit 21 determines that the position of the stop reflector 145 is within the appropriate range if the distance dm is less than or equal to a predetermined determination distance and the angle θc is greater than or equal to a predetermined determination angle.

[0062] If the position of the stop reflector 145 is not within the appropriate range (S26: NO), the control unit 21 performs the processes in steps S27 and S28, and then repeats the process in step S26. On the other hand, if the position of the stop reflector 145 is within the appropriate range (S26: YES), the control unit 21 performs the process in step S29.

[0063] In step S27, the control unit 21 uses the sensor 23a to confirm the position of the stop reflector 145 while the AMR2 is moving. Then, in step S28, the control unit 21 adjusts the drive amount of the pair of drive motors 24a and 24b so that the position of the stop reflector 145 is within the appropriate range.

[0064] In step S29, the control unit 21 stops the pair of drive motors 24a and 24b, thereby stopping the movement of the AMR2. As a result, the AMR2 comes to a precise stop in the designated position and orientation within the parking space Ps.

[0065] As described above, according to this embodiment, Station 1 is provided with first and second entry reflectors 140 and 141, and a stopping reflector 145. The first and second entry reflectors 140 and 141 are positioned on the front legs 100 and 102 so as to face the AMR2 entering the entrance 120 of the parking space Ps. The stopping reflector 145 is positioned on the left wall 130 so as to face the right wall 132.

[0066] With this configuration, the first and second entry reflectors 140 and 141, positioned facing the AMR2, allow the AMR2 to properly recognize the entrance 120 of the parking space Ps. At this time, the stop reflector 145 is positioned on the left wall 130 facing the right wall 132, making it difficult for the AMR2 to detect it before it enters the entrance 120. Therefore, when the AMR2 enters the entrance 120, the stop reflector 145 is detected, and misidentification of it as an entry reflector 140 or 141 is suppressed. This allows the AMR2 to enter the entrance 120 accurately.

[0067] Furthermore, a stop reflector 145 is provided on the left wall 130. When the AMR2 enters the parking space Ps, it can use this stop reflector 145 to accurately stop the AMR2 at the correct position within the parking space Ps.

[0068] As described above, according to the transport system of this embodiment, by having the above-described structure of station 1, the AMR2 can autonomously drive and accurately enter and stop in front of station 1.

[0069] In this embodiment, the stopping reflector 145 is positioned further into the parking space Ps than the first and second entry reflectors 140 and 141, as viewed from the AMR2 entering the parking space Ps.

[0070] With this configuration, the stop reflector 145 is positioned at the back of the parking space Ps, so that it is difficult for the sensor 23a of the AMR2 to see it as it travels towards the entrance 120. This prevents the AMR2 from mistakenly recognizing the stop reflector 145 as the entrance reflectors 140 and 141 when it travels towards the entrance 120. Therefore, the AMR2 can accurately enter the parking space Ps of Station 1.

[0071] In this embodiment, the sensor 23a is mounted on the left end, which is one of the left and right ends of the front of the AMR2 in the direction of travel FW. The side wall on which the stopping reflector 145 is provided is the left wall 130, which is on the same side as the sensor 23a mounted on the AMR2, as viewed from the AMR2 entering the parking space Ps, out of the left and right side walls 130 and 132.

[0072] If the stop reflector 145 is installed on the right wall 132, which is opposite to the sensor 23a mounted on the AMR2, the stop reflector 145 will be in a position that is easily visible to the sensor 23a when the AMR2 is traveling toward the entrance 120. On the other hand, according to the configuration of this embodiment, since the stop reflector 145 and the sensor 23a are located on the same side, the stop reflector 145 will be in a position that is difficult to see from the sensor 23a when the AMR2 is traveling toward the entrance 120. Therefore, it is possible to suppress the misidentification of the stop reflector 145 as the entrance reflectors 140 and 141 when the AMR2 is traveling toward the entrance 120. Consequently, the AMR2 can accurately enter the parking space Ps of Station 1.

[0073] In this embodiment, the reflective range of the first and second entry reflectors 140 and 141 is greater than the reflective range of the stop reflector 145.

[0074] With this configuration, the AMR2 traveling towards the entrance 120 can detect the first and second entrance reflectors 140 and 141 from a wide range. As a result, the AMR2 can properly recognize the entrance 120 of the parking space Ps. Furthermore, since the reflective range of the stop reflector 145 is limited, it is difficult for the sensor 23a of the AMR2 traveling towards the entrance 120 to detect the stop reflector 145. Therefore, when the AMR2 is traveling towards the entrance 120, it is possible to suppress the misrecognition of the stop reflector 145 as the entrance reflectors 140 and 141. Consequently, the AMR2 can accurately enter the parking space Ps of station 1.

[0075] In this embodiment, the left and right lateral guides are composed of lateral walls 130 and 132 that extend parallel to the entry direction of the AMR2.

[0076] As described above, the stop reflector 145 is positioned at the back of the parking space Ps so that it is difficult for the AMR2 to detect it as it enters the parking space Ps. Therefore, the sensor 23a of the AMR2 cannot detect the stop reflector 145 until it has driven for a while after entering the parking space Ps. On the other hand, a left wall 130 extends to the left side of the parking space Ps. Therefore, by driving while checking the distance from the left wall 130, the AMR2 can accurately drive within the parking space Ps until it detects the stop reflector 145.

[0077] In this embodiment, Station 1 is provided with a lateral wall 132 that extends continuously from the entrance 120 to the stop reflector 145, parallel to the direction of entry of the AMR2, as a lateral guide defining the left side of the parking space Ps. However, the structure of the lateral guide of Station 1 is not limited to this.

[0078] Figure 11 illustrates another example of a lateral guide for a station. The lateral guides defining the left and right boundaries of the parking space Ps may be configured such that intermediate structures 104 are intermittently provided between the front and rear legs 100, 101. That is, the AMR2 only needs to travel in a manner that maintains a constant separation distance dv from structures within the detection range Rd of the sensor 23a, and the lateral guides only need to have at least one intermediate structure 104 within the detection range Rd of the sensor 23a as seen from the traveling AMR2.

[0079] Figure 12 illustrates another example of a lateral guide for a station. In the example shown in Figure 12, the left wall 130 of station 1 is not a smooth surface extending in the direction of entry for AMR2, but rather has an uneven surface. Through calculations by the control unit 21, AMR2 can define a spatial Rdt in front of and to the left of AMR2 by converting the orthogonal coordinate system detected by sensor 23a into an XY axis orthogonal coordinate system. By performing such a coordinate transformation, AMR2 can enter the parking space Ps of station 1 using the same procedure as in the embodiment described above, even if the left wall 130 is uneven, by tracking the distance in the X direction in spatial Rdt.

[0080] In this embodiment, the AMR2 includes a control unit 21 that controls the movement of the AMR2 based on the detection results of the sensor 23a.

[0081] With this configuration, autonomous driving of the AMR2 can be achieved through the control of the control unit 21.

[0082] In this embodiment, when the AMR2 is traveling toward the entrance 120 of the station 1, the control unit 21 controls the movement of the AMR2 based on the relative positions of the first and second entrance reflectors 140 and 141 with respect to the AMR2, which are detected by the sensor 23a.

[0083] With this configuration, the control unit 21 can recognize the entrance 120 to the parking space Ps by detecting the first and second entrance reflectors 140 and 141. By recognizing the relative position with respect to the first and second entrance reflectors 140 and 141, the control unit 21 can accurately drive the AMR2 toward the entrance 120.

[0084] In this embodiment, when the AMR2 approaches the entrance 120, the control unit 21 uses the sensor 23a to search for the left wall 130 and controls the movement of the AMR2 based on the distance dsw to the left wall 130.

[0085] As described above, the stop reflector 145 is positioned at the back of the parking space Ps so that it is difficult for the AMR2 to detect it as it enters the parking space Ps. Therefore, the sensor 23a of the AMR2 cannot detect the stop reflector 145 until it has driven for a while after entering the parking space Ps. On the other hand, the left wall 130 extends to the left side of the parking space Ps. Therefore, by having the control unit 21 drive while checking the distance to the left wall 130, the AMR2 can be driven accurately within the parking space Ps until the stop reflector 145 is detected.

[0086] In this embodiment, when the control unit 21 detects the stop reflector 145 using the sensor 23a, it stops the AMR2 from moving based on the relative position of the stop reflector 145 with respect to the AMR2.

[0087] With this configuration, the control unit 21 can accurately stop the AMR2 at the appropriate position within the stopping space Ps by driving while confirming the relative position of the stopping reflector 145.

[0088] In this embodiment, the AMR2 further includes a map storage unit 29 that stores map data of the environment in which the AMR2 is traveling. The control unit 21 estimates the position of the AMR2 by matching the map data with the detection results of sensors 23a and 23b until it reaches a scan position Psc which is set to be a predetermined distance before the entrance 120 of the parking space Ps. Based on the estimation result, it controls the driving of the AMR2, and after reaching the scan position Psc, it drives toward the entrance 120.

[0089] With this configuration, the control unit 21 can autonomously reach the scan position Psc by estimating the AMR2's own position. Once it reaches the scan position Psc, the control unit 21 can accurately drive the AMR2 toward the parking space Ps by utilizing the station 1 with the above structure.

[0090] The transport system according to this embodiment has been described above, but the station 1 and station access method used in the transport system described above are also included in one aspect of this embodiment.

[0091] The station 1 according to this embodiment is provided above a parking space Ps into which an AMR2 transporting a pallet 5 enters and stops, and includes a support section 110 on which a pallet 5 can be placed, left and right legs 100, 102 positioned spaced apart to the left and right from the perspective of the AMR2 entering the parking space Ps, defining an entrance 120 to the parking space Ps, left and right lateral guides provided along the direction in which the AMR2 enters the parking space Ps, defining the left and right boundaries of the parking space Ps, and at least three reflectors 140, 141, 145 that reflect detection light emitted from a sensor 23a for autonomous driving of the AMR2. The three reflectors 140, 141, and 145 include a first entry reflector 140 positioned on one of the left and right legs 100, 102, a second entry reflector 141 positioned on the other leg 102, and a stop reflector 145 positioned on one of the left and right lateral guides. The first and second entry reflectors 140 and 141 are positioned facing the AMR entering the parking space Ps, and the stop reflector 145 is positioned facing the other lateral guide.

[0092] The station entry method according to this embodiment is a station entry method that causes an AMR2, whose movement is autonomously controlled by a computer, to enter station 1. Station 1 is provided with a support section 110 on which a pallet 5 can be placed, above a stopping space Ps for the AMR2 to enter and stop to transport the pallet 5. The station entry method includes detecting a first entry reflector 140 and a second entry reflector 141 located on the left and right sides of the entrance 120 to the parking space Ps using a sensor 23a that detects surrounding objects by receiving reflected light from detection light irradiated into the surroundings, driving the AMR2 toward the entrance 120 based on the relative positions of the first and second entry reflectors 140 and 141 with respect to the AMR2 detected by the sensor 23a, and when the AMR2 approaches the entrance 120, detecting one of the left and right lateral guides that define the left and right boundaries of the parking space Ps using the sensor 23a, driving the AMR2 toward the entrance 120 using the distance dsw to the one lateral guide detected by the sensor 23a, detecting a stop reflector 145 located on the one lateral guide using the sensor 23a, and stopping the AMR2's movement based on the relative position of the stop reflector 145 with respect to the AMR2 detected by the sensor 23a.

[0093] According to the station 1 and station entry method of this embodiment, the AMR2 can autonomously drive and accurately enter the parking space Ps of station 1.

[0094] As described above, embodiments of the present invention have been presented, but the statements and drawings that constitute part of this disclosure should not be understood as limiting the invention. Various alternative embodiments, examples, and operational techniques will become apparent to those skilled in the art from this disclosure. [Explanation of Symbols]

[0095] 1 Station (Station for transport vehicles) 2 AMR (Transport Vehicle) 5 pallets (transported goods) 7 1st processing machine 8 Second processing machine 21 Control Unit 22 Wireless Communication Section 23a, 23b sensors 24a, 24b drive motors 25a, 25b wheels 26 Lifter drive unit 27 Lifter 29 Map storage unit 100, 101, 102, 103 Legs 104 Intermediate structure 110 Support part 120 Entrance 130 Left wall (side wall (side guide)) 132 Right wall (side wall (side guide)) 140 First approach reflector (first reflector) 141 2nd approach reflector (2nd reflector) 145 Stop reflector (third reflector) 200 vehicles 210 Top plate Ct center dm Distance to the stop reflector distance to the left wall (dsw) dv constant separation distance FW direction of travel La fixed distance Pap approach location Ps Parking space PSC scan location R1 Rotation direction Rd detection range Rp Reference position θa1 Reflection range θa² Reflection range θa3 Reflection range θb1 detection range θb2 detection range θc Angle of the stop reflector

Claims

1. A transport vehicle that autonomously moves and transports objects based on the detection results of a sensor that detects surrounding objects by receiving reflected light from detection light irradiated into the surroundings, The station comprises a station that forms a parking space for the transport vehicle to enter and stop, and above the parking space, a support section on which the transported object can be placed, The aforementioned station is The left and right structures are positioned spaced apart to the left and right of the transport vehicle entering the parking space, and define the entrances to the parking space. The transport vehicle is provided along the direction of entry into the parking space, and the left and right lateral guides define the left and right boundaries of the parking space, A first reflector is provided in one of the left and right structures, which reflects the detected light, A second reflector is provided in the other structure of the left and right structures, which reflects the detected light, It includes a third reflector plate positioned on one of the left and right lateral guides and reflecting the detection light, The first reflector and the second reflector are positioned on the front surfaces of the left and right structures such that the centers of the reflective ranges of the first reflector and the second reflector are aligned with the direction of entry of the transport vehicle entering the parking space. The third reflector is positioned at the rear of the parking space and facing the other lateral guide, and is a reflector for stopping the transport vehicle at a predetermined parking position within the parking space. Conveyor system.

2. The third reflector is positioned further back in the parking space than the first and second reflectors, as viewed from the perspective of the transport vehicle entering the parking space. The transport system according to claim 1.

3. The sensor is mounted on one of the left or right ends of the front of the transport vehicle in the direction of entry. The one lateral guide on which the third reflector is provided is, of the left and right lateral guides, the lateral guide on the same side as the sensor mounted on the transport vehicle, as viewed from the transport vehicle entering the parking space. The transport system described in claim 1.

4. The reflective ranges of the first and second reflectors are greater than the reflective range of the third reflector. The transport system described in claim 1.

5. The aforementioned lateral guide is composed of a lateral wall extending parallel to the direction of entry. The transport system described in claim 1.

6. The aforementioned transport vehicle is Includes a control unit that controls the movement of the transport vehicle based on the detection results of the aforementioned sensor. The transport system described in claim 1.

7. The control unit, When traveling toward the entrance of the station, the movement of the transport vehicle is controlled based on the relative positions of the first and second reflectors with respect to the transport vehicle, as detected by the sensor. The transport system described in claim 6.

8. The control unit, When the transport vehicle approaches the entrance, the sensor searches for one of the lateral guides, The transport vehicle's movement is controlled based on the distance to the aforementioned lateral guide. The transport system described in claim 7.

9. The control unit, When the third reflector is detected by the sensor, the vehicle is stopped based on the relative position of the third reflector with respect to the transport vehicle. The transport system described in claim 8.

10. The aforementioned transport vehicle is The system further includes a map storage unit that stores map data of the environment in which the transport vehicle travels, The control unit, Until the vehicle reaches a scan position set a predetermined distance before the entrance, the position of the transport vehicle is estimated from the matching of the map data and the detection results of the sensor, and the movement of the transport vehicle is controlled based on the estimation result. After reaching the aforementioned scan position, it travels toward the aforementioned entrance. The transport system described in claim 7.

11. A support section is provided above a parking space where a transport vehicle carrying transported goods enters and stops, and on which the transported goods can be placed. The left and right structures are positioned spaced apart to the left and right of the transport vehicle entering the parking space, and define the entrances to the parking space. The transport vehicle is provided along the direction of entry into the parking space, and the left and right lateral guides define the left and right boundaries of the parking space, The transport vehicle comprises at least three reflectors that reflect detection light emitted from sensors for autonomous driving, The three reflectors mentioned above are, A first reflector is placed in one of the left and right structures, A second reflector is disposed in the other structure of the left and right structures, It includes a third reflector plate positioned on one of the left and right lateral guides, The first reflector and the second reflector are positioned on the front surfaces of the left and right structures such that the centers of the reflective ranges of the first reflector and the second reflector are aligned with the direction of entry of the transport vehicle entering the parking space. The third reflector is positioned at the rear of the parking space and facing the other lateral guide, and is a reflector for stopping the transport vehicle at a predetermined parking position within the parking space. Station for transport vehicles.

12. In a station entry method in which a transport vehicle whose movement is autonomously controlled by a computer enters a station, The station is provided with a support section above a parking space for a transport vehicle to enter and stop, on which the transported goods can be placed. A first reflector and a second reflector are located on the left and right front sides of the entrance to the parking space, and the center of the reflection range is positioned along the direction in which the transport vehicle enters the parking space. These reflectors are detected by a sensor that receives reflected light from detection light irradiated around them to detect surrounding objects. Based on the relative positions of the first and second reflectors with respect to the transport vehicle detected by the sensor, the transport vehicle is driven toward the entrance. When the transport vehicle approaches the entrance, the sensor detects one of the left and right lateral guides that define the left and right boundaries of the parking space. Based on the distance to the one lateral guide detected by the sensor, the transport vehicle is driven. The sensor detects a third reflector, which is a reflector for stopping the transport vehicle at a predetermined stopping position within the parking space, which is positioned on one of the lateral guides at the rear of the parking space, facing the other lateral guide. Based on the relative position of the third reflector with respect to the transport vehicle detected by the sensor, the transport vehicle is stopped from moving. Station entry procedures.

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