Cargo handling system and cargo handling program

Abstract

To safely and efficiently operate an unmanned cargo handling vehicle with a simple configuration.SOLUTION: A cargo handling system 1 includes: an unmanned cargo handling vehicle 20; a work area 50 including a first area E1 where the unmanned cargo handling vehicle 20 performs work and a second area E2 around the first area E1; a monitoring camera 51 that monitors the work area 50; and a control part 37. The control part 37 detects obstacles in the second area E2 and a third area E3 based on information acquired by the monitoring camera 51, and limits the speed of the unmanned cargo handling vehicle 20 if the obstacle is detected.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a cargo handling system and a cargo handling program.

Background Art

[0002] Conventionally, a cargo handling system that operates unmanned cargo handling vehicles for performing cargo handling work without human intervention has been known (see, for example, Patent Document 1). In this type of cargo handling system, generally, the work area is surrounded by a safety fence to ensure safety so that no one enters the work area. When a person enters the work area beyond the safety fence, all unmanned cargo handling vehicles are stopped until the person exits. Alternatively, at a site where there are many opportunities for people to approach unmanned cargo handling vehicles, the unmanned cargo handling vehicle is decelerated or stopped according to the distance between the unmanned cargo handling vehicle and surrounding people and objects without surrounding the work area with a safety fence.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, when the work area is surrounded by a safety fence, the equipment cost becomes high. Also, changing the layout of the work area becomes complicated. On the other hand, when controlling the vehicle speed according to the distance from surrounding objects, the conveyance efficiency deteriorates because the conveyance speed is likely to be restricted.

[0005] The present invention has been made in view of the above circumstances, and an object thereof is to safely and efficiently operate an unmanned cargo handling vehicle with a simple configuration.

Means for Solving the Problems

[0006] The cargo handling system according to the present invention is An unmanned transport vehicle, An operation area including a first section where the unmanned transport vehicle performs operations and a second section around the first section, Monitoring means for monitoring the operation area, A detection unit that detects an obstacle in the second section based on information acquired by the monitoring means, A control unit that limits the speed of the unmanned transport vehicle when the detection unit detects an obstacle, is provided.

Advantages of the Invention

[0007] According to the present invention, the unmanned transport vehicle can be operated safely and efficiently with a simple configuration.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Mode for Carrying Out the Invention

[0009] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0010] [Configuration of the Transport System] FIG. 1 is a diagram showing a transport system 1 according to the present embodiment, and FIG. 2 is a block diagram showing a schematic control configuration of the transport system 1. As shown in these figures, the handling system 1 performs predetermined handling operations (such as loading and unloading, transportation, stacking, picking, sorting, aligning, and associated operations) in the work area 50 by an unmanned handling vehicle (hereinafter simply referred to as "handling vehicle") 20. The handling system 1 is a system including, for example, a WMS (Warehouse Management System), a WES (Warehouse Execution System), a WCS (Warehouse Control System), and the like.

[0011] The work area 50 is, for example, a warehouse or the like, and in this embodiment, it is divided into three areas: a first area E1, a second area E2, and a third area E3. This division is set (stored) on the management server 30, and actually, elements for visually recognizing the boundaries between areas (such as floor coloring, boundary lines, safety fences, etc.) may not be necessary. However, in FIG. 1, for the sake of convenience, the displays of the first area E1 to the third area E3 are made different.

[0012] The first area E1 is an example of the first section according to the present invention and is an area where the handling vehicle 20 performs operations. The handling vehicle 20 is operated only within the range of the first area E1, at least during operation. The first area E1 is set to the highest (most dangerous) safety level 3.

[0013] The second area E2 and the third area E3 are examples of the second section according to the present invention and are set step by step around the first area E1. Among these, the second area E2 is arranged around the first area E1. The second area E2 of the present embodiment has a predetermined width w2 over the entire circumference of the first area E1 and surrounds the first area E1. The width w2 of the second area E2 is set so that a person moving in the second area E2 is always captured by the monitoring camera 51 based on the frame rate of the monitoring camera 51 and the moving speed of a person described later. For example, when the frame rate of the monitoring camera 51 is 10 fps or more, the width w2 of the second area E2 is set to 3 m or more, which is the maximum distance that a person can move in 100 ms (a person cannot move at 30 m / s). The safety level of the second area E2 is set to the second highest level 2 next to the first area E1. The third area E3 is arranged around the second area E2. The third area E3 of the present embodiment has a predetermined width w3 over the entire circumference of the second area E2 and surrounds the second area E2. The width w3 of the third area E3 is set so that a person moving in the second area E2 is always captured by the monitoring camera 51 based on the frame rate of the monitoring camera 51 and the moving speed of a person, similar to the width w2 of the second area E2, and is set to, for example, 3 m or more. The safety level of the third area E3 is set to the lowest level 3. Note that the second area E2 and the third area E3 (the second section) only need to be adjacent to a section with a higher safety level, and their shapes and ranges are not particularly limited.

[0014] A monitoring camera 51, a speaker 52, and a warning light 53 are installed in the work area 50. However, the speaker 52 and the warning light 53 may not be installed. The monitoring camera 51 is an example of the monitoring means according to the present invention. It captures the work area 50 and outputs the acquired image to the management server 30. A plurality of monitoring cameras 51 that capture images from different directions are installed so that the entire areas of the first area E1 to the third area E3 can be captured without blind spots. The speaker 52 outputs a predetermined voice toward workers in the work area 50 based on an output command from the management server 30. The warning lamp 53 is installed at a high place such as a wall surface, etc., and emits light in a predetermined light emission mode based on an output command from the management server 30.

[0015] Specifically, the cargo handling system 1 includes at least one cargo handling vehicle 20 and a management server 30.

[0016] The cargo handling vehicle 20 is a vehicle that performs cargo handling operations, such as a forklift that can travel on the road without using rails or the like. The cargo handling vehicle 20 holds a load or a pallet by a pair of forks on the left and right and performs various cargo handling operations. The cargo handling vehicle 20 of the present embodiment is an automated guided forklift (AGF) that can operate automatically (unmanned) and operates based on an operation command or the like from the management server 30.

[0017] Specifically, the cargo handling vehicle 20 includes a vehicle body drive unit 21, a fork drive unit 28, an operation unit 22, a display unit 23, a communication unit 24, a position measurement device 25, a laser scanner 29, a storage unit 26, and a control unit 27.

[0018] The vehicle body drive unit 21 includes a traveling motor and a steering motor (both not shown in the figure), which are drive sources of the cargo handling vehicle 20. The traveling motor drives the drive wheels among the wheels. The steering motor rotates (steers) the steering wheels among the wheels. Each motor is powered by a battery (not shown in the figure). Note that the drive source is not limited to a motor, and an internal combustion engine or the like may be used.

[0019] The fork drive unit 28 is a drive source for operating a pair of forks. The fork drive unit 28 of the present embodiment includes an inclination cylinder, a lifting cylinder, and a reach cylinder (all not shown in the figure) for tilting, lifting, and advancing / retreating (extending / contracting) a pair of forks. These cylinders are piston cylinders driven by hydraulic pressure (for example, oil pressure).

[0020] The operation unit 22 is an operation means for a driver to perform various operations during manned (manual) driving. The operation unit 22 includes, for example, a steering wheel, pedals, levers, various buttons, etc., and outputs an operation signal corresponding to these operation contents to the control unit 27. The display unit 23 is, for example, a liquid crystal display, an organic electroluminescence display, or other displays, and displays various information based on a display signal input from the control unit 27. Note that the display unit 23 may be a touch panel that also serves as a part of the operation unit 22, or may include a speaker capable of voice display (output). The communication unit 24 is a communication device capable of transmitting and receiving various information to and from the management server 30, other handling vehicles 20, and the like.

[0021] The position measurement device 25 measures the position of the handling vehicle 20 itself. The information on the self-position acquired by the position measurement device 25 is transmitted to, for example, the management server 30, and is also used by the handling vehicle 20 for its own position control. The specific configuration of the position measurement device 25 is not particularly limited, and for example, it may utilize GNSS (Global Navigation Satellite System), SLAM (Simultaneous Localization and Mapping) technology, indoor positioning (indoor mapping) technology, or other technologies.

[0022] The laser scanner 29 detects (senses) an object around the vehicle body by acquiring distance information within a predetermined scan area (measurement area), and outputs the result to the control unit 27. The laser scanner 29 of the present embodiment is a two-dimensional distance sensor (for example, two-dimensional LiDAR (Laser Imaging Detection and Ranging)) having a planar scan area substantially orthogonal to the vehicle width direction. However, the type of the sensor and the like of the laser scanner 29 are not particularly limited as long as it can detect an object around it.

[0023] The storage unit 26 is a memory composed of, for example, RAM (Random Access Memory), ROM (Read Only Memory), etc., stores various programs and data, and also functions as a work area for the control unit 27. The control unit 27 is composed of, for example, a CPU (Central Processing Unit) or the like, and controls the operations of each part of the cargo handling vehicle 20. Specifically, the control unit 27 operates each part based on a control command from the management server 30 or the operation content of the operation unit 22, or develops a program stored in advance in the storage unit 26 and executes various processes in cooperation with the developed program.

[0024] The management server 30 centrally controls the cargo handling system 1 and is configured to be able to control the operations of a plurality of cargo handling vehicles 20. The management server 30 may be a personal computer, a smartphone, a tablet terminal, or the like. Specifically, the management server 30 includes an operation unit 31, a display unit 32, a communication unit 34, a storage unit 36, and a control unit 37.

[0025] The operation unit 31 is an operation means for an operator to perform various operations for operating the management server 30, and includes, for example, a pointing device such as a mouse or a keyboard. The display unit 32 is, for example, a liquid crystal display, an organic electroluminescence display, or other displays. The display unit 32 displays various information based on a display signal input from the control unit 37. Further, the display unit 32 may be a touch panel that also serves as at least a part of the operation unit 31. The display unit 32 of the present embodiment displays, for example, the position information of the first area E1 to the third area E3 based on a user operation. The communication unit 34 is a communication device capable of transmitting and receiving various information to and from each cargo handling vehicle 20.

[0026] The storage unit 36 is a memory composed of, for example, a RAM (Random Access Memory) or a ROM (Read Only Memory), stores various programs and data, and also functions as a working area for the control unit 37. The storage unit 36 of the present embodiment stores the position information of the first area E1 to the third area E3. The control unit 37 is composed of, for example, a CPU (Central Processing Unit) or the like, and controls the operations of each part of the management server 30. Specifically, the control unit 37 expands a program stored in advance in the storage unit 36 based on the operation content of the operation unit 31 and the like, and executes various processes in cooperation with the expanded program.

[0027] [Speed Control Processing] Subsequently, the speed control process for controlling the operation (speed) of the cargo handling vehicle 20 will be described. FIG. 3 is a flowchart showing the procedure of the speed control process.

[0028] The speed control process is a process of controlling the speed of the cargo handling vehicle 20 based on the presence or absence of obstacles in the work area 50. This speed control process is executed in cooperation with the cargo handling vehicle 20, for example, by the control unit 37 of the management server 30 reading and expanding the corresponding program from the storage unit 36.

[0029] As shown in FIG. 3, first, the control unit 37 of the management server 30 transmits an operation command to the cargo handling vehicle 20 to cause it to perform a predetermined cargo handling operation in the first area E1 of the work area 50 (step S1). Here, the management server 30 designates, for example, specific coordinates for the cargo handling vehicle 20 and causes it to perform operations such as transporting goods to the specified position. When the moving speed of the cargo handling vehicle 20 is not particularly restricted, it travels and works at a predetermined normal speed (for example, 1.0 m / s).

[0030] When the cargo handling operation is started, the control unit 27 of the cargo handling vehicle 20 performs a scan of the surroundings using the laser scanner 29 mounted on the vehicle body to detect obstacles (step S2). Here, the "obstacle" includes not only stationary objects such as shelves, pillars, and walls, but also moving objects (mobile objects) such as humans like workers and carts. More specifically, the obstacle is an object different from the plan held by the management server 30 (or the cargo handling vehicle 20). The control unit 27 may acquire in advance the position information of objects other than the detection target object, and regard all the differences between the information of the object and the information of the monitoring camera 51 as obstacles. Note that other cargo handling vehicles 20 may be excluded from the detection target based on the position information held by the management server 30.

[0031] Next, based on the detection result in step S2, the control unit 27 determines whether there is an obstacle around the own vehicle (within a predetermined distance) (step S3). When it is determined that there is an obstacle around the own vehicle (step S3; Yes), the control unit 27 decelerates or stops the vehicle body (step S4), and then transfers the process to step S13 described later. In step S4, for example, if the obstacle approaches to about 1 m, decelerate, and if it approaches to 300 mm or less, stop. Note that the processes in steps S2 and S3 are mainly performed by the cargo handling vehicle 20, different from other steps, and may be executed at any time independently of other steps.

[0032] On the other hand, in step S3, when it is determined that there is no obstacle around the cargo handling vehicle 20 (step S3; No), the control unit 37 of the management server 30 detects an obstacle from the image acquired by the monitoring camera 51 installed in the work area 50 (step S5).

[0033] Next, based on the detection result in step S5, the control unit 37 determines whether there is an obstacle in the first area E1 (step S6). When it is determined that an obstacle exists in the first area E1 (step S6; Yes), the control unit 37 restricts the moving speed of all the handling vehicles 20 operating in the first area E1 to a "very low speed (for example, 0.3 m / s)", which is lower than the normal speed (step S7). More specifically, in this case, the operation of the handling vehicle 20 complies with "JIS D 6802:2022 Automated guided vehicles and automated guided vehicle systems - Safety requirements and verification". In this case, the control unit 37 of the management server 30 may turn on the warning lamp 53 or output a warning sound from the speaker 52 to warn (notify) the surrounding workers (including the person who has intruded) of the intrusion of the obstacle into the first area E1. Thereafter, the control unit 37 proceeds to step S13, which will be described later.

[0034] If it is determined in step S6 that no obstacle exists in the first area E1 (step S6; No), the control unit 37 determines whether an obstacle exists in the second area E2 based on the detection result of step S5 (step S8). When it is determined that an obstacle exists in the second area E2 (step S8; Yes), the control unit 37 restricts the moving speed of all the handling vehicles 20 operating in the first area E1 to a "low speed (for example, 0.5 m / s)", which is lower than the normal speed and higher than the very low speed (step S9). In this case, the control unit 37 of the management server 30 may turn on the warning lamp 53 or output a warning sound from the speaker 52 to warn (notify) the surrounding workers (including the person who has intruded) of the intrusion of the obstacle into the second area E2. Thereafter, the control unit 37 proceeds to step S13, which will be described later.

[0035] If it is determined in step S8 that no obstacle exists in the second area E2 (step S8; No), the control unit 37 determines whether an obstacle exists in the third area E3 based on the detection result of step S5 (step S10). When it is determined that there is an obstacle in the third area E3 (step S10; Yes), the control unit 37 restricts the moving speed of all the handling vehicles 20 operating in the first area E1 to "medium speed (for example, 0.7 m / s)", which is smaller than the normal speed and larger than the low speed (step S11). In this case, the control unit 37 of the management server 30 may turn on the warning light 53 or output a warning sound from the speaker 52 to warn (notify) the surrounding workers (including the person who has entered) and others of the intrusion of the obstacle into the third area E3. Thereafter, the control unit 37 proceeds to step S13 described later.

[0036] In step S10, when it is determined that there is no obstacle in the third area E3 (step S10; No), the control unit 37 operates all the handling vehicles 20 operating in the first area E1 at the unrestricted normal speed (for example, 1.0 m / s) (step S12).

[0037] Next, the control unit 37 determines whether to end the speed control process (step S13). If it is determined not to end (step S13; No), the process proceeds to step S1 described above. On the other hand, for example, if it is determined to end the speed control process due to reasons such as the completion of a predetermined handling operation (step S13; Yes), the control unit 37 ends the speed control process.

[0038] [Technical Effects of the Present Embodiment] As described above, according to the present embodiment, the work area 50 is divided into a first area E1 where the handling vehicle 20 performs work, and a second area E2 (and / or a third area E3. Hereinafter referred to as "the second area E2 etc.") around the first area E1. Then, based on the information acquired by the monitoring camera 51 that monitors the work area 50, an obstacle in the second area E2 etc. is detected, and when the obstacle is detected, the speed of the handling vehicle 20 is restricted. This makes it possible to ensure safety without the need to install a safety fence. Also, in an operation without a monitoring camera 51 (for example, an operation that controls the speed according to the distance between the vehicle and surrounding objects), it is necessary to widen the peripheral detection area of the vehicle in order to avoid contact with people, and as a result, the vehicle frequently decelerates and stops. With the method of this embodiment, such a situation can be avoided, and the peripheral detection area of the vehicle (for example, the detection range of the laser scanner 29) can be minimized. Consequently, the conveyance efficiency can be improved. Therefore, the cargo handling vehicle 20 can be operated safely and efficiently with a simple configuration. Consequently, even in an environment where, for example, the frequency of human approach varies (such as at night when there are no people, but during the day when workers are present irregularly), operations can be performed with high conveyance efficiency without increasing equipment costs.

[0039] Also, according to this embodiment, after the speed of the cargo handling vehicle 20 is restricted in steps S7, S9, and S11 of the speed control process, when no obstacle is detected in the second area E2 or the like (step S13; No, S1, S2, S3; No, S5, S6; No, S8; No, S10; No), the speed of the cargo handling vehicle 20 returns to the state before the speed was restricted (normal speed) (step S12). This makes it possible to return the speed of the cargo handling vehicle 20 without any special control, and the cargo handling vehicle 20 can be operated more safely and efficiently.

[0040] Also, according to this embodiment, the width of the second area E2 or the like is set based on the performance of the monitoring camera 51 and the moving speed of a moving object (human). This makes it possible to avoid a situation where a human moving through the second area E2 or the like passes through the second area E2 or the like during the shooting interval of the monitoring camera 51. That is, a human moving through the second area E2 or the like can be surely captured by the monitoring camera 51.

[0041] Also, according to this embodiment, when an obstacle is detected in the second area E2 or the like, the warning light 53 installed in the work area 50 lights up, or a warning sound is output from the speaker 52. As a result, for example, it is possible to notify a person who has intruded or a surrounding worker of intrusion into or approach to the first area E1, ensuring safety more reliably. In addition, for example, the warning mode may be strengthened as the area where intrusion has occurred is closer to the first area E1, and the warning mode may be changed according to the area where the obstacle has intruded.

[0042] Further, according to the present embodiment, position information of the first area E1, the second area E2, etc. is stored, and the position information of the first area E1, the second area E2, etc. is displayed on the display unit 32 based on a user operation. As a result, the user can check the range of each area at any time.

[0043] [Modification Example] In the above embodiment, the first area E1 to the third area E3 are fixed to the work area 50. However, each of these areas may change dynamically according to the position of the loading vehicle 20. In this case, for example, as shown in FIGS. 4(a) and 4(b), the control unit 37 of the management server 30 may acquire the position information of the loading vehicle 20 at any time and set each area around the position of the loading vehicle 20. Specifically, as shown in FIG. 5, after the loading operation is started, the control unit 37 may set the first area E1 around the position of the loading vehicle 20 and set the second area E2 and the third area E3 around the first area E1 based on the position of the loading vehicle 20 (step S1a). Steps S2 to S13 thereafter may be executed in the same manner as in the above embodiment. As a result, each area can be set only around the loading vehicle 20, reducing restrictions in terms of operation. This method can be suitably applied when the working range 50a of the loading vehicle 20 is flat and there are no other obstacles.

[0044] [Others] Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments (including modification examples). For example, in the above embodiment, the monitoring camera 51 was exemplified as the monitoring means for monitoring the work area 50. However, as long as the monitoring means can detect obstacles within the work area 50, the type of sensor and the like are not particularly limited, and for example, 2D-LiDAR, 3D-LiDAR, a light curtain, etc. may be used.

[0045] Also, in the above embodiment, the work area 50 was assumed to include three areas, namely the first area E1 to the third area E3. However, the number of sections included in the work area 50 is not particularly limited as long as it includes at least the first area E1 and the second area E2 (the first section and the second section).

[0046] In addition, the unmanned material handling vehicle according to the present invention only needs to be capable of unmanned driving (automatic driving), and includes those capable of manned driving (including remote operation) and those capable of switching between manned driving and unmanned driving. Furthermore, the present invention is applicable to a material handling system in which manned material handling vehicles and unmanned material handling vehicles are mixed, and can also be used as an assist function for manned driving.

[0047] Moreover, the material handling vehicle according to the present invention is not limited to a forklift as long as it travels to perform material handling, and includes, for example, an automated guided vehicle (AGV) that travels unmanned and an autonomous mobile robot (AMR). In addition, the details shown in the above embodiment can be appropriately changed without departing from the gist of the invention.

Explanation of Reference Numerals

[0048] 1 Material handling system 20 Unmanned material handling vehicle 24 Communication unit 25 Position measurement device 27 Control unit 29 Laser scanner 30 Management server 32 Display unit 34 Communication unit 36 Storage unit 37 Control Unit (Detection Unit, First Setting Unit, Second Setting Unit) 50 Work Area 50a Working Range 51 Surveillance Camera (Surveillance Means) 52 Speaker 53 Warning Light E1 First Area (First Section) E2 Second Area (Second Section) E3 Third Area (Second Section) w2 Width of the Second Area w3 Width of the Third Area

Claims

1. An unmanned cargo handling vehicle, A work area including a first section where the unmanned cargo handling vehicle performs work and a second section around the first section, Monitoring means for monitoring the work area, A detection unit that detects obstacles in the second section based on information acquired by the monitoring means, A control unit that limits the speed of the unmanned cargo handling vehicle when the detection unit detects an obstacle, A cargo handling system comprising the above.

2. After the control unit limits the speed of the unmanned cargo handling vehicle, when the detection unit no longer detects the obstacle in the second section, the control unit returns the speed of the unmanned cargo handling vehicle to the state before the speed limit, The cargo handling system according to Claim 1.

3. The obstacle is a moving object and a stationary object including a human, The cargo handling system according to Claim 1.

4. The obstacle includes a human, The width of the second section is set based on the performance of the monitoring means and the moving speed of a human, The cargo handling system according to Claim 1.

5. A first setting unit that sets the first section around the unmanned cargo handling vehicle based on the position of the unmanned cargo handling vehicle, A second setting unit that sets the second section around the first section, Comprising the above, The cargo handling system according to Claim 1.

6. Equipped with a warning light or a speaker installed in the work area, When the detection unit detects an obstacle, the control unit turns on the warning light or outputs a warning sound from the speaker, The cargo handling system according to Claim 1.

7. A storage unit that stores the position information of the first section and the second section, A display unit that displays the position information of the first section and the second section based on a user operation, comprising the above, The cargo handling system according to Claim 1.

8. An unmanned cargo handling vehicle, A work area including a first section where the unmanned cargo handling vehicle performs work and a second section around the first section, Monitoring means for monitoring the work area, A computer of a cargo handling system comprising the above, A detection unit that detects obstacles in the second section based on information acquired by the monitoring means, A control unit that limits the speed of the unmanned cargo handling vehicle when the detection unit detects an obstacle, A cargo handling program that functions as the above.

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