System including work machine, work machine, and automatic travel control method for work machine

Abstract

This system including a work machine executes automatic work in which a series of work for excavating an object (200) to be excavated and loading the excavated object into an object (300) to be loaded is automated. A wheel loader (1) has a position information acquisition device (112) and an automation controller (100). The position information acquisition device (112) detects a current position (P1) of the wheel loader (1). The automation controller (100) generates, from the current position (P1) of the wheel loader (1) detected by the position information acquisition device (112) and a start position (P2) for starting the automatic work, a travel route (R1) from the current position (P1) to the start position (P2).

Description

System including a work machine, work machine, and automatic travel control method for a work machine

[0001] The present disclosure relates to a system including a work machine, a work machine, and an automatic travel control method for a work machine.

[0002] For example, Japanese Patent Laid-Open Publication No. 10-88625 (Patent Document 1) discloses a wheel loader that can automatically perform a series of operations from excavation, to approaching the dump truck for loading, and loading the dump truck.

[0003] Japanese Patent Application Publication No. 10-88625

[0004] When starting an automated operation that automates a series of tasks, it is necessary to accurately position a work machine such as a wheel loader at the starting position (initial position). Positioning manually (including by remote control) is a cumbersome task.

[0005] An object of the present disclosure is to provide a system including a work machine that automatically moves to a start position for automatic work, a work machine, and an automatic travel control method for a work machine.

[0006] A system including a work machine according to the present disclosure performs an automated operation that automates a series of operations, including excavating an excavation target and loading the excavated material into a loading target, and includes a position information sensor and a controller. The position information sensor detects the current position of the work machine. The controller generates a travel route from the current position to the start position based on the current position of the work machine detected by the position information sensor and a start position for starting the automated operation.

[0007] A construction machine disclosed herein performs an automated operation that automates a series of operations, including excavating an excavation target and loading the excavated material into a loading target. The construction machine disclosed herein includes a position information sensor and a controller. The position information sensor detects the current position of the construction machine. The controller calculates a start position for starting the automated operation, and generates a travel route from the current position to the start position based on the current position of the construction machine detected by the position information sensor and the calculated start position.

[0008] The presently disclosed method for controlling automatic travel of a construction machine executes an automatic operation that automates a series of operations, including excavating an excavation target and loading the excavated material into a loading target. The presently disclosed method for controlling automatic travel of a construction machine includes the following steps.

[0009] The current position of the work machine is detected. A start position for starting the automated work is calculated. A travel route from the current position to the start position is generated based on the acquired current position of the work machine and the calculated start position.

[0010] According to the present disclosure, it is possible to realize a system including a work machine that automatically moves to a start position for automatic work, a work machine, and an automatic travel control method for a work machine.

[0011] Fig. 2 is a side view of a wheel loader as an example of a work machine. Fig. 3 is a plan view of the wheel loader shown in Fig. 1. Fig. 4 is a diagram illustrating excavation and loading work by a wheel loader. Fig. 5 is a block diagram showing a schematic configuration of a control system for a wheel loader. Fig. 6 is a block diagram showing a configuration of an automatic travel control system for a wheel loader. Fig. 7 is a schematic diagram showing a travel route of a wheel loader to a start position for automatic work. Fig. 8 is a first flowchart showing an automatic travel control method for a wheel loader. Fig. 9 is a second flowchart showing an automatic travel control method for a wheel loader.

[0012] Hereinafter, the embodiments will be described with reference to the drawings. In the following description, the same parts and components are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed descriptions thereof will not be repeated. It is also intended from the beginning that any configuration may be extracted from the embodiments and arbitrarily combined.

[0013] <Overall configuration of wheel loader 1> In the embodiment, a wheel loader 1 will be described as an example of a work machine. Fig. 1 is a side view of the wheel loader 1 as an example of a work machine. Fig. 2 is a plan view of the wheel loader 1 shown in Fig. 1.

[0014] 1 and 2 , the wheel loader 1 mainly comprises a vehicle frame 2, a work implement 3, a traveling device 4, and a cab 5. The vehicle frame 2, the cab 5, etc. make up the vehicle body of the wheel loader 1. The work implement 3 and the traveling device 4 are attached to the vehicle body of the wheel loader 1. The main body of the wheel loader 1 comprises the vehicle body and the traveling device 4.

[0015] The traveling device 4 allows the body of the wheel loader 1 to travel, and includes traveling wheels 4a, 4b. The wheel loader 1 is a wheeled vehicle that has traveling wheels 4a, 4b on both the left and right sides of the body as rotating bodies for traveling. The wheel loader 1 is self-propelled by driving the traveling wheels 4a, 4b to rotate, and can perform desired work using the work implement 3. The traveling device 4 corresponds to an example of a "traveling body".

[0016] In this specification, the direction in which the wheel loader 1 travels straight ahead is referred to as the fore-and-aft direction of the wheel loader 1. In the fore-and-aft direction of the wheel loader 1, the side on which the work implement 3 is arranged relative to the body frame 2 is referred to as the front direction, and the side opposite the front direction is referred to as the rear direction. The left-and-right direction of the wheel loader 1 is the direction perpendicular to the fore-and-aft direction when the wheel loader 1 is viewed from above on flat ground. The right and left sides of the left-and-right direction when looking forward are the right direction and the left direction, respectively. The up-and-down direction of the wheel loader 1 is the direction perpendicular to the plane defined by the fore-and-aft direction and the left-and-right direction. In the up-and-down direction, the side with ground is the bottom side, and the side with sky is the top side.

[0017] The vehicle body frame 2 includes a front frame 2 a and a rear frame 2 b. The front frame 2 a is disposed in front of the rear frame 2 b. The front frame 2 a and the rear frame 2 b are attached to each other by a center pin 10 so as to be movable relative to each other in the left-right direction.

[0018] A pair of left and right steering cylinders 11 are attached across the front frame 2a and the rear frame 2b. The steering cylinders 11 are hydraulic cylinders. The steering cylinders 11 are extended and retracted by hydraulic oil from a steering pump (not shown), thereby changing the direction of travel of the wheel loader 1 to the left and right. The front frame 2a and the rear frame 2b make up a body frame 2 with an articulated structure. The wheel loader 1 is an articulated work machine in which the front frame 2a and the rear frame 2b are connected so that they can be flexibly moved.

[0019] A work implement 3 and a pair of running wheels (front wheels) 4a are attached to the front frame 2a. The work implement 3 is attached to the front of the body of the wheel loader 1. The work implement 3 is supported by the body of the wheel loader 1. Specifically, the work implement 3 is rotatably supported by the body frame 2, more particularly by the front frame 2a. The work implement 3 is disposed in front of the body frame 2.

[0020] The work implement 3 includes a boom 14. The base end of the boom 14 is rotatably attached to the front frame 2a by a boom pin 9. The boom 14 includes a left boom member 14L and a right boom member 14R. The left boom member 14L and the right boom member 14R are joined by a joining member extending in the left-right direction so as not to move relative to each other, forming the boom 14 of an integral structure. The boom pin 9 includes a pair of left and right boom pins, a left boom pin 9L and a right boom pin 9R. The boom 14 is rotatable relative to the front frame 2a around the left boom pin 9L and the right boom pin 9R as rotation centers. The left boom pin 9L and the right boom pin 9R support the work implement 3 rotatably relative to the body frame 2.

[0021] The work implement 3 includes a bucket 6. The bucket 6 is disposed at the tip of the work implement 3. The bucket 6 is a work tool for excavating and loading. The cutting edge 6a is the tip of the bucket 6. The back surface 6b is part of the outer surface of the bucket 6. The back surface 6b is formed as a flat surface. The back surface 6b extends rearward from the cutting edge 6a. The bucket 6 is rotatably attached to the boom 14 by a bucket pin 17 located at the tip of the boom 14. The bucket 6 has a left boom attachment portion to which the left boom member 14L is attached, and a right boom attachment portion to which the right boom member 14R is attached.

[0022] The work implement 3 further includes a bell crank 18 and a link 15. The bell crank 18 is rotatably supported at its approximate center on the boom 14 by a support pin 18a located approximately in the longitudinal center of the boom 14. The link 15 is connected to a connecting pin 18c provided at the lower end (tip) of the bell crank 18. The link 15 connects the bell crank 18 and the bucket 6. The bell crank 18 and the link 15 are disposed between the left boom member 14L and the right boom member 14R in the left-right direction.

[0023] The front frame 2a and the boom 14 are connected by a pair of boom cylinders 16. The boom cylinders 16 are hydraulic cylinders. The boom cylinders 16 rotate the boom 14 up and down around the boom pin 9. The base end of the boom cylinder 16 is attached to the front frame 2a. The tip of the boom cylinder 16 is attached to the boom 14. The boom cylinder 16 is a hydraulic actuator that moves the boom 14 up and down relative to the front frame 2a. As the boom 14 moves up and down, the bucket 6 attached to the tip of the boom 14 also moves up and down.

[0024] The bucket cylinder 19 connects the bell crank 18 and the front frame 2a. The base end of the bucket cylinder 19 is attached to the front frame 2a. The tip of the bucket cylinder 19 is attached to a connecting pin 18b provided at the upper end (base end) of the bell crank 18. The bucket cylinder 19 is a hydraulic actuator that rotates the bucket 6 up and down relative to the boom 14. The bucket cylinder 19 is an implement cylinder that drives the bucket 6. The bucket cylinder 19 drives the bucket 6 to rotate around the bucket pin 17. The bucket 6 is configured to be movable relative to the boom 14. The bucket 6 is configured to be movable relative to the front frame 2a.

[0025] The boom cylinder 16 and the bucket cylinder 19 constitute a work implement actuator that drives the work implement 3 .

[0026] A cab 5 in which the operator sits and a pair of running wheels (rear wheels) 4b are attached to the rear frame 2b. The box-shaped cab 5 is located behind the boom 14. The cab 5 is mounted on the rear frame 2b. The cab 5 is placed on the body frame 2. Inside the cab 5, a seat in which the operator of the wheel loader 1 sits, an operating device 8 (FIG. 4) described below, and the like are arranged.

[0027] The cab 5 is provided with a perception device 111. The perception device 111 is disposed, for example, on the ceiling of the cab 5. The perception device 111 is mounted, for example, on the top surface of the cab 5. The perception device 111 is disposed, for example, in the front of the cab 5. The perception device 111 is attached to the cab 5 facing forward, for example, and is capable of acquiring information about the area in front of the cab 5. Details of the perception device 111 will be described later.

[0028] Length L1 shown in Fig. 1 is the length from the cutting edge 6a of the bucket 6 to the rear end of the vehicle body in the front-to-rear direction (total length of the wheel loader 1). Length L2 is the length from the front end of the front wheel 4a to the rear end of the vehicle body in the front-to-rear direction (vehicle body length of the wheel loader 1). Length L3 is the length from the center of the front wheel 4a to the center of the rear wheel 4b in the front-to-rear direction (wheelbase length). Length L4 is the length from the center of the front wheel 4a to the bending center between the front frame 2a and the rear frame 2b in the front-to-rear direction. Length L5 is the length from the bending center between the front frame 2a and the rear frame 2b to the center of the rear wheel 4b in the front-to-rear direction.

[0029] 2 is the length (bucket width) from the left end to the right end of the bucket 6. The center point 6c of the bucket 6 in the width direction is the center point of the bucket 6 in the left-right direction.

[0030] The lengths L1 to L5 and L9 shown in Figures 1 and 2 are included in the specification values ​​of the wheel loader 1. The specification values ​​of the wheel loader 1 also include the minimum turning radius of the vehicle body. The wheel loader 1 has an articulated structure in which the front frame 2a and rear frame 2b can bend relative to each other, which reduces the minimum turning radius of the vehicle body compared to a rigid structure. The specification values ​​of the wheel loader 1 are unique to each individual wheel loader 1 and are stored in the vehicle body controller 50, which will be described later.

[0031] <Excavation and Loading Work> The wheel loader 1 of this embodiment performs excavation and loading work by scooping excavated material into the bucket 6 and loading the excavated material in the bucket 6 into a loading target 300 such as a dump truck. The excavated material is earth, sand, rocks, ore, etc. that has been excavated at a work site or transported to the work site by a transport machine such as a dump truck. Figure 3 is a diagram illustrating excavation and loading work performed by the wheel loader 1 based on this embodiment.

[0032] Figure 3(A) shows the wheel loader 1 moving forward empty. The wheel loader 1 travels forward toward an excavation target 200, which is a pile of excavated material. The boom cylinder 16 and bucket cylinder 19 (Figure 1) operate so that the work implement 3 assumes an excavation posture with the tip of the boom 14 in a low position and the bucket 6 facing horizontally.

[0033] Figures 3(B) and (C) show the wheel loader 1 performing an excavation operation. The wheel loader 1 plunges the cutting edge 6a of the bucket 6 into the excavation target 200 and stops forward travel. The excavation (plunging) operation shown in Figure 3(B) causes the cutting edge 6a of the bucket 6 to dig into the excavation target 200. In this state, the boom 14 and the bucket 6 are raised and the bucket 6 tilts back, causing the bucket 6 to move along the bucket trajectory BL as indicated by the arrow in Figure 3(C). This operation performs an excavation (scooping) operation in which the excavation target 200 is excavated and the excavated material is scooped into the bucket 6, as shown in Figure 3(C).

[0034] Depending on the type of excavation target 200, the excavation (scooping) operation may be completed by tilting back the bucket 6 once. Alternatively, the excavation (scooping) operation may involve repeating the operation of tilting back the bucket 6, returning it to a neutral position, and tilting it back again.

[0035] 3(D) shows the wheel loader 1 moving backward with a load. The wheel loader 1 moves backward with excavated material loaded in the bucket 6. The wheel loader 1 may raise the bucket 6 while moving backward.

[0036] 3(E) shows the wheel loader 1 moving forward with a load. The wheel loader 1 moves forward toward the object to be loaded 300 while raising the bucket 6 or while maintaining the bucket 6 in a raised state. The wheel loader 1 approaches the object to be loaded 300 until the bucket 6 reaches a predetermined position located almost directly above the bed of the object to be loaded 300.

[0037] Figure 3(F) shows the wheel loader 1 performing an earth discharging operation onto the loading target 300. When the wheel loader 1 approaches the loading target 300 and reaches a predetermined position, it dumps the bucket 6 and loads the excavated material in the bucket 6 onto the loading target 300. The wheel loader 1 then moves backward to the position where it started forward travel in Figure 3(E), while lowering the boom 14 to return the work implement 3 to the excavation position.

[0038] The above is a typical operation that constitutes one cycle of excavation and loading work. The wheel loader 1 repeats the above-described operations in sequence to excavate the excavation target 200 and load the excavated material onto the loading target 300, such as a dump truck.

[0039] When the wheel loader 1 excavates the excavation target 200 shown in Figures 3(B) and 3(C), the front frame 2a and the rear frame 2b are in a straight-advance position without bending relative to each other. When the wheel loader 1 loads the excavated material in the bucket 6 onto the loading target 300 shown in Figure 3(F), the front frame 2a and the rear frame 2b are in a straight-advance position without bending relative to each other.

[0040] <System Configuration> FIG. 4 is a block diagram showing the schematic configuration of a control system that controls the wheel loader 1.

[0041] 4, the engine 21 is a drive source, such as a diesel engine, that generates drive power for driving the work implement 3 and the traveling device 4. Instead of the engine 21, a motor driven by an electricity storage device may be used as the drive source, or both the engine and the motor may be used. The output of the engine 21 is controlled by adjusting the amount of fuel injected into the cylinders of the engine 21.

[0042] The driving force generated by the engine 21 is transmitted to the transmission (T / M) 23. The transmission 23 changes the driving force to an appropriate torque and rotational speed. An axle 25 is connected to the output shaft of the transmission 23. The driving force changed by the transmission 23 is transmitted to the axle 25. The driving force is transmitted from the axle 25 to the running wheels 4a, 4b (FIGS. 1 and 2). This causes the wheel loader 1 to travel. In the wheel loader 1 of this embodiment, both the running wheels 4a and 4b constitute driving wheels that receive the driving force and cause the wheel loader 1 to travel.

[0043] A portion of the driving force of the engine 21 is transmitted to the work implement pump 13. The work implement pump 13 is a hydraulic pump that is driven by the engine 21 and operates the work implement 3 by the hydraulic oil that it discharges. The work implement 3 is driven by the hydraulic oil from the work implement pump 13. The hydraulic oil discharged from the work implement pump 13 is supplied to the boom cylinder 16 and the bucket cylinder 19 via a main valve 32. The boom cylinder 16 receives the supply of hydraulic oil and extends and contracts, thereby raising and lowering the boom 14. The bucket cylinder 19 receives the supply of hydraulic oil and extends and contracts, thereby rotating the bucket 6 up and down.

[0044] The wheel loader 1 is equipped with a vehicle body controller 50. The vehicle body controller 50 includes an engine controller 60, a transmission controller 70, and a work machine controller 80.

[0045] The vehicle body controller 50 is generally implemented by reading various programs using a CPU (Central Processing Unit). The vehicle body controller 50 has a memory (not shown). The memory functions as a work memory and stores various programs for implementing the functions of the wheel loader 1.

[0046] The operating device 8 is provided in the cab 5. The operating device 8 is operated by an operator. The operating device 8 is equipped with a plurality of types of operating members that the operator operates to operate the wheel loader 1. The operating device 8 includes an accelerator pedal 41 and a work implement operating lever 42. The operating device 8 may also include a steering handle, a shift lever, etc., which are not shown.

[0047] The accelerator pedal 41 is operated to set a target rotation speed of the engine 21. The engine controller 60 controls the output of the engine 21 based on the amount of operation of the accelerator pedal 41. When the amount of operation (depression amount) of the accelerator pedal 41 is increased, the output of the engine 21 increases. When the amount of operation of the accelerator pedal 41 is decreased, the output of the engine 21 decreases. The transmission controller 70 controls the transmission 23 based on the amount of operation of the accelerator pedal 41.

[0048] The work implement control lever 42 is operated to operate the work implement 3. The work implement controller 80 controls the electromagnetic proportional control valves 35, 36 based on the amount of operation of the work implement control lever 42.

[0049] The electromagnetic proportional control valve 35 switches the main valve 32 so that the bucket cylinder 19 retracts and the bucket 6 moves in the dump direction (the direction in which the cutting edge of the bucket 6 moves down). The electromagnetic proportional control valve 35 also switches the main valve 32 so that the bucket cylinder 19 extends and the bucket 6 moves in the tilt direction (the direction in which the cutting edge of the bucket 6 moves up). The electromagnetic proportional control valve 36 switches the main valve 32 so that the boom cylinder 16 retracts and the boom 14 moves down. The electromagnetic proportional control valve 36 also switches the main valve 32 so that the boom cylinder 16 extends and the boom 14 moves up.

[0050] The machine monitor 51 displays various types of information upon receiving command signals as input from the vehicle body controller 50. The various types of information displayed on the machine monitor 51 may be, for example, information relating to the work performed by the wheel loader 1, vehicle body information such as the remaining fuel amount, coolant temperature, and hydraulic oil temperature, and peripheral images captured of the area around the wheel loader 1. The machine monitor 51 may be a touch panel, and in this case, a signal generated when the operator touches a part of the machine monitor 51 is output from the machine monitor 51 to the vehicle body controller 50.

[0051] <Automatic Travel Control System for Wheel Loader 1> There is a demand for the wheel loader 1 to automatically travel to a start position for an automatic operation that automates the series of operations shown in Fig. 3. Fig. 5 is a block diagram showing the configuration of an automatic travel control system for the wheel loader 1.

[0052] As shown in Fig. 5, the automation controller 100 is configured to be able to send and receive signals to and from the vehicle body controller 50 described using Fig. 4. The automation controller 100 is also configured to be able to receive signals from an external environment information acquisition unit 110. The external environment information acquisition unit 110 has a perception device 111 and a position information acquisition device 112. The perception device 111 and the position information acquisition device 112 are mounted on the wheel loader 1.

[0053] The perception device 111 acquires information about the surroundings of the wheel loader 1. The perception device 111 is attached, for example, to the front part of the top surface of the cab 5. The perception device 111 corresponds to an example of an "object sensor" that detects objects around the main body of the wheel loader 1.

[0054] The perception device 111 detects the direction of an object outside the wheel loader 1 and the distance to the object in a non-contact manner. The perception device 111 is, for example, a LiDAR (Light Detection and Ranging) device that emits laser light to acquire information about the object. The perception device 111 may also be a visual sensor including a camera. The perception device 111 may also be a Radar (Radio Detection and Ranging) device that acquires information about the object by emitting radio waves. The perception device 111 may also be an infrared sensor.

[0055] The position information acquisition device 112 acquires information about the current position of the wheel loader 1. The position information acquisition device 112, for example, uses a satellite positioning system to acquire position information of the wheel loader 1 in a global coordinate system based on the Earth. The position information acquisition device 112, for example, uses GNSS (Global Navigation Satellite Systems) and has a GNSS receiver. The satellite positioning system calculates the position of the GNSS receiver antenna based on positioning signals received by the GNSS receiver from satellites, thereby calculating the position of the wheel loader 1. The perception device 111 and the position information acquisition device 112 each correspond to an example of a "position information sensor" that detects the current position of the wheel loader 1.

[0056] The external environment information of the wheel loader 1 obtained by the perception device 111 and the position information of the wheel loader 1 obtained by the position information acquisition device 112 are input to the automation controller 100 .

[0057] The vehicle body controller 50 is configured to be able to receive signals from the vehicle information acquisition unit 120, and receives input of information about the wheel loader 1 acquired by the vehicle information acquisition unit 120. The vehicle information acquisition unit 120 is made up of various sensors mounted on the wheel loader 1. The vehicle information acquisition unit 120 has an articulation angle sensor 121, a vehicle speed sensor 122, a boom angle sensor 123, a bucket angle sensor 124, and a boom cylinder pressure sensor 125.

[0058] The articulation angle sensor 121 detects the articulation angle, which is the angle between the front frame 2 a and the rear frame 2 b, and generates a signal of the detected articulation angle. The articulation angle sensor 121 outputs the signal of the articulation angle to the vehicle body controller 50.

[0059] The vehicle speed sensor 122 detects the travel speed of the wheel loader 1 caused by the traveling device 4, for example, by detecting the rotational speed of the output shaft of the transmission 23, and generates a signal of the detected vehicle speed. The vehicle speed sensor 122 outputs the vehicle speed signal to the vehicle body controller 50. The vehicle speed sensor 122 corresponds to an example of a travel sensor that detects the progress of the traveling device 4 (traveling body).

[0060] The boom angle sensor 123 is configured, for example, by a rotary encoder provided on the boom pin 9, which is the attachment portion of the boom 14 to the body frame 2. The boom angle sensor 123 detects the angle (boom angle) of the boom 14 with respect to the horizontal direction, and generates a signal of the detected angle of the boom 14. The boom angle sensor 123 outputs the signal of the angle of the boom 14 to the body controller 50.

[0061] Bucket angle sensor 124 is configured, for example, by a rotary encoder provided on support pin 18a, which is the rotation axis of bell crank 18. Bucket angle sensor 124 detects the angle of bell crank 18 relative to boom 14 (bell crank angle) and generates a signal of the detected angle of bell crank 18. Vehicle information acquisition unit 120 or vehicle body controller 50 calculates the angle of bucket 6 relative to boom 14 (bucket angle) from the detected angle of bell crank 18.

[0062] The boom angle sensor 123 and the bucket angle sensor 124 correspond to an example of a work implement attitude sensor that detects the attitude of the work implement 3. The boom angle sensor 123 may be a stroke sensor arranged in the boom cylinder 16. The bucket angle sensor 124 may be a potentiometer or a proximity switch attached to the bucket pin 17, or may be a stroke sensor arranged in the bucket cylinder 19.

[0063] Boom cylinder pressure sensor 125 detects the pressure on the bottom side of boom cylinder 16 (boom bottom pressure) and generates a signal of the detected boom bottom pressure. The boom bottom pressure increases when bucket 6 is loaded and decreases when bucket 6 is empty. Boom cylinder pressure sensor 125 outputs the boom bottom pressure signal to vehicle body controller 50.

[0064] The vehicle body controller 50 outputs the information input from the vehicle information acquisition unit 120 to the automation controller 100. The automation controller 100 receives detection values ​​from the articulation angle sensor 121, the vehicle speed sensor 122, etc. via the vehicle body controller 50.

[0065] The actuator 140 is configured to be able to receive signals from the vehicle body controller 50. The actuator 140 is driven in response to command signals from the vehicle body controller 50. The actuator 140 includes a brake EPC (electromagnetic proportional control valve) 141 for actuating the brakes of the traveling device 4, a steering EPC 142 for adjusting the traveling direction of the wheel loader 1, a work implement EPC 143 for operating the work implement 3, and an HMT (hydraulic mechanical transmission) 144.

[0066] The electromagnetic proportional control valves 35, 36 shown in Fig. 4 constitute a work machine EPC 143. The transmission 23 shown in Fig. 4 is realized as an HMT 144 that utilizes electronic control. The transmission 23 may be a hydrostatic transmission (HST). The power transmission device that transmits power from the engine 21 to the running wheels 4a, 4b may include an electric drive device such as a diesel-electric system, or may include any combination of an HMT, an HST, and an electric drive device.

[0067] The transmission controller 70 has a brake control unit 71 and an accelerator control unit 72. The brake control unit 71 outputs a command signal to the brake EPC 141 to control the operation of the brakes. The accelerator control unit 72 outputs a command signal to the HMT 144 to control the vehicle speed.

[0068] The work machine controller 80 has a steering control section 81 and a work machine control section 82. The steering control section 81 outputs a command signal to the steering EPC 142 to control the traveling direction of the wheel loader 1. The work machine control section 82 outputs a command signal to the work machine EPC 143 to control the operation of the work machine 3.

[0069] The automation controller 100 includes a current position estimation unit 101 , a target position setting unit 102 , a path generation unit 103 , and a path following control unit 104 .

[0070] The current position estimation unit 101 estimates the current position of the wheel loader 1 based on information acquired by the external environment information acquisition unit 110. Specifically, the current position estimation unit 101 estimates the current position P1 ( FIG. 6 ) of the wheel loader 1 based on positioning signals received from satellites by a GNSS receiver, which is an example of the position information acquisition device 112, or detection signals from a LiDAR, which is an example of the perception device 111. The current position estimation unit 101 may create a highly accurate surrounding map using data acquired by the LiDAR, and estimate its own position by comparing the surrounding map with a pre-stored map (SLAM: Simultaneous Localization and Mapping).

[0071] The target position setting unit 102 sets a target position based on the external environment information acquired by the external environment information acquisition unit 110. The target position is, for example, a start position P2 ( FIG. 6 ) of an automated operation that automates the series of operations shown in FIG. 3 . The target position is, for example, an excavation position in the excavation target 200 where the wheel loader 1 excavates the excavation target 200 with the bucket 6. The target position is, for example, a loading area P3 ( FIG. 6 ) in the loading target 300, which is the relative position of the work implement 3 (bucket 6) with respect to the loading target 300 when loading excavated materials into the loading target 300. For example, the perception device 111 may recognize each of the target positions and input them to the automation controller 100, or the target position setting unit 102 may set the target positions based on the detection results detected by the perception device 111.

[0072] The path generation unit 103 generates an optimum path for the wheel loader 1 when the wheel loader 1 travels automatically. As shown in Fig. 6, the path generation unit 103 generates a travel path R1 as an optimum path connecting the current position P1 of the wheel loader 1 that has entered the work area WA and the start position P2 of the automatic work. Furthermore, as shown in Fig. 6, the path generation unit 103 generates a travel path R2 as an optimum path connecting the current position of the wheel loader 1 and a target position to which the wheel loader 1 is heading while excavation and loading work is being performed. The travel path R2 has a V-shape, for example, for V-shaped travel.

[0073] The path generating unit 103 generates the following path as the travel path R2. For example, the path generating unit 103 generates a path for travel of the wheel loader 1 moving forward empty toward the excavation target 200. The path generating unit 103 generates a path for the operation of the work implement 3 during excavation work. The path generating unit 103 generates a path for travel of the wheel loader 1 moving backward empty and away from the excavation target 200, and a path for the operation of the work implement 3 while moving backward empty. The path generating unit 103 generates a path for travel of the wheel loader 1 moving forward empty toward the loading target 300, and a path for the operation of the work implement 3 while moving forward empty. The path generating unit 103 generates a path for the operation of the work implement 3 that unloads the excavated material scooped into the bucket 6 onto the loading target 300. The path generating unit 103 generates a path for travel of the wheel loader 1 moving backward empty and away from the loading target 300, and a path for the operation of the work implement 3 while moving backward empty.

[0074] The path generation unit 103 also generates a travel path R1 from the current position P1 of the wheel loader 1 at the time it enters the work area WA to a start position P2 of the automatic work. When generating the travel path R1, the path generation unit 103 recognizes, for example, the position of the center pin 10 of the wheel loader 1 at the time it enters the work area as the current position P1. The current position P1 is acquired by the perception device 111 or the position information acquisition device 112. The path generation unit 103 also recognizes a start position P2 of the automatic work based on a relative positional relationship with the excavation target 200. The path generation unit 103 may also recognize the start position P2 based on a relative positional relationship with both the excavation target 200 and the loading target 300. The path generation unit 103 may also recognize the start position P2 based on the travel path R2 generated as described above.

[0075] The work area WA (the area surrounded by a dashed line in FIG. 6) is set as a substantially rectangular area that encompasses, in a top view, the area through which the wheel loader 1 travels to perform the series of operations shown in FIG. 3, for example. The work area WA also includes, for example, a loading area P3 for the excavation target 200 and the loading target 300. Coordinate information for the work area WA may be stored in advance in, for example, the automation controller 100, or may be acquired by the external environment information acquisition unit 110.

[0076] The path following control unit 104 commands the operation of the traveling device 4 and the work machine 3. The path following control unit 104 controls the accelerator, brake, and steering so that the wheel loader 1 travels by following the optimal route generated by the path generation unit 103. The path following control unit 104 outputs a command signal to the brake control unit 71, accelerator control unit 72, and steering control unit 81 to cause the wheel loader 1 to travel along the optimal route. The path following control unit 104 controls the boom cylinder 16 and bucket cylinder 19 so that the work machine 3 operates along the optimal route generated by the path generation unit 103. The path following control unit 104 outputs a command signal to the work machine control unit 82 to cause the work machine 3 to move along the optimal route. The path following control unit 104 enables the wheel loader 1 to travel by following the travel routes R1, R2.

[0077] The wheel loader 1 may be remotely operated by an operator using an external operation device 350. The wheel loader 1 and operation device 350 have communication devices 150, 310 for communicating with each other. The communication device 150 of the wheel loader 1 has a receiving unit 150a for receiving remote operation commands from the operation device 350, and a transmitting unit 150b for transmitting operation information and the like of the wheel loader 1 to the operation device 350. On the other hand, the communication device 310 of the operation device 350 has a receiving unit 310a for receiving information transmitted from the transmitting unit 150b of the wheel loader 1, and a transmitting unit 310b for transmitting remote operation commands to the receiving unit 150a of the wheel loader 1.

[0078] In addition to the communication device 310, the operation device 350 has an operation unit 320 that is operated by an operator, and a display unit 330 that displays various information. The operation unit 320 is capable of performing operations, for example, to transition the wheel loader 1 to a state in which automatic traveling is permitted. The operation unit 320 is also capable of performing operations, for example, to cause the wheel loader 1 to start automatic work. The operation unit 320 is also capable of performing operations, for example, to drive the work implements 3 and traveling devices 4 of the wheel loader 1.

[0079] The display unit 330 displays, for example, information relating to work performed by the wheel loader 1, vehicle body information such as the remaining fuel level, coolant temperature and hydraulic oil temperature, and images of the surrounding area of ​​the wheel loader 1. The display unit 330 may be a touch panel, in which case a signal generated when the operator touches a part of the display unit 330 is transmitted from the transmitter 310b to the receiver 150a. In this case, the display unit 330 can function as the operation unit 320.

[0080] The operation device 350 is placed in a remote location away from the wheel loader 1. The operation device 350 may be installed in a location away from the work area WA, may be fixedly installed in the work area WA, may be mounted on a mobile information terminal such as a smartphone or tablet, or may be mounted on the loading target 300.

[0081] The interface 130 is configured to be able to send and receive signals to and from the vehicle body controller 50. The interface 130 has an engine emergency stop switch 131 and a mode lamp 132.

[0082] The engine emergency stop switch 131 is operated by an operator. When an event occurs that requires an emergency stop of the engine 21, the operator operates the engine emergency stop switch 131. A signal indicating the operation of the engine emergency stop switch 131 is input to the vehicle body controller 50.

[0083] The mode lamp 132 indicates whether the wheel loader 1 is currently in a mode where it is manually operated by an operator, or in a mode where it is automatically controlled. A command signal for controlling the lighting of the lamp is output from the vehicle body controller 50 to the mode lamp 132.

[0084] The automation controller 100 is also configured to be able to send and receive signals to and from the communication device 150. The automatic travel control system of the wheel loader 1 is configured so that the automation controller 100 can issue commands to drive various operations of the wheel loader 1 based on information acquired from the communication device 150.

[0085] <Automatic travel control method> A control method for automatically traveling the wheel loader 1 to the start position P2 of the automatic work, which automates the series of work shown in Figure 3, will be described below. Figure 6 is a schematic diagram showing the travel route R1 of the wheel loader to the start position P2 of the automatic work. Figures 7 and 8 are first and second flowcharts, respectively, showing the automatic travel control method for the wheel loader 1.

[0086] The excavation target 200 shown in Figure 6 is a pile of excavated material to be excavated by the bucket 6 of the wheel loader 1. The excavation target 200 may be a pile of excavated material accumulated in a stockyard or other excavation material accumulation area. The excavation target 200 may also be a pile of excavated material formed on a vacant lot. The excavation target 200 has a peak 201, which has the highest peak height, and a base 202 on the front side (the side where the wheel loader 1 excavates the excavation target 200; the lower side in Figure 6). The base 202 is schematically shown as a straight line. The peak height of the excavation target 200 is not uniform, but gradually decreases from the peak 201 to the base 202.

[0087] The excavation target 200 has, near the base 202, a low-mountain region 203 where the amount of excavated material accumulated is small and the mountain height is low, and an accumulation region 204 where the amount of excavated material accumulated is greater than in the low-mountain region 203 and the mountain height is higher than in the low-mountain region 203.

[0088] A loading object 300 such as a dump truck stops at a loading area P3, which is an arbitrary location relative to the excavation object 200. The loading object 300 basically stops at a stopping position that complies with the rules of the work site, but may stop at an arbitrary stopping position that differs from the stopping position that complies with the rules of the work site at the discretion of an operator operating the loading object 300 or at the instruction of a control center monitoring the work site. A dump truck, which is an example of the loading object 300, has a vessel 301 for loading excavated materials.

[0089] 7 , first, in step S11a, the operator issues an instruction to permit automatic traveling to the wheel loader 1. The operator issues the instruction to permit automatic traveling to the wheel loader 1 as a remote control command using, for example, the operation unit 320 of the operation device 350. The instruction to permit automatic traveling sent from the operation device 350 is received by the receiving unit 150a of the communication device 150 and output to the automation controller 100.

[0090] The operator on board the wheel loader 1 may issue an instruction to permit automatic traveling by operating the operation unit of the wheel loader 1. In this case, the instruction to permit automatic traveling is output from the operation unit of the wheel loader 1 to the automation controller 100.

[0091] In step S12a, the automation controller 100 acquires an instruction to permit automatic travel, causing the wheel loader 1 to transition to an automatic travel permitted state. The automatic travel permitted state refers to a state in which automatic travel begins when the automation controller 100 determines that a predetermined condition is met. An example of the predetermined condition is that the wheel loader 1 enters the work area WA.

[0092] In step S13a, the operator manually moves the wheel loader 1 from outside the work area WA to inside the work area WA. The operator manually moves the wheel loader 1 by operating the accelerator, brakes, steering, etc. The manual operation by the operator may be an operation performed by an operator in a remote location away from the wheel loader 1 using the operation device 350, or it may be an operation performed by an operator on board the wheel loader 1.

[0093] In step S14a, it is determined whether or not the reference point of the wheel loader 1 has entered the work area WA. This determination is made by the current position estimation unit 101 of the automation controller 100. The current position estimation unit 101 determines whether or not the reference point of the wheel loader 1 has entered the work area WA based on information acquired from the external environment information acquisition unit 110.

[0094] The information acquired from the external environment information acquisition unit 110 is, for example, a positioning signal received from a satellite by a GNSS receiver, which is an example of the position information acquisition device 112. The information acquired from the external environment information acquisition unit 110 may also be, for example, a detection signal from a LiDAR, which is an example of the perception device 111.

[0095] Furthermore, the reference point of the wheel loader 1 is, for example, the center position of the center pin 10. Therefore, when the current position estimation unit 101 determines that the center position of the center pin 10 has entered the work area WA in a top view, it determines that the wheel loader 1 has entered the work area WA. Coordinate information indicating the work area WA is acquired or stored in advance in the automation controller 100. Furthermore, the reference point may also be the position of the cutting edge 6a of the bucket 6.

[0096] If the current position estimation unit 101 determines in step S14a that the reference point of the wheel loader 1 is not within the work area WA, the movement of the wheel loader 1 continues under manual operation by the operator as shown in step S13a.

[0097] On the other hand, if the current position estimation unit 101 determines in step S14a that the reference point of the wheel loader 1 has entered the work area WA, then in step S15 the path generation unit 103 generates a travel path R1 from the current position P1 to the start position P2 of the wheel loader 1. When generating the travel path R1, the path generation unit 103 acquires the current position P1 and the start position P2.

[0098] The current position P1 is estimated by the current position estimation unit 101 based on positioning signals received from satellites by a GNSS receiver, which is an example of the position information acquisition device 112. The current position P1 may also be estimated by the current position estimation unit 101 using a SLAM technique using a LiDAR, which is an example of the perception device 111. The path generation unit 103 acquires information about the current position P1 from the current position estimation unit 101. The start position P2 is set by the target position setting unit 102 based on a detection signal from the LiDAR, which is an example of the perception device 111. The path generation unit 103 acquires information about the start position P2 from the target position setting unit 102.

[0099] The start position P2 is set based on the relative positional relationship between the wheel loader 1 and the excavation target 200. For example, when the wheel loader 1 is located at the assumed start position P2, the position where the center line CL1 in the left-right direction of the wheel loader 1 is collinear with the center line CL2 of the excavation target 200 is set as the start position P2. Furthermore, when the wheel loader 1 travels straight from the assumed start position P2 towards the excavation target 200, the position where the center point 6c of the cutting edge 6a coincides with the center point Bx of the excavation target 200 is set as the start position P2.

[0100] The start position P2 may be set based on the relative positional relationship between the wheel loader 1 and the excavation target 200 and the loading target 300. For example, as described above, when the center line CL1 of the wheel loader 1 and the center line CL2 of the excavation target 200 are positioned on the same straight line and the wheel loader 1 is positioned at the assumed start position P2, a position where the loading area P3 is included within a range of a viewing angle θ2 of 120° for the operator riding on the wheel loader 1 may be set as the start position P2. The position where the viewing angle θ2 is 120° may be set based on the center of the center pin 10, or may be set at a specific point in the interior space of the cab 5.

[0101] The start position P2 may also be set based on a travel route R2 when an automatic operation (excavation and loading operation) is performed, which is an automated operation of the series of operations shown in Fig. 3. The travel route R2 is generated by the route generation unit 103, for example, as follows.

[0102] When generating the travel route R2, first the excavation location of the excavation target 200 is detected, and a route for loading onto the loading target 300 is generated. Specifically, the perception device 111 mounted on the wheel loader 1 detects the excavation target 200 and the loading target 300. The objects around the wheel loader 1 detected by the perception device 111 include the excavation target 200 and the loading target 300. The perception device 111 inputs the detection results of the excavation target 200 and the loading target 300 to the automation controller 100.

[0103] The target position setting unit 102 recognizes the excavation target 200 and the loading target 300 based on the detection results of the perception device 111. The target position setting unit 102 recognizes the position and shape of the pile of excavated material that is the excavation target 200. The target position setting unit 102 recognizes the position and shape of the loading target 300 (for example, a vessel 301). The target position setting unit 102 recognizes the angle θ1 formed between the base 202 of the excavation target 200 and the left side of the vessel 301.

[0104] The path generation unit 103 of the automation controller 100 recognizes a loading position A1, which is the relative position of the work implement 3 (bucket 6) with respect to the loading object 300, such as a dump truck, when loading excavated material onto the loading object 300.

[0105] The path generation unit 103 calculates the minimum distance x1 that the wheel loader 1 can travel in a V shape from the specification values ​​(including lengths L1 to L5, L9) of the wheel loader 1. V-shaped traveling is a typical traveling path when the wheel loader 1 performs excavation and loading work, and the traveling path of the wheel loader 1 forms a V shape. When the wheel loader 1 travels in a V shape to perform excavation and loading work, the traveling distance of the wheel loader 1 is minimized, and therefore this is considered to be an efficient traveling path.

[0106] The path generating unit 103 sets the position of the base 202 of the excavation target 200 that is a distance x1 away from the loading position A1 in the direction in which the base 202 extends as a tentative excavation position B1. The path generating unit 103 selects an excavation position Bx at a position that is farther from the loading target 300 than the tentative excavation position B1 in the direction in which the base 202 of the excavation target 200 extends.

[0107] The path generating unit 103 generates the shortest path connecting the loading position A1 and the excavation position Bx during V-shaped traveling. The path generating unit 103 can determine a position that is a length L1 away from the foot 202 of the excavation target 200, starting from the excavation position Bx, as the turning back position Tx. The path generating unit 103 can generate a straight path connecting the excavation position Bx and the turning back position Tx as the path for the wheel loader 1 to move forward empty toward the excavation target 200, and as the path for the wheel loader 1 to move backwards with a load away from the excavation target 200. The traveling paths when the wheel loader 1 moves forward empty and when the wheel loader 1 moves backwards with a load are farther away from the loading position A1 than the distance x1.

[0108] The path generating unit 103 can generate a path that combines straight lines and curves with any curvature so that the wheel loader 1, which starts moving forward with the load from the turning back position Tx, will reach the center point 6c of the cutting edge 6a of the bucket 6 at the loading position A1 of the loading target 300, and so that the width direction of the bucket 6 when it reaches the loading position A1 will coincide with the fore-and-aft direction of the loading target 300. The radius of curvature of the curves included in this path is larger than the minimum radius at which the wheel loader 1 can turn without steering, so the wheel loader 1 can move forward from the turning back position Tx to the loading position A1 without steering. The path generating unit 103 can use this generated path as the path for moving forward with the load towards the loading target 300, and as the path for moving backward without the load towards the loading target 300.

[0109] By setting the turning position Tx at a position that is farther away from the loading position A1 than the distance x1, the wheel loader 1, which moves forward with the load from the turning position Tx toward the loading position A1, can align the width direction of the bucket 6 with the fore-and-aft direction of the loading object 300 when the bucket 6 reaches the loading position A1 without having to turn the steering wheel at a fixed angle.

[0110] In this way, a travel path R2 for V-shaped traveling, for example, is generated. When the travel path R2 for V-shaped traveling is generated, a start position P2 for the wheel loader 1 in automatic work is also determined. The start position P2 is determined to be, for example, a position where the position of the center point 6c of the cutting edge 6a of the bucket 6 coincides with the turning position Tx, and where the direction in which the wheel loader 1 travels straight forward coincides with the direction from the turning position Tx toward the excavation position Bx.

[0111] In step S16, once the travel route R1 has been generated as described above, the wheel loader 1 automatically travels along the generated travel route R1. During this automatic travel, the path following control unit 104 commands the operation of the traveling device 4 and the work implement 3. The path following control unit 104 controls the accelerator, brake, and steering so that the wheel loader 1 travels following the travel route R1. The path following control unit 104 outputs command signals to the brake control unit 71, accelerator control unit 72, and steering control unit 81 to cause the wheel loader 1 to travel along the travel route R1.

[0112] In step S17, the wheel loader 1 reaches the start position P2 through the above-described automatic travel, which makes it possible to start the automatic operation that automates the series of operations shown in FIG.

[0113] The automatic travel control in this embodiment is carried out as described above. As a result, when the reference point of the wheel loader 1 enters the work area WA, the travel route R1 is automatically generated and the wheel loader 1 automatically travels from the current position P1 to the start position P2.

[0114] It is also possible to generate a travel route R1 based on an instruction from the operator to start automatic travel, and have the wheel loader 1 automatically travel from the current position P1 to the start position P2. This automatic travel control will be explained using FIG. 8.

[0115] In the automatic travel control shown in Figure 8, in step S11b, the operator manually moves the wheel loader 1 to the work area WA. In step S12b, it is determined whether or not the reference point of the wheel loader 1 has entered the work area WA. These steps S11b and S12b are the same as steps S13a and S14a shown in Figure 7, and therefore their description will not be repeated.

[0116] In step S13b, if the current position estimation unit 101 determines that the reference point of the wheel loader 1 has entered the work area WA, the wheel loader 1 automatically transitions to an automatic driving permitted state. The automatic driving permitted state means a state in which automatic driving begins when the automation controller 100 determines that a predetermined condition has been met. The predetermined condition is, for example, the automation controller 100 receiving an instruction to start automatic driving from the operator.

[0117] In step S14b, after the wheel loader 1 has transitioned to the automatic traveling permitted state, the operator issues an automatic traveling start instruction to the wheel loader 1. The operator issues an automatic traveling start instruction to the wheel loader 1 as a remote control command using, for example, the operation unit 320 of the operation device 350. The automatic traveling start instruction transmitted from the operation device 350 is received by the receiving unit 150a of the communication device 150 and output to the automation controller 100.

[0118] The operator aboard the wheel loader 1 may issue a command to start automatic traveling by operating the operation unit of the wheel loader 1. In this case, the command to start automatic traveling is output from the operation unit of the wheel loader 1 to the automation controller 100.

[0119] Thereafter, steps S15 to S17 are carried out, similar to the control method in Fig. 7. As a result, in this automatic travel control, when the automation controller 100 receives an instruction from the operator to start automatic travel, the travel route R1 is automatically generated and the wheel loader 1 automatically travels from the current position P1 to the start position P2.

[0120] <Functions and Effects> Next, the characteristic configuration and functions and effects of this embodiment will be summarized as follows.

[0121] 5 and 6, according to this embodiment, the automation controller 100 generates a travel route R1 from the current position P1 of the wheel loader 1 detected by the position information acquisition device 112 to the start position P2 for starting the automated work, based on the current position P1 to the start position P2. This makes it possible to automatically move to the start position P2 for the automated work.

[0122] 5, the automation controller 100 controls the traveling device 4 so that the wheel loader 1 automatically travels along the generated traveling route R1. This eliminates the need for manual operation by the operator.

[0123] 5, according to this embodiment, the automation controller 100 generates a travel route R1 based on the determination result that the wheel loader 1 has entered a work area WA in which a series of operations are performed, including excavating the excavation target 200 and loading the excavated material onto a loading target 300. This makes it possible to automatically generate the travel route R1, triggered by the wheel loader 1 entering the work area WA.

[0124] Furthermore, according to this embodiment, as shown in Figure 5, the automation controller 100 transitions the wheel loader 1 to an automatic travel permitted state in which the wheel loader 1 travels automatically along the travel route R1 based on the operation of the operator. This makes it possible to put the wheel loader 1 into the automatic travel permitted state at a timing desired by the operator.

[0125] 5, the automation controller 100 generates a travel route R1 based on an operation by an operator, thereby enabling the generation of the travel route R1 at a timing desired by the operator.

[0126] Furthermore, according to this embodiment, as shown in Figure 5, the automation controller 100 transitions the wheel loader 1 to an automatic travel permitted state in which the wheel loader 1 travels automatically along the travel route R1 based on the determination result that the wheel loader 1 has entered the work area WA. This makes it possible to automatically transition the wheel loader 1 to an automatic travel permitted state, triggered by the wheel loader 1 entering the work area WA.

[0127] Furthermore, according to this embodiment, as shown in Figure 5, the operator operates the wheel loader 1 from a remote location. This makes it possible to operate the wheel loader 1 from a remote location.

[0128] Furthermore, according to this embodiment, as shown in Figure 5, the automation controller 100 generates a travel route R1 that can be traveled without stationary steering. This makes it possible to reduce damage (such as tire wear) that occurs to the wheel loader 1 due to stationary steering.

[0129] The automation controller 100 that constitutes the automatic travel control system for the wheel loader 1 explained in the above embodiment does not necessarily have to be mounted on the wheel loader 1. A controller external to the wheel loader 1 may construct a system that constitutes the automation controller 100. The controller mounted on the wheel loader 1 may perform processing to transmit information acquired by the external environment information acquisition unit 110 and the vehicle information acquisition unit 120, etc., to an external controller, and the external controller that receives the signal may generate a travel route for the wheel loader 1.

[0130] The external controller may be located at the work site of the wheel loader 1, or may be located in a remote location away from the work site of the wheel loader 1. The external controller may be a portable device. The external controller may be a portable device that can be carried and used by an operator, such as a laptop computer, a tablet computer, or a smartphone.

[0131] In the above embodiment, a dump truck is used as an example of the loading object 300, and the operation of loading the excavated material loaded in the work implement 3 (bucket 6) into the vessel 301 has been described. The loading object 300 onto which the excavated material in the bucket 6 is to be loaded is not limited to the vessel 301 of the dump truck, and may be, for example, a hopper.

[0132] In the above embodiment, an example has been described in which the excavation target 200 and the loading target 300 are detected by the perception device 111 mounted on the wheel loader 1. The perception device 111 that detects objects around the main body of the wheel loader 1 does not necessarily have to be mounted on the wheel loader 1. The perception device 111 may also be disposed external to the work machine. For example, the perception device 111 may be disposed at a predetermined point on the work site, may be mounted on another work machine, or may be mounted on an unmanned aerial vehicle such as a drone.

[0133] In the above embodiment, an example has been described in which the wheel loader 1 is equipped with a cab 5 and is a manned vehicle in which an operator rides in the cab 5. The wheel loader 1 may be an unmanned vehicle. The wheel loader 1 does not have to be equipped with a cab 5 for an operator to ride in and operate. The wheel loader 1 does not have to be equipped with a control function by an operator on board. The wheel loader 1 may be a work machine exclusively for remote control. The wheel loader 1 may be controlled by a radio signal from a remote control device.

[0134] <Additional Notes> The above description includes the following additional features.

[0135] (Supplementary Note 1) A system including a work machine that performs an automated operation that automates a series of operations of excavating an excavation target and loading the excavated material into a loading target, the system comprising: a position information sensor that detects the current position of the work machine; and a controller that generates a travel route from the current position of the work machine detected by the position information sensor to a start position for starting the automated operation, based on the current position of the work machine detected by the position information sensor and the start position for starting the automated operation.

[0136] (Supplementary Note 2) The system according to Supplementary Note 1, wherein the work machine has a traveling body, and the controller controls the traveling body so that the work machine automatically travels along the generated travel path.

[0137] (Supplementary Note 3) The system according to Supplementary Note 1 or Supplementary Note 2, wherein the controller generates the travel path based on a determination result that the work machine has entered a work area for performing the series of works.

[0138] (Supplementary Note 4) The system according to Supplementary Note 3, wherein the controller transitions the work machine to an automatic travel permitted state in which the work machine automatically travels along the travel route based on an operation by an operator.

[0139] (Supplementary Note 5) The system according to Supplementary Note 1 or Supplementary Note 2, wherein the controller generates the travel route based on an operation by an operator.

[0140] (Supplementary Note 6) The system described in Supplementary Note 5, wherein the controller transitions the work machine to an automatic driving permitted state in which the work machine automatically travels along the travel route based on a determination result that the work machine has entered a work area for performing the series of tasks.

[0141] (Supplementary Note 7) The system according to Supplementary Note 4 or Supplementary Note 5, wherein the operation by the operator is an operation by an operator from a remote location away from the work machine.

[0142] (Supplementary Note 8) The system according to any one of Supplementary Note 1 to Supplementary Note 7, wherein the controller generates the travel route that can be traveled without stationary steering.

[0143] The embodiments disclosed herein are to be considered in all respects as illustrative and not restrictive. The scope of the present invention is defined not by the above description but by the claims, and it is intended to include all modifications within the meaning and scope of the claims.

[0144] 1 Wheel loader, 2 Body frame, 2a Front frame, 2b Rear frame, 3 Work implement, 4 Traveling device, 4a Front wheel, 4b Rear wheel, 5 Cab, 6 Bucket, 6a Cutting edge, 6b Back, 6c Center point, 8,350 Operating device, 9 Boom pin, 9L Left boom pin, 9R Right boom pin, 10 Center pin, 11 Steering cylinder, 13 Work implement pump, 14 Boom, 14L Left boom member, 14R Right boom member, 15 Link, 16 Boom cylinder, 17 Bucket pin, 18 Bell crank, 18a Support pin, 18b, 18c Connecting pin, 19 Bucket cylinder, 21 Engine, 23 Transmission, 25 Axle, 32 Main valve, 35, 36 Electromagnetic proportional control valve, 41 Accelerator pedal, 42 Work implement operating lever, 50 Vehicle controller, 51 Machine monitor, 60 engine controller, 70 transmission controller, 71 brake control unit, 72 accelerator control unit, 80 work machine controller, 81 steering control unit, 82 work machine control unit, 100 automation controller, 101 current position estimation unit, 102 target position setting unit, 103 path generation unit, 104 path following control unit, 110 external environment information acquisition unit, 111 perception device, 112 position information acquisition device, 120 vehicle information acquisition unit, 121 articulate angle sensor, 122 vehicle speed sensor, 123 boom angle sensor, 124 bucket angle sensor, 125 boom cylinder pressure sensor, 130 interface, 131 engine emergency stop switch, 132 mode lamp, 140 actuator, 141 brake EPC, 142 steering EPC, 143 work machine EPC, 144 HMT, 150, 310 Communication device, 150a, 310a receiving unit, 150b, 310b transmitting unit, 200 excavation target, 201 mountain peak, 202 foothills, 203 low mountain area, 204 accumulation area, 300 loading target, 301 vessel, 320 operation unit, 330 display unit, P1 current position, P2 starting position, P3 loading area, R1, R2 traveling route.

Claims

1. A system including a work machine that performs an automated operation that automates a series of tasks of excavating an excavation target and loading the excavated material into a loading target, the system comprising: a position information sensor that detects the current position of the work machine; and a controller that generates a travel route from the current position of the work machine detected by the position information sensor to a start position for starting the automated operation, based on the current position of the work machine detected by the position information sensor and the start position for starting the automated operation.

2. The system according to claim 1, wherein the work machine has a traveling body, and the controller controls the traveling body so that the work machine automatically travels along the generated travel path.

3. The system according to claim 1, wherein the controller generates the travel route based on a determination result that the work machine has entered a work area for performing the series of tasks.

4. The system according to claim 3, wherein the controller transitions the work machine to an automatic driving permitted state in which the work machine automatically drives along the driving route based on an operation by an operator.

5. The system according to claim 1, wherein the controller generates the travel route based on an operation by an operator.

6. A system as described in claim 5, wherein the controller transitions the work machine to an automatic driving permitted state in which the work machine automatically drives along the driving route based on a determination result that the work machine has entered a work area for performing the series of tasks.

7. The system according to claim 4 or 5, wherein the operation by the operator is performed from a remote location away from the work machine.

8. The system according to claim 1, wherein the controller generates the driving route that can be driven without stationary steering.

9. A work machine that performs automated work by automating a series of tasks, such as excavating an excavation target and loading the excavated material into a loading target, comprising: a position information sensor that detects the current position of the work machine; and a controller that calculates a start position for starting the automated work, and generates a travel route from the current position to the start position based on the current position of the work machine detected by the position information sensor and the calculated start position.

10. An automatic driving control method for a work machine that performs an automatic operation that automates a series of tasks of excavating an excavation target and loading the excavated material into a loading target, the automatic driving control method for a work machine comprising the steps of: detecting the current position of the work machine; calculating a start position for starting the automatic operation; and generating a driving route from the current position to the start position based on the acquired current position of the work machine and the calculated start position.

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