Travel control system

Abstract

To provide a travel control system capable of performing loading on a load carrying platform of a transport vehicle even when the transport vehicle shifts from a prescribed stop position and stops.SOLUTION: A travel control system 1 comprises: an infrastructure side detection device 7 that detects a position and an attitude of a truck 2; a shifting amount calculation unit 32 that calculates a shifting amount between a stop position and a prescribed stop position of the truck 2 on the basis of the position and the attitude of the truck 2; a travel control unit 33 for detection that controls a forklift 4 to travel to a detection position set on a side before a pallet 5 to be loaded where loading is performed on a load-carrying platform 3 on the basis of the shifting amount between the stop position and the prescribed stop position of the truck 2; a pallet detection unit 34 that detects a state of the pallet 5 to be loaded after the forklift 4 has reached the detection position; and a travel control unit 37 for movement that controls the forklift 4 to travel to a loading position where loading can be performed for an object to be loaded from the detection position on the basis of the state of the pallet 5.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a cruise control system. [Background technology]

[0002] For example, Patent Document 1 describes a travel control device. The travel control device described in Patent Document 1 includes a camera that captures an image of the front of a pallet placed on the bed of a truck to acquire image data, a laser sensor that detects the distance to the front of the pallet to acquire point cloud data, and a controller that detects the front of the pallet based on the image data from the camera and the point cloud data from the laser sensor, calculates the position and attitude of the pallet relative to the forklift based on the front of the pallet, generates a travel route to a target position where the forks of the forklift are inserted into the fork holes of the pallet based on the position and attitude of the pallet, and controls a travel motor to travel the forklift along that travel route. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2023-56669 Summary of the Invention [Problem to be solved by the invention]

[0004] However, when detecting the position and posture of a pallet placed on the bed of a truck (transport vehicle) as in the above-mentioned conventional technology, it is assumed that the truck is stopped at a specified stopping position where the pallet can be detected by the camera and laser sensor mounted on the forklift. Therefore, if the truck's stopping position deviates from the specified stopping position, the pallet placed on the bed of the truck cannot be detected, and as a result, loading and unloading onto the bed of the truck may not be possible. To avoid this problem, personnel are needed to guide the truck to stop at the specified stopping position.

[0005] An object of the present invention is to provide a travel control system that can perform loading and unloading on the platform of a transport vehicle even if the transport vehicle is stopped away from a specified stopping position. [Means for solving the problem]

[0006] (1) One aspect of the present invention is a travel control system for driving a forklift when loading and unloading onto the bed of a transport vehicle that transports cargo, the system comprising: a transport vehicle detection unit that has a sensor installed around a stopping area where the transport vehicle is stopped and that detects the transport vehicle, and that detects the position and posture of the transport vehicle; a stop position deviation calculation unit that calculates the amount of deviation between the stopping position of the transport vehicle and a predetermined specified stopping position based on the position and posture of the transport vehicle detected by the transport vehicle detection unit; a first travel control unit that controls the forklift to drive to a detection position that is set in front of a loading object on the bed where loading and unloading will be performed, in accordance with the amount of deviation between the stopping position of the transport vehicle and the specified stopping position calculated by the stop position deviation calculation unit; a loading object detection unit that detects the state of the loading object after the forklift reaches the detection position; and a second travel control unit that controls the forklift to drive from the detection position to a loading position where loading and unloading can be performed on the loading object, based on the state of the loading object detected by the loading object detection unit.

[0007] In such a travel control system, a transporter is detected by sensors installed around the stopping area where the transporter is stopped, and the position and posture of the transporter are detected. Then, based on the position and posture of the transporter, the amount of deviation between the stopping position of the transporter and a predetermined specified stopping position is calculated. Then, depending on the amount of deviation between the stopping position of the transporter and the specified stopping position, a forklift is controlled to travel to a detection position set in front of the object to be handled on the loading platform. Then, after the forklift reaches the detection position, the condition of the object to be handled is detected. Then, based on the condition of the object to be handled, the forklift is controlled to travel from the detection position to a loading position where loading can be performed on the object. In this way, the forklift travels to the detection position depending on the amount of deviation between the stopping position of the transporter and the specified stopping position. Therefore, even if the stopping position of the transporter is deviated from the specified stopping position, the condition of the object to be handled is detected at the detection position. As a result, even if the transporter is stopped away from the specified stopping position, loading can be performed on the loading platform of the transporter.

[0008] (2) In the above (1), the first travel control unit may offset the detection position in the direction in which the stopping position of the transporter is shifted from the specified stopping position by the amount of deviation between the stopping position of the transporter and the specified stopping position, and control the forklift to travel to the offset detection position.

[0009] In this configuration, the detection position is offset in the direction in which the stopping position of the transport vehicle is shifted from the specified stopping position by the amount of deviation between the stopping position of the transport vehicle and the specified stopping position, and the forklift is driven to the offset detection position, so that even if the stopping position of the transport vehicle is shifted from the specified stopping position, the forklift can reliably reach the detection position set in front of the object to be loaded.

[0010] (3) In the above (1), the first travel control unit may offset the travel route to the detection position in the direction in which the stopping position is shifted from the specified stopping position by the amount of deviation between the stopping position of the transporter and the specified stopping position, and control the forklift to travel along the offset travel route.

[0011] In this configuration, the travel route to the detection position is offset in the direction in which the stopping position is shifted from the specified stopping position by the amount of deviation between the stopping position of the transport vehicle and the specified stopping position, and the forklift is made to travel along this offset travel route, so that even if the stopping position of the transport vehicle is shifted from the specified stopping position, the forklift will reliably reach the detection position set in front of the object to be loaded.

[0012] (4) In any of (1) to (3) above, the travel control system may further include a third travel control unit that controls the forklift to travel from one side (left or right) of the transporter vehicle to the other side (left or right) depending on the amount of deviation between the stopping position of the transporter vehicle calculated by the stopping position deviation calculation unit and the specified stopping position.

[0013] In this configuration, by running the forklift from one side (left or right) of the transporter to the other side (left or right) depending on the deviation between the transporter's stopping position and the specified stopping position, even if the transporter's stopping position deviates from the specified stopping position, the forklift will move from one side (left or right) of the transporter to the other side (left or right) to avoid the transporter. Therefore, even if the transporter is stopped deviating from the specified stopping position, the same forklift can handle cargo on both the left and right sides of the transporter.

[0014] (5) In (4) above, the third travel control unit may offset the travel path from one side of the transporter vehicle to the other side of the transporter vehicle in the direction in which the stopping position is shifted from the specified stopping position by the amount of deviation between the stopping position of the transporter vehicle and the specified stopping position, and control the forklift to travel along the offset travel path.

[0015] In this configuration, the travel path from one left or right side of the transporter to the other left or right side is offset in the direction in which the stopping position is shifted from the specified stopping position by the amount of deviation between the stopping position of the transporter and the specified stopping position, and the forklift is made to travel along this offset travel path, so that even if the stopping position of the transporter is shifted from the specified stopping position, the forklift can move from one left or right side of the transporter to the other left or right side so as to reliably avoid the transporter.

[0016] (6) In any of (1) to (5) above, the travel control system may further include an obstacle detection unit that detects whether an obstacle is present in an obstacle detection area set in the travel path of the forklift, and an abnormality processing unit that controls the forklift to stop traveling when the obstacle detection unit detects the presence of an obstacle in the obstacle detection area while the forklift is traveling.

[0017] With this configuration, when the forklift detects the presence of an obstacle in an obstacle detection area set on the travel route while the forklift is traveling, the forklift is stopped, thereby preventing the forklift from interfering with the obstacle.

[0018] (7) In (6) above, the driving control system may further include a detection area correction unit that reduces the obstacle detection area in accordance with the amount of deviation between the stopping position of the transport vehicle calculated by the stopping position deviation calculation unit and the specified stopping position.

[0019] In this configuration, by reducing the obstacle detection area depending on the amount of deviation between the stopping position of the transport vehicle and the specified stopping position, when the stopping position of the transport vehicle deviates from the specified stopping position, the transport vehicle is prevented from being mistakenly detected as an obstacle even if the travel path of the transport vehicle is not offset by the amount of deviation between the stopping position of the transport vehicle and the specified stopping position. [Effects of the Invention]

[0020] According to the present invention, even if the transport vehicle is stopped at a position displaced from the specified stopping position, it is possible to perform loading and unloading onto the loading platform of the transport vehicle. [Brief explanation of the drawings]

[0021] [Figure 1] 1 is a schematic configuration diagram showing a cruise control system according to an embodiment of the present invention; [Figure 2] FIG. 2 is a block diagram of the cruise control system shown in FIG. 1. [Figure 3] 3 is a diagram showing how the position and posture of a truck are detected based on image data obtained by the infrastructure-side detection device shown in FIG. 2. FIG. [Figure 4] 3 is a flowchart showing a procedure for a detection travel control process executed by a detection travel control unit shown in FIG. 2. [Figure 5] 3 is a flowchart showing a cargo handling travel control process executed by the cargo handling travel control unit shown in FIG. 2. [Figure 6] 3 is a flowchart showing a procedure for a travel control process for travel executed by a travel control unit for travel shown in FIG. 2. [Figure 7] 3 is a flowchart showing the procedure of an abnormality process executed by an abnormality process unit shown in FIG. 2; [Figure 8] 10A and 10B are diagrams illustrating how the detection position is offset when the truck is stopped forward of the specified stopping position. [Figure 9] FIG. 10 is a diagram showing how the travel path of the truck from the left side to the right side is offset when the truck is stopped forward of the specified stopping position. [Figure 10] 5 is a flowchart showing a modified example of the procedure of the detection travel control process shown in FIG. 4. [Figure 11] FIG. 10 is a block diagram showing a cruise control system according to another embodiment of the present invention. [Figure 12] 10A and 10B are diagrams illustrating how the obstacle detection area is reduced when the truck is stopped forward of the specified stopping position. DETAILED DESCRIPTION OF THE INVENTION

[0022] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or equivalent elements are designated by the same reference numerals, and redundant description will be omitted.

[0023] Fig. 1 is a schematic diagram showing the configuration of a cruise control system according to one embodiment of the present invention, and Fig. 2 is a block diagram of the cruise control system shown in Fig. 1.

[0024] 1 and 2, a travel control system 1 of this embodiment is a system that causes an automatically operated forklift 4 to travel when the forklift 4 performs cargo handling on a loading platform 3 of a truck 2. The truck 2 is a transport vehicle that transports cargo. The truck 2 stops in a pre-designated stopping area A, for example, in a factory or a warehouse.

[0025] A plurality of pallets 5 are loaded on the loading platform 3 of the truck 2 parked in the parking area A. The pallets 5 are loading platforms for loading cargo. The pallets 5 are, for example, flat pallets made of plastic. The pallets 5 are placed side by side on both the left and right sides of the loading platform 3 of the truck 2.

[0026] The forklift 4 unloads the pallet 5 placed on the loading platform 3 of the truck 2. The forklift 4 has a pair of forks 6 on the left and right that hold the pallet 5. The pallet 5 has two pallet holes (not shown) into which the forks 6 are inserted.

[0027] The driving control system 1 includes an infrastructure-side detection device 7 installed around the stopping area A where the truck 2 is stopped, and a higher-level system management device 9 connected to the infrastructure-side detection device 7 via a wired line 8.

[0028] The infrastructure-side detection device 7 constitutes a transport vehicle detection unit that detects the position and posture of the truck 2 parked in the parking area A. The infrastructure-side detection device 7 includes a camera 10, a laser sensor 11, and a controller 12. The camera 10 and the laser sensor 11 are sensors that detect the truck 2 parked in the parking area A.

[0029] The camera 10 captures an image of an area including the parking area A, and acquires the captured image as image data.

[0030] The laser sensor 11 emits a laser toward an area including the stopping area A and receives the reflected light of the laser to measure the distance to an object present in the stopping area A and acquire point cloud data. The point cloud is a collection of laser reflection points (measurement points). For example, a LIDAR or the like is used as the laser sensor 11.

[0031] The controller 12 is configured with a CPU, RAM, ROM, an input / output interface, etc. As shown in FIG. 2 , the controller 12 has an image acquisition unit 13, a track determination unit 14, a point cloud acquisition unit 15, a position and orientation calculation unit 16, and an information notification unit 17.

[0032] The image acquisition unit 13 acquires image data from the camera 10. The truck determination unit 14 determines whether a truck 2 is present in the stopping area A based on the image data acquired by the image acquisition unit 13. The truck determination unit 14 determines whether a truck 2 is captured in the image data, for example, using machine learning. For example, in the image data Di shown in FIG. 3(a), the area within the frame line W1 is extracted as the truck 2.

[0033] The point cloud acquisition unit 15 acquires only the point cloud data of the loading platform 3 of the truck 2 that is determined by the truck determination unit 14 to be present in the stopping area A from the point cloud data of the laser sensor 11. For example, in the image data Di shown in FIG. 3(b), the point cloud data within the frame line W2 is acquired as the point cloud data of the loading platform 3.

[0034] The position and orientation calculation unit 16 calculates the position and orientation of the truck 2 parked in the parking area A based on the point cloud data of the loading platform 3 acquired by the point cloud acquisition unit 15. The position and orientation calculation unit 16, for example, extracts the edge of the loading platform 3 from the point cloud data of the loading platform 3, and calculates the position of the truck 2 from the edge of the loading platform 3. In addition, the position and orientation calculation unit 16, for example, extracts the plane of the loading platform 3 from the point cloud data of the loading platform 3, and calculates the orientation of the truck 2 from the plane of the loading platform 3.

[0035] The information notification unit 17 notifies the higher-level system management device 9 of the information on the position and orientation of the truck 2 calculated by the position and orientation calculation unit 16 via the wired line 8 .

[0036] As shown in FIG. 2, the upper system management device 9 includes a controller 18 and a communication device 19.

[0037] The controller 18 is composed of a CPU, RAM, ROM, an input / output interface, etc. The controller 18 has an information relay unit 20. The information relay unit 20 outputs the information on the position and posture of the truck 2 sent from the infrastructure-side detection device 7 to a communication device 19. The communication device 19 transmits the information on the position and posture of the truck 2 to the forklift 4 via wireless communication.

[0038] As shown in FIG. 2, the travel control system 1 includes a communication device 21 mounted on the forklift 4, a laser sensor 22 for self-position estimation, a map memory unit 23, a laser sensor 24 for pallet detection, a laser sensor 25 for obstacle detection, a travel drive unit 26, a loading drive unit 27, an alarm 28, and a controller 29.

[0039] The communication device 21 performs wireless communication with the communication device 19 of the higher-level system management device 9. The communication device 21 receives information on the position and attitude of the truck 2 transmitted from the communication device 19.

[0040] The laser sensor 22 emits a laser beam toward the periphery of the forklift 4 and receives reflected light of the laser to measure the distance to objects present around the forklift 4 and acquire point cloud data. As the laser sensor 22, for example, a LIDAR or the like is used.

[0041] The map storage unit 23 stores map data of the area in which the forklift 4 travels. The map data includes buildings, pillars, shelves, walls, etc. The map data is created in advance using the laser sensor 22.

[0042] The laser sensor 24 emits a laser beam toward the side of the forklift 4 and receives the reflected laser light, thereby measuring the distance to the pallet 5 located on the side of the forklift 4 and acquiring point cloud data. The laser sensors 24 are disposed on both the left and right sides of the forklift 4. As the laser sensors 24, for example, LIDAR or the like is used.

[0043] The number of laser sensors 25 is, for example, two. The laser sensors 25 emit lasers in front and behind the forklift 4 and receive reflected laser light to detect obstacles present in the traveling direction of the forklift 4. As the laser sensors 25, for example, LIDAR or the like is used.

[0044] Although not specifically shown, the traveling drive unit 26 has a traveling motor that causes the forklift 4 to travel and a steering motor that steers the forklift 4.

[0045] Although not specifically shown, the cargo handling drive unit 27 has a lifting drive system including a lift cylinder that raises and lowers the forks 6, and a tilting drive system including a tilt cylinder that tilts the forks 6.

[0046] The alarm 28 issues an alarm by sounding an alarm, displaying an alarm, or the like when the forklift 4 is brought to an emergency stop.

[0047] The controller 29 is composed of a CPU, RAM, ROM, an input / output interface, etc. The controller 29 has a self-position estimation unit 30, an information acquisition unit 31, a deviation amount calculation unit 32, a detection travel control unit 33, a pallet detection unit 34, a cargo handling travel control unit 35, a cargo handling control unit 36, a transfer travel control unit 37, an obstacle determination unit 38, and an abnormality processing unit 39.

[0048] The self-position estimation unit 30 estimates the self-position of the forklift 4 based on the point cloud data of the laser sensor 22 and the map data stored in the map storage unit 23. Specifically, the self-position estimation unit 30 uses, for example, a SLAM (simultaneous localization and mapping) method to match the point cloud data of the laser sensor 22 with map data and estimate the self-position of the forklift 4. SLAM is a self-position estimation technology that estimates the self-position using sensor data and map data.

[0049] The information acquisition unit 31 acquires information on the position and attitude of the truck 2 received by the communication device 21 .

[0050] The deviation amount calculation unit 32 calculates the deviation amount M (see FIGS. 8 and 9) between the stopping position of the truck 2 and a predetermined specified stopping position Pt, based on the position and posture of the truck 2 acquired by the information acquisition unit 31. The specified stopping position Pt is the position where the truck 2 should originally stop in the stopping area A, and is determined by, for example, a stop line.

[0051] The deviation amount calculation unit 32 cooperates with the information relay unit 20, communication device 19, communication device 21 and information acquisition unit 31 of the higher-level system management device 9 to constitute a stop position deviation calculation unit that calculates the deviation amount M between the stopping position of the truck 2 and a predetermined specified stopping position Pt based on the position and posture of the truck 2 detected by the infrastructure side detection device 7.

[0052] The detection travel control unit 33 controls the travel drive unit 26 to travel the forklift 4 to a detection position D (see FIG. 8) where the laser sensor 24 detects the pallet 5 to be loaded, in accordance with the deviation M between the stop position of the truck 2 and the specified stop position Pt calculated by the deviation amount calculation unit 32. The detection position D is a position set so that the laser sensor 24 faces the front of the pallet 5 to be loaded, with the fore-and-aft direction of the forklift 4 parallel to the fore-and-aft direction of the truck 2. In other words, the detection position D is a position set on the near side of the pallet 5 to be loaded.

[0053] The detection travel control unit 33 constitutes a first travel control unit that controls the forklift 4 to travel to a detection position D that is set in front of the loading object on the loading platform 3 of the truck 2, depending on the amount of deviation M between the stopping position of the truck 2 calculated by the stopping position deviation calculation unit and the specified stopping position Pt.

[0054] The detection travel control unit 33 offsets the detection position D in the direction in which the stopping position is shifted from the specified stopping position Pt by the amount of deviation M between the stopping position of the truck 2 and the specified stopping position Pt, and controls the travel drive unit 26 to travel the forklift 4 to the offset detection position D.

[0055] 4 is a flowchart showing the procedure of the detection travel control process executed by the detection travel control unit 33. When this process starts, the forklift 4 is stopped at the loading start position where loading operation is to be started.

[0056] 4, the detection travel control unit 33 offsets the detection position D by the amount of deviation M between the stop position of the truck 2 and the specified stop position Pt, calculated by the deviation amount calculation unit 32 (step S101). When the stop position of the truck 2 is deviated forward from the specified stop position Pt, the detection travel control unit 33 offsets the detection position D forward by the amount of deviation M (see FIGS. 8(a) and 8(c)). When the stop position of the truck 2 is deviated backward from the specified stop position Pt, the detection travel control unit 33 offsets the detection position D backward by the amount of deviation M.

[0057] Next, the detection travel control unit 33 generates a travel route from the loading start position to the offset detection position D (Step S102). Next, the detection travel control unit 33 controls the travel drive unit 26 to cause the forklift 4 to travel along the travel route (Step S103).

[0058] Next, the detection travel control unit 33 determines whether the forklift 4 has reached the detection position D based on the self-position of the forklift 4 estimated by the self-position estimation unit 30 (step S104).

[0059] If the detection travel control unit 33 determines that the forklift 4 has not reached the detection position D, it executes the above-mentioned step S103 again. If the detection travel control unit 33 determines that the forklift 4 has reached the detection position D, it controls the travel drive unit 26 to stop the travel of the forklift 4 (step S105).

[0060] Returning to FIG. 2 , after the forklift 4 reaches detection position D, the pallet detection unit 34 detects the position and posture of the pallet 5 to be handled based on the point cloud data of the laser sensor 24. The position and posture of the pallet 5 to be handled corresponds to the state of the pallet 5 to be handled. The pallet detection unit 34 cooperates with the laser sensor 24 to constitute a handling object detection unit that detects the state of the handling object after the forklift 4 reaches detection position D.

[0061] The cargo handling travel control unit 35 controls the travel drive unit 26 to cause the forklift 4 to travel from the detection position D to a loading position where loading can be performed on the pallet 5, based on the position and posture of the pallet 5 to be handled that is detected by the pallet detection unit 34. The loading position is a position where the forks 6 of the forklift 4 can be inserted into the pallet holes (described above) of the pallet 5.

[0062] The cargo handling travel control unit 35 constitutes a second travel control unit that controls the forklift 4 to travel from the detection position D to a cargo handling position where cargo can be handled on the cargo object based on the state of the cargo object detected by the cargo object detection unit.

[0063] 5 is a flowchart showing the procedure of the cargo handling travel control process executed by the cargo handling travel control unit 35. When this process starts, the forklift 4 is stopped at the detection position D.

[0064] 5, the cargo handling travel control unit 35 generates a travel route from the detection position D to the cargo handling position based on the position and posture of the pallet 5 to be handled detected by the pallet detection unit 34 (step S111). The cargo handling travel control unit 35 generates a travel route such that the forklift 4 moves straight backward from the detection position D, then moves forward to the cargo handling position and turns.

[0065] Next, the cargo handling travel control unit 35 controls the travel drive unit 26 to cause the forklift 4 to travel along the travel route (step S112). Next, the cargo handling travel control unit 35 determines whether the forklift 4 has reached the cargo handling position based on the self-position of the forklift 4 estimated by the self-position estimation unit 30 (step S113).

[0066] If the cargo handling travel control unit 35 determines that the forklift 4 has not reached the cargo handling position, it executes the above-mentioned step S112 again. If the cargo handling travel control unit 35 determines that the forklift 4 has reached the cargo handling position, it controls the travel drive unit 26 to stop the travel of the forklift 4 (step S114).

[0067] Returning to Figure 2, after the forklift 4 reaches the loading position, the cargo handling control unit 36 ​​controls the traveling drive unit 26 and the cargo handling drive unit 27 so that the forklift 4 performs loading on the pallet 5 that is the loading target. Specifically, the cargo handling control unit 36 ​​controls the traveling drive unit 26 and the cargo handling drive unit 27 so that the forks 6 are inserted into the pallet holes of the pallet 5 to lift the pallet 5, and then controls the traveling drive unit 26 so that the forklift 4 travels to a specified location.

[0068] The transfer travel control unit 37 controls the travel drive unit 26 to cause the forklift 4 to travel from one left or right side of the truck 2 to the other left or right side, in accordance with the deviation amount M between the stopping position of the truck 2 and the specified stopping position Pt calculated by the deviation amount calculation unit 32. The transfer travel control unit 37 constitutes a third travel control unit that controls the forklift 4 to travel from one left or right side of the truck 2 to the other left or right side, in accordance with the deviation amount M between the stopping position of the truck 2 and the specified stopping position Pt calculated by the stop position deviation calculation unit.

[0069] The mobile travel control unit 37 offsets the travel path from one left or right side of the truck 2 to the other left or right side by the amount of deviation M between the stopping position of the truck 2 and the specified stopping position Pt in the direction in which the stopping position is shifted from the specified stopping position Pt, and controls the travel drive unit 26 to make the forklift 4 travel along the offset travel path.

[0070] 6 is a flowchart showing the procedure of the transfer travel control process executed by the transfer travel control unit 37. When this process starts, the forklift 4 is stopped at a movement start position on either the left or right side of the truck 2.

[0071] 6, the transfer travel control unit 37 generates a travel route from a movement start position on one of the left and right sides of the truck 2 to a movement end position on the other of the left and right sides of the truck 2 (step S121). The movement start position on one of the left and right sides of the truck 2 is a position where the loading operation ends on one of the left and right sides of the truck 2. The movement end position on the other of the left and right sides of the truck 2 is a position where the loading operation starts on the other of the left and right sides of the truck 2.

[0072] At this time, the transfer travel control unit 37 generates a travel route from the movement start position on one of the left and right sides of the truck 2, passing in front of the truck 2, to the movement end position on the other of the left and right sides of the truck 2 (see FIG. 9). Note that the travel route from the movement start position on one of the left and right sides of the truck 2 to the movement end position on the other of the left and right sides of the truck 2 may be a route that passes behind the truck 2.

[0073] Next, the transfer travel control unit 37 offsets the travel route by the deviation amount M between the stop position of the truck 2 and the specified stop position Pt, calculated by the deviation amount calculation unit 32 (step S122). When the stop position of the truck 2 is deviated forward from the specified stop position Pt, the transfer travel control unit 37 offsets the travel route forward by the deviation amount M (see FIGS. 9(a) and 9(c)). When the stop position of the truck 2 is deviated backward from the specified stop position Pt, the transfer travel control unit 37 offsets the travel route backward by the deviation amount M.

[0074] Next, the travel control unit 37 for transportation controls the travel drive unit 26 to cause the forklift 4 to travel along the travel route (step S123). Next, the travel control unit 37 for transportation determines whether the forklift 4 has reached the travel end position on the other left or right side of the truck 2, based on the self-position of the forklift 4 estimated by the self-position estimation unit 30 (step S124).

[0075] If the transfer travel control unit 37 determines that the forklift 4 has not reached the travel end position on the other left or right side of the truck 2, it executes the above-mentioned step S123 again. If the transfer travel control unit 37 determines that the forklift 4 has reached the travel end position on the other left or right side of the truck 2, it controls the travel drive unit 26 to stop the travel of the forklift 4 (step S125).

[0076] Returning to FIG. 2, the obstacle determining unit 38 determines whether or not an obstacle exists in an obstacle detection area E (see FIG. 9) that is virtually set on the travel path of the forklift 4, based on the point cloud data of the laser sensor 25.

[0077] The obstacle detection area E has, for example, a rectangular shape. The obstacle detection area E has dimensions that make it larger than the forklift 4 by the same distance in the front-to-rear and left-to-right directions. A normal value for the obstacle detection area E is set in advance. The shape of the obstacle detection area E is not limited to a rectangular shape and may be a circle, etc. Obstacles include trucks 2.

[0078] The obstacle determining unit 38 cooperates with the laser sensor 25 to form an obstacle detecting unit that detects whether or not an obstacle exists in an obstacle detection area E set on the travel route of the forklift 4.

[0079] When the obstacle determination unit 38 determines that an obstacle is present in the obstacle detection area E while the forklift 4 is traveling, the abnormality processing unit 39 controls the traveling drive unit 26 to stop the forklift 4 from traveling.

[0080] 7 is a flowchart showing the procedure of the abnormality processing executed by the abnormality processing unit 39. This processing is executed while the forklift 4 is traveling.

[0081] 7, the abnormality processing unit 39 determines whether the obstacle determination unit 38 has determined that an obstacle exists in the obstacle detection area E (step S131). When the abnormality processing unit 39 determines that an obstacle exists in the obstacle detection area E, it controls the alarm 28 to issue an alarm (step S132). In addition, the abnormality processing unit 39 controls the traveling drive unit 26 to stop the traveling of the forklift 4 (step S133).

[0082] In the above-described driving control system 1, as shown in FIG. 8(a), when the truck 2 is stopped exactly at the specified stopping position Pt, when the forklift 4 travels to the detection position D, the pallet 5 to be loaded placed on the loading platform 3 of the truck 2 is detected by the laser sensor 24.

[0083] However, as shown in Figure 8(b), if the truck 2 is stopped significantly ahead of the specified stopping position Pt, even if the forklift 4 travels to detection position D, the pallet 5 to be loaded is not present at a position on the bed 3 of the truck 2 corresponding to detection position D, and therefore the laser sensor 24 cannot detect the pallet 5 to be loaded.

[0084] Therefore, the position and posture of the truck 2 are detected by an infrastructure-side detection device 7 installed around the truck 2. Then, information on the position and posture of the truck 2 is sent to the forklift 4 via a host system management device 9.

[0085] Then, the forklift 4 calculates the amount of deviation M between the stopping position of the truck 2 and the specified stopping position Pt based on the position and posture of the truck 2. Then, the detection position D is offset by the amount of deviation M between the stopping position of the truck 2 and the specified stopping position Pt.

[0086] Therefore, when the truck 2 is stopped at a position shifted forward from the specified stopping position Pt, the detection position D is offset forward by the amount of deviation M between the stopping position of the truck 2 and the specified stopping position Pt, as shown in FIG. 8(c). The forklift 4 then travels to the offset detection position D. Therefore, the pallet 5 to be handled, which is placed on the loading platform 3 of the truck 2, can be detected by the laser sensor 24.

[0087] When the pallet 5 to be unloaded is detected, a travel route from the detection position D to the unloading position is generated based on the position and posture of the pallet 5 to be unloaded. Then, the forklift 4 travels to the unloading position along the travel route. The forklift 4 then unloads the pallet 5 to be unloaded. The forklift 4 then travels to the specified location, and the pallet 5 to be unloaded is transported to the specified location.

[0088] When the unloading of the pallet 5 placed on the left side of the loading platform 3 of the truck 2 is completed, the unloading of the pallet 5 placed on the right side of the loading platform 3 of the truck 2 is carried out. For this purpose, the forklift 4 crosses in front of the truck 2 and moves from the left side to the right side of the truck 2. When the forklift 4 crosses in front of the truck 2, a travel path for the forklift 4 is generated so that the obstacle detection area E avoids the truck 2.

[0089] At this time, as shown in FIG. 9(a), if the truck 2 stops exactly at the specified stopping position Pt, the obstacle detection area E set on the travel route R will not interfere with the truck 2.

[0090] However, as shown in FIG. 9(b), if truck 2 is stopped at a position significantly shifted forward of truck 2 relative to specified stopping position Pt, obstacle detection area E set on travel route R will interfere with truck 2.

[0091] 9(c), the travel route R is offset forward by the amount of deviation M between the stopping position of the truck 2 and the specified stopping position Pt. Therefore, when the forklift 4 crosses in front of the truck 2, the obstacle detection area E is offset forward by the amount of deviation between the stopping position of the truck 2 and the specified stopping position Pt. This prevents the obstacle detection area E set on the travel route R from interfering with the truck 2.

[0092] As described above, in this embodiment, the truck 2 is detected by the camera 10 and the laser sensor 11 installed around the stopping area A where the truck 2 is stopped, and the position and posture of the truck 2 are detected. Then, based on the position and posture of the truck 2, the deviation amount M between the stopping position of the truck 2 and the predetermined specified stopping position Pt is calculated. Then, in accordance with the deviation amount M between the stopping position of the truck 2 and the specified stopping position Pt, the forklift 4 is controlled to travel to a detection position D set in front of the pallet 5 to be unloaded on the loading platform 3 of the truck 2. Then, after the forklift 4 reaches the detection position D, the condition of the pallet 5 to be unloaded is detected. Then, based on the condition of the pallet 5 to be unloaded, the forklift 4 is controlled to travel from the detection position D to a loading position where loading can be performed on the pallet 5 to be unloaded. In this way, the forklift 4 travels to the detection position D in accordance with the deviation amount M between the stopping position of the truck 2 and the specified stopping position Pt. Therefore, even if the stopping position of the truck 2 is shifted from the specified stopping position Pt, the state of the pallet 5 to be unloaded can be detected at the detection position D. As a result, even if the truck 2 is stopped at a position shifted from the specified stopping position Pt, unloading can be performed on the loading platform 3 of the truck 2. As a result, there is no need for personnel to guide the truck 2 to stop at the specified stopping position Pt, which makes it possible to reduce the number of personnel involved in unloading work.

[0093] Furthermore, in this embodiment, the detection position D is offset in the direction in which the stopping position is shifted from the specified stopping position Pt by the amount of deviation M between the stopping position of the truck 2 and the specified stopping position Pt, and the forklift 4 is driven to the offset detection position D. This ensures that even if the stopping position of the truck 2 is shifted from the specified stopping position Pt, the forklift 4 will reliably reach the detection position D, which is set in front of the pallet 5 to be loaded.

[0094] Furthermore, in this embodiment, the forklift 4 travels from one left or right side of the truck 2 to the other left or right side according to the deviation M between the stopping position of the truck 2 and the specified stopping position Pt, so that even if the stopping position of the truck 2 deviates from the specified stopping position Pt, the forklift 4 moves from one left or right side of the truck 2 to the other left or right side to avoid the truck 2. Therefore, even if the truck 2 is stopped deviated from the specified stopping position Pt, the same forklift 4 can handle cargo on the loading platform 3 on both the left and right sides of the truck 2.

[0095] In addition, in this embodiment, the travel route from one left or right side of truck 2 to the other left or right side is offset in the direction in which the stopping position is shifted from the specified stopping position Pt by the amount of deviation M between the stopping position of truck 2 and the specified stopping position Pt, and by making forklift 4 travel along this offset travel route, even if the stopping position of truck 2 is shifted from the specified stopping position Pt, forklift 4 moves from one left or right side of truck 2 to the other left or right side so as to reliably avoid truck 2.

[0096] In addition, in this embodiment, when the forklift 4 is traveling and an obstacle is detected in the obstacle detection area E set on the travel route, the forklift 4 is stopped from traveling, thereby preventing the forklift 4 from interfering with the obstacle.

[0097] In addition, in this embodiment, the travel path from one side of truck 2 to the other side is offset so that obstacle detection area E does not interfere with truck 2, thereby preventing truck 2 from being mistakenly detected as an obstacle when the stopping position of truck 2 is shifted from the specified stopping position Pt.

[0098] FIG. 10 is a flowchart showing a modified example of the procedure of the detection travel control process executed by the detection travel control unit 33, and corresponds to FIG.

[0099] 10, the detection travel control unit 33 generates a travel route from the loading start position to the detection position D (step S151). Next, the detection travel control unit 33 offsets the travel route by the deviation amount M between the stop position of the truck 2 and the specified stop position Pt calculated by the deviation amount calculation unit 32 (step S152).

[0100] When the stopping position of the truck 2 is deviated forward from the specified stopping position Pt, the detection traveling control unit 33 offsets the traveling route forward by the deviation amount M. When the stopping position of the truck 2 is deviated backward from the specified stopping position Pt, the detection traveling control unit 33 offsets the traveling route backward by the deviation amount M.

[0101] Next, the detection travel control unit 33 controls the travel drive unit 26 to cause the forklift 4 to travel along the offset travel path (step S153). Next, the detection travel control unit 33 executes steps S104 and S105, similar to FIG. 4.

[0102] In such a modified example, the travel route to the detection position D is offset in the direction in which the stopping position is shifted from the specified stopping position Pt by the amount of deviation M between the stopping position of the truck 2 and the specified stopping position Pt, and the forklift 4 is made to travel along this offset travel route, so that even if the stopping position of the truck 2 is shifted from the specified stopping position Pt, the forklift 4 will reliably reach the detection position D, which is set in front of the pallet 5 to be loaded.

[0103] 11 is a block diagram showing a cruise control system according to another embodiment of the present invention. In FIG. 11, a cruise control system 1A of this embodiment includes a controller 29A instead of the controller 29 in the above embodiment.

[0104] The controller 29A has a detection area correction unit 40 in addition to the above-mentioned self-position estimation unit 30, information acquisition unit 31, deviation amount calculation unit 32, detection driving control unit 33, pallet detection unit 34, cargo handling driving control unit 35, cargo handling control unit 36, transfer driving control unit 37, obstacle determination unit 38 and abnormality processing unit 39.

[0105] The detection area correction unit 40 reduces the obstacle detection area E in accordance with the deviation M between the stopping position of the truck 2 and the specified stopping position Pt calculated by the deviation amount calculation unit 32. The detection area correction unit 40 reduces the obstacle detection area E continuously or stepwise from the normal value (described above) in accordance with, for example, the deviation M between the stopping position of the truck 2 and the specified stopping position Pt.

[0106] At this time, the width of the obstacle detection area E is reduced from its normal value (see FIGS. 12(a) and 12(b)). The width of the obstacle detection area E is the dimension in the direction corresponding to the vehicle width (left-right direction) of the forklift 4. Note that the obstacle detection area E may be reduced in any direction, including the front-rear and left-right directions.

[0107] When the forklift 4 passes in front of the truck 2 and moves from one side (left or right) of the truck 2 to the other side (left or right), the detection area correction unit 40 reduces the obstacle detection area E when the stopping position of the truck 2 deviates forward from the specified stopping position Pt. When the forklift 4 passes behind the truck 2 and moves from one side (left or right) of the truck 2 to the other side (left or right), the detection area correction unit 40 reduces the obstacle detection area E when the stopping position of the truck 2 deviates rearward from the specified stopping position Pt.

[0108] 12, when truck 2 is stopped at a position shifted forward of truck 2 with respect to specified stopping position Pt, obstacle detection area E is reduced by an amount corresponding to the amount of deviation M between the stopping position of truck 2 and specified stopping position Pt. Therefore, even if the traveling route of truck 2 is not offset by the amount of deviation M between the stopping position of truck 2 and specified stopping position Pt, the obstacle detection area E set on traveling route R is prevented from interfering with truck 2.

[0109] In this embodiment, by reducing the obstacle detection area E according to the deviation M between the stopping position of truck 2 and the specified stopping position Pt, when the stopping position of truck 2 deviates from the specified stopping position Pt, truck 2 is prevented from being mistakenly detected as an obstacle even if the traveling path of truck 2 is not offset by the deviation M between the stopping position of truck 2 and the specified stopping position Pt.

[0110] The present invention is not limited to the above embodiment. For example, in the above embodiment, the travel path from the detection position D to the loading position is not offset, but the present invention is not particularly limited to this embodiment. After the position and posture of the pallet 5 to be loaded is detected, the travel path from the detection position D to the loading position may be offset in accordance with the deviation M between the stopping position of the truck 2 and the specified stopping position Pt. For example, when the forklift 4 turns while moving forward toward the loading position, the travel path to the loading position may be offset by an amount corresponding to the deviation M between the stopping position of the truck 2 and the specified stopping position Pt. In this case, it is possible to deal with restrictions, etc., that exist behind the detection position D.

[0111] Furthermore, in the above embodiment, the camera 10 and laser sensor 11 of the infrastructure-side detection device 7 are used to detect the position and posture of the truck 2 parked in the parking area A, but this is not particularly limited to such an embodiment. For example, the position and posture of the truck 2 may be detected based on point cloud data of the laser sensor 11 without using the camera 10, or the position and posture of the truck 2 may be detected based on image data of the camera 10 without using the laser sensor 11. In this case, the number of sensors mounted on the infrastructure-side detection device 7 is reduced, thereby enabling cost reduction.

[0112] In the above embodiment, the position and posture of the pallet 5 is detected using the laser sensor 24 that emits a laser beam toward the side of the forklift 4 while the forklift 4 is facing sideways relative to the pallet 5 placed on the loading platform 3 of the truck 2, but the present invention is not limited to this particular form. The position and posture of the pallet 5 may also be detected using a laser sensor that emits a laser beam toward the front of the forklift 4 while the forklift 4 is facing forward relative to the pallet 5 placed on the loading platform 3 of the truck 2.

[0113] In addition, in the above embodiment, the controller 29, 29A of the forklift 4 has the deviation amount calculation unit 32, but this is not limited to this particular form, and the function of the deviation amount calculation unit 32 may be provided in the controller 18 of the higher-level system management device 9 or the controller 12 of the infrastructure-side detection device 7.

[0114] Furthermore, in the above embodiment, the pallet 5 placed on the bed 3 of the truck 2 is unloaded, but this is not a particular limitation, and the pallet 5 may be loaded onto the bed 3 of the truck 2. In this case, if a pallet 5 has already been placed on the bed 3 of the truck 2, the loading target is the loading surface on the bed 3 next to the existing pallet 5. If a pallet 5 has not yet been placed on the bed 3 of the truck 2, the loading target is the loading surface at the front end or rear end of the bed 3.

[0115] In the above embodiment, the forklift 4 handles the loading onto the loading platform 3 of the truck 2, but the loading is not limited to the truck 2, and may be carried out onto the loading platform of a transport vehicle that transports luggage, for example. In this case, the transport vehicle is a transport vehicle that transports luggage. [Explanation of symbols]

[0116] 1, 1A... Travel control system, 2... Truck (transport vehicle), 3... Platform, 4... Forklift, 5... Pallet (loading object), 7... Infrastructure side detection device (transport vehicle detection unit), 19... Communication device (stopping position deviation calculation unit), 20... Information relay unit (stopping position deviation calculation unit), 21... Communication device (stopping position deviation calculation unit), 24... Laser sensor (loading object detection unit), 25... Laser sensor (obstacle detection unit), 31... Information acquisition unit (stopping position deviation calculation unit), 32 ...deviation amount calculation unit (stop position deviation calculation unit), 33...detection driving control unit (first driving control unit), 34...pallet detection unit (loading object detection unit), 35...loading driving control unit (second driving control unit), 37...transport driving control unit (third driving control unit), 38...obstacle determination unit (obstacle detection unit), 39...abnormality processing unit, 40...detection area correction unit, A...stopping area, D...detection position, E...obstacle detection area, Pt...specified stopping position, M...deviation amount, R...driving route.

Claims

1. A travel control system for driving a forklift when the forklift handles cargo on a loading platform of a transport vehicle for transporting cargo, comprising: a vehicle detection unit that is installed around a parking area where the vehicle is parked and has a sensor that detects the vehicle and detects the position and posture of the vehicle; a stop position deviation calculation unit that calculates a deviation amount between a stop position of the transported vehicle and a predetermined specified stop position based on the position and posture of the transported vehicle detected by the transported vehicle detection unit; a first travel control unit that controls the forklift to travel to a detection position that is set in front of a loading target on the loading platform, according to the amount of deviation between the stopping position of the transporter and the specified stopping position calculated by the stopping position deviation calculation unit; and a load object detection unit that detects a state of the load object after the forklift reaches the detection position; and a second travel control unit that controls the forklift to travel from the detection position to a loading position where loading can be performed on the loading object based on the state of the loading object detected by the loading object detection unit.

2. 2. The travel control system according to claim 1, wherein the first travel control unit offsets the detection position in a direction in which the stop position of the transporter is shifted from the specified stop position by an amount corresponding to a deviation between the stop position of the transporter and the specified stop position, and controls the forklift to travel to the offset detection position.

3. 2. The travel control system according to claim 1, wherein the first travel control unit offsets a travel path to the detection position in a direction in which the stop position of the transporter is shifted from the specified stop position by an amount corresponding to a deviation between the stop position of the transporter and the specified stop position, and controls the forklift to travel along the offset travel path.

4. 2. The travel control system according to claim 1, further comprising a third travel control unit that controls the forklift to travel from one left or right side of the transporter to the other left or right side in accordance with the amount of deviation between the stopping position of the transporter calculated by the stopping position deviation calculation unit and the specified stopping position.

5. 5. The travel control system according to claim 4, wherein the third travel control unit offsets a travel path from one left or right side of the transporter to the other left or right side of the transporter in a direction in which the stopping position is shifted from the specified stopping position by an amount corresponding to a deviation between the stopping position of the transporter and the specified stopping position, and controls the forklift to travel along the offset travel path.

6. an obstacle detection unit that detects whether an obstacle exists in an obstacle detection area set on a travel route of the forklift; 2. The travel control system according to claim 1, further comprising an abnormality processing unit that controls the forklift to stop traveling when the obstacle detection unit detects the presence of the obstacle in the obstacle detection area while the forklift is traveling.

7. 7. The driving control system according to claim 6, further comprising a detection area correction unit that reduces the obstacle detection area in accordance with the amount of deviation between the stop position of the transporter calculated by the stop position deviation calculation unit and the specified stop position.

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