Carriage, connecting part, distance specifying method, and distance specifying program

Abstract

To provide a transport vehicle capable of adjusting a cargo loading position afterward even if a mobile shelf, a truck, or the like deviates from a predetermined position.SOLUTION: A transport vehicle 1 includes: fork prongs 16; a point group acquisition unit 22 that acquires a point group PG by horizontal irradiation with a laser; and a distance determination unit that determines a distance in a lateral direction between a cargo loaded on the fork prongs 16 and an object adjacent to a cargo loading position based on the acquired point group PG. The point group acquisition unit 22 is arranged at a position allowing for irradiating the cargo loaded on the fork prongs 16 and the cargo loading position with the laser.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a transport vehicle, a connecting portion, a distance specifying method, and a distance specifying program.

Background Art

[0002] Conventionally, as shown in Patent Document 1, there is an automated guided vehicle that autonomously travels and performs loading and unloading operations. The automated guided vehicle disclosed in Patent Document 1 includes a fork, a lifting device for lifting and lowering the fork, and a laser scanner for detecting the position of the vehicle itself. The automated guided vehicle is configured to move to a predetermined loading and unloading position while detecting its own position, and perform loading and unloading operations by lifting and lowering the fork.

[0003] By the way, as disclosed in Patent Document 1, the automated guided vehicle may perform loading and unloading operations on a movable shelf. The movable shelf moves unlike a fixed shelf, but may deviate from a predetermined moving position during this movement. Then, a deviation occurs between the predetermined loading and unloading position and the movable shelf, but the automated guided vehicle system of Patent Document 1 does not consider this deviation. Also, when performing loading and unloading operations on a truck parked at a predetermined position, the truck may deviate from the predetermined standby position, and in this case as well, a deviation occurs from the predetermined loading and unloading position. Assuming that the loading and unloading position is determined assuming that the movable shelf or the truck deviates, there is a problem that it is impossible to load the goods tightly between the goods. In order to solve this problem, it is preferable to adjust the cargo loading position after the automated guided vehicle arrives at the predetermined loading and unloading position, but it is not easy and difficult to recognize how much the movable shelf, the truck, etc. deviate from the predetermined position.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Therefore, the problem to be solved by the present invention is to provide a carrier capable of correcting the cargo loading position later even if a movable shelf, a truck, or the like is displaced from a predetermined position.

Means for Solving the Problem

[0006] In order to solve the above problems, the carrier according to the present invention includes: a cargo loading section; a point cloud acquisition section that is disposed at a position where a laser can be irradiated onto the cargo loaded on the cargo loading section, the cargo loading position, and irradiates the laser horizontally to acquire a point cloud; a distance specifying section that specifies a left-right direction distance between the cargo loaded on the cargo loading section and an object adjacent to the cargo loading position based on the acquired point cloud.

[0007] The above carrier is, for example, the carrier is a forklift, includes a backrest, and the point cloud acquisition section is provided on the backrest.

[0008] The above carrier preferably further includes a connecting section that is connected to the backrest and the point cloud acquisition section and arranges the point cloud acquisition section diagonally behind either the left or right end of the backrest in a plan view.

[0009] The above carrier preferably the distance specifying section further specifies a front-rear direction distance between the cargo loaded on the cargo loading section and an object adjacent to the cargo loading position based on the acquired point cloud.

[0010] In order to solve the above problems, the distance specifying method according to the present invention is A method for specifying the lateral distance between a load loaded on the load-carrying part of a transport vehicle and an object adjacent to the load-carrying position, comprising: a step of horizontally irradiating the load loaded on the load-carrying part and the object adjacent to the load-carrying position with a laser to obtain a point cloud; and a step of specifying the lateral distance between the load loaded on the load-carrying part and the object adjacent to the load-carrying position based on the obtained point cloud.

[0011] In order to solve the above problems, the distance specifying method according to the present invention is as follows. A method for specifying the longitudinal distance between a load loaded on the load-carrying part of a transport vehicle and an object adjacent to the load-carrying position, comprising: a step of horizontally irradiating the load loaded on the load-carrying part and the object adjacent to the load-carrying position with a laser to obtain a point cloud; and a step of specifying the longitudinal distance between the load loaded on the load-carrying part and the object adjacent to the load-carrying position based on the obtained point cloud.

[0012] In order to solve the above problems, the distance specifying program according to the present invention is as follows. A computer of a transport vehicle configured to be able to horizontally irradiate a load-carrying part, a load loaded on the load-carrying part, and a load-carrying position with a laser, and having a point cloud acquisition unit for acquiring a point cloud, and a computer, is caused to execute a step of specifying the distance between the load loaded on the load-carrying part and an object adjacent to the load-carrying position based on the acquired point cloud.

[0013] In order to solve the above problems, the connecting part according to the present invention is as follows. A connecting part provided on a transport vehicle configured to be able to horizontally irradiate a load-carrying part, a load loaded on the load-carrying part, and a load-carrying position with a laser, and having a point cloud acquisition unit for acquiring a point cloud, and a distance specifying unit for specifying the lateral distance between the load loaded on the load-carrying part and an object adjacent to the load-carrying position based on the acquired point cloud, and a backrest, wherein the connecting part includes a first end fixed to either the left or right end or the upper end of the backrest, an intermediate part extending obliquely backward from the first end in a plan view, and a second end continuous from the intermediate part and supporting the point cloud acquisition unit.

Advantages of the Invention

[0014] The carrier vehicle according to the present invention can specify the horizontal distance between the load loaded on the load loading part and the object adjacent to the load loading position. Therefore, even if a movable shelf, a truck, or the like is displaced from a predetermined position, the load loading position can be corrected later.

Brief Description of the Drawings

[0015]

Figure 1

Figure 2

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Figure 12

Embodiments for Carrying Out the Invention

[0016] Hereinafter, with reference to the accompanying drawings, an embodiment of the carrier vehicle, the connecting portion, the distance specifying method, and the distance specifying program of the present invention will be described. The double-headed arrow X in the figure indicates the left-right direction, the double-headed arrow Y indicates the front-back direction, and the double-headed arrow Z indicates the up-down direction.

[0017] Figure 1 is a side view of the carrier vehicle 1 according to this embodiment, and Figure 2 is a functional block diagram of the control unit 30. The carrier vehicle 1 according to this embodiment is an unmanned carrier vehicle that autonomously travels and performs handling, but this is merely an example, and the carrier vehicle 1 according to the present invention is not limited thereto. For example, the carrier vehicle 1 may be a carrier vehicle that can be used for both manned and unmanned operations.

[0018] As shown in Figures 1 and 2, the carrier vehicle 1 includes a plurality of wheels 10, a vehicle body 11, a drive unit 12, a laser scanner 13, left and right masts 14, a lift bracket 15, left and right forks 16, a lifting unit 17, a backrest 18, a side shift unit 19, left and right carriages 20, left and right reach legs 21, left and right 2D LiDAR sensors 22, left and right connecting portions 23, and a control unit 30. The carrier vehicle 1 is a reach-type forklift, but this is also merely an example, and the carrier vehicle 1 according to the present invention may be a counterbalanced forklift.

[0019] The vehicle body 11 is disposed above the wheels 10, and the drive unit 12 is disposed inside the vehicle body 11. The drive unit 12 is configured to rotate or stop the wheels 10.

[0020] The laser scanner 13 is disposed above the vehicle body 11 and rotates horizontally to irradiate a laser. Then, the laser scanner 13 identifies the current position of the transport vehicle 1 by identifying the position of the reflector disposed in the facility by scanning the reflected light of the laser.

[0021] The left and right masts 14 extend vertically and are disposed in front of the vehicle body 11. The lift bracket 15 has finger bars for fixing the left and right forks 16 and is configured to be lifted and lowered along the left and right masts 14 by the lifting unit 17. The left and right forks 16 correspond to the "load loading part" of the present invention. In this embodiment, the number of forks 16 is four, but it may be two or six and is not particularly limited. By providing the transport vehicle 1 with four forks 16, two pallets (loads) can be lifted simultaneously.

[0022] The backrest 18 is formed in a frame shape, extends vertically and horizontally, and is configured to receive the loaded load W1. Note that only the outer frame of the backrest 18 shown in FIGS. 3 and 5 is illustrated, and this outer frame is disposed outside the forks 16 in the left-right direction.

[0023] The side shift unit 19 has an actuator and is configured to move the backrest 18 in the left-right direction together with the forks 16 by the actuator. Thereby, the side shift unit 19 can adjust the left-right position of the forks 16 with respect to the fork insertion hole of the pallet or adjust the position where the load W1 is loaded. The actuator may be a hydraulic actuator or an electric actuator and is not particularly limited.

[0024] The left and right carriages 20 are respectively provided outside the left and right masts 14, and the left and right reach legs 21 extend forward from the vehicle body 11. Guides for guiding the carriage 20 are provided inside the left and right reach legs 21, and the mast 14 is moved to a forward position or a backward position together with the carriage 20 by a reach cylinder (not shown).

[0025] The left and right two-dimensional LiDAR sensors 22 are constituted by laser scanners and are configured to irradiate a laser while rotating in the horizontal direction and scan the reflected light of the laser to acquire the distances to objects around the two-dimensional LiDAR sensor 22 as a point cloud PG. The two-dimensional LiDAR sensor 22 corresponds to the "point cloud acquisition unit" of the present invention. The point cloud acquisition unit may be, for example, a three-dimensional LiDAR sensor or a three-dimensional ToF (Time of Flight) camera instead of the two-dimensional LiDAR sensor 22, and is not limited to the two-dimensional LiDAR sensor.

[0026] As shown in FIGS. 1 and 3, the left and right connecting portions 23 have a first end portion 23a, an intermediate portion 23b, and a second end portion 23c.

[0027] The first end portion 23a is fixed to the left and right ends of the backrest 18, and the intermediate portion 23b extends obliquely backward from the first end portion 23a in a plan view. The second end portion 23c has a horizontal plane continuous with the intermediate portion 23b and supports the two-dimensional LiDAR sensor 22 by the horizontal plane.

[0028] The length of the intermediate portion 23b is configured such that the two-dimensional LiDAR sensor 22 supported by the second end portion 23c is located outside the side surface of the load loaded on the fork 16. That is, if the width of the backrest 18 is narrow and the load protrudes left and right more than the backrest 18, the length of the intermediate portion 23b will be configured to be longer accordingly.

[0029] FIG. 4 is a plan view showing the laser irradiation range LE of the two-dimensional LiDAR sensor 22, and FIG. 5 is a perspective view showing the laser irradiation range LE of the two-dimensional LiDAR sensor 22. FIGS. 4 and 5 also show the load W1 loaded on the fork 16 and the load W2 loaded adjacent to the load loading position P in front thereof. The load loading position P is, for example, a predetermined loading position of a moving shelf included in the cargo handling plan, a predetermined loading position of the cargo bed of the truck T, or the like.

[0030] As shown in FIGS. 4 and 5, the two-dimensional LiDAR sensor 22 is disposed at a position where it can horizontally irradiate the load W1 loaded on the fork 16 and the load loading position P with a laser. Then, the two-dimensional LiDAR sensor 22 irradiates the laser while rotating horizontally and receives the reflected light, thereby obtaining the distance to the object for each irradiation angle. This distance data is obtained as a point cloud PG.

[0031] FIG. 6A is a diagram showing the point cloud PG obtained by the left two-dimensional LiDAR sensor 22. The X-axis in FIGS. 6A and 6B indicates the distance in the left-right direction, the Y-axis in FIGS. 6A and 6C indicates the distance in the front-rear direction, and the intersection (origin) of the X-axis and the Y-axis indicates the position of the two-dimensional LiDAR sensor 22. Also, the point cloud PG in the attached drawings is an image diagram for showing an example of the point cloud PG to be obtained, and is not the actually obtained point cloud PG. As shown in FIG. 6A, the point cloud PG is obtained along the end faces of the load W1 loaded on the fork 16 and the load W2 loaded adjacent to the load loading position P.

[0032] As shown in FIG. 1, the control unit 30 is disposed inside the vehicle body 11. The control unit 30 is configured by a computer having a storage device, an arithmetic unit, and a memory. The storage device stores a distance specifying program for operating the computer as the distance specifying unit 36 of the present invention.

[0033] As shown in FIG. 2, the control unit 30 includes a storage unit 32, a travel control unit 34, a distance specifying unit 36, a lift control unit 38, and a side shift control unit 40.

[0034] The storage unit 32 stores the cargo handling schedule, and the cargo handling schedule includes the cargo loading position P. The storage unit 32 also includes the positions of the left and right two-dimensional LiDAR sensors 22 and the distance from the retracted position to the extended position of the mast 14.

[0035] The travel control unit 34 is configured to control the drive unit 12, and refers to the cargo loading position P stored in the storage unit 32 and the current position acquired by the laser scanner 13 to drive the carrier vehicle 1 to the cargo loading position P.

[0036] Based on the acquired point cloud PG, the distance specifying unit 36 specifies the left-right direction distance D1 and the front-rear direction distance D2 between the load W1 loaded on the fork 16 and the object adjacent to the cargo loading position P. The method for analyzing the point cloud PG by the distance specifying unit 36 is not particularly limited.

[0037] Based on the distances D1 and D2 between the load W1 and the object adjacent to the cargo loading position P, the distance from the retracted position to the extended position of the mast 14, and the current position of the carrier vehicle 1, the travel control unit 34 calculates the forward distance required for unloading, and may advance the carrier vehicle 1 based on the calculated distance.

[0038] The lifting control unit 38 is configured to control the lifting unit 17, and based on the cargo loading position P stored in the storage unit 32, raises and lowers the fork 16 by the lifting unit 17.

[0039] The side shift control unit 40 is configured to control the side shift unit 19, and based on the left-right direction distance D1 between the load W1 loaded on the fork 16 specified by the distance specifying unit 36 and the object adjacent to the cargo loading position P, the side shift unit 19 moves the load W1 closer to or away from the object adjacent to the cargo loading position P. Thereby, it is possible to squeeze between the load W1 and the load W2 to load the load W1, or to avoid a state where the load W1 overlaps.

[0040] Next, a method for the distance specifying unit 36 to specify the horizontal distance D1 between the load W1 and the load W2 will be described with reference to FIG. 6. FIGS. 6B and 6C show the point group PG in FIG. 6A as histograms in the horizontal and vertical directions.

[0041] As shown in FIG. 6B, according to the frequency distribution on the X-axis, there is a range where there is no distribution in the center. This range indicates an area where the reflection of the laser by the 2D LiDAR sensor 22 is extremely low or non-existent compared to other areas. Therefore, the distance specifying unit 36 can specify this area where there is no laser reflection using the frequency distribution, and by calculating the length D1 of the area, the distance D1 between the side surface of the load W1 and the side surface of the load W2 can be specified.

[0042] On the other hand, as shown in FIG. 6C, according to the frequency distribution on the Y-axis, it can be seen that there are two peak values on the upper side and the lower side. Therefore, the distance specifying unit 36 can specify the distance D2 between the front surface of the load W1 and the front surface of the load W2 by calculating the distance D2 between these two peak values. Alternatively, it can be seen that there are boundaries where the distribution of the point group PG disappears below the lower side of the upper peak value and below the lower side of the lower peak value. Therefore, the distance specifying unit 36 can specify the distance D2 between the front surface of the load W1 and the front surface of the load W2 by calculating the distance between these boundaries.

[0043] In this way, the distance specifying unit 36 analyzes the point group PG acquired by the 2D LiDAR sensor 22 using the frequency distribution, and can specify the horizontal distance D1 and the front-rear distance D2 between the load W1 and the object adjacent to the load loading position P. As a result, even if the moving shelf, the truck T, etc. are displaced from the predetermined position, the carrier vehicle 1 can correct the load loading position P later, so that the load W1 can be loaded at an appropriate position. Note that the histograms in FIGS. 6B and 6C are for explaining the frequency distribution in this specification, and it is not particularly necessary for the distance specifying unit 36 to create a histogram.

[0044] Figures 7 to 10 show examples of information that can be obtained by the frequency distribution analysis by the distance specifying unit 36.

[0045] FIG. 7A shows a point group PG obtained by the two-dimensional LiDAR sensor 22 when the load placement position P is a frame-shaped rack. The left side of FIG. 7A shows two point groups PG obtained by irradiating two frames with a laser. FIGS. 7B and 7C show the obtained point group PG as histograms in the left-right direction and the up-down direction. The distance specifying unit 36 specifies the distance D1 between the side surface of the frame and the side surface of the load W1 by calculating the length of the region without laser reflection by the same method as described above. Also, the distance specifying unit 36 specifies the distance between the front surface of the frame and the front surface of the load W1 by calculating the distance D2 between the two peak values in the up-down direction by the same method as described above.

[0046] Further, FIG. 8A shows a point group PG obtained by the two-dimensional LiDAR sensor 22 when the position of the two-dimensional LiDAR sensor 22 is arranged at the center of the height of the backrest 18. On the right side of FIG. 8A, a point group PG obtained by the reflection of the laser on the end of the backrest 18 is shown. However, also in this case, as shown in FIGS. 8B and 8C, by analyzing using the frequency distribution, a region without laser reflection can be specified at the center in the left-right direction, and the upper peak and the lower peak can be specified in the up-down direction. Therefore, the distance specifying unit 36 can specify the distances D1 and D2 by the same method.

[0047] Further, FIG. 9A shows a point cloud PG acquired by the 2D LiDAR sensor 22 when there is an abnormality in the loading destination space such as a collapse of the load. Above FIG. 9A, the point cloud PG acquired by the reflection of the laser on the abnormality occurrence location is shown. In this case, as shown in FIG. 9B, by analyzing using the frequency distribution, it can be specified that there is no region without distribution in the center in the left-right direction. In this way, the distance specifying unit 36, by analyzing using the frequency distribution, can specify that there is no gap between the load W1 and the load W2, specifically, that there is no region without laser reflection between the peak value on the left side and the peak value on the right side. Thereby, the distance specifying unit 36 can recognize that there is an abnormality in the loading destination space. In this case, the control unit 30 may stop the loading operation of the transport vehicle 1.

[0048] FIG. 10A shows a point cloud PG acquired by irradiating only the load W1 with a laser by the 2D LiDAR sensor 22. As shown in FIGS. 10B and 10C, the distance specifying unit 36 specifies a region from the 2D LiDAR sensor 22 (origin) to the region with distribution or to the peak value by analyzing the point cloud PG data using the frequency distribution. Thereby, the distance specifying unit 36 can also specify the left-right direction distance D3 and the front-back direction distance D4 between the 2D LiDAR sensor 22 and the load W1 by calculating the distances D3 and D4 of the specified region.

[0049] Conventionally, in the analysis using a LiDAR sensor, the distance between the surrounding objects and the LiDAR sensor is specified by comparing and matching the shape and features of the objects specified in advance with the acquired point cloud PG. In this method, when the unloading destination is a thin frame-shaped structure, when the surrounding structure including the backrest 18 is detected by the LiDAR sensor, or when there is an abnormality in the loading destination space, it is difficult to stably acquire the distance to the surrounding objects.

[0050] In addition, in the analysis using a conventional LiDAR sensor, since it is a method of recognizing the shape and features of a previously specified object, the position of the LiDAR sensor is adjusted so that the laser is irradiated onto the load W1 and the laser is not blocked. Therefore, with the conventional method, it is not possible to obtain the mutual positional relationship between the carrier vehicle 1, the load W1, and the object adjacent to the load loading position P only with the LiDAR sensor. Accordingly, with the conventional method, it is necessary to separately perform other distance measurements, interference confirmation, etc., and for that purpose, it was necessary to separately arrange other sensors, etc.

[0051] On the other hand, according to the method of the present invention, by using only the two-dimensional LiDAR sensors 22 on the left and right, it is possible to obtain the mutual positional relationship between the carrier vehicle 1, the loaded load W1, the object or load W2 adjacent to the load loading position P. Moreover, according to the method of the present invention, when the unloading destination is a thin frame-shaped structure, when the surrounding structure including the backrest 18 is detected by the two-dimensional LiDAR sensor 22, or when there is an abnormality in the loading destination space, it is always possible to stably obtain the distance between the load W1 and the load W2.

[0052] Next, with reference to FIGS. 11 and 12, an example of a series of operations of the carrier vehicle 1 according to the present invention will be described. In this description, the carrier vehicle 1 in FIGS. 11 and 12 is described as a counterbalanced forklift. Therefore, it is described that the position of the mast 14 in the front-rear direction does not move.

[0053] (1)(1-1) As shown in FIG. 11A, before the carrier vehicle 1 scoops up the load W3, the laser is irradiated onto the load W3 by the two-dimensional LiDAR sensors 22 on the left and right. (1-2) Next, the carrier vehicle 1 analyzes the acquired point cloud PG using the frequency distribution by the distance specifying unit 36 to specify the positions of the left and right ends of this load W3 and the position of the center in the left-right direction of the load W3. (1-3) Next, the carrier vehicle 1 calculates the distance D5 between the position of the center in the left-right direction of the load W3 and the position of the center in the left-right direction of the backrest 18 by the distance specifying unit 36. (1-4) Further, based on the calculated distance D5, the carrier vehicle 1 moves the fork 16 in the left-right direction by the side shift unit 19, thereby correcting the center deviation between the fork 16 and the load W3.

[0054] Note that, for example, when the carrier vehicle 1 is a side fork vehicle, the carrier vehicle 1 can correct the center deviation between the fork 16 and the load W3 by moving the vehicle body 11 by the travel control unit 34 based on the specified distance D5.

[0055] (2)(2-1) Next, the carrier vehicle 1 scoops up the load W3 (W1) and transports it to the truck T, and as shown in FIG. 11B, while irradiating the laser toward the loading platform of the truck T by the two-dimensional LiDAR sensor 22 on the truck T side, it travels parallel to the loading platform of the truck T. (2-2) Next, the carrier vehicle 1 analyzes the acquired point cloud PG using the frequency distribution by the distance specifying unit 36, thereby detecting the side surface of the object (load W2) adjacent to the load loading position P on the loading platform, and specifying the mutual positional relationship among the position of the detected side surface, the position of the two-dimensional LiDAR sensor 22, and the position of the load W1. (2-3) Next, when the carrier vehicle 1 detects the side surface of this object, it changes its direction toward the truck T side by the travel control unit 34 based on the positional relationship among the position of the specified side surface, the position of the two-dimensional LiDAR sensor 22, and the load W1.

[0056] (3)(3-1) Next, as shown in FIG. 11C, before the carrier vehicle 1 advances toward the load loading position P, it irradiates the laser in the horizontal direction by the two-dimensional LiDAR sensor 22. (3-2) Next, the carrier vehicle 1 analyzes the acquired point cloud PG using the frequency distribution by the distance specifying unit 36 to specify the distance D1 between the load W1 and the load W2, and thereby determines whether or not the load W1 interferes with the load W2. At this time, as described above, when the carrier vehicle 1 specifies that an abnormality has occurred, it may abort the handling operation.

[0057] (4) Next, the carrier vehicle 1 advances to the loading position P by the travel control unit 34 based on the front-rear direction distance D2 between the load W1 and the load W2 specified by the distance specifying unit 36. (4-2) Next, as shown in Fig. 12A, the carrier vehicle 1 irradiates a laser by the two-dimensional LiDAR sensor 22 before lowering the load W1. (4-3) Next, the carrier vehicle 1 specifies the distance D1 between the load W1 and the load W2 by analyzing the acquired point cloud PG using the frequency distribution by the distance specifying unit 36. (4-4) Next, the carrier vehicle 1 specifies the control amount of the side shift unit 19 by the side shift control unit 40 based on the specified distance D1.

[0058] As a result, the carrier vehicle 1 can appropriately move the load W1 closer to the load W2 by the side shift unit 19.

[0059] (5) (5-1) Next, as shown in Fig. 12B, when the carrier vehicle 1 moves the fork 16 to the left by the side shift unit 19, the carrier vehicle 1 irradiates a laser by the two-dimensional LiDAR sensor 22. (5-2) Next, the carrier vehicle 1 calculates the left-right direction and front-rear direction distances D3 and D4 between the two-dimensional LiDAR sensor 22 and the load W1 by analyzing the acquired point cloud PG using the frequency distribution by the distance specifying unit 36, and moves the fork 16 while specifying the positional relationship between the two-dimensional LiDAR sensor 22 and the load W1. (5-3) At this time, while the carrier vehicle 1 is being moved by the side shift unit 19, the distance specifying unit 36 determines whether or not the positional relationship between the two-dimensional LiDAR sensor 22 and the load W1 changes.

[0060] As a result, the carrier vehicle 1 can detect that the load W1 starts to slide on the fork 16. Therefore, for example, the carrier vehicle 1 can detect that the load W1 has been pressed against an object such as the front panel or the rear panel of the truck T, and after this detection, prevent damage to the front panel or the rear panel by stopping the movement of the fork 16.

[0061] On the other hand, if the transport vehicle 1 wants to press the load W1 against the load W2, after detecting that the load W1 starts to slide on the fork 16, the transport vehicle 1 may be configured to stop the movement of the side shift unit.

[0062] (6)(6-1) Next, as shown in FIG. 12C, when the transport vehicle 1 pulls out the fork 16 from the load W3, the two-dimensional LiDAR sensor 22 irradiates a laser. (6-2) Next, the transport vehicle 1 analyzes the acquired point cloud PG using the frequency distribution by the distance specifying unit 36, and while specifying the positional relationship between the two-dimensional LiDAR sensor 22 and the load W3, pulls out the fork 16.

[0063] Thereby, the transport vehicle 1 detects that the load W3 moves together with the fork 16, and thereby prevents the load W3 from being dragged by the fork 16.

[0064] As described above, since the two-dimensional LiDAR sensor 22 is arranged at a position where it can irradiate the load W1 and the load loading position P with a laser, the load W1 and an object (for example, the load W2) adjacent to the load loading position P are irradiated with the laser, and the reflected light from the load W1 and the object adjacent to the load loading position P can be detected to obtain the point cloud PG. Thereby, the transport vehicle can analyze the acquired point cloud PG by the distance specifying unit 36 to specify the distances D1 and D2 between the load W1 and the load W2. Therefore, even if the mobile rack, the truck T, etc. are displaced from the predetermined positions, the load loading position P can be corrected later, and the cargo handling work can be appropriately performed.

[0065] Moreover, the memory unit 32 stores the position of the 2D LiDAR sensor 22 as well. The distance specifying unit 36 analyzes the acquired point cloud PG to specify not only the distances D1 and D2 between the load W1 and the load W2, but also the distances D3 and D4 between the load W1 and the 2D LiDAR sensor 22. That is, the carrier vehicle 1 can specify three relative positional relationships among the load W1, the load W2, and the 2D LiDAR sensor 22 (carrier vehicle 1). Thereby, the carrier vehicle 1 can perform the series of operations (1) to (6) described above.

[0066] As described above, one embodiment of the carrier vehicle, the connecting part, the distance specifying method, and the distance specifying program of the present invention has been described. However, the present invention is not limited to the above embodiment. For example, the carrier vehicle according to the present invention may be implemented by the following modification examples.

[0067] <Modification Example> · The second end portion 23c of the connecting part 23 may not be located above the backrest 18. In this case, the point cloud PG acquired by the 2D LiDAR sensor 22 becomes the point cloud PG shown in FIG. 8A. However, as already described, the distance specifying unit 36 can specify the distance between the load W1 and the load W2 and the like. Further, the first end portion 23a of the connecting part 23 may be provided at the upper end of the backrest 18.

[0068] · If the 2D LiDAR sensor 22 is arranged, for example, at a position where it can irradiate a laser to the load W1 loaded on the load loading part 16 and an object adjacent to the load loading position P, it may be fixed to, for example, the vehicle body 11 or the finger bar. Or, the first end portion 23a of the connecting part 23 may be fixed to the side surface (see FIG. 1) of the vertically provided portion 16a extending in the vertical direction of the fork 16. Alternatively, the 2D LiDAR sensor 22 may be fixed to the vehicle body 11, the vertically provided portion 16a of the fork 16, or the finger bar via the connecting part.

[0069] · The load loading part may be constituted by a platen, for example, instead of the fork 16.

Description of Reference Numerals

[0070] The load loaded on the W1 load loading part The load loaded adjacent to the W2 load loading position The load loaded at the W3 load loading position D1 Distance in the left - right direction D2 Distance in the front - rear direction P Load loading position LE Laser irradiation range PG Point cloud T Truck 1 Carrier vehicle 10 Wheels 11 Vehicle body 12 Driving part 13 Laser scanner 14 Mast 15 Lift bracket 16 Fork (load loading part) 16a Vertically - installed part 17 Lifting part 18 Backrest 19 Side - shift part 20 Carriage 21 Reach leg 22 2 - Dimensional LiDAR sensor (point cloud acquisition part) 23 Connecting part 23a First end part 23b Intermediate part 23c Second end part 30 Control part 32 Memory part 34 Travel control part 36 Distance determination part 38 Lifting control part 40 Side - shift control part

Claims

1. a load-carrying part, a point cloud acquisition part that is arranged at a position where a laser can be irradiated onto the load loaded on the load-carrying part and the load loading position, and that acquires a point cloud in the horizontal direction by irradiating the laser only horizontally, a distance specifying part that specifies a distance in the left-right direction, the front-rear direction, or any one of these directions between the load loaded on the load-carrying part and an object adjacent to the load loading position based only on the acquired point cloud in the horizontal direction, and a carrier vehicle, wherein the point cloud acquisition part is composed of one laser scanner on either the left or the right, or one laser scanner on each of the left and the right.

2. The carrier vehicle is a forklift and includes a backrest, and the point cloud acquisition part is provided on the backrest, the carrier vehicle according to claim 1.

3. further including a connecting part, wherein the connecting part is connected to the backrest and the point cloud acquisition part, and arranges the point cloud acquisition part diagonally behind either the left or the right end of the backrest in a plan view, the carrier vehicle according to claim 2.

4. A method for specifying a left-right distance between a load loaded on a load-carrying part of a carrier vehicle and an object adjacent to the load loading position, including the steps of: acquiring a point cloud in the horizontal direction by irradiating a laser horizontally onto the load loaded on the load-carrying part and the object adjacent to the load loading position with one laser scanner; and specifying a left-right distance between the load loaded on the load-carrying part and the object adjacent to the load loading position based only on the acquired point cloud in the horizontal direction, the distance specifying method.

5. A method for specifying a front-rear distance between a load loaded on a load-carrying part of a carrier vehicle and an object adjacent to the load loading position, A step of horizontally irradiating a laser on the load loaded on the load loading part and the object adjacent to the load loading position by one laser scanner to obtain a point cloud in the horizontal direction; A distance specifying method including a step of specifying a distance in the front-rear direction between the load loaded on the load loading part and the object adjacent to the load loading position based only on the obtained point cloud in the horizontal direction.

6. A load loading part; A point cloud acquisition unit configured to be able to horizontally irradiate a laser on the load loaded on the load loading part and the load loading position to acquire a point cloud in the horizontal direction; A distance specifying program used for a transport vehicle including a computer, The point cloud acquisition unit is composed of one laser scanner on either the left or right, or one laser scanner on each of the left and right; In the computer, A distance specifying program for executing a step of specifying a distance in the left-right direction, the front-rear direction, or any one of the directions between the load loaded on the load loading part and the object adjacent to the load loading position based only on the point cloud in the horizontal direction obtained by one laser scanner.

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