Automated guided vehicle, cargo handling system, and method for controlling an automated guided vehicle

Abstract

This stabilizes the switch to magnetic guidance immediately after turning using laser guidance. [Solution] The vehicle control unit of the automated guided vehicle (AGV) 2 uses laser guidance to turn the AGV 2 from the turning start position P1 to the turning end position P2, and then uses laser guidance to move to the confirmation position P4. At the confirmation position P4, the vehicle control unit 30 calculates the amount of lateral displacement of the AGV 2 relative to the travel path R in the magnetic guidance section based on the output of the optical sensor for laser guidance. If the amount of lateral displacement is less than or equal to a threshold, the vehicle control unit 30 moves the AGV 2 from the confirmation position P4 to the switching position P5, and switches from laser guidance to magnetic guidance at the switching position P5. If the amount of lateral displacement is greater than the threshold, the vehicle control unit 30 causes the AGV 2 to perform a switchback operation using laser guidance, moving backward from the confirmation position P4 to a separation position P3 located linearly behind the turning end position P2, and then forward from the separation position P3 to the confirmation position P4.

Description

Technical Field

[0001] This application relates to an automated guided vehicle, a material handling system, and a method for controlling an automated guided vehicle.

Background Art

[0002] As disclosed in Patent Document 1, an automated guided vehicle that travels along a travel route using a plurality of guidance methods in combination is known. The automated guided vehicle can travel using SLAM guidance, laser guidance, and magnetic guidance.

[0003] The automated guided vehicle in Patent Document 1 travels in the SLAM guidance section using SLAM guidance and then switches to magnetic guidance to travel in the magnetic guidance section. In the magnetic guidance section, a magnetic body such as a magnetic tape is laid along the travel route. A switching preparation section is provided between the SLAM guidance section and the magnetic guidance section.

[0004] When the automated guided vehicle reaches the switching preparation section after traveling in the SLAM guidance section, it first calculates the lateral displacement amount (magnetic guidance deviation) of the automated guided vehicle with respect to the travel route in the magnetic guidance section and travels using SLAM guidance so that the magnetic guidance deviation becomes small in the switching preparation section. Then, when the automated guided vehicle reaches the magnetic guidance section after traveling in the switching preparation section, it switches from SLAM guidance to magnetic guidance and travels in the magnetic guidance section. This prevents the automated guided vehicle from colliding with surrounding equipment when switching the guidance method.

[0005] By the way, as an automated guided vehicle, a material handling system that employs an automated forklift and causes the automated forklift to perform material handling is also known (Patent Documents 2, 3, etc.). For example, the automated forklift travels in a wide main passage using laser guidance and travels in a branch passage (narrow passage) such as between racks using magnetic guidance.

[0006] Cargo handling systems often employ layouts that enhance storage efficiency. In this case, after navigating the main aisle's turning section using laser guidance, the system switches to magnetic guidance to enter a branch aisle (narrow passage). At this point, the automated guided vehicle (AGV) (its center) needs to be aligned with the center of the branch aisle immediately after turning. However, due to the effects of uneven road surfaces and the unique characteristics (quirks) of each AGV, the AGV may shift laterally from its center position after turning.

[0007] If an automated guided vehicle (AGV) enters a branch passage (narrow passage) while shifting laterally from its center position, there is a risk of interference with equipment. Therefore, after turning, if the amount of lateral displacement exceeds a threshold, or if the obstacle sensor detects equipment or other obstacles, the AGV stops its automatic operation to avoid interference with equipment. However, if such operation stops occur frequently, work efficiency will be poor.

[0008] While it is conceivable to provide a switching preparation section, as described in Patent Document 1 above, between the turning end position and the branch passage, prioritizing the stability (continuity) of automated operation requires a longer switching preparation section. However, this is undesirable from the standpoint of storage efficiency.

[0009] In addition, rack-fork type unmanned forklifts are sometimes used. Rack-fork type unmanned forklifts can point their forks in three directions—forward, left, and right—without changing the orientation of the vehicle, enabling loading and unloading in three directions. With rack-fork type unmanned forklifts, the width of the aisles between racks (narrow aisles) is only about half that of a normal forklift, which can improve storage efficiency and workability. [Prior art documents] [Patent Documents]

[0010] [Patent Document 1] Japanese Patent Publication No. 2021-47670 [Patent Document 2] Japanese Patent Publication No. 2023-47501 [Patent Document 3] Japanese Patent Publication No. 2019-112212 [Patent Document 4] Japanese Patent Publication No. 2002-123316 [Overview of the project] [Problems that the invention aims to solve]

[0011] The purpose of this invention is to stabilize the switch to magnetic guidance immediately after turning using laser guidance. [Means for solving the problem]

[0012] This invention provides an automated guided vehicle that travels along a travel path using laser guidance based on the output of an optical sensor and magnetic guidance based on the output of a magnetic sensor. The aforementioned automated guided vehicle is The vehicle is equipped with a vehicle control unit that controls the operation of the automated guided vehicle, The vehicle control unit, The automated guided vehicle is rotated from the rotation start position to the rotation end position using the laser guidance. The vehicle is guided by the aforementioned laser to a confirmation position beyond the turning end position, At the aforementioned confirmation position, based on the output of the optical sensor, the amount of lateral displacement of the automated guided vehicle relative to the travel path in the magnetic induction section beyond the confirmation position is determined. If the aforementioned lateral displacement is less than or equal to the threshold, The automated guided vehicle is driven from the confirmation position to a switching position beyond the confirmation position, and at the switching position, the guidance is switched from laser guidance to magnetic guidance. If the amount of lateral displacement is greater than the threshold, The automated guided vehicle (AGV) is instructed by the laser to perform a switchback operation, moving backward from the confirmation position to a detached position located linearly behind the turning end position, and then forward from that detached position to the confirmation position.

[0013] For example, the aforementioned automated guided vehicle is an automated forklift, A fork and It may be provided with a loading and unloading device that lifts, shifts left and right, and rotates the fork. And the vehicle control unit determines whether the fork is facing the fork entry direction for the next loading and unloading based on the work information related to the loading and unloading, When the fork is facing the fork entry direction, after turning, the driverless transport vehicle is caused to travel from the turning end position to the confirmation position by the laser guidance, When the fork is not facing the fork entry direction, after turning, the driverless transport vehicle is caused to reverse from the turning end position to the separation position, the fork is directed in the fork entry direction by the loading and unloading device at the separation position, and the driverless transport vehicle may be caused to advance from the separation position to the confirmation position.

[0014] For example, after the vehicle control unit performs the switchback operation a specified number of times, if the lateral displacement amount determined at the confirmation position is greater than the threshold value, the driverless transport vehicle may be stopped. When the lateral displacement amount determined at the confirmation position is greater than the threshold value after the vehicle control unit performs the switchback operation a specified number of times, the driverless transport vehicle may be stopped.

[0015] Further, the present application provides a loading and unloading system, The loading and unloading system includes the above-described driverless transport vehicle (driverless forklift) and racks provided along both sides of the magnetic induction section.

[0016] Further, the present application provides a control method for causing a driverless transport vehicle to travel along a travel route based on laser guidance based on the output of an optical sensor and magnetic induction based on the output of a magnetic sensor. The control method causes the driverless transport vehicle to turn from a turning start position to a turning end position by the laser guidance, causes the vehicle to travel to a confirmation position beyond the turning end position by the laser guidance, At the confirmation position, based on the output of the optical sensor, determine the amount of lateral deviation of the automated guided vehicle with respect to the travel path in the magnetic induction section ahead of the confirmation position. When the amount of lateral deviation is less than or equal to the threshold value, Drive the automated guided vehicle from the confirmation position to a switching position ahead of the confirmation position, and switch from the laser guidance to the magnetic induction at the switching position. When the amount of lateral deviation is greater than the threshold value, Cause the automated guided vehicle to perform a switchback operation of retreating from the confirmation position to a separation position linearly behind and beyond the turning end position, and then advancing from the separation position to the confirmation position by laser guidance.

[0017] For example, the automated guided vehicle is an automated forklift, with forks, and a cargo handling device that lifts, shifts left and right, and rotates the forks. And the control method Determine whether the forks are facing the fork entry direction for the next cargo handling based on the work information related to the cargo handling, When the forks are facing the fork entry direction, After turning, drive the automated guided vehicle from the turning end position to the confirmation position by laser guidance. When the forks are not facing the fork entry direction, After turning, drive the automated guided vehicle from the turning end position to the separation position, use the cargo handling device to turn the forks in the fork entry direction at the separation position, and then drive the automated guided vehicle from the separation position to the confirmation position.

[0018] For example, the control method After performing the switchback operation a specified number of times, if the amount of lateral deviation determined at the confirmation position is greater than the threshold value, the automated guided vehicle may be stopped.

Brief Description of the Drawings

[0019] [Figure 1] Figure 1 is a schematic diagram partially illustrating an example cargo handling system. [Figure 2] Figure 2 is a schematic side view of an example automated guided vehicle (unmanned forklift). [Figure 3] Figure 3 is a block diagram showing the configuration of an example automated guided vehicle (AGV). [Figure 4] Figures 4A and 4B illustrate the operation for magnetic induction switching. [Figure 5] Figures 5A to 5C illustrate the operation for magnetic induction switching. [Figure 6] Figures 6A and 6B illustrate the operation for magnetic induction switching. [Figure 7] Figure 7 is a flowchart illustrating an example of magnetic induction switching processing. [Figure 8] Figure 8 is a flowchart illustrating an example of magnetic induction switching processing. [Modes for carrying out the invention]

[0020] Embodiments of the present invention will be described below with reference to the attached drawings. The following are merely illustrative examples of the present invention. The drawings are schematic and may not be drawn to exact size. It should also be understood that the same reference numerals are used throughout the drawings to represent identical or similar components.

[0021] Figure 1 shows an exemplary cargo handling system in part and schematicly. The cargo handling system 1 includes at least one unmanned forklift 2 (an example of an automated guided vehicle) that operates automatically in a facility 10 such as a warehouse, and a management device 11 (management server) that manages the unmanned forklift 2 and transmits cargo handling work information to the unmanned forklift 2 wirelessly.

[0022] Within facility 10, racks 12 are provided on which cargo W is placed. The unmanned forklift 2 travels along the travel path R within facility 10 according to work information, and performs cargo handling operations such as placing cargo W on racks 12 or taking cargo W from racks 12. Within facility 10, there is a main passage 13 and branch passages 14 that branch off from the main passage 13. In this example, the branch passage 14 is a narrow passage, a straight passage formed between them by the racks 12.

[0023] In Figure 1, the main passage 13 of the travel route R is shown by a black line, and the branch passage 14 of the travel route R is shown by a gray line. In the travel route R shown in Figure 1, a branch passage 14 (narrow passage) is provided immediately after the turning section of the main passage 13 (the section from position P1 to position P2) from the viewpoint of improving storage efficiency.

[0024] As described below, the unmanned forklift 2 travels along the main aisle 13 using laser guidance, turns, switches from laser guidance to magnetic guidance, enters the branch aisle 14 using magnetic guidance, travels along the branch aisle 14, and performs loading and unloading operations on the rack 12. In other words, the branch aisle 14 is a magnetic guidance section.

[0025] As shown in Figure 2, the unmanned forklift 2 comprises a vehicle body 20, a running gear 22 for driving and steering the drive wheels 21 to move the vehicle body 20, forks 23 provided at the front of the vehicle body 20 for supporting the load W, and a load handling device 24 provided at the front of the vehicle body 20 for moving the forks 23.

[0026] In this embodiment, the unmanned forklift 2 is a rack-fork type unmanned forklift. Therefore, the cargo handling device 24 includes a lift mechanism 25 (mast mechanism) for lifting (raising and lowering) the forks 23, a shift mechanism 26 for shifting the forks 23 in the left-right direction of the vehicle body 20, and a rotate mechanism 27 for rotating the forks 23. As a result, the unmanned forklift 2 can orient the forks 23 in three directions—forward, left, and right—without changing the orientation of the vehicle body 20. Therefore, the rack-fork type unmanned forklift 2 is very suitable for cargo handling work in branch passages 14 (narrow passages) as shown in Figure 1.

[0027] The unmanned forklift 2 is equipped with an optical sensor 28 for laser guidance. The optical sensor 28 is a laser scanner that projects laser light horizontally over a 360° radius around it and receives the laser light reflected by multiple reflectors (not shown) placed on structures such as walls 15 (Figure 1) and columns within the facility 10.

[0028] The unmanned forklift 2 is equipped with a magnetic sensor 29 for magnetic guidance. The magnetic sensor 29 is configured to detect a line-shaped magnetic material 16 (Figure 1) provided along the travel path R in the branch passage 14. The line-shaped magnetic material 16 is, for example, a magnetic tape laid on the floor or a magnetic rod embedded in the floor. The magnetic material 16 is provided so as to extend from the branch passage 14 into the main passage 13.

[0029] In this embodiment, three magnetic sensors 29 are provided at appropriate intervals in the front-rear direction of the unmanned forklift 2, but this is not the only configuration. The number and arrangement of the magnetic sensors 29 can be determined appropriately depending on the characteristics of the magnetic induction section and the configuration of the unmanned forklift 2.

[0030] The unmanned forklift 2 is further equipped with a control device 3 for controlling the operation of the unmanned forklift 2.

[0031] As shown in Figure 3, the control device 3 comprises a vehicle control unit 30 for controlling the operation of the unmanned forklift 2 and a storage medium 31 for storing various information. The vehicle control unit 30 is composed of a microprocessor (MPU) and is realized by executing a program stored in the storage medium 31. The vehicle control unit 30 includes a driving control unit 300 and a cargo handling control unit 301.

[0032] The travel control unit 300 controls the travel device 22 based on the output of the optical sensor 28, thereby controlling the movement of the unmanned forklift 2. Specifically, the travel control unit 300 determines the current position of the unmanned forklift 2 based on the reflected light received by the optical sensor 28 (laser scanner). Then, while referring to its determined current position, the travel control unit 300 controls the travel device 22 to move the unmanned forklift 2 along the travel path R, adjusting its posture so that the center of its body 20 does not shift relative to the travel path R. With this configuration, the unmanned forklift 2 can travel along the main passage 13 (laser guidance section) of the travel path R using laser guidance according to work information related to cargo handling.

[0033] The travel control unit 300 controls the travel device 22 based on the output of the magnetic sensor 29 that detects the magnetism of the magnetic material 16, and moves the unmanned forklift 2 along the linear magnetic material 16 while adjusting its posture so that the center of the vehicle body 20 does not shift relative to the linear magnetic material 16. With this configuration, the unmanned forklift 2 can travel along the linear magnetic material 16 by magnetic guidance according to the work information related to cargo handling, that is, it can travel along the section of the branch passage 14 (magnetic guidance section) of the travel path R by magnetic guidance.

[0034] The cargo handling control unit 301 controls the cargo handling device 24 according to the cargo handling work information, thereby controlling the movement of the forks 23. As a result, the unmanned forklift 2 can perform cargo handling operations on the rack 12.

[0035] The following describes the control system by which the unmanned forklift 2 turns along the main aisle 13 using laser guidance, then switches to magnetic guidance to enter the branch aisle 14.

[0036] As shown in Figure 1, the turning section of the travel path R is the section from the turning start position P1 to the turning end position P2. In addition, a switching position P5 is set for switching from laser guidance to magnetic guidance.

[0037] Confirmation position P4 is set ahead of the turning end position P2 and behind the switching position P5. Furthermore, separation position P3 is set linearly behind the turning end position P2. These positions P3, P2, P4, and P5 are on a straight line and lie on the extension of the straight section of the branch passage 14 of the travel path R.

[0038] Information regarding these positions P1 to P5 is stored in the storage medium 31. Therefore, the travel control unit 300 can recognize when the unmanned forklift 2 has reached each of the positions P1 to P5 based on its current position, which is determined based on the output of the optical sensor 28.

[0039] In Figures 4A and 4B, the unmanned forklift 2 is traveling along the main aisle 13 with the load W supported by the forks 23, entering the branch aisle 14, and attempting to perform a loading operation by placing the load W in the area T of the rack 12 on the right side relative to the direction of travel.

[0040] Figure 4A shows that the forks 23 are facing to the right with respect to the direction of travel, which coincides with the direction of fork entry into area T (entry direction). The unmanned forklift 2 can perform cargo handling operations by entering the branch aisle 14 with the forks 23 in this orientation.

[0041] On the other hand, in Figure 4B, the forks 23 are facing left with respect to the direction of travel, and do not coincide with the direction in which the forks enter area T. Even if the unmanned forklift 2 enters the branch passage 14 with the forks 23 facing this direction, it cannot change the direction of the forks 23 within the branch passage 14 (narrow passage), and therefore cannot perform cargo handling operations.

[0042] Therefore, control is first performed to orient the fork 23 in the direction of entry for the next cargo handling operation.

[0043] As shown in Figure 7, in the process of switching to magnetic induction, first, the vehicle control unit 30 determines whether the forks 23 are facing the direction of fork entry for the next load handling operation, based on the signal from the load handling device 24 indicating the current orientation of the forks 23 and the work information related to load handling from the management device 11 (S1).

[0044] When the forks 23 are facing the direction of fork entry as shown in Figure 4A (YES in S1), the vehicle control unit 30 uses laser guidance to turn the unmanned forklift 2 along the turning section from the turning start position P1 to the turning end position P2, and then moves it forward to the confirmation position P4 located beyond that point (S2) (Figure 5C).

[0045] When the forks 23 are not facing the direction of fork entry (NO in S1), as shown in Figure 4B, the vehicle control unit 30 uses laser guidance to turn the unmanned forklift 2 along the turning section from the turning start position P1 to the turning end position P2, and then moves it backward from the turning end position P2 to the distance position P3 (S3) (Figure 5A).

[0046] Next, the vehicle control unit 30 controls the cargo handling device 24 to shift and rotate the forks 23 so that the forks 23 are in the direction of entry for the next cargo handling operation without changing the orientation of the vehicle body 20 (S4) (Figure 5A → Figure 5B).

[0047] Next, the vehicle control unit 30 uses laser guidance to move the unmanned forklift 2 forward from the separation position P3 through the turning completion position P2 to the confirmation position P4 (S5) (Figure 5B → Figure 5C).

[0048] As described above, the unmanned forklift 2 reaches the confirmation position P4 with the orientation of the forks 23 aligned with the fork entry direction.

[0049] As described in the background technology, after turning, the unmanned forklift 2 (the center of its body 20) may be laterally displaced with respect to the travel path R (center line of the branch passage 14) in the magnetic guidance section, and if it attempts to enter the branch passage 14 with a large amount of lateral displacement (lateral displacement deviation), there is a risk of interference with equipment such as the rack 12. Therefore, the vehicle control unit 30 controls the unmanned forklift 2 as follows.

[0050] As shown in Figure 8, the vehicle control unit 30 stops the unmanned forklift 2 at the confirmation position P4 for a predetermined time (for example, 2 seconds) and determines the amount of lateral displacement of the unmanned forklift 2 (the center of its body 20) relative to the travel path R (the center line of the branch passage 14) in the magnetic induction section (S6). The vehicle control unit 30 calculates the amount of lateral displacement based on the current position of the unmanned forklift 2 identified based on the output of the optical sensor 28 and the position information (known) of the magnetic induction section of the travel path R.

[0051] Next, the vehicle control unit 30 determines whether the calculated lateral displacement is less than or equal to a predetermined threshold (S7).

[0052] If the amount of lateral displacement is below a threshold (YES in S7), the vehicle control unit 30 resets the count for the switchback operation described later (to zero) (S8), moves forward from the confirmation position P4 to the switching position P5 using laser guidance (S9) (Figure 5C → Figure 6A), and switches from laser guidance to magnetic guidance at the switching position P5 (S10).

[0053] After switching to magnetic guidance, the vehicle control unit 30 enters the branch passage 14 (magnetic guidance section) using magnetic guidance, drives the vehicle, and performs cargo handling. In the examples shown in Figures 4 to 6, the unmanned forklift 2 places the cargo W in the area T of the rack 12. The vehicle control unit 30 uses the two front magnetic sensors 29 (Figure 2) of the three magnetic sensors 29 to drive the unmanned forklift 2 when it starts to enter the magnetic guidance section, and after entering the section, it uses the two front and rear magnetic sensors 29 to drive the unmanned forklift 2.

[0054] On the other hand, if the amount of lateral displacement exceeds a threshold (NO in S7), the vehicle control unit 30 determines whether the count of the switchback operation described later has reached a specified number of times (S11). Here, the count at the start of the magnetic induction switching process is zero.

[0055] If the count is not the specified number (NO in S11), the vehicle control unit 30 causes the unmanned forklift 2 to perform a switchback operation over the straight section P4-P3 of the travel path R using laser guidance (S12). That is, as shown in Figure 6B, the vehicle control unit 30 causes the unmanned forklift 2 to move backward from the confirmation position P4 to the separation position P3, and then move forward from the separation position P3 to the confirmation position P4 using laser guidance. As a result, the unmanned forklift 2 travels along the straight section P4-P3 of the travel path R while correcting its posture, and consequently, the amount of lateral displacement can be corrected. Note that the switchback operation itself is disclosed in Patent Document 4.

[0056] The vehicle control unit 30 increments the switchback operation count by 1 (S13), returns to step S6, and calculates the amount of lateral displacement again at the confirmation position P4. Therefore, the vehicle control unit 30 repeats the switchback operation until the amount of lateral displacement falls below the threshold or until the count reaches a specified number of times.

[0057] When the count of switchback operations reaches a predetermined number (YES in S11), the vehicle control unit 30 stops the unmanned forklift 2 from operation (S14). The vehicle control unit 30 may then notify the surroundings of the stoppage of operation by sound and / or light using an unillustrated notification device, and / or wirelessly notify the management device 11 of the same. This is because endlessly repeating the switchback operation would not advance the work and would be wasteful, not contributing to improved work efficiency.

[0058] As a non-exclusive example, the specified number of operations is 1. In this example, if the lateral displacement does not fall below the threshold after one switchback operation, an abnormal shutdown will occur.

[0059] As described above, in the embodiment of the present invention, even if a lateral displacement greater than the threshold occurs, the amount of lateral displacement is corrected by a switchback operation to be below the threshold, and the forklift enters the magnetic guidance section (branch passage 14, narrow passage) and travels. Therefore, the frequency of stopping the unmanned forklift 2 (abnormal stop) is lower than that described in the background art. Consequently, the switch to magnetic guidance immediately after turning with laser guidance and the travel are stable, resulting in high work continuity.

[0060] Patent Document 1 provides a switching preparation section forward of the confirmation position and corrects the amount of lateral displacement within this section. However, this makes it impossible to install racks or the like in the switching preparation section, thus reducing storage efficiency. In contrast, the embodiment of the present invention provides a separation position P3 linearly behind the confirmation position P4, beyond the turning end position P2, and corrects the lateral displacement by a switchback operation across this linear section P4-P3. Therefore, the embodiment of the present invention has the advantage of being able to correct lateral displacement without reducing storage efficiency compared to the configuration of Patent Document 1.

[0061] Furthermore, in the embodiment of the present invention, the separation position P3 is used not only for switchback operation but also for adjusting the orientation of the forks 23. Normally, the orientation of the forks 23 is adjusted at the confirmation position P4 before entering the branch passage 14. In this case, it is necessary to ensure a large main passage 13 so that the forks 23 do not interfere with equipment such as the racks 12 when rotating at the confirmation position P4. On the other hand, in the embodiment of the present invention, the separation position P3 is set behind the turning completion position P2 and away from the racks 12, etc., so there is no risk of interference with equipment inside the facility 10 when rotating the forks 23 at the separation position P3. The embodiment of the present invention also contributes to shortening the width of the main passage 13.

[0062] Furthermore, in the embodiment of the present invention, when adjusting the direction of the forks 23, the unmanned forklift 2 moves backward from the turning end position P2 to the separation position P3, adjusts the direction of the forks 23 at the separation position P3, and then moves forward from the separation position P3 to the confirmation position P4. Since this backward and forward movement of the unmanned forklift 2 is substantially a switchback operation, even if there is a lateral displacement at the end of the turning, it is reduced by this substantially switchback operation. The process then proceeds to step S7, at which point the lateral displacement is likely to be below a threshold. This leads to a further reduction in the possibility of proceeding to S12, which performs a switchback operation, and consequently, to S14, which performs an abnormal stop, and as a result contributes to improved work efficiency (shorter work cycle time).

[0063] In this embodiment, the automated guided vehicle (AGV) was an automated forklift 2, but the lateral displacement correction by the switchback operation before magnetic induction switching can also be applied to AGVs other than the automated forklift 2. [Explanation of Symbols]

[0064] 1. Cargo handling system 13 Main passage 14. Branch passages (magnetic induction sections) 16 Magnetic material 2. Unmanned forklift (an example of an automated guided vehicle) 20 car bodies 23 Forks 24. Cargo handling equipment 28 Optical Sensors 29 Magnetic Sensor 3. Control device 30 Vehicle Control Unit 300 Driving Control Unit 301 Cargo Handling Control Unit R Route P1 Turn start position P2 Turn end position P3 Separate position P4 Confirmation location P5 Switching position W luggage

Claims

1. An automated guided vehicle that travels along a travel path using laser guidance based on the output of an optical sensor and magnetic guidance based on the output of a magnetic sensor, The vehicle is equipped with a vehicle control unit that controls the operation of the automated guided vehicle, The vehicle control unit, The automated guided vehicle is rotated from the rotation start position to the rotation end position using the laser guidance. The vehicle is guided by the aforementioned laser to a confirmation position beyond the turning end position, At the aforementioned confirmation position, based on the output of the optical sensor, the amount of lateral displacement of the automated guided vehicle relative to the travel path in the magnetic induction section beyond the confirmation position is determined. If the aforementioned lateral displacement is less than or equal to the threshold, The automated guided vehicle is driven from the confirmation position to a switching position beyond the confirmation position, and at the switching position, the guidance is switched from laser guidance to magnetic guidance. If the amount of lateral displacement is greater than the threshold, The automated guided vehicle (AGV) is instructed by the laser guidance to perform a switchback maneuver, moving backward from the aforementioned confirmation position to a detached position located linearly behind the aforementioned turning end position, and then moving forward from that detached position back to the aforementioned confirmation position. Automated guided vehicle.

2. The aforementioned automated guided vehicle is an automated forklift, A fork and The system includes a cargo handling device that lifts, shifts, and rotates the forks, The vehicle control unit, Based on the work information related to cargo handling, it is determined whether the forks are facing the direction of entry for the next cargo handling operation. When the fork is facing the direction of fork entry, After turning, the automated guided vehicle is guided by the laser from the turning end position to the confirmation position. If the fork is not facing the direction of fork entry, After turning, the automated guided vehicle is moved backward from the turning end position to the separation position, the loading / unloading device directs the forks in the fork entry direction, and the automated guided vehicle is moved forward from the separation position to the confirmation position. The automated guided vehicle according to claim 1.

3. The vehicle control unit, After performing the aforementioned switchback operation a specified number of times, if the amount of lateral displacement determined at the confirmation position is greater than the threshold, the automated guided vehicle is stopped. The automated guided vehicle according to claim 1.

4. The automated guided vehicle according to claim 2, The system comprises racks provided along both sides of the aforementioned magnetic induction section, Cargo handling system.

5. A control method for driving an automated guided vehicle along a travel path using laser guidance based on the output of an optical sensor and magnetic guidance based on the output of a magnetic sensor, The automated guided vehicle is rotated from the rotation start position to the rotation end position using the laser guidance. The vehicle is guided by the aforementioned laser to a confirmation position beyond the turning end position, At the aforementioned confirmation position, based on the output of the optical sensor, the amount of lateral displacement of the automated guided vehicle relative to the travel path in the magnetic induction section beyond the confirmation position is determined. If the aforementioned lateral displacement is less than or equal to the threshold, The automated guided vehicle is driven from the confirmation position to a switching position beyond the confirmation position, and at the switching position, the guidance is switched from laser guidance to magnetic guidance. If the amount of lateral displacement is greater than the threshold, The automated guided vehicle (AGV) is instructed by the laser guidance to perform a switchback maneuver, moving backward from the aforementioned confirmation position to a detached position located linearly behind the aforementioned turning end position, and then moving forward from that detached position back to the aforementioned confirmation position. Control method.

6. The aforementioned automated guided vehicle is an automated forklift, A fork and The system includes a cargo handling device that lifts, shifts, and rotates the aforementioned forks. The control method described above is Based on the work information related to cargo handling, it is determined whether the forks are facing the direction of entry for the next cargo handling operation. When the fork is facing the direction of fork entry, After turning, the automated guided vehicle is guided by the laser from the turning end position to the confirmation position. If the fork is not facing the direction of fork entry, After turning, the automated guided vehicle is moved backward from the turning end position to the separation position, the loading / unloading device directs the forks in the fork entry direction, and the automated guided vehicle is moved forward from the separation position to the confirmation position. The control method according to claim 5.

7. The control method described above is After performing the aforementioned switchback operation a specified number of times, if the amount of lateral displacement determined at the confirmation position is greater than the threshold, the automated guided vehicle is stopped. The control method according to claim 5.

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