Worksite management system and worksite management method

Abstract

This worksite management system comprises: a target water-spraying area setting unit for setting a target water-spraying area in a work area of a worksite where a transport vehicle can travel; and a water-spraying data generation unit that calculates an evaluation function including a water-spraying evaluation item related to the spraying of water by an unmanned water-spraying vehicle, and that generates a water-spraying path indicating a target trajectory for the unmanned water-spraying vehicle in the target water-spraying area so that the extent of an evaluation value of the evaluation function is improved.

Description

Work site management system and work site management method

[0001] The present disclosure relates to a work site management system and a work site management method.

[0002] In the technical field of work site management systems, a work site management system that generates a water sprinkling path for an unmanned water sprinkling vehicle, as disclosed in Patent Document 1, is known.

[0003] International Publication No. 2022 / 209192

[0004] The work site has a work area including at least one of a loading area and an unloading area. By spraying water on the work area, the spread of dust or sand in the work area is suppressed. There is a demand for technology that can efficiently spray water on a target water spray area set in the work area.

[0005] The present disclosure aims to efficiently spray water onto a target watering area set in a work area.

[0006] According to the present disclosure, a work site management system is provided which includes a target sprinkling area setting unit which sets a target sprinkling area in a work area of ​​the work site where a transport vehicle can travel, and a sprinkling path generation unit which calculates an evaluation function including sprinkling evaluation items related to sprinkling by an unmanned sprinkling vehicle and generates a sprinkling path which indicates the target trajectory of the unmanned sprinkling vehicle in the target sprinkling area so as to improve the degree of evaluation value of the evaluation function.

[0007] According to the present disclosure, water can be efficiently sprayed onto a target watering area set in a work area.

[0008] FIG. 1 is a schematic diagram showing a work site according to an embodiment. FIG. 2 is a perspective view showing an unmanned watering vehicle according to an embodiment. FIG. 3 is a schematic diagram showing a work site management system according to an embodiment. FIG. 4 is a block diagram showing a management device according to an embodiment. FIG. 5 is a schematic diagram for explaining a target watering area and watering data according to an embodiment. FIG. 6 is a diagram for explaining a watering path according to an embodiment. FIG. 7 is a diagram for explaining the priority of weight values ​​according to an embodiment. FIG. 8 is a diagram for explaining trajectory segments according to an embodiment. FIG. 9 is a flowchart showing a watering path generation method according to an embodiment. FIG. 10 is a schematic diagram for explaining a first process according to an embodiment. FIG. 11 is a diagram showing an example of a watering path generated by the watering path generation method according to an embodiment. FIG. 12 is a diagram for explaining the watering path generation method according to an embodiment. FIG. 13 is a diagram for explaining the watering path generation method according to an embodiment.

[0009] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings, but the present disclosure is not limited to the embodiments. The components of the embodiments described below can be combined as appropriate. In addition, some components may not be used.

[0010] [Worksite] FIG. 1 is a schematic diagram showing a worksite 1 according to an embodiment. In the embodiment, the worksite 1 is a mine. A mine refers to a place or business where minerals are mined. Examples of mines include a metal mine where metals are mined, a non-metal mine where limestone is mined, and a coal mine where coal is mined. A plurality of unmanned vehicles operate at the worksite 1. An unmanned vehicle refers to a work vehicle that operates unmanned without being operated by a driver. In the embodiment, the unmanned vehicles operating at the worksite 1 include an unmanned transport vehicle 2 and an unmanned watering vehicle 3.

[0011] The unmanned guided vehicle 2 travels unmanned at the work site 1 to transport cargo. In this embodiment, the unmanned guided vehicle 2 is an unmanned dump truck. An example of the cargo transported by the unmanned guided vehicle 2 is excavated material excavated at the work site 1. The unmanned water sprinkler vehicle 3 travels unmanned at the work site 1 to sprinkle water. In this embodiment, the unmanned water sprinkler vehicle 3 is an unmanned water sprinkler truck. The unmanned water sprinkler vehicle 3 sprinkles water to prevent dust or sand from spreading at the work site 1.

[0012] The work site 1 is provided with a work area 4 and a travel path 5. The work area 4 includes at least one of a loading area 4A and an earth unloading area 4B. The loading area 4A is an area where loading work is carried out, in which a loader 6 loads cargo onto an unmanned guided vehicle 2. The loader 6 operates in the loading area 4A. An example of the loader 6 is a hydraulic excavator. The earth unloading area 4B is an area where earth unloading work is carried out, in which an unmanned guided vehicle 2 unloads cargo. The travel path 5 is an area where unmanned vehicles travel towards the work area 4. The travel path 5 is provided to connect at least the loading area 4A and the earth unloading area 4B.

[0013] The unmanned guided vehicle 2 travels through the work site 1 according to a transport path generated by a management device 8, as disclosed in, for example, WO 2022 / 209192. The unmanned water sprinkler vehicle 3 travels through the work site 1 according to a water sprinkler path generated by a management device 8, as disclosed in, for example, WO 2022 / 209192.

[0014] [Sprinkler vehicle] Figure 2 is a perspective view showing an unmanned watering vehicle 3 according to an embodiment. As shown in Figure 2, the unmanned watering vehicle 3 has a vehicle body 3A, a traveling device 3B, a tank 3C, and a watering sprayer 3D. The vehicle body 3A includes a vehicle body frame. The vehicle body 3A is supported by the traveling device 3B. The vehicle body 3A supports the tank 3C. The traveling device 3B includes wheels, tires attached to the wheels, an engine, a brake device, and a steering device. The tank 3C is a member that stores water for sprinkling. At least a portion of the tank 3C is disposed above the vehicle body 3A. The watering sprayer 3D sprays water from the tank 3C. The watering sprayer 3D is disposed at the rear of the tank 3C. The watering sprayer 3D sprinkles water toward the rear of the unmanned watering vehicle 3. In the embodiment, a plurality of watering sprayers 3D are provided. The multiple water sprinkler sprayers 3D are arranged at the rear of the tank 3C at intervals in the vehicle width direction of the unmanned water sprinkler vehicle 3. The vehicle width direction refers to a direction parallel to the rotation axis of the wheels when the unmanned water sprinkler vehicle 3 is traveling straight.

[0015] [Management System] Fig. 3 is a schematic diagram showing a management system 7 of a work site 1 according to an embodiment. The management system 7 includes a management device 8 and a communication system 9. The management device 8 is arranged outside the unmanned guided vehicle 2 and the unmanned water sprinkler vehicle 3. The management device 8 is installed in a control facility 10 of the work site 1. The management device 8 manages the work site 1. An administrator resides in the control facility 10. The management device 8 manages each of the unmanned guided vehicle 2 and the unmanned water sprinkler vehicle 3. Examples of the communication system 9 include the Internet, a mobile phone communication network, a satellite communication network, or a local area network (LAN). The management device 8 communicates wirelessly with each of the unmanned guided vehicle 2 and the unmanned water sprinkler vehicle 3 via the communication system 9.

[0016] 4 is a block diagram showing a management device 8 according to an embodiment. The management device 8 includes a computer 11, an input device 12, and a display device 13. The computer 11 includes a processor 14, a storage device 15, a communication interface 16, and an input / output interface 17.

[0017] The processor 14 includes a CPU (Central Processing Unit). The processor 14 may also include a GPU (Graphics Processing Unit). The storage device 15 includes a recording medium on which computer programs and data are recorded so as to be readable by the processor 14. The storage device 15 includes a system memory such as a RAM (Random Access Memory) or a ROM (Read Only Memory), and an auxiliary storage device. Examples of the auxiliary storage device include a hard disk or a semiconductor memory.

[0018] The communication interface 16 communicates via the communication system 9. The processor 14 communicates with the on-board controller 3E of the unmanned watering vehicle 3 via the communication interface 16 and the communication system 9. The processor 14 is connected to each of the input device 12 and the display device 13 via an input / output interface 17.

[0019] The input device 12 generates input data when operated by an administrator. The administrator can input the input data to the computer 11 by operating the input device 12. Examples of the input device 12 include a touch panel, a computer keyboard, and a voice input device. The input data generated by the input device 12 is sent to the computer 11.

[0020] The display device 13 provides display data to the administrator. The display device 13 displays the display data transmitted from the computer 11. The display device 13 is exemplified by a flat panel display such as a liquid crystal display or an organic EL display.

[0021] Processor 14 has an input unit 21, a target watering area setting unit 22, a watering data generation unit 23, and an output unit 24. Input unit 21, target watering area setting unit 22, watering data generation unit 23, and output unit 24 each include a computer program, algorithm, and data executed by processor 14.

[0022] The input unit 21 acquires input data from the input device 12. The target watering area setting unit 22 sets a target watering area 30 in the work area 4 of the work site 1 where the unmanned guided vehicle 2 can travel, based on the input data. The watering data generation unit 23 generates watering data that indicates the operating conditions of the unmanned watering vehicle 3 in the target watering area 30. The output unit 24 outputs a signal for displaying the watering data generated by the watering data generation unit 23 on the display device 13. The output unit 24 outputs the watering data generated by the watering data generation unit 23 to the communication interface 16, and transmits it to the on-board controller 3E via the communication interface 16.

[0023] FIG. 5 is a schematic diagram illustrating the target watering area 30 and watering data according to the embodiment. The target watering area setting unit 22 sets the target watering area 30 in the work area 4. The target watering area 30 is set inside the work area 4. The size of the target watering area 30 is smaller than the size of the work area 4. The target watering area setting unit 22 can set the target watering area 30 based on the transportation path of the unmanned guided vehicle 2 set in the work area 4. The target watering area setting unit 22 can set the target watering area 30 based on the external shape data of the work area 4. The administrator of the control facility 10 can input the target watering area 30 into the computer 11 by operating the input device 12. The input unit 21 acquires input data indicating the target watering area 30 from the input device 12. The target watering area setting unit 22 can set the target watering area 30 based on the input data acquired by the input unit 21.

[0024] The watering data generation unit 23 generates watering data indicating the operating conditions of the unmanned watering vehicle 3 in the work area 4. The watering data of the unmanned watering vehicle 3 includes driving data indicating the driving conditions of the unmanned watering vehicle 3. The watering data of the unmanned watering vehicle 3 includes the operating conditions of the water sprayers 3D. The watering data of the unmanned watering vehicle 3 may include at least one of the timing to start sprinkling water from the water sprayers 3D, the timing to stop sprinkling water from the water sprayers 3D, and the amount of water sprayed from the water sprayers 3D. If the unmanned watering vehicle 3 is provided with multiple water sprayers 3D, the watering data of the unmanned watering vehicle 3 may include the number of water sprayers 3D that will perform watering.

[0025] The travel data of the unmanned watering vehicle 3 includes the target position, target orientation, target travel speed, and watering path 40 of the unmanned watering vehicle 3. The watering path 40 is a virtual line that indicates the target trajectory of the unmanned watering vehicle 3. The watering path 40 is defined by a trajectory that passes through multiple travel points 40P. Each of the multiple travel points 40P indicates the target position of the unmanned watering vehicle 3. A target orientation and target travel speed of the unmanned watering vehicle 3 are set for each of the multiple travel points 40P. The target position of the unmanned watering vehicle 3 refers to the target position of the unmanned watering vehicle 3 when passing through the travel point 40P. The target orientation of the unmanned watering vehicle 3 refers to the target orientation of the unmanned watering vehicle 3 when passing through the travel point 40P. The target travel speed of the unmanned watering vehicle 3 refers to the target travel speed of the unmanned watering vehicle 3 when passing through the travel point 40P. The watering path 40 is also set on the travel path 5. The unmanned water sprinkler vehicle 3 travels through the work site 1 according to a water sprinkler path 40.

[0026] The watering data generation unit 23 also sets an entrance 41 and an exit 42 in the work area 4. The entrance 41 is the point where the unmanned watering vehicle 3 enters the work area 4 from the travel path 5. The exit 42 is the point where the unmanned watering vehicle 3 exits the work area 4 onto the travel path 5. The entrance 41 and the exit 42 are each set at the boundary between the work area 4 and the travel path 5.

[0027] [Conditions that the watering path must satisfy] Figure 6 is a diagram for explaining the watering path 40 according to the embodiment. The target watering area 30 is set inside the work area 4. The area through which the unmanned watering vehicle 3 passes while spraying water becomes the actual watering area 31 where water is actually sprayed. The unpassed area through which the unmanned watering vehicle 3 does not pass becomes the unwatered area 32 where water is not sprayed.

[0028] The unmanned sprinkler vehicle 3 travels on the ground of the work area 4. The unmanned sprinkler vehicle 3 sprinkles water as it moves forward on the ground of the work area 4. The water sprayer 3D sprinkles water on the ground behind the unmanned sprinkler vehicle 3. The actual sprinkler area 31 is defined based on the footprint 33 of the unmanned sprinkler vehicle 3. The footprint 33 refers to the area passed by the unmanned sprinkler vehicle 3 or the area sprayed with water from the water sprayer 3D of the unmanned sprinkler vehicle 3. The width of the footprint 33 may be considered the vehicle width of the unmanned sprinkler vehicle 3 or the spray width. The vehicle width of the unmanned sprinkler vehicle 3 refers to the dimension of the unmanned sprinkler vehicle 3 in the vehicle width direction. The spray width refers to the dimension of the spray area of ​​water sprayed onto the ground from the water sprayer 3D in the vehicle width direction. The spray width is larger than the vehicle width of the unmanned sprinkler vehicle 3. The footprint 33 may be regarded as the area through which the unmanned water sprinkler vehicle 3 has passed, or as the area over which water has been sprayed onto the ground from the water sprinkler sprayer 3D.

[0029] The watering path 40 is generated so that the unmanned watering vehicle 3 sprays water on a target watering area 30 set in the work area 4. The unmanned watering vehicle 3 travels according to the watering path 40 set in the target watering area 30. The watering path 40 is generated so that the unmanned watering vehicle 3 enters the work area 4 from an entrance 41. The watering path 40 is generated so that the starting point 40S of the watering path 40 coincides with the entrance 41 of the work area 4.

[0030] There is a bank or cliff around the work area 4. Neither the unmanned transport vehicle 2 nor the unmanned watering vehicle 3 can travel outside the work area 4. Therefore, the watering path 40 needs to be generated so that the unmanned watering vehicle 3 does not deviate outside the work area 4. If an obstacle 35 is present in the target watering area 30, the watering path 40 needs to be generated so that the unmanned watering vehicle 3 does not come into contact with the obstacle 35.

[0031] The watering path 40 needs to be generated so that the unmanned watering vehicle 3 can travel stably. In other words, the watering path 40 needs to be generated based on the travel performance of the unmanned watering vehicle 3. For example, the curvature of the watering path 40 needs to be equal to or less than the maximum curvature of the unmanned watering vehicle 3. The maximum curvature of the unmanned watering vehicle 3 refers to the curvature of the circle drawn when the unmanned watering vehicle 3 turns with the minimum turning radius. In addition, the rate of change in curvature of the watering path 40 needs to be equal to or less than the maximum rate of change in curvature of the unmanned watering vehicle 3.

[0032] The smaller the curvature of the watering path 40, the more preferable. The smaller the curvature change rate of the watering path 40, the more preferable. The shorter the length of the watering path 40, the more preferable. When the curvature of the watering path 40 is small and the curvature change rate of the watering path 40 is small, the unmanned watering vehicle 3 can travel through the target watering area 30 at a high driving speed. When the length of the watering path 40 is short, the unmanned watering vehicle 3 can spray water on the target watering area 30 in a short time.

[0033] The watering path 40 is preferably generated so as to reduce the area of ​​the unwatered area 32. The watering path 40 is preferably generated so as to reduce the area of ​​the overlapping area 34, which is watered at least twice in the target watering area 30. In other words, the watering path 40 is preferably generated so that the unmanned watering vehicle 3 can evenly water the target watering area 30. In other words, the watering path 40 is preferably generated so that the unmanned watering vehicle 3 can efficiently water the target watering area 30.

[0034] The watering path 40 is preferably generated so as to reduce the area of ​​the deviation watering area 36 where water is sprayed outside the target watering area 30. In other words, the watering path 40 is preferably generated so that the unmanned watering vehicle 3 does not spray water in areas where watering is not required.

[0035] The closer the position of the unmanned watering vehicle 3 at the end point 40E of the watering path 40 is to the exit 42 of the work area 4, the more preferable it is. The more the orientation of the unmanned watering vehicle 3 at the end point 40E of the watering path 40 is directed toward the exit 42 of the work area 4, the more preferable it is.

[0036] [Evaluation Function] In the embodiment, the watering data generation unit 23 calculates an evaluation function E that includes a watering evaluation item related to the watering of the unmanned watering vehicle 3, a shape evaluation item related to the shape of the target trajectory, an end point evaluation item related to the end point 40E of the target trajectory, and a non-travelable area area evaluation item related to the amount of deviation of the unmanned watering vehicle 3 into the non-travelable area, and generates a watering path 40 that indicates the target trajectory of the unmanned watering vehicle 3 in the target watering area 30 so as to improve the degree of evaluation value of the evaluation function E. The evaluation function E is expressed by the following equation (1).

[0037]

[0038] The multiple evaluation items on the right side of equation (1) are expressed by the following equations (2) to (10).

[0039]

[0040] Equations (2), (3), and (4) represent shape evaluation items related to the shape of the target trajectory. Equations (5), (6), and (7) represent water sprinkling evaluation items related to the water sprinkling of the unmanned water sprinkler vehicle 3. Equation (8) represents a non-traveling area area evaluation item related to the entry area of ​​the unmanned water sprinkler vehicle 3 into a non-traveling area. Equations (9) and (10) represent end point evaluation items related to the end point 40E of the target trajectory.

[0041] Equation (2) is a penalty term indicating an evaluation item in which the smaller the curvature of the target trajectory, the better the degree of the evaluation value. The curvature of the target trajectory must be equal to or less than the maximum curvature of the unmanned water sprinkler vehicle 3. In equation (2), w ０ is a weight value, κ [rad / m] is the curvature of the target trajectory, and κ ｍａｘ [rad / m] is the maximum curvature of the unmanned water sprinkler vehicle 3, and ∫ds is the total length of the target trajectory.

[0042] Equation (3) is a penalty term indicating an evaluation item in which the smaller the curvature change rate of the target trajectory, the better the degree of the evaluation value. The curvature change rate of the target trajectory must be equal to or less than the maximum curvature change rate of the unmanned water sprinkler vehicle 3. In equation (3), w １ is the weight value, and κ′ [rad / m ２ ] is the curvature change rate of the target trajectory, and κ' ｍａｘ [rad / m ２ ] is the maximum curvature change rate of the unmanned water sprinkler vehicle 3, and ∫ds is the total length of the target trajectory.

[0043] Equation (4) is a penalty term indicating an evaluation item in which the shorter the length of the target trajectory, the better the evaluation value. ２ is the weight value, and L ｍａｘ [m] is the upper limit of the length of the target trajectory, and ∫ds is the total length of the target trajectory.

[0044] Equation (5) is a penalty term indicating an evaluation item in which the smaller the area of ​​the overlapping area 34 that has been watered at least twice in the target watering area 30, the better the evaluation value. ３ is the weight value, and S ｓｆ [m ２ ] is the area of ​​the overlapping area 34 (self-intersection area), and S ｔｊ [m ２ ] is the area of ​​the footprint 33 of the unmanned water sprinkler vehicle 3.

[0045] Equation (6) is a penalty term indicating an evaluation item in which the degree of evaluation value increases as the area of ​​the deviation watering area 36 where water is sprayed outside the target watering area 30 becomes smaller. In equation (6), w ４ is the weight value, and S ｏｓ [m２ ] is the area of ​​the deviation watering area 36, ​​and S ｔｊ [m ２ ] is the area of ​​the footprint 33 of the unmanned water sprinkler vehicle 3.

[0046] Equation (7) is a penalty term indicating an evaluation item in which the degree of evaluation value improves as the area of ​​the non-watered area 32 that is not watered in the target watering area 30 becomes smaller. ５ is the weight value, and S ｒｅｍ [m ２ ] is the area of ​​the unwatered area 32, and S ｓｐ [m ２ ] is the area of ​​the target watering area 30.

[0047] Equation (8) is a penalty term indicating an evaluation item whose evaluation value increases as the entry area of ​​the unmanned watering vehicle 3 into the prohibited area decreases. The prohibited area is an area where the unmanned watering vehicle 3 cannot travel. The entry area of ​​the unmanned watering vehicle 3 into the prohibited area includes a work area deviation area indicating the area where the unmanned watering vehicle 3 deviates from the work area 4, and an obstacle overlap area indicating the area where the unmanned watering vehicle 3 overlaps with the obstacle 35. In other words, equation (8) is a penalty term indicating an evaluation item whose evaluation value increases as the area of ​​the prohibited area, which indicates the sum of the area where the unmanned watering vehicle 3 deviates from the work area 4 and the area where the unmanned watering vehicle 3 overlaps with the obstacle 35, decreases. In equation (8), w ６ is the weight value, and S ｏｗ [m ２ ] is the work area deviation area, and S ｏｂ [m ２ ] is the obstacle overlap area, and S ｔｊ [m ２ ] is the area of ​​the footprint 33 of the unmanned water sprinkler vehicle 3.

[0048] Equation (9) is a penalty term indicating an evaluation item in which the degree of the evaluation value improves as the orientation of the unmanned water sprinkler vehicle 3 at the end point 40E of the target trajectory faces the exit 42 of the work area 4. In equation (9), w ７ is the weight value, and v ｅ [m] is the direction of the unmanned water sprinkler vehicle 3 at the end point 40E, and v ｇ[m] is the direction from the end point 40E to the exit 42.

[0049] Equation (10) is a penalty term indicating an evaluation item in which the degree of the evaluation value improves as the position of the unmanned water sprinkler vehicle 3 at the end point 40E of the target trajectory is closer to the exit 42 of the work area 4. In equation (10), w ８ is the weight value, and L ｇ [m] is the distance between the end point 40E and the exit 42, and L ｍｐ [m] is the maximum distance of the work area 4.

[0050] In addition, in equations (5), (6), and (8), the footprint 33 may be considered as the passing area through which the unmanned watering vehicle 3 has passed, or as the spraying area of ​​water sprayed onto the ground from the watering spray 3D.

[0051] In an embodiment, an improvement in the degree of the evaluation value of the evaluation function E means that the evaluation value of the evaluation function E becomes smaller. In an embodiment, a specified value for the evaluation value of the evaluation function E is set. The specified value is a predetermined value. An improvement in the degree of the evaluation value of the evaluation function E means that the evaluation value approaches the specified value. An improvement in the degree of the evaluation value of the evaluation function E means that the difference between the evaluation value and the specified value becomes smaller. In an embodiment, the solution of the watering path 40 is optimized so that the evaluation value of the evaluation function E becomes equal to or less than the specified value. When the evaluation value of the evaluation function E becomes equal to or less than the specified value, it is determined that the solution of the watering path 40 has reached the appropriate standard.

[0052] Note that improving the degree of the evaluation value of the evaluation function E may also mean that the evaluation value of the evaluation function E becomes larger. By changing the sign of the evaluation function E, it is meant that the larger the evaluation value of the evaluation function E, the better the degree of the evaluation value of the evaluation function.

[0053] In determining whether the solution for watering path 40 has reached the appropriate standard, the solution for watering path 40 may be determined to have reached the appropriate standard if, for example, the value of at least one of the multiple evaluation items of evaluation function E shown in equations (2) to (10) is equal to or less than a specified value. For example, the solution for watering path 40 may be determined to have reached the appropriate standard if the area of ​​unwatered area 32 is equal to or less than a predetermined specified area (for example, equal to or less than 30%).

[0054] 7 is a diagram illustrating the priority order of weight values ​​according to the embodiment. ６ is the largest, and the weight value w ６ Next, the weight value w ５ is large, and the weight value w ５ Next, the weight value w ０ , weight value w １ , weight value w ７ , and weight value w ８ is large, and the weight value w ２ , weight value w ３ , and weight value w ４ is the smallest.

[0055] That is, when generating the watering path 40, the evaluation item with the highest priority is whether the unmanned watering vehicle 3 does not deviate from the work area 4 or come into contact with the obstacle 35.

[0056] [Trajectory Segments] The watering data generation unit 23 connects a plurality of trajectory segments to generate the watering path 40. In the embodiment, the trajectory segments include clothoid curves and circular arc curves.

[0057] FIG. 8 is a diagram illustrating trajectory segments according to an embodiment. As shown in FIG. 8, the trajectory segments include a clothoid curve and an arc curve. A clothoid curve is a curve whose curvature changes in proportion to the curve length. An arc curve is a curve whose curvature is constant regardless of the curve length. The watering data generation unit 23 generates a watering path 40 by connecting multiple trajectory segments so that the curvature of the target trajectory does not exceed the maximum curvature of the unmanned watering vehicle 3 and the rate of change of the curvature of the target trajectory does not exceed the maximum curvature change rate of the unmanned watering vehicle 3.

[0058] 9 is a flowchart showing a method for generating a watering path 40 according to an embodiment. In this embodiment, to generate the watering path 40, the watering data generator 23 performs a first process SA in which an evaluation function E is calculated that does not include a watering evaluation item, a shape evaluation item, or an end point evaluation item, but includes only an impassable area area evaluation item, thereby optimizing a solution for the watering path 40 in which the area of ​​the impassable area is zero. After the first process SA, the watering data generator 23 performs a second process SB in which the solution for the watering path 40 is optimized to improve the degree of the evaluation function that includes the watering evaluation item, the shape evaluation item, the end point evaluation item, and the impassable area area evaluation item.

[0059] In the first process SA, the water spray data generating unit 23 calculates the weight value w of the evaluation function E shown in equation (1). １ , weight value w ２ , weight value w ３ , weight value w ４ , weight value w ５ , weight value w ７ , and weight value w ８ is set to zero, and the weight value w ６ is set to a number greater than zero. That is, the watering data generating unit 23 sets the right side of the evaluation function E to only the penalty term shown in equation (8). In the following description, the penalty term shown in equation (8) will be referred to as the no-travel area area penalty term, as appropriate.

[0060] In the first process SA, the watering data generation unit 23 determines the number of trajectory segments and then generates an initial trajectory 40T (step S1). The initial trajectory 40T is generated to have an arbitrary shape. The watering data generation unit 23 generates the initial trajectory 40T by assigning parameters to each of the multiple trajectory segments, for example, using random numbers.

[0061] After the initial trajectory 40T is generated, the watering data generating unit 23 calculates an evaluation function E including only the impassable area area penalty term, and generates the watering path 40 (step S2).

[0062] The water sprinkling data generating unit 23 determines whether the unmanned water sprinkling vehicle 3 traveling according to the water sprinkling path 40 generated in step S2 will deviate from the work area 4 (step S3).

[0063] If it is determined in step S3 that the deviation of the unmanned watering vehicle 3 from the work area 4 has not been resolved (step S3: No), the watering data generation unit 23 changes the solution of the watering path 40 so as to improve the degree of the evaluation value of the evaluation function E (step S4). In the embodiment, the watering data generation unit 23 changes the solution of the watering path 40 so as to decrease the evaluation value of the evaluation function E. After changing the solution of the watering path 40, the watering data generation unit 23 calculates the evaluation function E (step S2).

[0064] The watering data generation unit 23 uses an arbitrary optimization method to change the solution of the watering path 40 so as to reduce the evaluation value of the evaluation function E. As an example, the watering data generation unit 23 uses a differential evolution method to change the solution of the watering path 40 so as to reduce the evaluation value of the evaluation function E.

[0065] The water sprinkling data generating unit 23 repeats the processes of steps S2, S3, and S4 until the deviation of the unmanned water sprinkling vehicle 3 from the work area 4 is resolved.

[0066] FIG. 10 is a schematic diagram illustrating a first process SA according to an embodiment. As shown in FIG. 10 , the watering data generation unit 23 generates an initial trajectory 40T passing through the entrance 41, for example, using random numbers. As shown in the left diagram of FIG. 10 , in step S1, at least a portion of the initial trajectory 40T may deviate outside the work area 4. As shown in the center and right diagrams of FIG. 10 , by repeating the processes of steps S2, S3, and S4, the deviation of the initial trajectory 40T from the work area 4 gradually decreases, and eventually the deviation of the initial trajectory 40T from the work area 4 becomes zero. The watering data generation unit 23 repeats the processes of steps S2, S3, and S4 until the area of ​​the area where the unmanned watering vehicle 3 traveling along the initial trajectory 40T cannot travel becomes zero.

[0067] If it is determined in step S3 that the deviation of the unmanned watering vehicle 3 from the work area 4 has been resolved (step S3: Yes), the second process SB is started. If it is determined in step S3 that the deviation of the unmanned watering vehicle 3 from the work area 4 has been resolved (step S3: Yes), the watering data generator 23 calculates an evaluation function E including all penalty terms (step S5).

[0068] That is, the water spray data generating unit 23 determines the weight value w of the evaluation function E shown in equation (1) in accordance with the priority order of the weight values ​​described with reference to FIG. １ , weight value w ２ , weight value w ３ , weight value w ４ , weight value w ５ , weight value w ６ , weight value w ７ , and weight value w ８ The water spray data generating unit 23 calculates an evaluation function E including all of the multiple penalty terms shown in equation (1) to generate the water spray path 40.

[0069] The water spray data generating unit 23 determines whether the evaluation value of the evaluation function E is equal to or less than a predetermined specified value (step S6).

[0070] In step S6, it may be determined whether the value of at least one of the multiple evaluation items of the evaluation function E shown in equations (2) to (10) is equal to or less than a specified value. For example, it may be determined whether the area of ​​the unwatered area 32 is equal to or less than a predetermined specified area (for example, equal to or less than 30%).

[0071] If it is determined in step S6 that the evaluation value of the evaluation function E is not equal to or less than the specified value (step S6: No), the watering data generator 23 determines whether the number of repetitions of the second process SB is equal to or greater than a predetermined threshold (step S7). The number of repetitions refers to the number of times the processes of steps S5, S6, S7, and S8 are repeated.

[0072] If it is determined in step S7 that the number of repetitions is not equal to or greater than the threshold value (step S7: No), the watering data generator 23 changes the solution of the watering path 40 so as to reduce the evaluation value of the evaluation function E (step S8). After changing the solution of the watering path 40, the watering data generator 23 calculates the evaluation function E (step S5).

[0073] The watering data generation unit 23 uses an arbitrary optimization method to change the solution of the watering path 40 so as to reduce the evaluation value of the evaluation function E. As an example, the watering data generation unit 23 uses a differential evolution method to change the solution of the watering path 40 so as to reduce the evaluation value of the evaluation function E.

[0074] The water spray data generating unit 23 repeats the processes of steps S5, S6, S7, and S8 until the evaluation value of the evaluation function E becomes equal to or less than the specified value.

[0075] If it is determined in step S6 that the evaluation value of the evaluation function E is equal to or less than the specified value (step S6: Yes), the watering data generation unit 23 determines that the solution for the watering path 40 has met the appropriateness criterion, and terminates the second process SB. The output unit 24 displays the watering path 40 that has met the appropriateness criterion on the display device 13 or transmits it to the unmanned watering vehicle 3. The on-board controller 3E of the unmanned watering vehicle 3 controls the unmanned watering vehicle 3 based on the watering data including the watering path 40. The unmanned watering vehicle 3 sprays water while traveling through the target watering area 30 according to the watering path 40 that has met the appropriateness criterion.

[0076] If it is determined in step S7 that the number of repetitions is equal to or greater than the threshold value (step S7: Yes), the watering data generation unit 23 determines that a solution for a watering path 40 that meets the appropriateness criteria cannot be calculated, and terminates the second process SB. The output unit 24 causes the display device 13 to display display data indicating that a watering path 40 that meets the appropriateness criteria has not been calculated. If a solution for a watering path 40 that meets the appropriateness criteria cannot be calculated, the administrator can, for example, redefine the target watering area 30 or adjust the size or shape of the work area 4 so that a watering path 40 that meets the appropriateness criteria is calculated. Note that a watering path 40 that does not meet the appropriateness criteria may be used.

[0077] FIG. 11 is a diagram showing an example of a watering path 40 generated by a method for generating a watering path 40 according to an embodiment. As shown in FIG. 11 , the watering path 40 is generated so that the entrance 41 of the work area 4 coincides with the starting point 40S. The watering path 40 is generated so that the unmanned watering vehicle 3 traveling according to the watering path 40 does not deviate from the work area 4. The watering path 40 is generated so that the unmanned watering vehicle 3 traveling according to the watering path 40 does not come into contact with an obstacle 35. The watering path 40 is generated so that the unwatered area 32 in the target watering area 30 is reduced. The watering path 40 is generated so that the overlapping area 34 in the target watering area 30 is reduced. The watering path 40 is generated so that the deviated watering area 36 is reduced. The watering path 40 is generated so that the orientation of the unmanned watering vehicle 3 at the end point 40E is toward the exit 42 of the work area 4. The watering path 40 is generated so that the position of the unmanned watering vehicle 3 at the end point 40E is near the exit 42 of the work area 4.

[0078] The watering data generation unit 23 may generate a watering path 40 that causes the unmanned watering vehicle 3 to move backward. The watering data generation unit 23 may generate a watering path 40 that causes the unmanned watering vehicle 3 to switch back, for example. A switch back refers to an operation in which the forward-moving unmanned watering vehicle 3 changes its direction of travel and moves backward to enter a predetermined position. For example, if the target watering area 30 includes an area in which it is difficult for the unmanned watering vehicle 3 to turn while moving forward due to the presence of an obstacle 35, the watering data generation unit 23 may generate a watering path 40 that causes the unmanned watering vehicle 3 to switch back. The watering sprayer 3D is provided at the rear of the unmanned watering vehicle 3, and when the unmanned watering vehicle 3 moves backward, spraying of water from the watering sprayer 3D is stopped. In order to shorten the period during which spraying of water from the watering sprayer 3D is stopped, it is preferable that the length of the watering path 40 that causes the unmanned watering vehicle 3 to move backward is short.

[0079] [Effect] As described above, the management system 7 of the work site 1 according to the embodiment comprises a target sprinkling area setting unit 22 that sets a target sprinkling area 30 in the work area 4 of the work site 1 where the unmanned transport vehicle 2 can travel, and a sprinkling data generation unit 23 that calculates an evaluation function E that includes sprinkling evaluation items related to sprinkling by the unmanned sprinkling vehicle 3, and generates a sprinkling path 40 that indicates the target trajectory of the unmanned sprinkling vehicle 3 in the target sprinkling area 30 so as to improve the degree of evaluation value of the evaluation function E.

[0080] According to the embodiment, the unmanned watering vehicle 3 travels according to the watering path 40, thereby efficiently spraying water over the target watering area 30 set in the work area 4. The unmanned watering vehicle 3 can spray water evenly over the target watering area 30.

[0081] In this embodiment, to generate a watering path 40, the watering data generation unit 23 performs a first process SA in which an evaluation function E is calculated that does not include a watering evaluation item, a shape evaluation item, or an end point evaluation item, but includes only an impassable area area evaluation item, thereby optimizing a solution for the watering path 40 in which the area of ​​the impassable area is zero. After the first process SA, the watering data generation unit 23 performs a second process SB in which the solution for the watering path 40 is optimized to improve the degree of the evaluation function that includes the watering evaluation item, the shape evaluation item, the end point evaluation item, and the impassable area area evaluation item. In the first process SA, the watering data generation unit 23 can generate a watering path 40 that satisfies the evaluation item with the highest priority. After generating a watering path 40 that satisfies the evaluation item with the highest priority, the watering data generation unit 23 can generate a watering path 40 that meets the appropriateness criteria in the second process SB.

[0082] [Other Embodiments] Figures 12 and 13 are diagrams illustrating a method for generating a watering path 40 according to an embodiment. As shown in Figures 12 and 13, the watering data generation unit 23 may divide the target watering area 30 into multiple divided areas and generate a watering path 40 for each of the multiple divided areas. In the example shown in Figures 12 and 13, the target watering area 30 is divided into a first divided area 30A and a second divided area 30B, with a dividing line 37 as the boundary. The watering data generation unit 23 divides the target watering area 30 into multiple divided areas using a shape index called the Compact Ratio. The watering data generation unit 23 divides the target watering area 30 into multiple divided areas so that the shape of each divided area approximates a perfect circle. The first divided area 30A includes an inlet 41. The watering data generation unit 23 generates a watering path 40 in the first divided area 30A as shown in FIG. 12, and then generates a watering path 40 in the second divided area 30B as shown in FIG. 13. The watering path 40 generated in the first divided area 30A leads to the entrance 41 of the work area 4. The watering path 40 generated in the first divided area 30A has a starting point 40S. The watering path 40 generated in the second divided area 30B has an ending point 40E. By connecting the watering path 40 generated in the first divided area 30A and the watering path 40 generated in the second divided area 30B, the watering data generation unit 23 can generate a watering path 40 that allows the unmanned watering vehicle 3 to evenly water the target watering area 30. By dividing the target watering area 30 into a plurality of divided areas, generating a watering path 40 for each of the plurality of divided areas, and connecting the watering paths 40 generated for each of the plurality of divided areas, the computation load of the watering path 40 on the watering data generation unit 23 is reduced. For example, the computation time required to calculate the watering path 40 is shortened.

[0083] In the above-described embodiment, the trajectory segment includes a clothoid curve. When generating the watering path 40 using a clothoid curve, it is difficult for the watering data generation unit 23 to specify the position of the end point 40E so that it coincides with the exit 42. Therefore, as described above, the end point evaluation items shown in equations (9) and (10) are required as evaluation items of the evaluation function E. For example, if the trajectory segment includes a curve other than a clothoid curve, such as a B-spline curve or a Bezier curve, the watering data generation unit 23 can specify the position of the end point 40E so that it coincides with the exit 42. If the position of the end point 40E can be specified so that it coincides with the exit 42, the end point evaluation items shown in equations (9) and (10) as evaluation items of the evaluation function E are unnecessary. If the position of the end point 40E can be specified so that the end point 40E coincides with the exit 42, the evaluation function E may include an evaluation item in which the degree of evaluation value increases the smaller the difference between the orientation of the unmanned watering vehicle 3 at the end point 40E and the target orientation of the unmanned watering vehicle 3 at the travel point 40P set at the exit 42. The travel point 40P set at the exit 42 becomes the starting point of the watering path set on the travel path 5. The watering data generation unit 23 may generate the watering path 40 set in the work area 4 so that the position and orientation of the unmanned watering vehicle 3 at the end point 40E of the watering path 40 set in the work area 4 coincide with the position and orientation of the unmanned watering vehicle 3 at the starting point of the watering path set on the travel path 5.

[0084] In the above-described embodiment, instead of or in addition to the unmanned vehicle, a manned vehicle may be operated at the work site 1. A manned vehicle refers to a work vehicle that operates based on driving operations by a driver. For example, a manned transport vehicle may travel in the work area 4.

[0085] In the above-described embodiment, at least some of the functions of the management device 8 may be provided in the vehicle controller 3E. For example, the vehicle controller 3E may include the target watering area setting unit 22 and the watering data generating unit 23.

[0086] In the above-described embodiment, the input unit 21, the target watering area setting unit 22, the watering data generation unit 23, and the output unit 24 may each be configured as separate hardware (computers).

[0087] 1...work site, 2...unmanned transport vehicle, 3...unmanned water sprinkler vehicle, 3A...vehicle body, 3B...traveling device, 3C...tank, 3D...water sprinkler, 3E...on-board controller, 4...work area, 4A...loading area, 4B...soil removal area, 5...traveling path, 6...loader, 7...management system, 8...management device, 9...communication system, 10...control facility, 11...computer, 12...input device, 13...display device, 14...processor, 15...storage device, 16...communication interface, 17...input / output Interface, 21...input section, 22...target watering area setting section, 23...watering data generation section, 24...output section, 30...target watering area, 30A...first divided area, 30B...second divided area, 31...actual watering area, 32...unwatered area, 33...footprint, 34...overlapping area, 35...obstacle, 36...deviation watering area, 37...division line, 40...watering path, 40S...starting point, 40E...end point, 40P...traveling point, 40T...initial trajectory, 41...entrance, 42...exit.

Claims

1. A work site management system comprising: a target sprinkling area setting unit that sets a target sprinkling area in a work area of ​​a work site where a transport vehicle can travel; and a watering data generation unit that calculates an evaluation function including watering evaluation items related to the sprinkling of water by an unmanned watering vehicle, and generates a watering path that indicates a target trajectory of the unmanned watering vehicle in the target watering area so as to improve the degree of evaluation value of the evaluation function.

2. A work site management system as described in claim 1, wherein the watering evaluation items include evaluation items whose evaluation value improves as the area of ​​the unwatered area in the target watering area becomes smaller.

3. A work site management system as described in claim 1, wherein the watering evaluation items include an evaluation item in which the degree of the evaluation value improves as the area of ​​the overlapping area in the target watering area that has been watered at least twice is smaller.

4. A work site management system as described in claim 1, wherein the watering evaluation items include an evaluation item whose evaluation value becomes higher the smaller the area of ​​the deviation watering area where water is sprayed outside the target watering area.

5. A work site management system as described in claim 1, wherein the evaluation function includes a shape evaluation item related to the shape of the target trajectory, and the shape evaluation item includes at least one of an evaluation item in which the degree of the evaluation value improves as the curvature of the target trajectory is smaller than or equal to the maximum curvature of the unmanned watering vehicle, an evaluation item in which the degree of the evaluation value improves as the rate of change of the curvature of the target trajectory is smaller than or equal to the maximum curvature change rate of the unmanned watering vehicle, and an evaluation item in which the degree of the evaluation value improves as the length of the target trajectory is shorter.

6. A work site management system as described in claim 1, wherein the evaluation function includes an end point evaluation item related to the end point of the target trajectory, and the end point evaluation item includes at least one of an evaluation item whose evaluation value becomes higher the closer the orientation of the unmanned watering vehicle at the end point of the target trajectory is toward the exit of the work area, and an evaluation item whose evaluation value becomes higher the closer the position of the unmanned watering vehicle at the end point of the target trajectory is to the exit of the work area.

7. A work site management system as described in claim 1, wherein the evaluation function includes an impassable area area evaluation item in which the degree of the evaluation value increases as the area of ​​the impassable area, which indicates the sum of the area where the unmanned watering vehicle deviates from the work area and the area where the unmanned watering vehicle overlaps with an obstacle, becomes smaller.

8. A work site management system as described in claim 5, wherein the evaluation function includes an impassable area area evaluation item in which the degree of the evaluation value improves as the area of ​​the impassable area, which indicates the sum of the area where the unmanned watering vehicle deviates from the work area and the area where the unmanned watering vehicle overlaps an obstacle, becomes smaller, and the watering data generation unit calculates the evaluation function which does not include the watering evaluation item and the shape evaluation item but does include the impassable area area evaluation item to optimize the watering path solution in which the area of ​​the impassable area becomes zero, and then optimizes the watering path solution in which the degree of the evaluation function including the watering evaluation item and the shape evaluation item improves.

9. A work site management system according to claim 1, wherein the watering data generation unit divides the target watering area into a plurality of divided areas and generates the watering path for each of the plurality of divided areas.

10. A method for managing a work site, comprising: setting a target sprinkling area in a work area of ​​the work site where a transport vehicle can travel; calculating an evaluation function including sprinkling evaluation items related to sprinkling by an unmanned sprinkler vehicle; and generating a sprinkling path indicating a target trajectory of the unmanned sprinkler vehicle in the target sprinkling area so as to improve the degree of evaluation value of the evaluation function.

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