Automated driving method and automated driving system for work vehicles

Abstract

This system aims to reduce the burden of positioning work vehicles at the start of the work, thereby improving work efficiency. [Solution] In the automated driving method for work vehicles, a work start position is set within the field where the work vehicle will begin its work by automated driving. The work vehicle is then driven automatically from the designated driving start area within the field to the work start position.

Description

Technical Field

[0001] The present invention relates to an automatic driving method and an automatic driving system for a work vehicle.

Background Art

[0002] Conventionally, work vehicles such as tractors are known to be capable of autonomous driving (driverless driving) along a set route. For example, there is one shown in Patent Document 1. The work vehicle shown in Patent Document 1 includes a control program that determines a work route in each of a work area (the central part of the work site) where work is performed by the work vehicle and an area excluding the work area (the peripheral part). By autonomously driving the work vehicle along the work route according to the control program, it is possible to automate a predetermined work.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in a conventional work vehicle capable of autonomous driving as shown in Patent Document 1, it was necessary for an operator to drive the work vehicle until the start position of the work. For this reason, conventionally, after the operator places the work vehicle at the work start position, it is necessary to return to another accompanying work vehicle, and there is a problem that the work cannot be started immediately after the work vehicle is placed. Also, when the placement of each work vehicle is far apart, the labor required for the operator to move becomes large.

[0005] This invention has been made in view of the aforementioned current problems, and aims to provide an automated driving method and automated driving system for work vehicles that can reduce the burden of the work of positioning the work vehicle at the work start position (work start point) and improve work efficiency. [Means for solving the problem]

[0006] The problems that this invention aims to solve are as described above, and the means for solving these problems will now be explained.

[0007] In other words, an automatic driving method for a work vehicle according to one aspect of the present invention involves setting a work start position within the field where the work vehicle will begin to drive automatically, and causing the work vehicle to automatically drive from the driving start area set within the field to the work start position. Furthermore, an automated driving system for a work vehicle according to another aspect of the present invention includes an operating device for setting a work start position in the field where the work vehicle will begin working automatically, and the system causes the work vehicle to automatically drive from the set driving start area in the field to the work start position. [Effects of the Invention]

[0008] According to the automated driving method and automated driving system for work vehicles of the present invention, it is no longer necessary for an operator to drive the work vehicle to the work start position (work start point), and the efficiency of work performed using the work vehicle can be improved. [Brief explanation of the drawing]

[0009] [Figure 1] Schematic side view of an autonomous work vehicle and a conventional work vehicle. [Figure 2] Control block diagram for an autonomous work vehicle. [Figure 3] A diagram showing the initial screen of the remote control device. [Figure 4] A diagram showing field settings when using autonomous work vehicles. [Figure 5] A diagram showing the boundaries of the field. [Figure 6]A diagram showing the situation when an autonomous work vehicle starts autonomous operation. [Figure 7] A diagram showing the relationship between the starting position of an autonomous work vehicle and the field. [Figure 8] This diagram shows the determination process based on the azimuth angle when an autonomous work vehicle begins autonomous driving to the work start position. [Figure 9] This diagram shows the autonomous driving status of an autonomous work vehicle to the work start position (when the deviation α is below the threshold). [Figure 10] This diagram shows the autonomous driving status of an autonomous work vehicle to the work start position (when the deviation α exceeds the threshold). [Figure 11] A diagram showing the setting status of the autonomous driving start position for an autonomous work vehicle. [Figure 12] This diagram shows the setting of the autonomous driving start position for an autonomous work vehicle, taking into account the azimuth angle and deviation. [Figure 13] The diagram shows the shapes for setting the autonomous driving start position: (A) circular, (B) rectangular, and (C) a shape that narrows towards the work area. [Modes for carrying out the invention]

[0010] The configuration of an autonomous work vehicle, which is a work vehicle according to one embodiment of the present invention, will be described with reference to Figures 1 to 5. As shown in Figure 1, an embodiment will be described in which an autonomous work vehicle (hereinafter sometimes referred to as an unmanned vehicle) 1, which is capable of autonomous driving without a driver, and a manned work vehicle (hereinafter sometimes referred to as a manned vehicle) 100, which is operated by a worker in coordination with the autonomous work vehicle 1, are defined as tractors, and a rotary tilling device is attached as an implement to both the autonomous work vehicle 1 and the manned work vehicle 100. However, the work vehicle is not limited to a tractor, but may be a combine harvester, etc., and the implement is not limited to a rotary tilling device, but may be a ridging machine, a lawnmower, a rake, a seed planter, a fertilizer spreader, etc.

[0011] In this specification, "autonomous driving" means that the tractor's driving configuration is controlled by the control unit (ECU) of the tractor, and the tractor drives along a predetermined route. Performing agricultural work in a single field with both an unmanned and a manned vehicle may be referred to as coordinated agricultural work, follow-up work, or accompanying work. In addition to "performing agricultural work in a single field with both an unmanned and a manned vehicle," coordinated agricultural work may also include "performing agricultural work in different fields, such as adjacent fields, at the same time with both an unmanned and a manned vehicle."

[0012] Figures 1 and 2 illustrate the overall configuration of the tractor that will become the autonomous work vehicle 1. The tractor's body 2 has an engine 4 housed inside a bonnet 3, a dashboard 14 is provided inside a cabin 12 at the rear of the bonnet 3, and a steering handle 5, which serves as the steering control means, is provided on the dashboard 14. The direction of the front wheels 10 is rotated via the steering device by the rotation of the steering handle 5. The steering actuator 40 that operates the steering device is connected to a steering controller 301 which constitutes the control unit 30. The steering direction of the autonomous work vehicle 1 is detected by a steering sensor 20. The steering sensor 20 consists of an angle sensor such as a rotary encoder and is positioned at the rotation base of the front wheels 10. However, the detection configuration of the steering sensor 20 is not limited and only needs to recognize the steering direction, and may also detect the rotation of the steering handle 5 or the amount of power steering operation. The detected value obtained by the steering sensor 20 is input to the steering controller 301 of the control unit 30.

[0013] The control unit 30 includes a steering controller 301, an engine controller 302, a shift control controller 303, a leveling control controller 304, a work control controller 305, a positioning control unit 306, an autonomous driving control controller 307, etc., each of which is equipped with a storage device such as a CPU (Central Processing Unit), a RAM, a ROM, and an interface. The storage device stores programs, data, etc. for operation, and communication is enabled so that information, data, etc. can be transmitted and received by CAN communication. In addition, the autonomous driving control controller 307 includes a memory 309 which is a storage unit where programs, data, etc. are stored.

[0014] A driver's seat 6 is arranged behind the steering wheel 5, and a transmission case 7 is arranged below the driver's seat 6. Rear axle cases 9·9 are connected in series on both the left and right sides of the transmission case 7, and rear wheels 11·11 are supported by the rear axle cases 9·9 via axles. The power from the engine 4 is transmitted through a transmission (main transmission and auxiliary transmission) in the transmission case 7 to drive the rear wheels 11·11. The transmission is configured by, for example, a hydraulic continuously variable transmission, and the swash plate of a variable displacement hydraulic pump can be actuated by a transmission means 44 such as a motor to enable speed change. The transmission means 44 is connected to the shift control controller 303 of the control unit 30. The rotational speed of the rear wheel 11 is detected by a vehicle speed sensor 27 and input to the shift control controller 303 as the traveling speed. However, the method of detecting the vehicle speed and the arrangement position of the vehicle speed sensor 27 are not limited.

[0015] A PTO clutch and a PTO transmission are housed in the transmission case 7. The PTO clutch is engaged and disengaged by a PTO engagement / disengagement means 45. The PTO engagement / disengagement means 45 is connected to the autonomous driving control controller 307 of the control unit 30 via a display means 49, enabling control of the connection and disconnection of power to the PTO shaft. Also, when a seeder, a ridging machine, etc. are mounted as a work implement, a work implement controller 308 is provided so that the work implement can be independently controlled. The work implement controller 308 is connected to the work control controller 305 via an information communication wiring (so-called, ISOBUS).

[0016] A front axle case 8 is supported by a front frame 13 that supports the engine 4. Front wheels 10·10 are supported on both sides of the front axle case 8, and power from the transmission case 7 can be transmitted to the front wheels 10·10. The front wheels 10·10 are steering wheels and can be rotated by rotating the steering handle 5. The front wheels 10·10 can be steered left and right by a steering actuator 40 composed of a power steering cylinder that serves as a driving means for the steering device. The steering actuator 40 is connected to and controlled by a steering controller 301 of the control unit 30.

[0017] An engine controller 302 serving as engine rotation control means is connected to an engine speed sensor 61, a water temperature sensor, a hydraulic pressure sensor, etc., so that the state of the engine 4 can be detected. The engine controller 302 detects the load from the set rotation speed and the actual rotation speed, controls so as not to cause an overload, and transmits the state of the engine 4 to a remote operation device 112 described later so that it can be displayed on a display device 113.

[0018] Also, a level sensor 29 for detecting the liquid level of fuel is arranged in a fuel tank 15 arranged below the steps and is connected to a display means 49. The display means 49 is provided on the dashboard 14 of the autonomous traveling work vehicle 1 and displays the remaining amount of fuel. Then, the remaining amount of fuel is used by the autonomous traveling control controller 307 to calculate the workable time, and information is transmitted to the remote operation device 112 via the communication device 110, and the remaining amount of fuel and the workable time can be displayed on the display device 113 of the remote operation device 112. Note that the display means for displaying a tachometer, a fuel gauge, hydraulic pressure, abnormalities, and the display means for displaying the current position, etc. may have a separate configuration.

[0019] Display means 49 for displaying a tachometer, a fuel gauge, hydraulic pressure, etc. of the engine 4, a monitor indicating abnormalities, set values, etc. is arranged on the dashboard 14. The display means 49 is a touch panel type like the remote operation device 112, and data input, selection, switch operation, button operation, etc. are also possible.

[0020] Furthermore, a work implement 24 is mounted on the rear of the tractor's body 2 via a work implement mounting device 23 so as to be able to be raised and lowered. In this embodiment, a rotary tilling device is used as the work implement 24, and a lifting cylinder 26 is provided on the transmission case 7. By extending and retracting the lifting cylinder 26, the lifting arm constituting the work implement mounting device 23 is rotated, allowing the work implement 24 to be raised and lowered. The lifting cylinder 26 is extended and retracted by the operation of a lifting actuator 25, and the lifting actuator 25 is connected to a horizontal control controller 304 of the control unit 30. In addition, an inclined cylinder is provided on one of the left or right lift links of the work implement mounting device 23, and an inclined actuator 47 that operates the inclined cylinder is connected to the horizontal control controller 304.

[0021] The positioning control unit 306, which serves as the position detection unit, is connected to a mobile GPS antenna 34 and a data receiving antenna 38 to enable the detection of position information. The mobile GPS antenna 34 and the data receiving antenna 38 are mounted on the cabin 12. The positioning control unit 306 is equipped with a position calculation means to calculate latitude and longitude, and the current position can be displayed on the display means 49 and the display device 113 of the remote control device 112. Although highly accurate positioning can be achieved by using satellite positioning systems (GNSS) such as Quasi-Zenith Satellite Systems (Japan) and GLONASS satellites (Russia) in addition to GPS (USA), this embodiment will be described using GPS.

[0022] The autonomous work vehicle 1 is equipped with a gyro sensor 31 to obtain information on changes in the attitude of the vehicle body 2, and an azimuth detection unit 32 to detect the direction of travel, and is connected to the control unit 30. However, since the direction of travel can be calculated from GPS position measurement, the azimuth detection unit 32 can be omitted. The gyro sensor 31 detects the angular velocity of the vehicle body 2's tilt (pitch) in the longitudinal direction, the angular velocity of the vehicle body 2's tilt (roll) in the lateral direction, and the angular velocity of its rotation (yaw). By integral calculation of these three angular velocities, it is possible to determine the tilt angle in the longitudinal and lateral directions, and the rotation angle of the vehicle body 2. Specific examples of the gyro sensor 31 include mechanical gyro sensors, optical gyro sensors, fluid gyro sensors, and vibration gyro sensors. The gyro sensor 31 is connected to the control unit 30 and inputs information related to these three angular velocities to the control unit 30.

[0023] The azimuth detection unit 32 detects the orientation (direction of travel) of the autonomous driving work vehicle 1. Specific examples of the azimuth detection unit 32 include magnetic compass sensors. Information from the azimuth detection unit 32 is input to the autonomous driving control controller 307 via CAN communication.

[0024] Thus, the autonomous driving control controller 307 calculates the attitude and orientation of the autonomous driving work vehicle 1 (direction, tilt of the vehicle body 2 in the front-rear and left-right directions, and turning direction) using the signals acquired from the gyro sensor 31 and the azimuth angle detection unit 32.

[0025] The position information of the autonomous work vehicle 1 is acquired using GPS (Global Positioning System). Various positioning methods using GPS include standalone positioning, relative positioning, DGPS (Differential GPS) positioning, and RTK-GPS (Real-time Kinematic GPS) positioning. Any of these methods can be used, but in this embodiment, the RTK-GPS positioning method, which has high measurement accuracy, is adopted.

[0026] RTK-GPS (Real-time Kinematic GPS) positioning is a method in which a base station whose position is known and a mobile station whose position is to be determined simultaneously perform GPS observations, transmit the data observed by the base station to the mobile station in real time using wireless or other methods, and determine the position of the mobile station in real time based on the position results of the base station.

[0027] In this embodiment, a positioning control unit 306, a mobile GPS antenna 34, and a data receiving antenna 38 are arranged on the autonomous driving work vehicle 1, while a fixed communication device 35, a fixed GPS antenna 36, ​​and a data transmitting antenna 39 are arranged in predetermined positions, serving as a base station. In this embodiment, RTK-GPS (Real-time Kinematic-GPS) positioning is performed by measuring the phase (relative positioning) at both the base station and the mobile station, and the positioning data obtained by the base station's fixed communication device 35 is transmitted from the data transmitting antenna 39 to the data receiving antenna 38.

[0028] The mobile GPS antenna 34 positioned on the autonomous work vehicle 1 receives signals from GPS satellites 37·37···. These signals are transmitted to the positioning control unit 306 for positioning. Simultaneously, the fixed GPS antenna 36, ​​which acts as a reference station, receives signals from GPS satellites 37·37···, performs positioning with the fixed communication device 35, transmits the data to the positioning control unit 306, and analyzes the observed data to determine the position of the mobile station.

[0029] Thus, the autonomous driving control controller 307 is provided as an autonomous driving means for autonomously driving the autonomous work vehicle 1. In other words, various information acquisition units connected to the autonomous driving control controller 307 acquire the driving status of the autonomous work vehicle 1 as various information, and various control units connected to the autonomous driving control controller 307 control the autonomous driving of the autonomous work vehicle 1. Specifically, the positioning control unit 306 receives radio waves transmitted from GPS satellites 37·37··· to obtain position information of the vehicle body 2 at set time intervals, obtains displacement information and direction information of the vehicle body 2 from the gyro sensor 31 and the azimuth detection unit 32, and controls the steering actuator 40, gear shifting means 44, lifting actuator 25, PTO on / off means 45, engine controller 302, etc. so that the vehicle body 2 drives along a preset path (driving path and work path) R, enabling autonomous driving and automatic work.

[0030] Furthermore, the autonomous work vehicle 1 is equipped with obstacle sensors 41 connected to the control unit 30 to prevent it from colliding with obstacles. For example, the obstacle sensors 41 consist of laser sensors, ultrasonic sensors, and cameras, and are placed on the front, sides, and rear of the vehicle body 2 and connected to the control unit 30. The control unit 30 detects whether there are obstacles in front of, to the side of, or behind the vehicle body 2, and controls the vehicle to stop moving when an obstacle approaches within a set distance.

[0031] Furthermore, the autonomous work vehicle 1 is equipped with a camera 42F that takes pictures of the area in front and a camera 42R that takes pictures of the work equipment behind and the field condition after work, and is connected to the control unit 30. In this embodiment, cameras 42F and 42R are positioned on the front and rear of the roof of the cabin 12, but the position is not limited. They may be positioned on the front and rear of the cabin 12, or a single camera 42 may be positioned in the center of the vehicle body 2 and rotated around a vertical axis to photograph the surroundings, or multiple cameras 42 may be positioned at the four corners of the vehicle body 2 to photograph the area around the vehicle body 2. The images taken by cameras 42F and 42R are displayed on the display device 113 of the remote control device 112 provided on the work vehicle 100.

[0032] The remote control device 112 sets the work path Ra and travel path Rb of the autonomous work vehicle 1 (described later), remotely controls the autonomous work vehicle 1, monitors the driving status of the autonomous work vehicle 1 and the operating status of the work equipment, and stores work data. It includes a control device (CPU and memory), a communication device 111, a display device 113, and the like.

[0033] The manned work vehicle 100 is operated by a worker, and is also equipped with a remote control device 112 to control the autonomous work vehicle 1. The basic configuration of the work vehicle 100 is almost the same as that of the autonomous work vehicle 1, so a detailed explanation is omitted. It is also possible to equip the work vehicle 100 (or the remote control device 112) with a GPS control unit.

[0034] The remote control device 112 is detachably attached to the control panel, such as the dashboard, of the mobile work vehicle 100 and the autonomous mobile work vehicle 1. The remote control device 112 can be operated while attached to the dashboard of the mobile work vehicle 100, carried outside the mobile work vehicle 100 for operation, or attached to the dashboard 14 of the autonomous mobile work vehicle 1. The remote control device 112 can be configured as, for example, a notebook computer or a tablet computer. In this embodiment, it is configured as a tablet computer.

[0035] Furthermore, the remote control device 112 and the autonomous work vehicle 1 are configured to communicate with each other wirelessly, and the autonomous work vehicle 1 and the remote control device 112 are each provided with communication devices 110 and 111 for communication. The communication device 111 is integrated into the remote control device 112. The communication means is configured to enable mutual communication, for example, via wireless LAN. The remote control device 112 has a display device 113 on the surface of its housing, which is a touch panel type operation screen that can be operated by touching the screen, and the communication device 111, CPU, storage device 114, battery, etc. are housed inside the housing.

[0036] Next, the procedure for setting the work path Ra and travel path Rb using the remote control device 112 will be described. The display device 113 of the remote control device 112 is a touch panel, and when the power is turned on and the remote control device 112 is started, the initial screen appears. On the initial screen, as shown in Figure 3, the tractor setting button 201, field setting button 202, route generation setting button 203, data transfer button 204, work start button 205, and end button 206 are displayed.

[0037] First, let's explain the tractor settings. When you touch the tractor setting button 201, if you have previously used this remote control device 112 to perform work with a tractor, that is, if a tractor has been set up in the past, the name (model) of that tractor will be displayed. If multiple tractor names are displayed, touch the name of the tractor you want to use this time to select it, and then return to the initial screen. When setting up a new tractor, you need to specify the tractor model. In this case, you enter the model name directly. Alternatively, multiple tractor models are displayed in a list on the display device 113, allowing you to select the desired model.

[0038] Once the tractor model is selected, a screen for setting the mounting position of the mobile GPS antenna 34 will appear. The mounting position of the mobile GPS antenna 34 varies depending on the tractor and may also vary depending on the technician installing it, so the mounting position is set by displaying the tractor's plan view.

[0039] Once the mounting position of the mobile GPS antenna 34 is set, a screen appears for setting the size, shape, and position of the implement to be attached to the tractor. The implement's position can be selected as the front, between the front and rear wheels, at the rear, or offset. After the implement settings are complete, a screen appears for setting the vehicle speed during operation, the engine speed during operation, the vehicle speed during turns, and the engine speed during turns. It is also possible to set different vehicle speeds for the outward and return journeys during operation. After setting the vehicle speed and engine speed, the screen returns to the initial screen.

[0040] Next, we will explain the field settings. When you touch the field setting button 202, if you have previously used this remote control device 112 to operate a tractor, that is, if there are fields that have been set up in the past, the names of those fields will be displayed. After selecting the field name you want to work on from the displayed list of field names, you can then proceed to the route generation settings described later, or return to the initial screen. It is also possible to edit the set fields or set up new fields.

[0041] If no field is registered, a new field will be created. When a new field is selected, as shown in Figure 4, the tractor (autonomous work vehicle 1) is positioned at one of the four corners A within field H, and the "Start Measurement" button is touched. The tractor is then driven along the outer perimeter of field H to register the field shape. Next, the operator identifies the field shape by registering corner positions A, B, C, and D and inflection points from the registered field shape.

[0042] Once field H is identified, the starting position Sr, working direction F, and ending position Gr are set, as shown in Figure 5. If there are obstacles within field H, the tractor is moved to the location of the obstacle, the obstacle setting button (not shown) is touched, and the tractor drives around the obstacle to set it. If the obstacle is located near the perimeter of field H, or if the obstacle is smaller than the minimum turning radius and driving around its perimeter would make the tractor too large, the field may be registered from the displayed field map. After the above work is completed, or after selecting a previously registered field, a confirmation screen will appear with an OK (confirm) button and an "Edit / Add" button. If there are any changes to a previously registered field, touch the "Edit / Add" button.

[0043] Touching the OK button in the aforementioned field settings will initiate the route generation settings. Route generation settings can also be configured by touching the route generation settings button 203 on the initial screen. When in route generation settings mode, a selection screen is displayed for the position of the mobile work vehicle 100 relative to the autonomous work vehicle 1. In other words, the positional relationship between the autonomous work vehicle 1 and the mobile work vehicle 100 is set. Specifically, four options are displayed and can be selected by touching them: (1) Mobile work vehicle 100 is positioned to the left rear of the autonomous work vehicle 1. (2) Mobile work vehicle 100 is positioned to the right rear of the autonomous work vehicle 1. (3) Mobile work vehicle 100 is positioned directly behind the autonomous work vehicle 1. (4) Mobile work vehicle 100 does not travel alongside (autonomous work vehicle 1 performs the work alone).

[0044] Next, set the width of the implement for the mobile work vehicle 100. In other words, enter the width of the implement as a number. Next, set the number of skips. In other words, set how many paths to skip when the autonomous mobile work vehicle 1 reaches the edge of the field (headland) and moves from the first work path R1 to the second work path R2. Specifically, select one of the following: (1) No skipping. (2) Skip one path. (3) Skip two paths. Next, set the overlap. In other words, set the amount of overlap in the work width between work path R1 and the adjacent work path R2. Specifically, select one of the following: (1) No overlap. (2) Overlap. Note that if you select "Overlap," a numerical input screen will appear, and you cannot proceed to the next step until you enter a number.

[0045] Next, the perimeter is set. That is, the area outside the work area HA, where work is performed by the autonomous work vehicle 1 and the mobile work vehicle 100, or by the autonomous work vehicle 1, is set, as shown in Figure 5. In other words, the headland HB, which is a non-working area where the vehicle turns around at the edge of the field, and the side margins HC, which are non-working areas adjacent to the perimeter of the field on both the left and right sides between the headland HBs, are set. Therefore, field H = work area HA + headland HB + headland HB + side margins HC + side margins HC. Normally, the width Wb of the headland HB and the width Wc of the side margins HC are set to be no more than twice the width of the implement attached to the mobile work vehicle 100, so that after the parallel work by the autonomous work vehicle 1 and the mobile work vehicle 100 is completed, the worker can get into the mobile work vehicle 100 and manually operate it to complete the work around the perimeter twice. However, it is also possible for the autonomous work vehicle 1 to work around the perimeter.

[0046] Once you have finished entering the various settings mentioned above, a confirmation screen will appear. Touching "Confirm" will automatically generate the work path Ra and the travel path Rb. The work path Ra is the path generated within the work area HA, and it is the path taken while performing work; it is a straight line. However, it may extend beyond the work area HA if it is not rectangular. The travel path Rb is the path generated in areas other than the work area HA (headland HB and side clearance HC), and it is the path taken while traveling without performing work; it is a combination of straight and curved lines, and is mainly used for turning at headland HB.

[0047] Work path Ra and travel path Rb are generated for autonomous work vehicle 1 and manual work vehicle 100, respectively. If you want to see the route after it has been generated, you can touch the route generation setting button 203 to display a simulation image for confirmation. Note that work path Ra and travel path Rb are generated even if you do not touch the route generation setting button 203. When work path Ra and travel path Rb are automatically generated, the work start position Sw and work end position Gw are set. Work start position Sw and work end position Gw are set to the nearest corresponding positions from the travel start position Sr and travel end position Gr registered in the field settings. Also, once you have set each item in the route generation settings, the route generation settings will be displayed, and below it, "Route setting button," "Transfer data," and "Return to home" will be displayed as selectable options.

[0048] When transferring the aforementioned information, the data transfer button 204 provided on the initial screen can be touched to transfer the information. Since this transfer is performed by the remote control device 112, it is necessary to transfer this configured information to the control device of the autonomous work vehicle 1. This transfer can be done in two ways: (1) using a terminal, or (2) wirelessly. In this embodiment, when using a terminal, the remote control device 112 and the control device of the autonomous work vehicle 1 are directly connected using a USB cable, or the information is temporarily stored in a USB memory and then connected to the USB terminal of the autonomous work vehicle 1 for transfer. When transferring wirelessly, the transfer is performed using a wireless LAN.

[0049] Here, we will explain how to autonomously drive an autonomous work vehicle 1 according to one embodiment of the present invention to a work start position Sw. As shown in Figure 1, the autonomous work vehicle 1 according to one embodiment of the present invention comprises a vehicle body 2 and a work machine 24 attached to the vehicle body 2. Furthermore, as shown in Figures 1 and 2, it is equipped with a mobile GPS antenna 34, which is a position detection unit capable of detecting the position information of the vehicle body 2. In addition, the autonomous work vehicle 1 is equipped with a control unit 30 that can control the movement of the vehicle body 2 and the work performed by the work machine 24 in the field H, which is the driving area. The control unit 30 is equipped with a memory 309, which is a storage unit capable of storing the shape, position, size, etc., of the field H, which is the driving area on which the vehicle body 2 moves. When the control unit 30 is mentioned in the following description, Figure 2 will be referred to.

[0050] The autonomous work vehicle 1 is configured to autonomously travel along the work path Ra and travel path Rb while detecting the current position N of the vehicle body 2 using the mobile GPS antenna 34. The data of the work path Ra and travel path Rb generated by the remote control device 112 is transferred to the control unit 30 and stored in the memory 309. The current position N of the autonomous work vehicle 1 usually coincides with the position of the mobile GPS antenna 34.

[0051] The autonomous work vehicle 1 shown in this embodiment has a roughly rectangular field H as its operating area, as shown in Figure 6, and is configured to autonomously travel within the first area, the work area HA, and the second area, the headland HB and the side margin HC, which constitute the field H. The mobile work vehicle 100 follows (or accompanies) the autonomous work vehicle 1 that autonomously travels within the operating area, the field H, and is driven by an operator.

[0052] The autonomous work vehicle 1 is configured to be able to travel autonomously when its current location N is within the field H, as controlled by the control unit 30. On the other hand, the autonomous work vehicle 1 is configured not to be able to travel autonomously outside of the field H (e.g., on a public road), as controlled by the control unit 30.

[0053] Furthermore, the autonomous driving work vehicle 1 is configured to be able to drive autonomously by the control unit 30 when its current position N is located at the starting position Sr.

[0054] Furthermore, when the autonomous work vehicle 1 is at its current position N located at the starting position Sr on the headland HB, and the operator presses the start work button 205 (see Figure 3) to give the instruction to "start work", the control unit 30 can be configured to autonomously travel from the current position N to the start work position Sw, as shown in Figure 6, and after reaching the start work position Sw, start work with the work machine 24 (see Figures 1 and 2).

[0055] Since the autonomous work vehicle 1 is configured to start autonomous driving at a location away from the work start position Sw, it is possible to reduce the effort required for the operator to move when the distance between the entrance to the field H and the work start position Sw is large, and consequently, the efficiency of work using the autonomous work vehicle 1 can be improved.

[0056] The remote control device 112 generates a work path Ra and a travel path Rb based on the results of the tractor settings, field settings, and route generation settings described above. The remote control device 112 generates a path R that includes the work path Ra and the travel path Rb from the travel start position Sr set in the field settings to the travel end position Gr, and can transmit the information of path R to the autonomous driving work vehicle 1. The autonomous driving work vehicle 1 (control unit 30), having acquired the information of path R, can compare the current position N and azimuth angle of the autonomous driving work vehicle 1 with the travel start position Sr and work direction F, and can start autonomous driving if the difference is within a predetermined deviation.

[0057] Here, as shown in Figure 7, the entrance to field H is located approximately in the center of the width of field H, and the user (operator) selects point Sa, located approximately in the center of the width of field H, as the starting position Sr for travel in the field setting, and selects point Sb as the ending position Gr for travel.

[0058] In this case, the remote control device 112 generates a route R from point Sa to point Sb. Generally, route R is generated from point Sa to point Sb, but if point Sa is near the approximate center of the width of field H, it is also necessary to generate a route from point Sa to the opposite side of point Sb, which complicates route generation. Furthermore, when the mobile work vehicle 100 works in coordination with the autonomous mobile work vehicle 1, it becomes difficult for the operator controlling the mobile work vehicle 100 to predict which route to take next.

[0059] Therefore, in the autonomous driving work vehicle 1 according to one embodiment of the present invention, when a point other than a corner of field H (for example, point Sa) is specified as the starting position Sr during field setting, the system is configured to allow the operator to choose whether or not to "autonomously drive from point Sa to point Sc without performing agricultural work, and then autonomously drive from point Sc towards point Sb with agricultural work." However, as shown in Figure 6, the operator is only prompted to choose whether or not to "autonomously drive from point Sa to point Sc without performing agricultural work, and then autonomously drive from point Sc towards point Sb with agricultural work" if the distance L between point Sa and point Sc is greater than or equal to a predetermined set value β (for example, set value β = 10m). With this configuration, the operator does not have to drive the autonomous driving work vehicle 1 to the work starting position Sw, but can bring the autonomous driving work vehicle 1 into field H near the entrance and have it autonomously drive, thereby shortening the operator's travel distance and improving work efficiency.

[0060] On the other hand, if the distance L is less than a predetermined set value β, the user may be given the option to either "drive from point Sa to point Sc using operator controls, and then perform autonomous driving with agricultural work from point Sc to point Sb." This is because the burden on the user is small when the distance L is short. Note that the timing of the above selection is not limited to the above timing (i.e., when setting up the field), but may also be at a predetermined timing after the completion of field setting, for example, after generating the route R from point Sa to point Sb and presenting route R to the user (for example, after displaying the simulation image).

[0061] If the user selects to "autonomously drive from point Sa to point Sc without performing agricultural work, and then autonomously drive from point Sc to point Sb with agricultural work," the remote control device 112 generates a route R that includes the work route Ra and driving route Rb, as well as the driving route Rc from point Sa to point Sc, as shown in Figure 6.

[0062] On the other hand, if the user selects to "drive from point Sa to point Sc using operator-controlled driving, and then perform autonomous driving involving agricultural work from point Sc to point Sb," the remote control device 112 generates a route R that includes the work route Ra and the driving route Rb, but does not include the driving route Rc.

[0063] In other words, the autonomous driving work vehicle 1, which is a work vehicle according to one embodiment of the present invention, comprises a vehicle body 2, a work machine 24 attached to the vehicle body 2, a mobile GPS antenna 34 which is a position detection unit capable of detecting the position information of the vehicle body 2, a memory 309 which is a storage unit capable of storing a field H which is a driving area on which the vehicle body 2 travels, and a control unit 30 which is capable of controlling the movement of the vehicle body 2 and the work performed by the work machine within the field H. The field H includes a first area, the work area HA, which includes a work path Ra on which work is performed by the work machine 24, and a second area, the headland HB, which is set around the work area HA. ​​When the control unit 30 is instructed to start work by the work machine 24 in the headland HB, it is possible to drive the vehicle body 2 from the current position N of the vehicle body 2 to the work start position Sw, which is the starting point of the work path Ra, and then start work by the work machine 24. This configuration eliminates the need for an operator to move the autonomous work vehicle 1 to the work start position Sw, thereby improving the efficiency of the work performed using the autonomous work vehicle 1.

[0064] Furthermore, when autonomous driving is performed along a route R that includes the driving path Rc, as shown in Figure 7, it is possible to configure the system to start autonomous driving if the difference between the current position N and azimuth angle θa of the autonomous driving work vehicle 1, any point Sd on a virtual starting line s parallel to the work direction F passing through point Sa, and the angle θb (90 degrees in this embodiment) formed by the line segment connecting point Sa and point Sc and the virtual starting line s is within a predetermined deviation. Here, the predetermined deviation means, for example, that the distance L1 between the current position N and point Sd is within a predetermined set value α (for example, predetermined set value α = 1 m), and the difference between the azimuth angle θa and angle θb is within a predetermined set value ε (for example, predetermined set value ε = 15 degrees).

[0065] Next, we will explain how automatic driving starts when point Sc is selected as the starting position Sr in the field setup, or when point Sa is selected as the starting position Sr, but the operator drives from point Sa to point Sc.

[0066] Previously, the orientation of the work vehicle at the work start position Sw did not take into account its impact on the vehicle's driving accuracy (and consequently, its work accuracy). Therefore, depending on the vehicle's orientation at the work start position Sw, the actual trajectory of the work vehicle may deviate from the set driving path Rb, making it difficult to ensure work accuracy with autonomously driven work vehicles.

[0067] An autonomous work vehicle 1 according to one embodiment of the present invention is configured such that, when the control unit 30 generates a route, it takes into consideration that the orientation (azimuth angle) of the autonomous work vehicle 1 affects the driving accuracy (and consequently the work accuracy).

[0068] The autonomous work vehicle 1 is configured such that, when its current position N is located at the starting position Sr on the headland HB and an instruction to start work is given, the control unit 30 can determine whether or not to start autonomous driving, taking into account the azimuth angle of the autonomous work vehicle 1 at its current position N.

[0069] In the autonomous work vehicle 1, the control unit 30 is configured to calculate the angular difference dθ between the azimuth angle θ1 of the autonomous work vehicle 1 with respect to the reference direction X and the azimuth angle θ2 of the autonomous work vehicle 1 from its current position N to the work start position Sw, as shown in Figure 8. When the calculated angular difference dθ is less than a predetermined threshold, autonomous driving from the current position N to the work start position Sw is permitted.

[0070] When the autonomous work vehicle 1 is located within the headland HB and the operator presses the work start button 205 (see Figure 3), the azimuth angle θ1 with respect to the reference bearing X at the current position N is detected by the azimuth angle detection unit 32 (see Figure 2), and the control unit 30 calculates the azimuth angle θ2 from the current position N to the work start position Sw, and calculates the angular difference dθ between the two azimuth angles θ1 and θ2.

[0071] Furthermore, the autonomous work vehicle 1 can be configured such that, when the angle difference dθ is less than a predetermined threshold (for example, less than 10°), the control unit 30 can permit the autonomous work vehicle 1 to autonomously travel from its current position N to the work start position Sw.

[0072] In other words, the autonomous work vehicle 1, which is a work vehicle according to one embodiment of the present invention, is equipped with an azimuth detection unit 32 capable of detecting the azimuth angle of the vehicle body 2, and the control unit 30 will not allow the vehicle body 2 to travel from the current position N to the work start position Sw unless the angular difference dθ between the azimuth angle θ1 of the vehicle body 2 and the azimuth angle θ2 from the current position N to the work start position Sw is within a predetermined threshold. In this way, by configuring the vehicle body 2 to travel autonomously when the angular difference dθ between the azimuth angle θ1 of the vehicle body 2 and the azimuth angle θ2 is within a predetermined threshold, it is possible to suppress the error of the current position N of the vehicle body 2 with respect to the set work start position Sw.

[0073] Furthermore, the autonomous work vehicle 1 can be configured such that, as shown in Figure 9, the control unit 30 identifies a virtual extension line f that extends the first work path R1, which includes the work start position Sw, toward the headland HB, and when the current position N with respect to the virtual extension line f is within a predetermined deviation, the control unit 30 can permit autonomous driving of the autonomous work vehicle 1. The virtual extension line f is oriented in the direction of the work direction F at the work start position Sw and coincides with the direction of the first work path R1. The "deviation" referred to here is the degree of deviation of the current position N with respect to the virtual extension line f, and specifically, it is the distance of the current position N with respect to the virtual extension line f.

[0074] In other words, the autonomous work vehicle 1 is configured such that, when its current position N is located within the headland HB and an instruction to start work is given, the control unit 30 can determine whether or not to start autonomous driving by considering the deviation of the current position N with respect to the virtual extension line f.

[0075] Specifically, as shown in Figure 9, the autonomous work vehicle 1 can be configured such that, when the deviation of the current position N with respect to the virtual extension line f is within a predetermined deviation α (for example, deviation α = within 1 m), the control unit 30 can permit the autonomous work vehicle 1 to autonomously travel from the current position N to the work start position Sw.

[0076] Furthermore, the autonomous work vehicle 1 can be configured so that the control unit 30 controls the movement of the vehicle body 2 in order to reduce the deviation α between the identified virtual extension line f and the current position N.

[0077] In other words, in an autonomous driving work vehicle 1, which is a work vehicle according to one embodiment of the present invention, the work path Ra includes a first work path R1 that includes the work start position Sw, and the control unit 30 identifies a virtual extension line f, which is a virtual path that extends the first work path R1 to the headland HB, and if the current position N is within a predetermined deviation α with respect to the virtual extension line f, the control unit 30 controls the driving of the vehicle body 2 to reduce the deviation, making it possible to drive the vehicle body 2 from the current position N to the work start position Sw. With this configuration, the error between the current position N and the work start position Sw when the vehicle body 2 reaches the work start position Sw can be suppressed.

[0078] Furthermore, as shown in Figure 10, the autonomous work vehicle 1 can be configured such that, when the deviation of the current position N with respect to the virtual extension line f is outside a predetermined deviation α (for example, deviation α > 1m), the control unit 30 may not permit the autonomous work vehicle 1 to continue autonomously.

[0079] If the deviation of the current position N with respect to the virtual extension line f is outside a predetermined deviation α, the autonomous driving work vehicle 1 can be configured to generate an additional travel path Rb from the current position N to the work start position Sw, and to allow autonomous driving along the additionally generated travel path Rb.

[0080] In other words, in an autonomous driving work vehicle 1, which is a work vehicle according to one embodiment of the present invention, the work path Ra includes a first work path R1 that includes a work start position Sw, and the control unit 30 identifies a virtual extension line f, which is a virtual path that extends the first work path R1 to the headland HB, and if the current position N is outside a predetermined deviation from the virtual extension line f, it generates a travel path Rb from the current position N to the work start position Sw, and makes it possible to drive the vehicle body 2 along the travel path Rb. With this configuration, when the current position N of the vehicle body 2 and the work start position Sw are far apart, the autonomous driving work vehicle 1 can be positioned at the work start position Sw without the operator having to drive it to the work start position Sw, thus saving the operator the trouble of positioning the autonomous driving work vehicle 1 at the work start position Sw.

[0081] Furthermore, in order to minimize the deviation α of the current position N relative to the virtual extension line f, it is advantageous for the path from the current position N to the work start position Sw to be longer.

[0082] Here, we will explain how to set the starting position Sr. The autonomous work vehicle 1 can set a starting position Sr within the field H, as shown in Figure 11, using the control unit 30. The autonomous work vehicle 1 is configured so that when its current position N coincides with the starting position Sr, it is permitted to start autonomous driving.

[0083] Since the current position N of the autonomous work vehicle 1 usually coincides with the position of the mobile GPS antenna 34, the control unit 30 can be configured to initiate autonomous driving when the position of the mobile GPS antenna 34 coincides with the driving start position Sr.

[0084] The autonomous work vehicle 1 is configured to display the starting position Sr and the current position N on the display device 113. By operating the autonomous work vehicle 1 while checking the display device 113, the operator can easily position the autonomous work vehicle 1 relative to the starting position Sr by ensuring that the starting position Sr and the current position N coincide.

[0085] The starting position Sr for travel is preferably set on the headland HB, as shown in Figure 11. Furthermore, it is more preferable that the starting position Sr for travel is on the headland HB and as far away as possible from the starting position Sw for work.

[0086] This is because if the starting position Sr is set as far away as possible from the starting position Sw, there will be enough time for the autonomous work vehicle 1 to correct its azimuth and attitude while it autonomously travels from the starting position Sr to the starting position Sw.

[0087] Furthermore, it is more preferable that the starting position Sr for travel is determined by the control unit 30, which identifies a virtual extension line f, and sets the starting position Sr on the virtual extension line f, and as far away as possible from the working area HA of the headland HB.

[0088] This is because, by positioning the autonomous work vehicle 1 on the virtual extension line f, the azimuth angle and attitude of the autonomous work vehicle 1 can be corrected with greater precision while it autonomously travels from the starting position Sr to the work start position Sw.

[0089] Furthermore, as shown in Figure 12, the autonomous work vehicle 1 can be configured so that the control unit 30 sets the starting position Sr by considering the azimuth angle θ1·θ2 and the deviation α of the current position N with respect to the virtual extension line f. This makes it possible to adjust the azimuth angle and attitude of the autonomous work vehicle 1 at the starting position Sw simply by positioning the autonomous work vehicle 1 at the starting position Sr, thereby improving the work accuracy of the autonomous work vehicle 1.

[0090] In the autonomous work vehicle 1, it is preferable to maximize the distance between the starting position Sr and the starting position Sw in order to reliably reduce the deviation α between the identified virtual extension line f and the current position N, and to reliably reduce the angle difference dθ.

[0091] Furthermore, when setting the starting position Sr for travel, it is preferable to set the starting position Sr as far away as possible from the work area HA on the headland HB, taking into consideration the size and shape of the work implement 24, so that the work implement 24 does not extend beyond the headland HB.

[0092] Furthermore, the autonomous work vehicle 1 has its travel path Rb set by the control unit 30 so that it travels along the headland HB between the travel start position Sr and the work start position Sw. This allows the autonomous work vehicle 1 to be positioned at the work start position Sw without disturbing the work area HA.

[0093] As shown in Figures 11 and 13(A), the autonomous work vehicle 1 sets the starting position Sr as a "region" with a predetermined area. If the starting position Sr were set as a "point," high positioning accuracy would be required to match the current position N with the starting position Sr, making it difficult to position the autonomous work vehicle 1 to the starting position Sr.

[0094] Therefore, in the autonomous work vehicle 1, the required precision during positioning is relaxed by setting the starting position Sr as a "region," and the autonomous work vehicle 1 is configured to be easily positioned at the starting position Sr.

[0095] Specifically, in the autonomous work vehicle 1, the starting position Sr can be set as a "circular area," as shown in Figure 13(A). In this case, it is possible to easily set the "area" that is the starting position Sr simply by specifying the center point and radius of the starting position Sr. Furthermore, it is preferable that the radius of the "circular area" in this case be less than or equal to the initial tolerance allowed at the work start position Sw, thereby ensuring positioning accuracy at the work start position Sw.

[0096] The "area" set as the starting position Sr is set as a "circular area" with a predetermined radius centered on a point specified by the operator. When the mobile GPS antenna 34 of the autonomous work vehicle 1 is positioned within this "area," it is determined that the autonomous work vehicle 1 has been positioned at the starting position Sr. With this configuration, the autonomous work vehicle 1 can be easily positioned at the starting position Sr.

[0097] Furthermore, by setting the "area" to be set as the starting position Sr within the headland HB, it is possible to prevent the autonomous work vehicle 1 from autonomously traveling outside the field H.

[0098] Furthermore, the shape of the "region" set as the starting position Sr is not limited to a circle. For example, as shown in Figure 13(B), it may be a polygon (in this case, a rectangle), and as shown in Figure 13(C), it may also be a shape in which the width narrows from left to right as it approaches the starting position Sw. [Explanation of Symbols]

[0099] 1. Autonomous work vehicle 2. Body 24 Work Machines 32. Azimuth detection unit 34. Mobile GPS antenna (position detection unit) 30 Control Unit 309 Memory (storage unit) H Field (driving area) HA work area (first area) HB Pillow (Second Zone) Ra Work Path Rb Route R1 First work route f Virtual extension Sa Travel start position Sw Work start position N Current position

Claims

1. Set a work start position within the field where the work vehicle will begin its work by automatically driving. An automatic driving method for a work vehicle, comprising automatically driving the work vehicle from a driving start area set within the field to the work start position.

2. The automatic driving method for a work vehicle according to claim 1, wherein the driving start area is set near the entrance of the field.

3. Within the field, an inner area is defined where multiple work paths are generated for the work vehicle to perform work by automatic driving, and an outer area is defined outside the inner area for the work vehicle to drive automatically. The automatic driving method for a work vehicle according to claim 1 or 2, wherein the driving start area is set in the outer area.

4. When an instruction is given to move to the work start position, the work vehicle shall begin moving from its current position to the work start position, provided that one or more permission conditions are met. The method for automatically driving a work vehicle according to any one of claims 1 to 3, wherein the permission condition includes that the current position is located within the driving start area.

5. A travel path is generated for the work vehicle to automatically travel from the travel start area to the work start position. The method for automatically driving a work vehicle according to any one of claims 1 to 4, wherein at least a portion of the aforementioned driving path is within the aforementioned driving start area.

6. The aforementioned travel path includes a turning path leading to the work start position and a straight path leading to the turning path. The method for automatically driving a work vehicle according to claim 5, wherein at least a portion of the straight-ahead path is within the driving start area.

7. The method for automatically driving a work vehicle according to claim 6, wherein the straight-line path is generated along the outer perimeter of the field.

8. It is equipped with an operating device that sets the starting position for the work vehicle to begin working automatically within the field. An automated driving system for a work vehicle, which automatically drives the work vehicle from a driving start area set within the field to the work start position.

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