WO2024057959A1

WO2024057959A1 - System including work machine, controller for work machine, and method for controlling work machine

Info

Publication number: WO2024057959A1
Application number: PCT/JP2023/031874
Authority: WO
Inventors: 高史松山
Original assignee: 株式会社小松製作所
Priority date: 2022-09-15
Filing date: 2023-08-31
Publication date: 2024-03-21
Also published as: JP2024042456A

Abstract

This invention is intended to enable automation of loading work into containers of various shapes. This controller for a work machine stores the trajectory of a work implement and a reference point of a container when an operation has been performed by which the work machine loads cargo loaded on the work implement into the container, and when the position of the reference point has been changed, the controller changes the trajectory in accordance with the changed reference point.

Description

Systems including work machines, work machine controllers, and work machine control methods

The present disclosure relates to a system including a work machine, a controller for the work machine, and a method for controlling the work machine.

A conventional wheel loader is disclosed in, for example, International Publication No. 2020/224768 (Patent Document 1).

International Publication 2020/224768

A wheel loader repeatedly performs excavation work and loading work. When automating loading operations, it is required to be able to handle loading into containers of various shapes.

The present disclosure proposes a system including a work machine, a controller for the work machine, and a method for controlling the work machine, which enable automation of loading work into containers of various shapes.

According to an aspect of the present disclosure, a work machine main body, a work machine attached to the work machine main body and having a bucket, a work machine attitude sensor that detects the attitude of the work machine, and an object around the work machine main body are detected. A system is proposed that includes a work machine that includes an object sensor and a controller that communicates with the work machine attitude sensor and the object sensor. The controller stores the trajectory of the work machine and the reference point of the container when the work machine is operated to load the load in the bucket into the container. When the position of the reference point is changed, the controller changes the trajectory according to the changed reference point.

According to an aspect of the present disclosure, a controller for a work machine is proposed. The controller stores the trajectory of the work machine and the reference point of the container when the work machine is operated to load the load loaded on the work machine into the container. When the position of the reference point is changed, the controller changes the trajectory according to the changed reference point.

According to a certain aspect of the present disclosure, a method for controlling a work machine is proposed. The control method is to memorize the trajectory of the work machine and the reference point of the container when the work machine is operated to load the load loaded on the work machine into the container, and to store the position of the reference point. If the reference point is changed, the trajectory is changed according to the changed reference point.

According to the system including the working machine, the controller for the working machine, and the control method for the working machine of the present disclosure, it is possible to automate the loading work into containers of various shapes.

FIG. 1 is a side view of a wheel loader as an example of a working machine. FIG. 1 is a block diagram showing a schematic configuration of a control system for a wheel loader. FIG. 2 is a plan view of a wheel loader that performs excavation and loading work. FIG. 1 is a block diagram showing the configuration of an automatic control system for a wheel loader. 2 is a flowchart showing a process flow for recording work machine control when a skilled operator loads a container. FIG. 3 is a diagram showing the trajectory of a working machine when a skilled operator loads containers. 3 is a flowchart showing the flow of processing for editing recorded parameters. It is a graph showing changes in cylinder length during loading work. FIG. 3 is a diagram schematically showing the attitude of the wheel loader when starting a bucket dumping operation. FIG. 3 is a diagram schematically showing the attitude of the wheel loader when the cutting edge reaches the innermost position. FIG. 3 is a diagram schematically showing the attitude of the wheel loader when stopping the dumping operation of the bucket. It is a figure which shows typically the attitude|position of a wheel loader when stopping the raising operation|movement of a boom. FIG. 3 is a diagram schematically showing the attitude of the wheel loader when starting a bucket tilting operation. It is a figure which shows typically the attitude|position of a wheel loader when stopping the tilting operation of a bucket. 7 is a flowchart showing the flow of a second process for editing parameters. FIG. 3 is a schematic diagram showing feature points corresponding to vessels of different vehicle class. It is a schematic diagram which shows the reference point when changing the loading position of a dump truck. It is a flowchart which shows the flow of the process of loading the load loaded into the bucket into the container by automatic control.

Hereinafter, embodiments will be described based on the drawings. In the following description, the same parts and components are given the same reference numerals. Their names and functions are also the same. Therefore, detailed explanations thereof will not be repeated. It is also planned from the beginning that arbitrary configurations will be extracted from the embodiments and that they will be combined arbitrarily.

<Overall configuration of wheel loader 1>
In the embodiment, a wheel loader 1 will be described as an example of a working machine. FIG. 1 is a side view of a wheel loader 1 as an example of a working machine.

As shown in FIG. 1, the wheel loader 1 includes a vehicle body frame 2, a working machine 3, a traveling device 4, and a cab 5. The vehicle body of the wheel loader 1 is composed of a vehicle body frame 2, a cab 5, and the like. A working machine 3 and a traveling device 4 are attached to the vehicle body of the wheel loader 1. The main body of the wheel loader 1 includes a vehicle body and a traveling device 4.

The traveling device 4 causes the vehicle body of the wheel loader 1 to travel, and includes running

wheels

4a and 4b. The wheel loader 1 is a wheeled vehicle that includes running

wheels

4a and 4b as rotating bodies for running on both sides of the vehicle body in the left-right direction. The wheel loader 1 is self-propelled by rotationally driving running

wheels

4a and 4b, and can perform desired work using the working machine 3. The traveling device 4 corresponds to an example of a traveling object.

In this specification, the direction in which the wheel loader 1 travels straight is referred to as the front-rear direction of the wheel loader 1. In the front-rear direction of the wheel loader 1, the side on which the working machine 3 is arranged with respect to the vehicle body frame 2 is defined as the front direction, and the side opposite to the front direction is defined as the rear direction. The left-right direction of the wheel loader 1 is a direction perpendicular to the front-rear direction when the wheel loader 1 on a flat ground is viewed from above. Looking forward, the right and left sides in the left and right direction are the right direction and left direction, respectively. The vertical direction of the wheel loader 1 is a direction perpendicular to a plane defined by the front-rear direction and the left-right direction. In the vertical direction, the side with the ground is the bottom, and the side with the sky is the top.

The vehicle body frame 2 includes a front frame 2a and a rear frame 2b. The front frame 2a is arranged in front of the rear frame 2b. The front frame 2a and the rear frame 2b are attached to each other so as to be movable in the left-right direction.

A pair of steering cylinders 11 are attached across the front frame 2a and the rear frame 2b. Steering cylinder 11 is a hydraulic cylinder. As the steering cylinder 11 expands and contracts with the hydraulic oil from the steering pump, the direction of movement of the wheel loader 1 is changed from side to side. The front frame 2a and the rear frame 2b constitute a vehicle body frame 2 having an articulated structure. The wheel loader 1 is an articulated working machine in which a front frame 2a and a rear frame 2b are connected for bending movement.

A working machine 3 and a pair of running wheels (front wheels) 4a are attached to the front frame 2a. The work machine 3 is attached to the front of the main body of the wheel loader 1. The work machine 3 is supported by the vehicle body of the wheel loader 1. The work machine 3 includes a boom 14 and a bucket 6. The bucket 6 is arranged at the tip of the working machine 3. The bucket 6 is a working tool for digging 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 of a flat surface. The back surface 6b extends rearward from the cutting edge 6a.

The base end of the boom 14 is rotatably attached to the front frame 2a by a boom pin 9. The bucket 6 is rotatably attached to the boom 14 by a bucket pin 17 located at the tip of the boom 14. The boom pin 9 and the bucket pin 17 correspond to a plurality of joints of the working machine 3.

The work machine 3 further includes a bell crank 18 and a link 15. The bell crank 18 is rotatably supported by the boom 14 by a support pin 18a located approximately at the center of the boom 14. The link 15 is connected to a connecting pin 18c provided at the tip of the bell crank 18. Link 15 connects bell crank 18 and bucket 6.

The front frame 2a and the boom 14 are connected by a pair of boom cylinders 16. Boom cylinder 16 is a hydraulic cylinder. The boom cylinder 16 rotates the boom 14 up and down about the boom pin 9 . A 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 with respect 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.

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 base end of the bell crank 18. The bucket cylinder 19 is a hydraulic actuator that rotates the bucket 6 up and down with respect to the boom 14. Bucket cylinder 19 is a work tool cylinder that drives bucket 6 . Bucket cylinder 19 rotates bucket 6 around bucket pin 17 . Bucket 6 is configured to be movable relative to boom 14 . The bucket 6 is configured to be movable relative to the front frame 2a.

The boom cylinder 16 and the bucket cylinder 19 correspond to an example of a work machine actuator that drives the work machine 3.

A cab 5 on which an operator rides and a pair of running wheels (rear wheels) 4b are attached to the rear frame 2b. A box-shaped cab 5 is arranged behind the boom 14. The cab 5 is placed on the vehicle body frame 2. Inside the cab 5, a seat on which an operator of the wheel loader 1 sits, an operating device 8, which will be described later, and the like are arranged.

The cab 5 is provided with a sensory device 111. The sensory device 111 is arranged, for example, on the ceiling of the cab 5. The sensory device 111 is mounted on the top surface of the cab 5, for example. The sensory device 111 is arranged, for example, at the front of the cab 5. The sensing device 111 is attached to the cab 5, for example, facing forward, and is capable of acquiring information in front of the cab 5. The details of the perception device 111 will be described later.

<System configuration>
FIG. 2 is a block diagram showing a schematic configuration of a control system that controls the wheel loader 1. As shown in FIG.

The engine 21 is a drive source that generates the driving force for driving the work machine 3 and the traveling device 4, and is, for example, a diesel engine. 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 cylinder of the engine 21.

The driving force generated by the engine 21 is transmitted to the transmission 23. The transmission 23 changes the driving force to appropriate torque and rotational speed. An axle 25 is connected to the output shaft of the transmission 23. The driving force shifted by the transmission 23 is transmitted to the axle 25. Driving force is transmitted from the axle 25 to the running

wheels

4a, 4b (FIG. 1). Thereby, the wheel loader 1 travels. In the wheel loader 1 of the embodiment, both the running

wheels

4a and 4b constitute driving wheels that receive driving force and cause the wheel loader 1 to travel.

A part of the driving force of the engine 21 is transmitted to the work equipment pump 13. The work machine pump 13 is a hydraulic pump that is driven by the engine 21 and operates the work machine 3 with the hydraulic fluid it discharges. The work machine 3 is driven by hydraulic oil from a work machine pump 13. Hydraulic oil discharged from the work equipment pump 13 is supplied to the boom cylinder 16 and the bucket cylinder 19 via the main valve 32. The boom 14 moves up and down as the boom cylinder 16 expands and contracts in response to the supply of hydraulic oil. When the bucket cylinder 19 is supplied with hydraulic oil and expands and contracts, the bucket 6 rotates up and down.

The wheel loader 1 includes a vehicle body controller 50. Vehicle controller 50 includes an engine controller 60, a transmission controller 70, and a work equipment controller 80.

The vehicle body controller 50 is generally realized 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 realizing the functions of the wheel loader 1.

The operating device 8 is provided in the cab 5. The operating device 8 is operated by an operator. The operating device 8 includes a plurality of types of operating members that are operated by an operator 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 include a steering handle, a shift lever, etc. (not shown).

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

The work equipment operating lever 42 is operated to operate the work equipment 3. The work machine controller 80 controls the electromagnetic

proportional control valves

35 and 36 based on the amount of operation of the work machine operating lever 42.

The electromagnetic proportional control valve 35 switches the main valve 32 so that the bucket cylinder 19 is retracted and the bucket 6 moves in the dumping direction (the direction in which the cutting edge of the bucket 6 is lowered). Further, the electromagnetic proportional control valve 35 switches the main valve 32 so that the bucket cylinder 19 is extended and the bucket 6 is moved in the tilt direction (the direction in which the cutting edge of the bucket 6 is raised). The electromagnetic proportional control valve 36 switches the main valve 32 so that the boom cylinder 16 is retracted and the boom 14 is lowered. Further, the electromagnetic proportional control valve 36 switches the main valve 32 so that the boom cylinder 16 is extended and the boom 14 is raised.

The machine monitor 51 receives command signals from the vehicle controller 50 and displays various information. The various information displayed on the machine monitor 51 includes, for example, information regarding the work performed by the wheel loader 1, vehicle body information such as remaining fuel level, cooling water temperature, and hydraulic oil temperature, and surrounding images of the surroundings of the wheel loader 1. etc. 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 controller 50.

<Excavation and loading work>
The wheel loader 1 of this embodiment performs an excavation and loading operation in which an excavated object such as earth and sand is scooped up and the excavated object is loaded onto a loading object such as a dump truck. FIG. 3 is a plan view of the wheel loader 1 that performs excavation and loading work. FIG. 3 shows a wheel loader 1 that performs a so-called V-shape operation.

FIG. 3(A) shows a wheel loader 1 that moves forward with a so-called empty load. The wheel loader 1 travels forward along an excavation route R1 toward an excavation target 310 such as earth and sand. The wheel loader 1 thrusts the bucket 6 into the excavated object 310 and stops moving forward. By raising the bucket 6 with the cutting edge 6a of the bucket 6 biting into the excavated object 310, an excavation operation in which the excavated object 310 is scooped into the bucket 6 is executed.

FIG. 3(B) shows a wheel loader 1 that performs so-called backward movement with a loaded load. An excavated object 310 is loaded into the bucket 6 . The wheel loader 1 travels backward along the excavation route R1 to the position where forward travel is started in FIG. 3(A).

FIG. 3(C) shows a wheel loader 1 that advances a load. With the excavated object 310 loaded in the bucket 6, the wheel loader 1 moves forward toward the vessel 301 of the dump truck 300. The wheel loader 1 moves forward from the position where it starts moving forward in FIG. 3(A) toward the dump truck 300 along the loading route R2. When approaching the dump truck 300 and reaching a predetermined position, the wheel loader 1 loads the excavated object 310 in the bucket 6 into the vessel 301. The vessel 301 corresponds to an example of a "container" for loading a load loaded onto the work machine 3.

FIG. 3(D) shows a wheel loader 1 that moves backward with no load. When the excavated object 310 in the bucket 6 is completely discharged into the vessel 301 of the dump truck 300 and the bucket 6 is empty, the wheel loader 1 loads the object to the position where it starts moving forward in FIG. 3(C). Travel backwards along route R2.

In this way, the wheel loader 1 can repeatedly perform a series of operations such as excavation, retreat, dump approach, earth removal, and retreat.

<Automatic control system of wheel loader 1>
When automating the loading work into the dump truck 300 by the wheel loader 1, in order to ensure the amount of work without bringing the bucket 6 into contact with the vessel 301, and to perform the loading work more quickly, it is necessary to use a work machine for a skilled operator. It is desired to reproduce the operation in step 3 through automatic control. FIG. 4 is a block diagram showing the configuration of the automatic control system of the wheel loader 1.

The automation controller 100 is configured to be able to send and receive signals to and from the vehicle body controller 50 described with reference to FIG. The automation controller 100 is also configured to be able to send and receive signals to and from the external world information acquisition section 110. The external world information acquisition unit 110 includes 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.

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

The sensing 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) that emits a laser beam to obtain information about an object. Perceptual device 111 may be a visual sensor including a camera. The perception device 111 may be a Radar (Radio Detection and Ranging) that acquires information about an object by emitting radio waves. The sensing device 111 may be an infrared sensor.

The position information acquisition device 112 acquires information on the current position of the wheel loader 1. The position information acquisition device 112 uses, for example, 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 uses, for example, GNSS (Global Navigation Satellite Systems) and has a GNSS receiver. The satellite positioning system calculates the position of the wheel loader 1 by calculating the position of the antenna of the GNSS receiver based on the positioning signal that the GNSS receiver receives from the satellite.

The external world information of the wheel loader 1 obtained by the sensing 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.

The vehicle body controller 50 is configured to be able to send and receive signals to and from the vehicle information acquisition section 120, and receives input of information about the wheel loader 1 that the vehicle information acquisition section 120 acquires. The vehicle information acquisition unit 120 is composed of various sensors mounted on the wheel loader 1. The vehicle information acquisition unit 120 includes an articulate 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.

The articulate angle sensor 121 detects an articulate angle, which is the angle formed by the front frame 2a and the rear frame 2b, and generates a signal of the detected articulate angle. The articulate angle sensor 121 outputs an articulate angle signal to the vehicle body controller 50.

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

The boom angle sensor 123 is composed of, for example, a rotary encoder provided on the boom pin 9, which is the attachment portion of the boom 14 to the vehicle body frame 2. The boom angle sensor 123 detects the angle of the boom 14 with respect to the horizontal direction and generates a signal of the detected angle of the boom 14. Boom angle sensor 123 outputs a signal indicating the angle of boom 14 to vehicle controller 50 .

The bucket angle sensor 124 is composed of, for example, a rotary encoder provided on the support pin 18a, which is the rotation axis of the bell crank 18. Bucket angle sensor 124 detects the angle of bucket 6 with respect to boom 14 and generates a signal of the detected angle of bucket 6. Bucket angle sensor 124 outputs a signal indicating the angle of bucket 6 to vehicle controller 50 .

The boom angle sensor 123 and the bucket angle sensor 124 correspond to an example of a "work machine attitude sensor" that detects the attitude of the work machine 3.

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

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 detected values from the vehicle speed sensor 122, boom angle sensor 123, and bucket angle sensor 124 via the vehicle body controller 50.

The actuator 140 is configured to be able to transmit and receive signals to and from the vehicle body controller 50. In response to a command signal from the vehicle body controller 50, the actuator 140 is driven. The actuator 140 includes a brake EPC (electromagnetic proportional control valve) 141 for operating the brake of the traveling device 4, a steering EPC 142 for adjusting the running direction of the wheel loader 1, and a working machine for operating the working machine 3. It includes an EPC 143 and an HMT (Hydraulic Mechanical Transmission) 144.

The electromagnetic

proportional control valves

35 and 36 shown in FIG. 2 constitute a working machine EPC 143. The transmission 23 shown in FIG. 2 is realized as an HMT 144 that utilizes electronic control. The transmission 23 may be an HST (Hydro-Static Transmission). 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 HMT, HST, and electric drive device. .

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

The work machine controller 80 has a steering control section 81 and a work machine control section 82. The steering control unit 81 outputs a command signal for controlling the running direction of the wheel loader 1 to the steering EPC 142. The work machine control unit 82 outputs a command signal for controlling the operation of the work machine 3 to the work machine EPC 143.

The automation controller 100 has a position estimation unit 101, a path planning unit 102, and a path following control unit 103.

The position estimation unit 101 estimates the self-position of the wheel loader 1 based on the position information acquired by the position information acquisition device 112. Further, the position estimating unit 101 recognizes the target position based on the external world information acquired by the sensing device 111. The target position is, for example, the position of the excavated object 310 or the dump truck 300 shown in FIG. 3 . The position estimation unit 101 is capable of acquiring a predetermined reference point of the dump truck 300, for example, the position of the upper end of the side surface of the vessel 301. The sensing device 111 may recognize the target position and input it to the automation controller 100, or the position estimation unit 101 may recognize the target position based on the detection result detected by the sensing device 111.

The path planning unit 102 generates an optimal route for the wheel loader 1 when automatically controlling the wheel loader 1. The optimal route includes a traveling route by the traveling device 4 and an operation route of the working machine 3. For example, the path planning unit 102 determines an optimal route for the wheel loader 1 to move forward with a load toward the dump truck 300 and an optimal route for the wheel loader 1 to move backward and leave the dump truck 300 with an empty load in the loading operation on the dump truck 300. and generate. The path planning unit 102 also generates an optimal route connecting the current self-position of the wheel loader 1 and the target position to which the wheel loader 1 is heading while executing the loading operation onto the dump truck 300.

The traveling route of the traveling device 4 included in the optimal route may be generated based on the actual traveling history based on the operator's operations. Alternatively, the travel route may be a travel route determined by calculation.

The route following control unit 103 controls the accelerator, brake, and steering so that the wheel loader 1 follows the optimal route generated by the path planning unit 102. A command signal for causing the wheel loader 1 to travel along the optimal route is output from the route following control section 103 to the brake control section 71, the accelerator control section 72, and the steering control section 81. The path following control section 103 controls the boom cylinder 16 and the bucket cylinder 19 so that the working machine 3 operates along the optimal path generated by the path planning section 102. A command signal for moving the work machine 3 along the optimal route is output from the route following control unit 103 to the work machine control unit 82.

The interface 130 is configured to be able to send and receive signals to and from the vehicle body controller 50. The interface 130 includes a mode selection operation section 131, an engine emergency stop switch 132, and a mode lamp 133.

The mode selection operation section 131 is operated by an operator. The operator selects the operation mode of the wheel loader 1 by operating the mode selection operation section 131. The operation modes of the wheel loader 1 include a manual mode in which the wheel loader 1 is operated manually and an auto mode in which the wheel loader 1 is automatically controlled. In addition, the operation mode is record & edit mode, which records the actual work based on operator operations and edits the parameters recorded during the work in order to generate the optimal route when automatically controlling the wheel loader 1. including.

If the manual mode is selected, the work is executed by the operator's operations. When the auto mode is selected, the wheel loader 1 is automatically controlled to execute the work. When the operator operates the wheel loader 1 to perform work with the record & edit mode selected, the work is recorded, the feature points in the trajectory of the work equipment 3 during the work are extracted, and each feature is The position and attitude of the work implement 3 at the point are determined. A route that sequentially follows each feature point is generated, and this generated route is used as the operation route of the working machine 3 when automatically controlling the wheel loader 1.

The engine emergency stop switch 132 is operated by the operator. When an event occurs that requires an emergency stop of the engine 21, the operator operates the engine emergency stop switch 132. Signals from the operation of the mode selection operation section 131 and the engine emergency stop switch 132 are input to the vehicle body controller 50.

The mode lamp 133 displays whether the wheel loader 1 is currently in a manual mode operated manually by an operator, an auto mode automatically controlled, or a record & edit mode. A command signal for controlling lighting of the lamp is output from the vehicle body controller 50 to the mode lamp 133.

<Work records (records) of skilled operators>
FIG. 5 is a flowchart showing the flow of processing for recording work machine control when a skilled operator performs a loading operation of the bucket 6 into the vessel 301 of the dump truck 300.

First, as a preliminary preparation, before starting the loading work, the operator selects the operating mode of the wheel loader 1 in step S100. The operator operates the mode selection operation section 131 to select the record & edit mode. The operation of the mode selection operation section 131 may be a button operation or a monitor operation.

In step S101, the shape of the vessel 301 of the dump truck 300, which is a container into which a load is loaded, is recognized. For example, the shape of the dump truck 300 is acquired using LiDAR, which is the sensing device 111. LiDAR irradiates the dump truck 300 with laser light to obtain point group data indicating three-dimensional coordinate values of measurement points on the dump truck 300. The dump truck 300 can be detected from the front, rear, right, and left sides, and the shape of the vessel 301 can be recognized from the point cloud information. The recognized shape of the vessel 301 is input to the automation controller 100.

In step S102, the perception device 111 recognizes the reference point P of the vessel 301 of the dump truck 300. LiDAR, which is the sensing device 111, detects the dump truck 300. The automation controller 100 recognizes the position of the vessel 301 by comparing the point cloud detected by the perception device 111 with a master point cloud indicating the shape of the vessel 301 . The automation controller 100 sets the upper end of the side surface of the vessel 301 of the dump truck 300 recognized by LiDAR, which is the sensing device 111, as a reference point P.

When generating a travel route based on the actual travel history based on operator operations, the reference point P is determined based on the position when loading was performed. In this case, the sensing device 111 detects the loading position of the vessel 301 during the loading operation, and determines the reference point P from the loading position.

After completing the processing in steps S101 and S102, in step S103, the operator on board the wheel loader 1 performs an operation to load the load in the bucket 6 into the vessel 301. As described with reference to FIGS. 3(C) and 3(D), the operator causes the wheel loader 1, on which the work equipment 3 (bucket 6) is loaded, to travel forward toward the vessel 301. The operator operates the work equipment 3 (boom 14, bucket 6) at an appropriate timing, and switches the running direction of the wheel loader 1 from forward to reverse at an appropriate timing. Thereby, the operator loads the load loaded on the working machine 3 (bucket 6) into the bucket 301.

FIG. 6 is a diagram showing the trajectory of the working machine 3 when a skilled operator loads the vessel 301. 6 and subsequent FIGS. 9 to 14, the vessel 301 is schematically shown as seen from the front and rear directions of the dump truck 300, and the wheel loader 1 approaching the vessel 301 from the left or right side of the dump truck 300 is shown schematically. A part of the front side is shown schematically. The wheel loader 1 is running on a flat ground G. The ground G on which the wheel loader 1 runs is horizontal.

The trajectory TR shown in FIG. 6 is such that after the wheel loader 1 starts moving forward (dump approach) toward the dump truck 300 for loading the load in the bucket 6 into the vessel 301, This is the trajectory followed by the cutting edge 6a of the bucket 6 until the wheel loader 1 leaves the dump truck 300 after being discharged.

As shown in FIG. 6, an xy coordinate system is set with the reference point P as the origin. The x-axis is the left-right direction of the dump truck 300 passing through the reference point P. The direction away from the vessel 301 with respect to the reference point P is the +x direction. The y-axis is the vertical direction passing through the reference point P. The upward direction from the reference point P is the +y direction.

The bucket angle θ shown in FIG. 6 is the angle between the ground and the back surface 6b of the bucket 6. The bucket angle θ may be an angle between the back surface 6b of the bucket 6 and a horizontal plane based on the vehicle body.

In step S104, the automation controller 100 recognizes the current position of the cutting edge 6a of the bucket 6. The position information acquisition device 112 acquires the current position of the vehicle body of the wheel loader 1, and the attitude of the work equipment with respect to the vehicle body is acquired by the boom angle sensor 123 and the bucket angle sensor 124, thereby determining the position of the cutting edge 6a of the bucket 6 in the global coordinate system. You can recognize your current location. Based on the current positions of the wheel loader 1 and the working machine 3 and the current position of the dump truck 300 in the global coordinate system, the relative position of the cutting edge 6a of the bucket 6 with respect to the vessel 301 of the dump truck 300 can be calculated.

Alternatively, by using the sensing device 111 to obtain the direction and distance of the reference point P of the vessel 301 of the dump truck 300 with respect to the arrangement position of the sensing device 111, the current relative position of the cutting edge 6a of the bucket 6 with respect to the reference point P can be determined. may be calculated and this relative position may be recognized as the current position.

In step S105, the path planning unit 102 of the automation controller 100 records parameters while the operator performs the loading operation into the vessel 301. The parameters to be recorded include the horizontal and vertical positions of the cutting edge 6a of the bucket 6 with respect to the reference point P, that is, the x and y coordinates. The parameters also include the bucket angle θ. The path planning unit 102 can calculate the bucket angle θ from the detection results of the boom angle sensor 123 and the bucket angle sensor 124 attached to the work machine 3.

While the operator is loading the vessel 301, the current position of the cutting edge 6a of the bucket 6 and the bucket angle θ are recorded. From the current position of the cutting edge 6a of the bucket 6 and the bucket angle θ, the attitude of the working machine 3 while the operator is performing the loading operation into the vessel 301 is recorded.

In step S106, the automation controller 100 determines whether the loading operation is finished. For example, it can be recognized from the detection result of the boom cylinder pressure sensor 125 that all the loads in the bucket 6 have been discharged into the vessel 301 and the bucket 6 has become empty. When it is recognized that the current position of the cutting edge 6a of the bucket 6 has moved away from the dump truck 300 while the inside of the bucket 6 is empty, it can be determined that the loading operation has ended.

If it is determined in step S106 that the loading operation has not been completed (NO in step S106), the process returns to step S104, and while the operator is performing the loading operation into the vessel 301, the cutting edge 6a of the bucket 6 is The recognition of the current position and the recording of the parameters are repeated.

If it is determined in step S106 that the loading operation has been completed (YES in step S106), the record of the skilled operator's work is ended ("end record" in FIG. 5).

A skilled operator performs an operation for loading the load loaded on the working machine 3 (bucket 6) into the vessel 301 from the time it starts in step S103 until it ends in step S106, including recognition of the current position of the cutting edge 6a in step S104 and , and recording the parameters at the current position in step S105 are repeated. By plotting the horizontal and vertical positions of the cutting edge 6a of the bucket 6 with respect to the reference point P, that is, the x and y coordinates, the locus TR of the cutting edge 6a shown in FIG. 6 is obtained. The path planning unit 102 stores the acquired trajectory TR. The path planning unit 102 also stores the reference point P of the vessel 301 acquired in step S102.

<Editing recorded parameters>
FIG. 7 is a flowchart showing the flow of processing for editing the parameters recorded in step S105 shown in FIG. 5 so as to be used in automatic control of the loading operation.

In step S201, the path planning unit 102 extracts feature points constituting the trajectory TR from the trajectory TR of the working machine 3 (the cutting edge 6a of the bucket 6) during the loading operation, shown in FIG. In this embodiment, feature points a, b, c, d, f, and g, which will be described in detail below, are extracted.

FIG. 8 is a graph showing changes in cylinder length during loading work. The horizontal axis in FIG. 8 shows the passage of time, and auxiliary lines are drawn at the times when the cutting edge 6a passes through the feature points a, b, c, d, f, and g. The vertical axis in FIG. 8 indicates the lengths of the boom cylinder 16 and the bucket cylinder 19.

While the wheel loader 1 is traveling forward toward the dump truck 300, the position of the cutting edge 6a of the bucket 6 when the bucket 6 starts moving in the dumping direction for loading the load in the bucket 6 into the vessel 301 is as follows. It is extracted as feature point a. FIG. 9 is a diagram schematically showing the attitude of the wheel loader 1 when starting the dumping operation of the bucket 6. The feature point a is a position where the cutting edge 6a of the bucket 6 passes while the wheel loader 1 is traveling forward toward the dump truck 300. The feature point a is further away from the vessel 301 than the reference point P. The feature point a is located in front of the reference point P of the vessel 301. The feature point a is located higher than the reference point P of the vessel 301.

As shown in FIG. 8 and FIGS. 6 and 9, the wheel loader 1 is traveling forward before the cutting edge 6a reaches the feature point a. The length of the boom cylinder 16 is increasing and therefore the boom 14 is rising. The length of the bucket cylinder 19 is constant, so the attitude of the bucket 6 is constant. The bucket 6 is in a tilted state with an object to be excavated loaded therein. The bucket 6 is in a position that allows the load inside the bucket 6 to be stably transported.

The cutting edge 6a of the bucket 6 when the wheel loader 1 moves forward and approaches the vessel 301 and the cutting edge 6a of the bucket 6 moves to the farthest side (to the left in FIGS. 9 to 14). The position is extracted as feature point b. FIG. 10 is a diagram schematically showing the attitude of the wheel loader 1 when the cutting edge 6a reaches the innermost position. The feature point b is a position where the cutting edge 6a of the bucket 6 passes after passing the feature point a and exceeding the reference point P. The feature point b is above the vessel 301.

As shown in FIG. 8 and FIGS. 9 and 10, the wheel loader 1 continues to travel forward until the cutting edge 6a passes the feature point a and reaches the feature point b. Boom cylinder 16 continues to increase in length and thus boom 14 continues to rise. The movement of the bucket 6 in the dumping direction is started when the cutting edge 6a reaches the feature point a, and the bucket 6 continues to move in the dumping direction until it reaches the feature point b. The length of bucket cylinder 19 continues to decrease. In the movement of the cutting edge 6a from feature point a to feature point b, the dumping operation of the bucket 6 has a greater influence on the position of the cutting edge 6a than the lifting of the boom 14. Therefore, feature point b is lower in height than feature point a. The value of the y-coordinate of feature point b is smaller than the value of the y-coordinate of feature point a.

As shown in FIG. 8, after the cutting edge 6a reaches the feature point a, the rising speed of the boom 14 becomes smaller. The raising operation of the boom 14 is gradual. Before the cutting edge 6a reaches the feature point b, the rising speed of the boom 14 increases again.

The position of the cutting edge 6a of the bucket 6 when the bucket 6 stops moving in the dumping direction above the vessel 301 is extracted as the feature point c. FIG. 11 is a diagram schematically showing the attitude of the wheel loader 1 when the dumping operation of the bucket 6 is stopped. The feature point c is a position where the cutting edge 6a of the bucket 6 passes after passing the feature point b. The movement of the bucket 6 in the dumping direction continues from when the cutting edge 6a of the bucket 6 passes the feature point a until it reaches the feature point c. When the cutting edge 6a of the bucket 6 is at the feature point c, the bucket 6 is in a full dump state. When the cutting edge 6a of the bucket 6 is at the feature point c, the length of the bucket cylinder 19 is the minimum. The feature point c is located closer to the reference point P than the feature point b.

As shown in FIG. 8 and FIGS. 10 and 11, the wheel loader 1 continues to travel forward until the cutting edge 6a passes the feature point b and reaches the feature point c. Boom cylinder 16 continues to increase in length and thus boom 14 continues to rise. Bucket cylinder 19 continues to decrease in length, so bucket 6 continues to move in the dumping direction. When the cutting edge 6a reaches the feature point c, the bucket 6 assumes the full dumping position, and the dumping operation of the bucket 6 stops. When the cutting edge 6a reaches the feature point c, the length of the bucket cylinder 19 is at its minimum. In the movement of the cutting edge 6a from feature point b to feature point c, the dumping operation of the bucket 6 has a greater influence on the position of the cutting edge 6a than the lifting of the boom 14. Therefore, the feature point c is lower in height than the feature point b. The value of the y-coordinate of the feature point c is smaller than the value of the y-coordinate of the feature point b.

During the dumping operation of the bucket 6, the boom 14 continues to rise. While the bucket 6 is being unloaded, the boom 14 continues to rise. While loading the dump truck 300, the boom 14 continues to rise. During the dumping operation of the bucket 6, the wheel loader 1 moves toward the vessel 301 of the dump truck 300, and therefore continues to travel forward.

The position of the cutting edge 6a of the bucket 6 when the operation of raising the boom 14 is stopped above the vessel 301 is extracted as a feature point d. FIG. 12 is a diagram schematically showing the attitude of the wheel loader 1 when the raising operation of the boom 14 is stopped. The feature point d is a position where the cutting edge 6a of the bucket 6 passes after passing the feature point c. In order to avoid interference with the vessel 301 of the working machine 3, the wheel loader 1, which is traveling forward toward the dump truck 300, is raising the boom 14. The raising operation of the boom 14 is continued from when the wheel loader 1 starts the dump approach until the cutting edge 6a of the bucket 6 reaches the feature point d. When the cutting edge 6a of the bucket 6 is at the feature point d, the height position of the boom 14 is at its highest. When the cutting edge 6a of the bucket 6 is at the feature point d, the length of the boom cylinder 16 is maximum. The feature point d is located closer to the reference point P than the feature point c.

As shown in FIG. 8 and FIGS. 11 and 12, the wheel loader 1 is traveling forward at the time when the cutting edge 6a passes the feature point c, and the wheel loader 1 is moving forward at the time when the cutting edge 6a passes the feature point d. I am driving backwards. While the cutting edge 6a is moving between the feature point c and the feature point d, the running direction of the wheel loader 1 is switched from forward to reverse. Boom cylinder 16 continues to increase in length and thus boom 14 continues to rise. The length of the bucket cylinder 19 is constant, so the attitude of the bucket 6 with respect to the vehicle body is constant. The feature point c is the position where the movement of the bucket 6 in the dumping direction is stopped, and the bucket 6 maintains the full dumping posture while the cutting edge 6a moves from the feature point c to the feature point d.

When the boom 14 stops rising, the load in the bucket 6 has already been loaded into the vessel 301, and the bucket 6 is in an empty state. Since the weight of the load in the bucket 6 is small, the influence of inertia when the boom 14 is stopped is small. Therefore, vibration of the vehicle body is less likely to occur when the operation of raising the boom 14 is stopped at the feature point d.

When switching the running direction of the wheel loader 1 from forward to reverse, the center of gravity shifts in the forward direction. When decreasing the lift of boom 14, the center of gravity of the load in bucket 6 moves. By smoothly moving the load in the bucket 6 to the vessel 301, the time required for loading work can be shortened, and the cycle time of the loading work can be shortened.

The position of the cutting edge 6a of the bucket 6 when the bucket 6 starts moving in the tilt direction above the vessel 301 is extracted as a feature point f. FIG. 13 is a diagram schematically showing the attitude of the wheel loader 1 when starting the tilting operation of the bucket 6. The feature point f is a position through which the cutting edge 6a of the bucket 6 passes after passing the feature point d. The bucket 6 maintains the full dump state from when the cutting edge 6a of the bucket 6 passes through the feature point c until it reaches the feature point f. The feature point f is set closer to the reference point P than the feature point d. From when the cutting edge 6a of the bucket 6 passes the feature point d until it reaches the feature point f, the length of the boom cylinder 16 is constant, and the boom 14 is maintained at the uppermost position.

As shown in FIG. 8 and FIGS. 12 and 13, the wheel loader 1 continues to travel backwards until the cutting edge 6a reaches the feature point f after passing the feature point d. The length of the boom cylinder 16 is constant, so the attitude of the boom 14 with respect to the vehicle body is constant. At this time, the height position of the boom 14 is at its highest. When the boom 14 stops rising, the load in the bucket 6 has already been loaded into the vessel 301, and the bucket 6 is in an empty state. The length of the bucket cylinder 19 is constant, so the attitude of the bucket 6 with respect to the vehicle body is constant. While the cutting edge 6a moves from the feature point d to the feature point f, the wheel loader 1 is running backwards while maintaining the full dump state of the bucket 6.

The position of the cutting edge 6a of the bucket 6 when the movement of the bucket 6 in the tilt direction is stopped is extracted as a feature point g. FIG. 14 is a diagram schematically showing the attitude of the wheel loader 1 when the tilting operation of the bucket 6 is stopped. The feature point g is a position through which the cutting edge 6a of the bucket 6 passes after passing the feature point f. The movement of the bucket 6 in the tilt direction continues from when the cutting edge 6a of the bucket 6 passes through the feature point f until it reaches the feature point g. The feature point g is above the reference point P. The boom 14 is maintained at the highest position from when the cutting edge 6a of the bucket 6 passes the feature point d until it reaches the feature point g.

As shown in FIG. 8 and FIGS. 13 and 14, the wheel loader 1 continues to travel backwards until the cutting edge 6a reaches the feature point g after passing the feature point f. The length of the boom cylinder 16 is constant, so the attitude of the boom 14 with respect to the vehicle body is constant. The movement of the bucket 6 in the tilt direction is started when the cutting edge 6a reaches the feature point f, and the bucket 6 continues to move in the tilt direction until it reaches the feature point g. The length of bucket cylinder 19 continues to increase. When the cutting edge 6a reaches the feature point g, the movement of the bucket 6 in the tilt direction is stopped. The feature point f is the position at which the bucket 6 starts tilting. The feature point g is the position where the tilting operation of the bucket 6 is stopped. While the cutting edge 6a is moving from the feature point f to the feature point g, the wheel loader 1 is running backward while tilting the bucket 6. After loading the dump truck 300, the wheel loader 1 tilts the bucket 6 while moving backward to leave the dump truck 300.

While the bucket 6 is tilting, the attitude of the boom 14 remains constant. After the load is completely discharged from the bucket 6, the boom 14 is held and the bucket 6 is tilted. During this tilting operation of the bucket 6, the wheel loader 1 continues to travel backwards and is traveling in a direction away from the vessel 301 of the dump truck 300.

As shown in FIG. 8, after the cutting edge 6a passes the feature point g, the wheel loader 1 continues to travel backwards. The length of boom cylinder 16 is decreasing and therefore boom 14 is lowering. The length of the bucket cylinder 19 is constant, so the attitude of the bucket 6 with respect to the vehicle body is constant.

Returning to FIG. 7, in step S202, the path planning unit 102 determines whether the work machine 3 is connected to the reference point P based on the recorded parameters at each of the extracted feature points a, b, c, d, f, and g. determine the position and posture of the The path planning unit 102 determines the horizontal and vertical positions of the cutting edge 6a of the bucket 6 with respect to the reference point P, that is, the x and y coordinates, and the bucket angle when the cutting edge 6a of the bucket 6 follows the trajectory TR. θ is memorized. The path planning unit 102 stores the posture of the working machine 3 when the cutting edge 6a of the bucket 6 is at each point on the trajectory TR.

The position of the working machine 3 at each feature point a, b, c, d, f, g is determined by giving the x and y coordinates of the cutting edge 6a of the bucket 6. From the x and y coordinates of each feature point a, b, c, d, f, g and the bucket angle θ at each feature point a, b, c, d, f, g, the cutting edge 6a of the bucket 6 is The posture of the working machine 3 at the feature points a, b, c, d, f, and g is determined.

The feature point a is located at the position where the height position of the cutting edge 6a becomes the highest (the y coordinate becomes the maximum value) during the loading operation. The feature point c is located at the position where the height position of the cutting edge 6a is the lowest (the y coordinate is the minimum value) while the load in the bucket 6 is being unloaded. The y-coordinate of feature point a takes a positive value. The y-coordinate of feature point c takes a negative value. The y coordinates of feature points d, f, and g take positive values.

The x-coordinate of feature point a takes a positive value. The x coordinates of feature points b, c, d, and f take negative values. The feature point b is located at the position where the x-coordinate has the minimum value while the load in the bucket 6 is being unloaded. The x-coordinate of feature point g is zero. The feature point g is located directly above the reference point P.

Then, the process ends ("edit end" in FIG. 7).
<Editing parameters corresponding to changing the reference point (Edit 2)>
In order to automate the loading work into containers of various shapes, it is necessary to set parameters that define the relative position of the wheel loader 1 and the attitude of the work equipment 3 according to the shape of the container. A function that allows easy parameter setting is required. FIG. 15 is a flowchart showing the flow of the second process of editing parameters according to the reference point P of the container.

In step S211, the wheel loader 1 recognizes the shape of the actual container into which the load in the bucket 6 is to be loaded under automatic control. As in step S101, for example, the shape of the dump truck 300 on which the load is actually loaded is acquired using LiDAR, which is the sensing device 111. LiDAR irradiates the dump truck 300 with laser light to obtain point cloud data indicating three-dimensional coordinate values of measurement points on the dump truck 300. The dump truck 300 can be detected from the front, rear, right, and left sides, and the shape of the vessel 301 can be recognized from the point cloud information. The recognized shape of the vessel 301 is input to the automation controller 100.

In step S212, the wheel loader 1 recognizes the reference point P' of the actual container into which the load in the bucket 6 is to be loaded under automatic control. LiDAR, which is the sensing device 111, detects the dump truck 300 that actually loads the cargo. The automation controller 100 recognizes the position of the vessel 301 by comparing the point cloud detected by the perception device 111 with a master point cloud indicating the shape of the vessel 301 . The automation controller 100 sets the upper end of the side surface of the vessel 301 of the dump truck 300 recognized by LiDAR, which is the sensing device 111, as a reference point P'.

In step S213, the path planning unit 102 determines the feature points a', b', c', d', f' with respect to the reference point P' of the actual container into which the wheel loader 1 loads the load in the bucket 6 under automatic control. , g' are determined.

FIG. 16 is a schematic diagram showing characteristic points a', b', c', d', f', and g' according to the vessels 301 of dump trucks 300 of different vehicle grades. Through the process of step S212, a reference point P' is set at the upper end of the side surface of the vessel 301. The dump truck 300 equipped with the vessel 301 shown in FIG. 16 has a smaller vehicle size than the dump truck 300 shown in FIG. 6 which has been loaded in advance by a skilled operator. The vessel 301 shown in FIG. 16 has a height (height above ground) H, which is the distance from the ground G to the vessel 301, which is smaller than that of the vessel 301 shown in FIG.

When the container into which the load is loaded in the bucket 6 is changed, the changed container is detected and it is determined whether or not to change the position of the reference point. Even if the dump truck 300 that actually loads the load by automatic control is a different vehicle from the dump truck 300 that was loaded by a skilled operator, if the vehicle size is the same and the shape of the vessel 301 is the same, The position of the reference point remains unchanged. When the shape of the vessel 301 is different, the reference point is changed, and the feature points are changed in accordance with the changed reference point.

FIG. 17 is a schematic diagram showing the reference point P' when the loading position of the dump truck 300 is changed. A dump truck 300 shown in FIG. 17 has a vessel 301 with different heights from the front to the rear. When a skilled operator performs a loading operation, a load is loaded onto the front part of the vessel 301, and a reference point P at the upper end of the side surface of the vessel 301 at that time is set. When the load is actually loaded by automatic control, the load is loaded into the rear of the vessel 301. At this time, the height position of the reference point P' at the upper end of the side surface of the vessel 301 is different from the reference point P. The reference point P' is located at a lower position than the reference point P.

When the loading position in the container is changed, it is determined whether or not to change the position of the reference point. Even if the position in the vessel 301 where the load is actually loaded by automatic control is different from the position where the load is loaded by a skilled operator, for example, if the upper end of the side surface of the vessel 301 of the dump truck 300 is horizontal and the reference point is If the height positions of the points are the same, the position of the reference point is not changed. When the upper end of the side surface of the vessel 301 is inclined with respect to the horizontal and the height positions of the reference points differ, the feature points are changed according to the reference points at different height positions.

Since each feature point is extracted from the trajectory TR of the cutting edge 6a of the bucket 6, changing the feature point can be said to change the trajectory of the cutting edge 6a.

In response to the change of reference point P to reference point P', feature points a, b, c, d, f, and g are translated in parallel and changed in accordance with the changed reference point P'. The positions of new feature points a', b', c', d', f', and g' are determined.

The x and y coordinates of the feature point a' in the xy coordinate system with the reference point P' as the origin are made the same as the x and y coordinates of the feature point a in the xy coordinate system with the reference point P as the origin. The x and y coordinates of feature points b', c', d', f', and g' in the xy coordinate system with the reference point P' as the origin are the features in the xy coordinate system with the reference point P as the origin, respectively. The x and y coordinates of points b, c, d, f, and g are made the same.

In step S214, the path planning unit 102 determines the position and orientation of the work implement 3 with respect to the reference point P' at each changed feature point a', b', c', d', f', g'. do. The path planning unit 102 stores the bucket angle θ when the cutting edge 6a of the bucket 6 follows the trajectory TR. The path planning unit 102 stores the posture of the working machine 3 when the cutting edge 6a of the bucket 6 is at each point on the trajectory TR. The position of the work implement 3 at each feature point a', b', c', d', f', g' is determined by giving the x and y coordinates of the cutting edge 6a of the bucket 6. The x and y coordinates of each feature point a', b', c', d', f', g' and the stored bucket angle θ at each feature point a, b, c, d, f, g. From this, the attitude of the working machine 3 when the cutting edge 6a of the bucket 6 is located at each feature point a', b', c', d', f', g' is determined.

In step S215, the path planning unit 102 defines the posture of the work equipment 3 at each feature point a', b', c', d', f', g' by the lengths of the boom cylinder 16 and the bucket cylinder 19. do. The lengths of the boom cylinder 16 and the bucket cylinder 19 are uniquely determined from the x and y coordinates of the feature point and the bucket angle θ. The path planning unit 102 calculates the length of the boom cylinder 16 and the length of the bucket cylinder 19 when the cutting edge 6a of the bucket 6 is at each feature point a', b', c', d', f', g'. decide. The path planning unit 102 generates a path in which the cutting edge 6a of the bucket 6 sequentially follows the feature point a', the feature point b', the feature point c', the feature point d', the feature point f', and the feature point g', This is set as the operation route of the working machine 3 included in the optimal route. Then, the process ends ("Edit 2 end" in FIG. 15).

<Automatic control of loading work (play)>
FIG. 18 is a flowchart showing the flow of processing for loading the cargo loaded in the bucket 6 into the vessel 301 under automatic control. The process of automatically controlling the wheel loader 1 according to the changed trajectory when the reference point of the container is changed and the trajectory of the working machine and the feature points on the trajectory are changed in accordance with the change of the reference point will be explained below. .

In step S301, the automation controller 100 recognizes the current positions of the wheel loader 1 and the work machine 3. By acquiring the current position of the vehicle body of the wheel loader 1 with the position information acquisition device 112 and acquiring the attitude of the work implement with respect to the vehicle body with the boom angle sensor 123 and the bucket angle sensor 124, the wheel loader 1 and the work implement in the global coordinate system are 3's current position can be recognized. Based on the current positions of the wheel loader 1 and the working machine 3 and the current position of the dump truck 300 in the global coordinate system, the relative position of the cutting edge 6a of the bucket 6 with respect to the vessel 301 of the dump truck 300 can be calculated.

Alternatively, by using the sensing device 111 to obtain the direction and distance of the reference point P of the vessel 301 of the dump truck 300 with respect to the arrangement position of the sensing device 111, the current relative position of the cutting edge 6a of the bucket 6 with respect to the reference point P can be determined. may be calculated.

Based on the current position of the working machine 3, it is recognized where the cutting edge 6a of the bucket 6 is with respect to each feature point a', b', c', d', f', g'. For example, the cutting edge 6a has not yet reached the feature point a', the cutting edge 6a has passed the feature point a' and is between the feature points a' and b', or the cutting edge 6a has reached the feature point b'. It is recognized as passing through and being between feature point b' and feature point c'. Furthermore, the feature point to which the cutting edge 6a is directed next is recognized as the target position. For example, if the cutting edge 6a has not yet reached the feature point a', the target position is the feature point a', and if the cutting edge 6a is between the feature points a' and b', the target position is the feature point. It is recognized as point b', etc.

In step S302, the automation controller 100 recognizes the length of the boom cylinder 16 and the length of the bucket cylinder 19 at the current position. A boom angle sensor 123 detects the angle of the boom 14 . A bucket angle sensor 124 detects the angle of the bucket 6. The attitude of the working machine 3 is determined from the angle of the boom 14 and the angle of the bucket 6. Based on the attitude of the working machine 3, the length of the boom cylinder 16 and the length of the bucket cylinder 19 at the current position are recognized.

Instead of or in addition to the boom angle sensor 123 and the bucket angle sensor 124, an angle sensor that detects the angle of the bell crank 18 and an angle sensor that detects the angle of the link 15 may be provided. The boom cylinder 16 and the bucket cylinder 19 may be provided with stroke sensors that detect cylinder stroke lengths.

In step S303, the automation controller 100 determines the length of the boom cylinder 16 and the length of the bucket cylinder 19 at the current position recognized in step S302, and the length of the boom cylinder 16 and the length of the bucket cylinder 19 at the target position where the cutting edge 6a will go next. (hereinafter referred to as target cylinder length). The automation controller 100 calculates how far the cylinder should be moved until the cutting edge 6a reaches the next target position.

In step S304, the automation controller 100 refers to the current vehicle speed and determines a target cylinder stroke speed that will result in the target cylinder length when the cutting edge 6a reaches the next target position. The automation controller 100 controls the boom cylinder 16 and the bucket cylinder 19 so that when the cutting edge 6a reaches the next target position, the working machine 3 assumes a posture corresponding to the target position. The current vehicle speed is acquired by vehicle speed sensor 122. The time required to reach the next target position can be calculated from the current position of the cutting edge 6a and the current vehicle speed. The target cylinder stroke speed can be determined by dividing the difference in cylinder length calculated in step S303 by the time required to reach the next target position.

The cylinder stroke amount during which the wheel loader 1 travels a unit distance may be determined. Whether the wheel loader 1 has traveled a unit distance may be determined from the vehicle speed, or may be detected by the sensing device 111.

In step S305, the automation controller 100 outputs a command current corresponding to the target cylinder stroke speed to the vehicle body controller 50. The automation controller 100 outputs a command to the work machine control unit 82 of the work machine controller 80 to extend and contract the boom cylinder 16 and the bucket cylinder 19 at a target cylinder stroke speed. A command is output from the work equipment control unit 82 to the work equipment EPC 143 to extend and retract the boom cylinder 16 and the bucket cylinder 19 at a target cylinder stroke speed.

In step S306, the working machine EPC 143 that has received the command signal adjusts the opening degree, so that appropriate hydraulic oil is supplied to the boom cylinder 16 and the bucket cylinder 19. This causes the boom cylinder 16 and bucket cylinder 19 to operate.

In step S307, the automation controller 100 recognizes the current lengths of the boom cylinder 16 and bucket cylinder 19 similarly to step S302. The automation controller 100 determines whether the current lengths of the boom cylinder 16 and bucket cylinder 19 have reached the target cylinder length.

If it is determined in step S307 that the target cylinder length has been reached (YES in step S307), the process proceeds to step S308, and the automation controller 100 determines whether there is a next target position.

If it is determined in step S307 that the target cylinder length has not been reached (NO in step S307), and if it is determined in step S308 that there is a next target position (YES in step S308) , the process returns to step S301, and the process of expanding and contracting the boom cylinder 16 and the bucket cylinder 19 based on the current position of the working machine 3 is repeated. The cylinder speed is sequentially changed according to the current position of the cutting edge 6a of the bucket 6. If the current position of the cutting edge 6a deviates from the position based on the cylinder speed set in the previous process, the cylinder speed is adjusted.

In the judgment in step S308, if it is judged that there is no next target position (NO in step S308), the loading work is ended ("end of play" in FIG. 18). In this embodiment, this corresponds to the fact that the next target position is not set after the cutting edge 6a passes the feature point g'.

By moving the cutting edge 6a of the bucket 6 so as to pass the feature point a', the feature point b', the feature point c', the feature point d', the feature point f', and the feature point g' in order, the bucket 6, The cargo in the bucket 6 can be loaded into the vessel 301 without bringing the vehicle body and running wheels 4a into contact with the vessel 301. By applying automatic control for moving the bucket 6 to the wheel loader 1 in this manner, it is possible to realize the operation of the working machine 3 equivalent to the operation by a skilled operator.

<Action and effect>
Although some descriptions overlap with the above description, the characteristic configuration and effects of this embodiment are summarized as follows.

As shown in FIGS. 5 and 6, the automation controller 100 controls the cutting edge 6a of the bucket 6 when the wheel loader 1 is operated to load the load loaded on the working machine 3 into the vessel 301 of the dump truck 300. The locus TR of the vessel 301 and the reference point P of the vessel 301 are stored. As shown in FIGS. 15 to 17, when the position of the reference point P is changed to the reference point P', the automation controller 100 adjusts the trajectory TR of the cutting edge 6a according to the changed reference point P'. change.

When a skilled operator loads the wheel loader 1, the trajectory TR of the work equipment 3 and the reference point P of the vessel 301 are recorded, and when the reference point is changed, the reference point P' after the change is recorded. Accordingly, the trajectory of the work machine 3 when automatically controlling the work machine is set. This makes it possible to respond even when loading containers with different shapes or when detailed conditions on the container side change. Since loading can be performed regardless of the shape of the container, it is possible to automate the loading work into containers of various shapes.

As shown in FIGS. 7 to 14, the automation controller 100 controls the characteristic points a, b, Store c, d, f, g. As shown in FIGS. 15 to 17, the automation controller 100 changes the feature points a, b, c, d, f, g to the feature points a', b' according to the changed reference point P'. , c', d', f', g'. Determine the feature points a', b', c', d', f', g' according to the changed reference point P', and determine the feature points a', b', c', d' , f', g' when automatically controlling the work equipment 3, the trajectory of the work equipment 3 to be automatically controlled can be appropriately set, and operations by skilled operators can be easily controlled by automatic control. Can be reproduced.

As shown in FIGS. 5 to 14, the automation controller 100 stores the posture of the working machine 3 at the feature points a, b, c, d, f, and g. By automatically controlling the work machine 3 according to the positions of the feature points a, b, c, d, f, g and the posture of the work machine 3 at the feature points a, b, c, d, f, g, Operator operations can be more faithfully reproduced.

As shown in FIGS. 15 and 16, when the loading vessel 301 is changed, the automation controller 100 detects the changed vessel 301 and determines whether or not to change the position of the reference point P. When the shape of the vessel 301 is changed, the reference point is changed, and the locus TR of the cutting edge 6a is changed in accordance with the changed reference point P'. For example, the height of the boom 14 can be adjusted so that the y-coordinate of the feature point relative to the reference point is kept constant. If the height position of the reference point P' is lower than the reference point P, the boom 14 can be lowered to change the locus TR of the cutting edge 6a. Thereby, it is possible to perform loading work into containers of different shapes by automatic control.

As shown in FIGS. 15 and 17, when the loading position in the vessel 301 is changed, the automation controller 100 determines whether or not to change the position of the reference point P. When the height position of the loading position is changed, the reference point is changed, and the locus TR of the cutting edge 6a is changed in accordance with the changed reference point P'. Thereby, even if the situation on the container side changes, the loading operation into the container can be carried out under automatic control.

As shown in FIGS. 8 and 9, feature point a is the position of the cutting edge 6a when the wheel loader 1 starts moving the bucket 6 in the dumping direction while moving forward toward the vessel 301. By automatically controlling the wheel loader 1 so that the cutting edge 6a passes through the feature point a, the dumping operation of the bucket 6 can be started before the cutting edge 6a has reached the vessel 301. The forward travel of the wheel loader 1 toward the dump truck 300 and the dumping operation of the bucket 6 are performed simultaneously, and by overlapping a plurality of operations in time, the cycle time of the loading operation can be shortened.

As shown in FIGS. 8 and 11, feature point c is the position of the cutting edge 6a when the bucket 6 stops moving in the dumping direction above the vessel 301. By automatically controlling the wheel loader 1 so that the cutting edge 6a passes through the feature point c, the load in the bucket 6 can be reliably loaded into the vessel 301.

As shown in FIGS. 8 and 12, the feature point d is the position of the cutting edge 6a when the operation of raising the boom 14 is stopped above the vessel 301. By automatically controlling the wheel loader 1 so that the cutting edge 6a passes through the feature point d, loading work can be performed without stopping the operation of the work equipment 3, and the shaking of the vehicle due to inertia when the boom 14 stops is reduced. can be suppressed.

As shown in FIGS. 8 and 13, the feature point f is the position of the cutting edge 6a when the bucket 6 starts moving in the tilt direction above the vessel 301. By automatically controlling the wheel loader 1 so that the cutting edge 6a passes through the feature point f, contact between the cutting edge 6a and the back surface 6b of the bucket 6 and the vessel 301 can be avoided.

As shown in FIGS. 8 and 14, the feature point g is the position of the cutting edge 6a when the bucket 6 stops moving in the tilt direction. By automatically controlling the wheel loader 1 so that the cutting edge 6a passes through the feature point g, it is possible to reliably prevent the bucket 6 from coming into contact with the vessel 301. To quickly move a bucket 6 to a posture for the next excavation work by tilting the bucket 6 enough to surely avoid a vessel 301 without tilting the bucket 6 more than necessary. Can be done.

The automation controller 100 that constitutes the automatic control system for the wheel loader 1 described in the above embodiment does not necessarily have to be installed in the wheel loader 1. A controller external to the wheel loader 1 may construct a system that constitutes the automation controller 100. The vehicle body controller 50 mounted on the wheel loader 1 performs a process of transmitting the information acquired by the external world information acquisition section 110, the vehicle information acquisition section 120, etc. to an external controller, and the external controller that receives the signal transmits the information. The positions of the feature points a, b, c, d, f, and g constituting the locus TR of the cutting edge 6a of the bucket 6 with respect to the reference point P may be extracted.

The external controller may be placed at the work site of the wheel loader 1, or may be placed at 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 a worker, such as a notebook computer, a tablet computer, or a smartphone.

In the embodiment, the vessel 301 of the dump truck 300 is used as an example of the container, and the operation of loading the load loaded on the working machine 3 (bucket 6) into the vessel 301 has been described. The container for loading the load loaded onto the work machine 3 is not limited to the vessel 301 of the dump truck 300, but may be, for example, a hopper.

In the embodiment, an example has been described in which the wheel loader 1 is a manned vehicle that includes a cab 5 and an operator rides in the cab 5. The wheel loader 1 may be an unmanned vehicle. The wheel loader 1 does not need to include a cab 5 for an operator to board and operate. The wheel loader 1 does not need to be equipped with a control function by an operator on board. The wheel loader 1 may be a working machine exclusively for remote control. The wheel loader 1 may be controlled by radio signals from a remote control device.

<Additional notes>
The above description includes the features noted below.

(Additional note 1)
A system including a working machine,
The working machine body,
a work machine attached to the work machine main body and having a bucket;
a work machine attitude sensor that detects the attitude of the work machine;
an object sensor that detects objects around the work machine main body;
a controller that communicates with the work machine attitude sensor and the object sensor;
The controller stores the trajectory of the work machine and the reference point of the container when the work machine is operated to load the load in the bucket into the container, and stores the position of the reference point. If changed, the system changes the trajectory according to the changed reference point.

(Additional note 2)
storing the positions of feature points constituting the trajectory;
The system according to supplementary note 1, wherein the feature point is changed according to the changed reference point.

(Additional note 3)
The system according to supplementary note 1 or supplementary note 2, which acquires the attitude of the working machine at the feature point.

(Additional note 4)
The system according to any one of Supplementary Notes 1 to 3, wherein when the container into which the load is loaded is changed, the system detects the changed container and determines whether or not to change the position of the reference point. .

(Appendix 5)
The system according to any one of Supplementary notes 1 to 3, which determines whether or not to change the position of the reference point when the position in the container where the load is loaded is changed.

(Appendix 6)
The feature point is any one of Supplementary notes 1 to 5, including the position of the working machine when the working machine starts moving the bucket in the dumping direction while traveling forward toward the container. system described in.

(Appendix 7)
6. The system according to any one of appendices 1 to 6, wherein the characteristic point includes a position of the working machine when the bucket stops moving in the dumping direction above the container.

(Appendix 8)
The work machine has a boom with the bucket attached to the tip,
The system according to any one of appendices 1 to 7, wherein the characteristic point includes a position of the working machine when the operation of raising the boom is stopped above the container.

(Appendix 9)
The system according to any one of appendices 1 to 7, wherein the characteristic point includes a position of the working machine when the bucket starts moving in a tilt direction above the container.

(Appendix 10)
The system according to appendix 9, wherein the feature point includes a position of the working machine when the bucket stops moving in the tilt direction.

The embodiments disclosed herein are illustrative in all respects and should not be considered restrictive. The scope of the present invention is indicated not by the above description but by the claims, and it is intended that equivalent meanings and all changes within the scope of the claims are included.

1 Wheel loader, 2 Body frame, 2a Front frame, 2b Rear frame, 3 Work equipment, 4 Travel device, 4a, 4b Travel wheels, 5 Cab, 6 Bucket, 8 Operating device, 9 Boom pin, 11 Steering cylinder, 13 Work equipment Pump, 14 Boom, 15 Link, 16 Boom cylinder, 17 Bucket pin, 18 Bell crank, 18a Support pin, 18b, 18c Connection pin, 19 Bucket cylinder, 21 Engine, 23 Transmission, 25 Axle, 32 Main valve, 35, 36 Electromagnetic proportional control valve, 41 accelerator pedal, 42 work equipment operating lever, 50 vehicle controller, 51 machine monitor, 60 engine controller, 70 transmission controller, 71 brake control unit, 72 accelerator control unit, 80 work equipment controller, 81 steering control unit , 82 Work equipment control section, 100 Automation controller, 101 Position estimation section, 102 Path planning section, 103 Route following control section, 110 External world information acquisition section, 111 Perception device, 112 Position information acquisition device, 120 Vehicle body information acquisition section, 121 Articulated angle sensor, 122 Vehicle speed sensor, 123 Boom angle sensor, 124 Bucket angle sensor, 125 Boom cylinder pressure sensor, 130 Interface, 131 Mode selection operation section, 132 Engine emergency stop switch, 133 Mode lamp, 140 Actuator, 141 Brake EPC, 142 Steering EPC, 143 Work equipment EPC, 144 HMT.

Claims

A system including a working machine,
The working machine body,
a work machine attached to the work machine main body and having a bucket;
a work machine attitude sensor that detects the attitude of the work machine;
an object sensor that detects objects around the work machine main body;
a controller that communicates with the work machine attitude sensor and the object sensor;
The controller stores the trajectory of the work machine and the reference point of the container when the work machine is operated to load the load in the bucket into the container, and stores the position of the reference point. If changed, the system changes the trajectory according to the changed reference point.
storing the positions of feature points constituting the trajectory;
The system according to claim 1, wherein the feature point is changed according to the changed reference point.
The system according to claim 2, which stores the attitude of the working machine at the feature point.
According to any one of claims 1 to 3, when the container into which the load is loaded is changed, the changed container is detected and it is determined whether or not the position of the reference point is changed. system.
The system according to any one of claims 1 to 3, which determines whether or not to change the position of the reference point when the position in the container where the cargo is loaded is changed.
The feature point includes the position of the working machine when the working machine starts moving the bucket in the dumping direction while traveling forward toward the container. system.
The system according to claim 2 or 3, wherein the characteristic point includes a position of the working machine when the bucket stops moving in the dumping direction above the container.
The work machine has a boom with the bucket attached to the tip,
4. The system of claim 2 or claim 3, wherein the feature point includes a position of the work implement when the boom-raising operation is stopped above the container.
The system according to claim 2 or 3, wherein the characteristic point includes a position of the work machine when starting the movement of the bucket in a tilt direction above the container.
The system according to claim 9, wherein the feature point includes a position of the work machine when the bucket stops moving in the tilt direction.
storing a trajectory of the working machine and a reference point of the container when the working machine is operated to load a load loaded on the working machine into a container;
A controller for a working machine that changes the trajectory in accordance with the changed reference point when the position of the reference point is changed.
storing a trajectory of the work machine and a reference point of the container when the work machine performs an operation to load a load loaded on the work machine into a container;
A method for controlling a working machine, comprising: when the position of the reference point is changed, changing the trajectory according to the changed reference point.