阅读说明：本技术 自动行驶系统 (Automatic driving system ) 是由 西井康人 于 2019-07-11 设计创作，主要内容包括：在包括多个行驶路径的预定行驶路径中,进入所期望的行驶路径并从所期望的行驶路径开始进行作业。路径生成部,其生成包括使作业车辆自动行驶的多个行驶路径在内的预定行驶路径；自动行驶控制部,其能够使作业车辆沿着预定行驶路径自动行驶；信息获取部,其获取作业车辆的位置信息以及方位信息；以及确定部,其在由作业车辆开始自动行驶之前,确定作业车辆能够开始自动行驶的自动行驶候补路径,确定部基于由信息获取部获取的作业车辆的位置信息以及方位信息,而在作业车辆的前方侧以及后方侧设定候补确定用区域(Q2),并将多个行驶路径中的包括在候补确定用区域(Q2)中的行驶路径(P1)确定为自动行驶候补路径(P4)。(In a predetermined travel route including a plurality of travel routes, a desired travel route is entered and a work is performed from the desired travel route. A route generation unit that generates a predetermined travel route including a plurality of travel routes along which the work vehicle automatically travels; an automatic travel control unit that can automatically travel the work vehicle along a predetermined travel path; an information acquisition unit that acquires position information and orientation information of a work vehicle; and a determination unit that determines an automatic travel candidate route on which the work vehicle can start automatic travel before the work vehicle starts automatic travel, the determination unit setting candidate determination areas (Q2) on the front side and the rear side of the work vehicle on the basis of the position information and the direction information of the work vehicle acquired by the information acquisition unit, and determining a travel route (P1) included in the candidate determination area (Q2) among the plurality of travel routes as the automatic travel candidate route (P4).)

1. An automatic travel system is provided with:

a route generation unit that generates a predetermined travel route including a plurality of travel routes along which the work vehicle automatically travels;

an automatic travel control unit that can automatically travel the work vehicle along a predetermined travel path;

an information acquisition unit that acquires position information and orientation information of a work vehicle; and

a determination unit that determines an automatic travel candidate route on which the work vehicle can start automatic travel before the work vehicle starts automatic travel,

the determination unit sets candidate determination areas on the front side and the rear side of the work vehicle based on the position information and the direction information of the work vehicle acquired by the information acquisition unit, and determines a travel route included in the candidate determination area among the plurality of travel routes as an automatic travel candidate route.

2. The automatic traveling system according to claim 1, wherein,

the automatic travel control unit advances the work vehicle to the automatic travel candidate route when the determination unit determines the travel route included in the candidate determination area for the front side as the automatic travel candidate route,

when the determination unit determines the travel route included in the candidate determination area for the rear side as the automatic travel candidate route, the automatic travel control unit causes the work vehicle to retreat and enter the automatic travel candidate route.

3. The automatic traveling system according to claim 1 or 2, wherein,

the automatic travel system includes a display unit that displays a travel route included in the candidate determination area,

the display unit displays a travel route included in the candidate determination area for the front side so as to be distinguishable from a travel route included in the candidate determination area for the rear side.

4. The automatic traveling system according to any one of claims 1 to 3,

the automatic travel system includes an area selection unit capable of selecting whether to set the candidate determination area on the front side of the work vehicle or to set the candidate determination area on the rear side of the work vehicle,

the determination unit sets the candidate determination area on the front side of the work vehicle or on the rear side of the work vehicle, based on the selection state of the previous area selection unit.

Technical Field

The present invention relates to an automatic travel system for automatically traveling a work vehicle along a target travel path.

Background

The automatic travel system described above automatically travels a work vehicle along a predetermined travel route including a plurality of travel routes generated in advance based on positioning information of the work vehicle acquired using a satellite positioning system or the like (for example, see patent document 1).

In the system described in patent document 1, for example, when the work vehicle is located at a position deviated from a predetermined travel route, an accessible travel route is searched for, and the work vehicle is caused to enter the travel route and the automatic travel is restarted. The following route was searched: a search area is set in the traveling direction (forward side) of the work vehicle using the position information and the direction information of the work vehicle, and a travel route located closest to the work vehicle is selected as an accessible travel route from among travel routes existing in the search area.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2018-4589

Disclosure of Invention

In the system described in patent document 1, since the search area is set on the front side of the work vehicle, a travel route into which the work vehicle can travel can be searched for. However, for example, a travel path located closest to the work vehicle may be present on the rear side of the work vehicle. In this case, the vehicle may enter another travel route other than the travel route located closest to the work vehicle. Therefore, only by setting the search area on the front side of the work vehicle, the user or the like cannot enter the desired travel route, and the work cannot be performed from the desired travel route.

In view of the above circumstances, a main object of the present invention is to provide an automatic travel system capable of entering a desired travel route among predetermined travel routes including a plurality of travel routes and performing work from the desired travel route.

A first characteristic structure of the present invention is a structure including: a route generation unit that generates a predetermined travel route including a plurality of travel routes along which the work vehicle automatically travels; an automatic travel control unit that can automatically travel the work vehicle along a predetermined travel path; an information acquisition unit that acquires position information and orientation information of a work vehicle; and a determination unit that determines an automatic travel candidate route on which the work vehicle can start automatic travel before the work vehicle starts automatic travel, the determination unit setting candidate determination areas on a front side and a rear side of the work vehicle based on the position information and the direction information of the work vehicle acquired by the information acquisition unit, and determining a travel route included in the candidate determination area among the plurality of travel routes as the automatic travel candidate route.

According to this configuration, the determination unit sets the candidate determination area not only on the front side of the work vehicle but also on the rear side of the work vehicle based on the position information and the direction information of the work vehicle. The specification unit can specify the travel route included in the candidate specification area for the front side as the automatic travel candidate route, and can specify the travel route included in the candidate specification area for the rear side as the automatic travel candidate route. Thus, when a desired travel route according to the desire and work situation of the user or the like is included in the candidate determination area for the front side, the user can enter the automatic travel candidate route included in the candidate determination area for the front side and start work; when the desired travel route is included in the candidate determination area for the rear side, the vehicle can enter the automatic travel candidate route included in the candidate determination area for the rear side and start the operation. Therefore, the work can be started from the desired travel route by entering the desired travel route in the predetermined travel routes including the plurality of travel routes.

A second characteristic configuration of the present invention is such that, when the determination unit determines the travel route included in the candidate determination area for the front side as the automatic travel candidate route, the automatic travel control unit advances the work vehicle to enter the automatic travel candidate route, and when the determination unit determines the travel route included in the candidate determination area for the rear side as the automatic travel candidate route, the automatic travel control unit retracts the work vehicle to enter the automatic travel candidate route.

According to this configuration, when the travel route included in the candidate determination area for the front side is determined as the automatic travel candidate route, the work vehicle is advanced to enter the automatic travel candidate route, so that the work vehicle can smoothly enter the automatic travel candidate route. When the travel route included in the candidate determination area for the rear side is determined as the automatic travel candidate route, the work vehicle is retracted to enter the automatic travel candidate route, so that the work vehicle can smoothly enter the automatic travel candidate route. In this way, the work vehicle can be switched between forward and backward in accordance with the determination status of the automatic travel candidate route, and can smoothly enter the automatic travel candidate route, so that automatic travel from the automatic travel candidate route can be efficiently and appropriately started.

A third characteristic configuration of the present invention is summarized as including a display unit that displays a travel route included in the candidate specification area, wherein the display unit displays the travel route included in the candidate specification area for the front side so as to be distinguishable from the travel route included in the candidate specification area for the rear side.

According to this configuration, the display unit displays the travel route included in the candidate determination area for the front side and the travel route included in the candidate determination area for the rear side so as to be distinguishable from each other, and therefore, the user or the like can easily recognize whether the determined automatic travel candidate route is included in the candidate determination area for the front side or the candidate determination area for the rear side. Thus, the user or the like can easily determine which of the automatic travel candidate routes included in the candidate specification area for the front side and the automatic travel candidate route included in the candidate specification area for the rear side meets the expectation by comparing the automatic travel candidate routes.

A fourth characteristic configuration of the present invention is that the automatic travel system includes an area selection unit capable of selecting setting of the candidate determination area on the front side of the work vehicle or setting of the candidate determination area on the rear side of the work vehicle, and the determination unit sets the candidate determination area on the front side of the work vehicle or on the rear side of the work vehicle in accordance with a selection state of the area selection unit.

According to this configuration, when setting the candidate determination area, the area selection unit can select whether to set the candidate determination area on the front side of the work vehicle or to set the candidate determination area on the rear side of the work vehicle, in accordance with the desire of the user or the like, the work situation, or the like. Accordingly, since the appropriate automatic travel candidate route according to the desire of the user or the like, the work status, or the like can be specified, the work can be performed from the appropriate automatic travel candidate route, and the convenience of the user or the like and the work efficiency can be improved.

Drawings

Fig. 1 is a diagram showing a schematic configuration of an automatic traveling system.

Fig. 2 is a block diagram showing a schematic configuration of the automatic traveling system.

Fig. 3 is a diagram showing a work area in a state where a target travel path is generated.

Fig. 4 is a schematic diagram showing a state in which the candidate determination area for the front side is set and the automatic travel candidate route is determined.

Fig. 5 is a schematic diagram showing a state in which the candidate determination area for the front side is set and the tractor is oriented transversely to the work path.

Fig. 6 is a schematic diagram showing a state in which the candidate determination area for the rear side is set and the automatic travel candidate route is determined.

Fig. 7 is a flowchart showing an operation when the tractor is automatically driven in the straight mode.

Fig. 8 is a schematic diagram showing a state in which the candidate determination area for the front side is set and the automatic travel candidate route is determined in the second embodiment.

Detailed Description

An embodiment of an automatic travel system according to the present invention will be described with reference to the drawings.

[ first embodiment ]

In this automatic traveling system, as shown in fig. 1, a tractor 1 is applied as a work vehicle, but in addition to the tractor, it is possible to apply: a riding industrial vehicle such as a riding rice transplanter, a combine harvester, a riding mower, a wheel loader, and a snow sweeper, and an unmanned working vehicle such as an unmanned mower.

As shown in fig. 1 and 2, the automatic travel system includes: an automatic traveling unit 2 mounted on a tractor 1; and a mobile communication terminal 3 that is set to be communicable with the automatic traveling unit 2. The portable communication terminal 3 can employ: a tablet personal computer, a smartphone, or the like having a touch-operable display portion 51 (e.g., a liquid crystal panel) or the like.

The tractor 1 includes a traveling machine body 7, and the traveling machine body 7 includes: left and right front wheels 5 functioning as drivable steered wheels, and left and right drivable rear wheels 6. An engine cover 8 is disposed on the front side of the traveling machine body 7, and an electronically controlled diesel engine (hereinafter referred to as "engine") 9 having a common rail system is provided in the engine cover 8. A cab 10 forming a riding cab is provided behind the engine cover 8 of the travel machine body 7.

A rotary cultivator attachment as an example of the working device 12 is connected to the rear part of the traveling machine body 7 via a 3-point link mechanism 11 so as to be able to ascend and descend and to be able to roll, whereby the tractor 1 can be configured to be of a rotary cultivation type. Instead of the rotary tillage device, a working device 12 such as a plowing machine, a sowing device, or a spreading device may be connected to the rear portion of the tractor 1.

As shown in fig. 2, the tractor 1 includes: an electronically controlled speed change device 13 for changing the speed of power from the engine 9, a full hydraulic power steering mechanism 14 for steering the right and left front wheels 5, right and left brakes (not shown) for braking the right and left rear wheels 6, an electronically controlled brake operating mechanism 15 for hydraulically operating the right and left brakes, a working clutch (not shown) for turning on and off the power transmission to the working device 12 such as a rotary tiller, an electronically controlled clutch operating mechanism 16 for hydraulically operating the working clutch, an electronically hydraulically controlled elevation drive mechanism 17 for elevating and driving the working device 12 such as a rotary tiller, an onboard electronic control unit 18 having various control programs related to automatic travel of the tractor 1, a vehicle speed sensor 19 for detecting the vehicle speed of the tractor 1, a steering angle sensor 20 for detecting the steering angle of the front wheels 5, a steering angle sensor 20 for detecting the steering angle of the tractor 5, and a steering control unit for controlling the operation of the tractor, And a positioning unit 21 for measuring the current position and the current orientation of the tractor 1.

The engine 9 may be an electronically controlled gasoline engine equipped with an electronic governor. The transmission 13 may be a hydro-mechanical continuously variable transmission (HMT), a hydrostatic continuously variable transmission (HST), a belt-type continuously variable transmission, or the like. The power steering mechanism 14 may be an electric power steering mechanism 14 including an electric motor.

As shown in fig. 1, the cab 10 is provided with: a steering wheel 38 that can manually steer the left and right front wheels 5 by means of the power steering mechanism 14 (see fig. 2), a driver's seat 39 for a rider, a touch panel type display unit, and various operation elements.

As shown in fig. 2, the in-vehicle electronic control unit 18 has: a shift control unit 181 that controls the operation of the transmission 13, a brake control unit 182 that controls the operation of the right and left brakes, a working equipment control unit 183 that controls the operation of the working equipment 12 such as a rotary cultivator, a steering angle setting unit 184 that sets a target steering angle for the right and left front wheels 5 during automatic travel and outputs the target steering angle to the power steering mechanism 14, a nonvolatile in-vehicle storage unit 185 that stores a target travel path P (see fig. 3, for example) for automatic travel, and the like that have been generated in advance.

As shown in fig. 2, the positioning unit 21 includes: a Satellite Navigation device 22 for measuring the current position and the current orientation of the tractor 1 using a GPS (Global Positioning System) as an example of a Satellite Positioning System (NSS), and an Inertial Measurement Unit (IMU) 23 having a 3-axis gyroscope, a 3-direction acceleration sensor, and the like and measuring the attitude, the orientation, and the like of the tractor 1. The positioning unit 21 acquires the current position (position information) of the tractor 1 and the inertial measurement unit 23 acquires the azimuth information of the tractor 1, and the positioning unit 21 and the inertial measurement unit 23 correspond to an information acquisition unit. Examples of positioning methods using GPS include DGPS (Differential GPS: relative positioning system), RTK-GPS (Real Time Kinematic GPS: interference positioning system), and the like. In the present embodiment, an RTK-GPS suitable for positioning of a mobile body is used. Therefore, as shown in fig. 1 and 2, a positioning base station 4 capable of positioning using RTK is provided at a known position around the field.

As shown in fig. 2, the tractor 1 and the base station 4 each include: positioning antennas 24 and 61 for receiving radio waves transmitted from a positioning satellite 71 (see fig. 1), and communication modules 25 and 62 for enabling wireless communication of various information including positioning information between the tractor 1 and the base station 4. Thus, the satellite navigation device 22 can measure the current position and the current azimuth of the tractor 1 with high accuracy based on the positioning information obtained by the tractor-side positioning antenna 24 receiving the radio wave from the positioning satellite 71 and the positioning information obtained by the base station-side positioning antenna 61 receiving the radio wave from the positioning satellite 71. Further, the positioning unit 21 is provided with the satellite navigation device 22 and the inertial measurement device 23, and can measure the current position, the current azimuth, and the attitude angle (yaw angle, roll angle, pitch angle) of the tractor 1 with high accuracy.

As shown in fig. 1, the positioning antenna 24, the communication module 25, and the inertia measurement device 23 provided in the tractor 1 are housed in the antenna unit 80. The antenna unit 80 is disposed at an upper position on the front surface side of the cab 10.

As shown in fig. 2, the mobile communication terminal 3 includes: a terminal electronic control unit 52 having various control programs for controlling the operations of the display unit 51 and the like, and a communication module 55 capable of performing wireless communication of various information including positioning information with the tractor-side communication module 25. The terminal electronic control unit 52 has: a travel route generating unit 53 that generates a target travel route P (see fig. 3, for example) for the tractor 1 to automatically travel, a nonvolatile terminal storage unit 54 that stores various input information input by the user, the target travel route P generated by the travel route generating unit 53, and the like.

When the travel route generation unit 53 generates the target travel route P, a user such as a driver or a manager inputs vehicle body information such as the type or model of the work vehicle or the work equipment 12 in accordance with input guidance for setting the target travel route displayed on the display unit 51 of the mobile communication terminal 3, and the input vehicle body information is stored in the terminal storage unit 54. The working area S (see fig. 3) to be generated of the target travel path P is defined as a field, and the terminal electronic control unit 52 of the mobile communication terminal 3 acquires field information including the shape and position of the field and stores the field information in the terminal storage unit 54.

The acquisition of field information will be explained. The terminal electronic control unit 52 can acquire position information for specifying the shape, position, and the like of the field from the current position, and the like, of the tractor 1 acquired by the positioning unit 21 by actually driving the tractor 1 by driving by a user or the like. The terminal electronic control unit 52 specifies the shape and position of the field from the acquired position information, and acquires field information including the working area S specified from the specified shape and position of the field. Fig. 3 shows an example in which the rectangular work area S is determined.

When the field information including the shape, position, and the like of the identified field is stored in the terminal storage unit 54, the travel route generation unit 53 generates the target travel route P using the field information and the vehicle body information stored in the terminal storage unit 54.

As shown in fig. 3, the travel route generation unit 53 divides the inside of the work area S into a center area R1 and an outer periphery area R2. The central region R1 is set in the central portion of the working region S, and is a reciprocating working region in which the tractor 1 automatically travels in the reciprocating direction and performs a predetermined work (for example, a work such as tilling). The outer peripheral region R2 is set around the central region R1. The travel path generation unit 53 obtains a turning travel space and the like necessary for turning the tractor 1 at the ridge of the field, for example, from the turning radius included in the vehicle body information, the front-rear width, the left-right width, and the like of the tractor 1. The travel route generation unit 53 divides the work area S into a center area R1 and an outer periphery area R2 so as to secure a space or the like determined on the outer periphery of the center area R1.

As shown in fig. 3, the travel route generation unit 53 generates a target travel route P (corresponding to a planned travel route) using vehicle body information, field information, and the like. For example, the target travel path P has: a plurality of linear work paths P1 (corresponding to travel paths) arranged in parallel at a fixed distance corresponding to the work width and having the same straight travel distance in the center region R1; and a connection path P2 that connects the start end and the end of the adjacent operation path P1. The plurality of work paths P1 are paths through which the tractor 1 performs a predetermined work while traveling straight. The connection path P2 is a U-turn path for switching the traveling direction of the tractor 1 by 180 degrees without performing a predetermined work, and connects the terminal end of the work path P1 to the start end of the next work path P1 adjacent thereto. Incidentally, the target running path P as shown in fig. 3 is only an example, and which kind of target running path is set is appropriately changeable.

The target travel route P generated by the travel route generation unit 53 can be displayed on the display unit 51 and stored in the terminal storage unit 54 as route information associated with vehicle body information, field information, and the like. The travel route information includes: the azimuth angle of the target running path P, and a set engine rotational speed, a target running speed, and the like set according to the running manner of the tractor 1 on the target running path P and the like.

In this way, when the travel route generation unit 53 generates the target travel route P, the terminal electronic control unit 52 transmits the route information from the mobile communication terminal 3 to the tractor 1, and the onboard electronic control unit 18 of the tractor 1 can acquire the route information. The onboard electronic control unit 18 can automatically travel the tractor 1 along the target travel path P while acquiring its own current position (the current position of the tractor 1) by the positioning unit 21 based on the acquired path information. The current position of the tractor 1 acquired by the positioning unit 21 is transmitted from the tractor 1 to the portable communication terminal 3 in real time (for example, in a period of several milliseconds), so that the current position of the tractor 1 is grasped by the portable communication terminal 3.

Regarding the transmission of the route information, the entirety of the route information may be transmitted from the terminal electronic control unit 52 to the in-vehicle electronic control unit 18 at once in a stage before the tractor 1 starts the automatic travel. For example, the route information including the target travel route P may be divided into a plurality of route sections each having a predetermined distance with a small information amount. In this case, in the stage before the tractor 1 starts the automatic travel, only the initial route portion of the route information is transmitted from the terminal electronic control unit 52 to the in-vehicle electronic control unit 18. After the start of the automatic travel, each time the tractor 1 reaches a route acquisition point set according to the amount of information or the like, only the route information of the subsequent route portion corresponding to the point may be transmitted from the terminal electronic control unit 52 to the in-vehicle electronic control unit 18.

When starting the automatic travel of the tractor 1, for example, the user moves the tractor 1 to the start point of the target travel route P and, when various automatic travel start conditions are satisfied, the user operates the display unit 51 using the mobile communication terminal 3 to instruct the start of the automatic travel, and the mobile communication terminal 3 transmits an instruction to start the automatic travel to the tractor 1. Thus, in the tractor 1, the onboard electronic control unit 18 receives an instruction to start automatic travel, and starts the following automatic travel control: the tractor 1 is automatically driven along the target driving route P while acquiring its current position (the current position of the tractor 1) by the positioning means 21. The in-vehicle electronic control unit 18 is configured as an automatic travel control unit that performs automatic travel control such as: the tractor 1 is automatically caused to travel along the target travel path P within the working area S based on the positioning information of the tractor 1 acquired by the positioning unit 21 using the satellite positioning system.

The automatic travel control includes the following controls: automatic shift control for automatically controlling the operation of the transmission 13, automatic brake control for automatically controlling the operation of the brake operating mechanism 15, automatic steering control for automatically steering the left and right front wheels 5, and automatic operation control for automatically controlling the operation of the working device 12 such as a rotary cultivator.

In the automatic shift control, the shift control unit 181 automatically controls the operation of the transmission 13 so that a target traveling speed set according to the traveling manner of the tractor 1 on the target traveling path P or the like can be obtained as the vehicle speed of the tractor 1 based on the path information of the target traveling path P including the target traveling speed, the output of the positioning unit 21, and the output of the vehicle speed sensor 19.

In the automatic braking control, the braking control unit 182 automatically controls the operation of the brake operating mechanism 15 so that the left and right brakes can appropriately brake the left and right rear wheels 6 in the braking region included in the route information of the target travel route P, based on the target travel route P and the output of the positioning unit 21.

In the automatic steering control, the steering angle setting unit 184 obtains and sets a target steering angle of the right and left front wheels 5 based on the route information of the target travel route P and the output of the positioning means 21, and outputs the set target steering angle to the power steering mechanism 14 so that the tractor 1 automatically travels on the target travel route P. The power steering mechanism 14 automatically steers the left and right front wheels 5 based on the target steering angle and the output of the steering angle sensor 20 so that the target steering angle can be obtained as the steering angle of the left and right front wheels 5.

In the automatic control for work, the work implement control unit 183 automatically controls the operations of the clutch operating mechanism 16 and the lift driving mechanism 17 based on the route information of the target travel route P and the output of the positioning means 21 so that the predetermined work (for example, tilling work) by the work implement 12 is started as the tractor 1 reaches a work start point such as the start end of the work route P1 (for example, see fig. 3), and so that the predetermined work by the work implement 12 is stopped as the tractor 1 reaches a work end point such as the end of the work route P1 (for example, see fig. 3).

In this way, in the tractor 1, the automatic traveling unit 2 is configured by the transmission 13, the power steering mechanism 14, the brake operating mechanism 15, the clutch operating mechanism 16, the elevation drive mechanism 17, the in-vehicle electronic control unit 18, the vehicle speed sensor 19, the steering angle sensor 20, the positioning unit 21, the communication module 25, and the like.

In this embodiment, not only can the tractor 1 be automatically driven without the user or the like riding in the cab 10, but also the tractor 1 can be automatically driven with the user or the like riding in the cab 10. Therefore, not only can the tractor 1 be automatically driven along the target travel path P by performing the automatic travel control only by the in-vehicle electronic control unit 18 without mounting the user or the like on the cab 10, but also the tractor 1 can be automatically driven along the target travel path P by performing the automatic travel control by the in-vehicle electronic control unit 18 even when the user or the like is mounted on the cab 10.

When a user or the like is riding on the cab 10, it is possible to switch between an automatic travel state in which the tractor 1 is caused to travel automatically by the in-vehicle electronic control unit 18 and a manual travel state in which the tractor 1 is caused to travel by the driving of the user or the like. Accordingly, the automatic travel state can be switched to the manual travel state during the automatic travel on the target travel path P in the automatic travel state, and conversely, the manual travel state can be switched to the automatic travel state during the travel in the manual travel state. The switching between the manual travel state and the automatic travel state may be provided, for example, in the vicinity of the driver seat 39: a switching operation unit for switching between the automatic travel state and the manual travel state can also be displayed on the display unit 51 of the portable communication terminal 3. Further, when the user operates the steering wheel 38 during the automatic travel control by the in-vehicle electronic control unit 18, the automatic travel state can be switched to the manual travel state.

As shown in fig. 1 and 2, the tractor 1 includes an obstacle detection system 100, and the obstacle detection system 100 is configured to detect an obstacle around the tractor 1 (traveling machine body 7) so as to avoid collision with the obstacle. The obstacle detection system 100 includes: a plurality of laser radar (Lidar) sensors 101 and 102 that can three-dimensionally measure the distance to a measurement target using a laser beam; sonar units 103 and 104 each having a plurality of sonars capable of measuring a distance to a measurement target object using an ultrasonic wave; an obstacle detection unit 110; and a collision avoidance control section 111.

The object to be measured by the laser radar sensors 101 and 102 and the sonar units 103 and 104 is an object, a person, or the like. The laser radar sensors 101 and 102 include a front laser radar sensor 101 whose measurement target is the front side of the tractor 1 and a rear laser radar sensor 102 whose measurement target is the rear side of the tractor 1. Sonar units 103 and 104 include a right sonar unit 103 for measuring the right side of tractor 1 and a left sonar unit 104 for measuring the left side of tractor 1.

The obstacle detecting unit 110 is configured to perform the following obstacle detecting process: based on the measurement information of the laser radar sensors 101 and 102 and the sonar units 103 and 104, a measurement target object such as an object or a person within a predetermined distance is detected as an obstacle. The collision avoidance control unit 111 is configured to perform collision avoidance control as follows: when the obstacle detection unit 110 detects an obstacle, the tractor 1 is decelerated or the tractor 1 stops traveling. The collision avoidance control unit 111 not only decelerates the tractor 1 or stops the travel of the tractor 1 during collision avoidance control, but also activates a notification device 26 such as a notification buzzer or a notification lamp to notify the presence of an obstacle. The collision avoidance control unit 111 can notify the presence of an obstacle by communicating from the tractor 1 to the mobile communication terminal 3 using the communication modules 25 and 55 and causing the display unit 51 to display the presence of an obstacle during collision avoidance control.

The obstacle detection unit 110 repeatedly executes obstacle detection processing based on measurement information of the laser radar sensors 101 and 102 and the sonar units 103 and 104 in real time, thereby appropriately detecting an obstacle such as an object or a person. The collision avoidance control unit 111 performs collision avoidance control for avoiding a collision with an obstacle detected in real time.

The obstacle detection unit 110 and the collision avoidance control unit 111 are provided in the in-vehicle electronic control unit 18. The in-vehicle electronic control unit 18 is communicably connected to an electronic control unit for an engine, the laser radar sensors 101 and 102, the sonar units 103 and 104, and the like included in the common rail system via a CAN (Controller Area Network).

According to this automatic travel system, the in-vehicle electronic control unit 18 can execute the following straight travel mode in the automatic travel control, in addition to automatically traveling the tractor 1 along the target travel path P from the start point to the end point of the target travel path P: the tractor 1 is caused to automatically travel along the working path P1 only on the plurality of working paths P1 among the target travel paths P.

In the straight travel mode, the in-vehicle electronic control unit 18 automatically travels the tractor 1 along the work route P1 from the start end to the end of the work route P1 in each of the plurality of work routes P1, but switches to manual driving when the tractor 1 reaches the end of the work route P1. Therefore, during the turning travel from the end of the work route P1 to the start of the next work route P1, the user or the like manually drives the vehicle. In the target travel route P shown in fig. 3, the travel direction of the tractor 1 is defined as a fixed direction for each of the plurality of work routes P1, but in the straight travel mode, the travel direction in which the tractor 1 is automatically caused to travel is not defined as a fixed direction for each of the plurality of work routes P1, and the tractor 1 may be caused to automatically travel in the direction opposite to the arrow shown in fig. 3.

When the tractor 1 starts to automatically travel in the straight travel mode, the tractor 1 can be automatically traveled from any one of the plurality of work paths P1. As described above, since the travel route generation unit 53 generates the target travel route P including the plurality of work routes P1, it is possible to specify any one of the work routes P1 of the plurality of work routes P1 as the start route P5 (see fig. 4 and 6), and to start the automatic travel from the specified start route P5.

As shown in fig. 2, the automatic travel control device includes a specification unit 91 and a start route specification unit 93, wherein the specification unit 91 specifies an automatic travel candidate route P4 (see fig. 4 and 6) on which the tractor 1 can start automatic travel in the straight travel mode before the tractor 1 starts automatic travel, and the start route specification unit 93 specifies a start route P5 (see fig. 4 and 6) from the automatic travel candidate route P4 specified by the specification unit 91. The specification unit 91 includes a candidate specification area setting unit 92 that sets candidate specification areas Q1, Q2 (see fig. 4, 6) on the front side and the rear side of the tractor 1 based on the acquired current position (position information) and heading information of the tractor 1, and specifies the work route P1 included in the candidate specification areas Q1, Q2 as the automatic travel candidate route P4. Since the current position (position information) of the tractor 1 is acquired by the positioning unit 21 and the azimuth information of the tractor 1 is acquired by the inertial measurement unit 23, the current position (position information) and the azimuth information of the tractor 1 are communicated by the communication modules 25 and 55, and the candidate specification area setting unit 92 grasps the current position (position information) and the azimuth information of the tractor 1.

Next, a case where automatic traveling is started in the straight traveling mode will be described with reference to the flowchart of fig. 7 and based on fig. 4 to 6. Fig. 4 to 6 show a part of the display screen displayed on the display unit 51 of the mobile communication terminal 3, in which the current position of the tractor 1 is displayed superimposed on the plurality of work paths P1.

For example, the tractor 1 is positioned in the vicinity of the work path P1 on which the tractor 1 is intended to start its automatic travel. At this time, the area selection unit 94 (see fig. 2) selects the candidate determination area Q1 (see fig. 4) set on the front side of the tractor 1 or the candidate determination area Q2 (see fig. 6) set on the rear side of the tractor 1 based on the operating state of the tractor 1 (step #1 in fig. 7). The operation status of the tractor 1 is, for example, a switching status of a forward/reverse switching operation unit (reverser) that switches between forward and reverse of the tractor 1.

Next, a case where the forward/reverse switching operation unit is switched to forward will be described.

In this case, the area selection unit 94 selects the state in which the candidate determination area Q1 is set on the front side of the tractor 1, and the candidate determination area setting unit 92 sets the candidate determination area Q1 for the front side of the tractor 1 according to the selected state of the area selection unit 94 (when step #1 in fig. 7 is the front side, the process proceeds to step # 2). As shown in fig. 4, the candidate specification area setting unit 92 sets the right front straight line T2 and the left front straight line T3 as follows: the forward travel straight line T1 extending in the forward direction (forward-side straight direction) of the tractor 1 is obtained by rotating at a rotation angle θ 1 to the left and right, respectively, with the current position of the tractor 1 as the center. The candidate specification area setting unit 92 sets an area between the right front straight line T2 and the left front straight line T3 and within a range from the current position of the tractor 1 to the set distance L as the candidate specification area Q1 for the front side.

In this way, the candidate determination region setting unit 92 sets: the candidate determination region Q1 for the front side of the triangular shape that expands in the straight traveling direction toward the front side of the tractor 1 with reference to the current position of the tractor 1. The candidate determination area Q1 for the front side is not limited to the triangular area described above, and various shapes such as a rectangular shape and an arc shape may be used. The candidate specification area setting unit 92 may set the size of the candidate specification area Q1 for the front side to a fixed size, but the size of the candidate specification area Q1 for the front side may be changed and set according to the current position of the tractor 1 or the like and the situation of the tractor 1.

When the candidate determination area Q1 for the front side is set, the determination unit 91 determines whether or not the direction of the forward direction of the tractor 1 in the forward direction is transverse to the working path P1 (step #3 in fig. 7). As shown in fig. 5, for example, when the angle β formed by the left front straight line T3 (or the right front straight line T2) and the straight line along the working path P1 is a predetermined angle, the direction of the forward direction of the tractor 1 is transverse to the working path P1. In this case, it is difficult to know whether the tractor 1 is approaching the work path P1 on which the automatic travel is to be started or whether the automatic travel of the tractor 1 is to be started from a certain work path P1. Therefore, when the direction of the forward direction of the tractor 1 is transverse to the working path P1, the determination unit 91 does not perform the determination of the automatic travel candidate path P4 (yes in step #3 in fig. 7).

If the direction of the forward direction of the tractor 1 is not transverse to the working path P1, the determination unit 91 determines whether or not the working path P1 is present in the candidate specification region Q1 for the front side, and determines the working path P1 present in the candidate specification region Q1 for the front side as the automatic travel candidate path P4 (if no at step #3 and yes at step #4 in fig. 7, the routine proceeds to step # 5). If one work route P1 is present in the candidate specification area Q1 for the front side, the specification unit 91 specifies the one work route P1 as the automatic travel candidate route P4. As shown in fig. 4, if a plurality of work routes P1 are present in the candidate specification area Q1 for the front side, the specification unit 91 specifies a plurality of work routes P1 (four work routes P1, fourth to seventh from the left in fig. 4) as the automatic travel candidate route P4.

With respect to the automatic travel candidate route P4 determined by the determination unit 91, the terminal electronic control unit 52 can cause the display unit 51 to display the automatic travel candidate route P4 in a state in which: it is possible to identify which of the plurality of work paths P1 is determined as the automatic travel candidate path P4 as the work path P1. Since the display unit 51 can recognize the automatic candidate route P4 by color, for example, the terminal electronic control unit 52 can recognize the automatic candidate route P4 by color different from the other work route P1.

The start route determining unit 93 determines the start route P5 from the automatic travel candidate route P4 determined by the determining unit 91 (step #6 in fig. 7). If there is one automatic travel candidate route P4 determined by the determination unit 91, the start route determination unit 93 determines the automatic travel candidate route P4 as the start route P5. As shown in fig. 4, if there are a plurality of automatic travel candidate routes P4 specified by the specification unit 91, the start route specification unit 93 specifies one start route P5 (shown by a thick line in fig. 4) from among the plurality of automatic travel candidate routes P4 based on the start route specification condition. The starting route determining condition may be set to the automatic candidate route P4 located at the position closest to the current position of the tractor 1, for example. The start route specification condition may be set to, for example, the automatic candidate travel route P4 selected by a selection operation of a user or the like on the display unit 51, or the start route P5 may be specified in response to a request from a user or the like.

As for the start route P5 determined by the start route determining section 93, as indicated by the thick line in fig. 4, the terminal electronic control unit 52 can cause the display section 51 to display the start route P5 in a state in which: it is possible to identify which of the plurality of work paths P1, the work path P1, is determined as the start path P5. Since the display unit 51 can recognize the automatic candidate route by color, for example, the terminal electronic control unit 52 recognizes the automatic candidate route P4 by making the color different from the color of the other work route P1.

Returning to step #1 in fig. 7, a case where the forward/reverse switching operation unit is switched to reverse will be described.

In this case, the area selection unit 94 selects a state in which the candidate determination area Q2 is set on the rear side of the tractor 1, and the candidate determination area setting unit 92 sets the candidate determination area Q2 for the rear side on the rear side of the tractor 1 based on the selected state of the area selection unit 94 (when step #1 in fig. 7 is the rear side, the process proceeds to step # 7). As shown in fig. 6, the candidate determination region setting unit 92 sets the right rear straight line T5 and the left rear straight line T6 as follows: the rearward travel straight line T4 extending in the rearward direction (the straight direction on the rearward side) of the tractor 1 is obtained by rotating the tractor 1 to the left and right by the rotation angle θ 2 around the current position thereof. θ 2 may be the same rotation angle as θ 1 or may be a rotation angle different from θ 1. The candidate determination region setting unit 92 sets a region between the right rear straight line T5 and the left rear straight line T6 and within a range from the current position of the tractor 1 to the set distance L as the candidate determination region Q2 for the rear side.

The candidate specification area Q2 for the rear side is not limited to a triangular area, and may be in various shapes such as a rectangular shape and an arc shape, as in the candidate specification area Q1 for the front side. The candidate determination region setting unit 92 may change the size of the candidate determination region Q2 for the rear side in accordance with the current position of the tractor 1 or the like and the state of the tractor 1.

The determination unit 91 determines whether or not the direction of the backward movement of the tractor 1 is lateral to the working path P1 (step #3 in fig. 7). Although not shown, the determination as to whether or not the direction of the tractor 1 in the backward direction is transverse to the working path P1 is made, when the angle formed by the right-side backward straight line T5 or the left-side backward straight line T6 (see fig. 6) and the straight line along the working path P1 is a predetermined angle, which is opposite to the forward-backward direction in fig. 5, the determination unit 91 determines that the tractor 1 is transverse in the backward direction.

If the direction of the tractor 1 in the backward direction is not transverse to the working path P1, the determination unit 91 determines whether or not the working path P1 is present in the candidate determination region Q2 for the rear side, and determines the working path P1 present in the candidate determination region Q2 for the rear side as the automatic travel candidate path P4 (if no at step #3 and yes at step #4 in fig. 7, the routine proceeds to step # 5). If one work route P1 exists in the candidate determination area Q1 for the rear side, the determination unit 91 determines the one work route P1 as the automatic travel candidate route P4. As shown in fig. 6, if a plurality of work routes P1 are present in the candidate specification area Q2 for the rear side, the specification unit 91 specifies a plurality of work routes P1 (four work routes P1 from the second to the fifth from the left in fig. 6) as the automatic travel candidate routes P4.

With respect to the automatic travel candidate route P4 determined by the determination unit 91, the terminal electronic control unit 52 can cause the display unit 51 to display the automatic travel candidate route P4 in a state in which: it is possible to identify which of the plurality of work paths P1 is determined as the automatic travel candidate path P4 as the work path P1. Since the display unit 51 can recognize the automatic candidate route P4 by color, for example, the terminal electronic control unit 52 can recognize the automatic candidate route P4 by color different from the other work route P1.

Similarly to the case where the candidate determination region Q1 for the front side is set, the start route specification unit 93 specifies the start route P5 from the automatic travel candidate route P4 specified by the specification unit 91 (step #6 in fig. 7). If there is one automatic travel candidate route P4 determined by the determination unit 91, the start route determination unit 93 determines the automatic travel candidate route P4 as the start route P5. When there are a plurality of automatic travel candidate routes P4 specified by the specification unit 91, the start route specification unit 93 specifies one start route P5 (shown by a thick line in fig. 6) from among the plurality of automatic travel candidate routes P4 based on the start route specification condition.

As for the start route P5 determined by the start route determining section 93, as indicated by the thick line in fig. 6, the terminal electronic control unit 52 can cause the display section 51 to display the start route P5 in a state in which: it is possible to identify which of the plurality of work paths P1, the work path P1, is determined as the start path P5. Since the display unit 51 can recognize the automatic candidate route by color, for example, the terminal electronic control unit 52 recognizes the automatic candidate route P4 by making the color different from the color of the other work route P1.

When the start route P5 is displayed on the display unit 51, as shown in fig. 6, the terminal electronic control unit 52 displays the start route P5 (shown by a thick dotted line) included in the candidate specification area Q1 for the front side and the start route P5 (shown by a thick line) included in the candidate specification area Q2 for the rear side so as to be distinguishable from each other. In fig. 6, the automatic travel candidate route P4 is distinguished by a thick solid line and a thick broken line, but the display unit 51 can recognize the route by changing the color thereof, for example.

In this way, in both the case where the candidate determination region Q1 for the front side is set (see fig. 4) and the case where the candidate determination region Q2 for the rear side is set (see fig. 6), the automatic travel candidate route P4 is determined by the determination unit 91, and the start route determination unit 93 determines one start route P5 from the automatic travel candidate route P4.

In fig. 7, when the candidate specification area Q1 for the front side is set, and when the work route P1 does not exist in the candidate specification area Q1 for the front side, or when the candidate specification area Q2 for the rear side is set, and when the work route P1 does not exist in the candidate specification area Q2 for the rear side, steps #1 to #4, and #7 are repeated. For example, when the tractor 1 is moving, the candidate specification area Q1 for the front side or the candidate specification area Q2 for the rear side moves as the tractor 1 moves (moves forward or backward). Therefore, the automatic travel candidate route P4 can be specified by the presence of the work route P1 in the moved candidate specification area Q1 for the front side or the candidate specification area Q2 for the rear side. Incidentally, the automatic travel candidate route P4 may be interrupted by an interruption condition being satisfied when a predetermined time has elapsed since the automatic travel candidate route P4 was determined.

When the start route P5 is determined, the in-vehicle electronic control unit 18 performs automatic travel control so that the tractor 1 automatically travels on the start route P5 so as to approach the start route P5. When the tractor 1 is brought close to the start route P5 and automatically travels on the start route P5, the in-vehicle electronic control unit 18 switches between forward travel and reverse travel depending on whether the forward/reverse switching operation unit is switched to forward or reverse (steps #8 to #10 in fig. 7). Incidentally, since the determination as to whether the forward/reverse switching operation portion is switched to forward or reverse is made by the in-vehicle electronic control unit 18 in step #1, actually, a new determination is not made, and the determination result in step #1 is used to switch to forward travel or reverse travel on the start route P5.

When the forward/reverse switching operation unit is switched to forward, the onboard electronic control unit 18 automatically drives the tractor 1 on the start route P5 in a state where the tractor 1 is driven forward (when step #8 in fig. 7 is on the forward side, the routine proceeds to step # 9).

When the vehicle-mounted electronic control unit 18 automatically drives the tractor 1 on the start route P5, it checks whether or not the automatic driving start condition is satisfied, and when the automatic driving start condition is satisfied, it starts the automatic driving of the tractor 1 along the start route P5 after receiving the instruction to start the automatic driving (when "yes" in step #11 in fig. 7, the routine proceeds to step # 12).

The in-vehicle electronic control unit 18 determines that the automatic travel start condition is satisfied when four conditions of (1), (2), (3), or (4), (5) in the following (1) to (5) are satisfied, for example.

(1) The current position of the tractor 1 is within a prescribed distance in the lateral direction from the start path P5.

(2) The azimuth deviation between the azimuth of the traveling direction of the tractor 1 and the azimuth of the start path P5 is within a predetermined angle.

(3) When the current position of the tractor 1 is in the center region R1 (see fig. 3), the distance from the current position of the tractor 1 to the outer peripheral region R2 (see fig. 3) is equal to or longer than a predetermined distance.

(4) When the current position of the tractor 1 is in the outer peripheral region R2 (see fig. 3), the distance from the current position of the tractor 1 to the central region R1 (see fig. 3) is within a predetermined distance.

(5) The state in which the start paths P5 satisfying the above (1) and (2) are the same continues for a predetermined time (for example, 1 second).

When the forward/reverse switching operation unit is switched to reverse, the onboard electronic control unit 18 automatically drives the tractor 1 on the start route P5 in a state where the tractor 1 is driven in reverse (when step #8 in fig. 7 is on the rear side, the routine proceeds to step # 10).

In this case, the in-vehicle electronic control unit 18 also checks whether or not the automatic travel start condition is satisfied when the tractor 1 is automatically traveled on the start route P5, and automatically travels the tractor 1 along the start route P5 after receiving the instruction to start the automatic travel when the automatic travel start condition is satisfied (if yes at step #11 in fig. 7, the routine proceeds to step # 12). Incidentally, the automatic travel of the tractor 1 along the start path P5 is performed as forward travel, and therefore the tractor 1 is switched from reverse to forward on the start path P5.

In order to perform automatic travel along the start route P5 and the plurality of work routes P1, the in-vehicle electronic control unit 18 needs to acquire route information on the start route P5 and the plurality of work routes P1 in advance, and therefore, the acquisition of the route information will be described below.

At the stage of determining the start path P5, the terminal electronic control unit 52 can transmit the path information about the start path P5 through the communication module 55, and therefore, the in-vehicle electronic control unit 18 can acquire the path information about the start path P5 by receiving the path information through the communication module 25. After the start of the automatic travel, the terminal electronic control unit 52 transmits the path information related to the work path P1 through the communication module 55 every time it arrives at the transmission timing. Thus, the in-vehicle electronic control unit 18 receives the route information from the communication module 25, and acquires the route information on the work route P1. Thus, the in-vehicle electronic control unit 18 performs automatic travel control based on the acquired route information on the start route P5 and the work route P1, and automatically travels the tractor 1 along the start route P5 and the work route P1.

[ second embodiment ]

In the second embodiment, another embodiment is adopted for the configuration in which the automatic candidate travel route P4 is specified by the specifying unit 91 in the first embodiment. Next, a description will be given of a configuration in which the determination unit 91 determines the automatic travel candidate route P4 in the second embodiment, and descriptions of other configurations will be omitted.

In the first embodiment described above, the determination unit 91 determines the work route P1 included in the candidate determination region Q1 for the front side or the candidate determination region Q2 for the rear side as the automatic travel candidate route P4, but in the second embodiment, even if the work route P1 is included in the candidate determination region Q1 for the front side or the candidate determination region Q2 for the rear side, the determination unit 91 does not determine the work route P1 as the automatic travel candidate route P4 if the work route P1 meets the exclusion condition.

The exclusion condition may be set to be satisfied when any of the following conditions (1) to (4) is satisfied. Incidentally, fig. 8 shows a case where the candidate determination region Q1 for the front side is set, and the exclusion conditions defined in the following (1) and (2) are satisfied. In the state where the candidate determination area Q2 for the rear side is set, the difference is present only between the front side and the rear side, and therefore the illustration is omitted.

(1) As shown in fig. 8, the working path P1 in which the off-field region W1 exists between the current position of the tractor 1 and the end of the working path P1 meets the exclusion condition. In fig. 8, the third working path P1 from the left side is included in the candidate determination region Q1 for the front side, but an out-of-field region W1 exists between the end (lower end) of the working path P1 and the current position of the tractor 1.

(2) When the candidate specification area Q1 for the front side is set, if there is a work route P1 having intersections with the right front straight line T2 and the left front straight line T3 in the candidate specification area Q1 for the front side as shown in fig. 8, the work route P1 meets the exclusion condition if there is an obstacle W2 between the current position of the tractor 1 and the intersections between the right front straight line T2 or the left front straight line T3 and the work route P1. In fig. 8, although there is an intersection of the fifth working path P1 from the left and the right front straight line T2, there is an obstacle W2 between the current position of the tractor 1 and the intersection.

When the candidate determination area Q2 for the rear side is set, if there is a work path P1 having intersection points with the right rear straight line T5 (see fig. 6) and the left rear straight line T6 (see fig. 6) in the candidate determination area Q2 for the rear side, if there is an obstacle W2 between the current position of the tractor 1 and the intersection point of the right rear straight line T5 or the left rear straight line T6 and the work path P1, the work path P1 meets the exclusion condition.

(3) When the candidate determination area Q1 for the front side is set, the operation route P1 in which the distance from the current position of the tractor 1 to the intersection with the right front straight line T2 or the left front straight line T3 is greater than the maximum set distance meets the exclusion condition.

When the candidate determination area Q2 for the rear side is set, the operation path P1, in which the distance from the current position of the tractor 1 to the intersection with the right rear straight line T5 or the left rear straight line T6 is greater than the maximum set distance, meets the exclusion condition.

The work path P1, in which the distance from the current position of the tractor 1 to the end on the near side is greater than the maximum set distance, can also meet the exclusion condition.

(4) The work route P1 on which the automatic travel has been performed to complete the work meets the exclusion condition. Incidentally, the terminal electronic control unit 52 grasps which of the plurality of work paths P1, the work path P1, is a work path on which a work is completed, and can display the work path P1 on the display portion 51 in a recognizable state by being full or the like.

The exclusion condition may be appropriately set, and for example, one or a plurality of conditions may be selected from the above-described conditions (1) to (4).

[ other embodiments ]

Other embodiments of the present invention will be explained.

The configurations of the embodiments described below are not limited to the case of being applied individually, and may be applied in combination with the configurations of other embodiments.

(1) The configuration of the work vehicle can be variously changed.

For example, the work vehicle may be configured to: a hybrid type including the engine 9 and an electric motor for traveling may be configured such that: an electric type including an electric motor for running instead of the engine 9.

For example, the work vehicle is configured as a traveling unit: a half crawler belt type including left and right crawler belts is provided instead of the left and right rear wheels 6.

For example, the work vehicle may be configured to: the right and left rear wheels 6 function as steering wheels.

(2) In the above embodiment, the example in which the mobile communication terminal 3 includes the travel route generation unit 53, the specification unit 91, the candidate specification area setting unit 92, the start route specification unit 93, and the area selection unit 94 has been described, and for example, the travel route generation unit 53, the specification unit 91, the candidate specification area setting unit 92, the start route specification unit 93, and the area selection unit 94 may be provided on the work vehicle side of the tractor 1 or an external management device.

(3) In the above embodiment, the case where the automatic travel of the tractor 1 is started from any of the plurality of work paths P1 when the automatic travel of the tractor 1 is started in the straight travel mode is exemplified, but for example, not limited to the straight travel mode, the automatic travel of the tractor 1 may be started not only from the start point of the target travel path P but also from any of the plurality of work paths P1 when the automatic travel of the tractor 1 is started.

At this time, as shown in fig. 3, since a fixed traveling direction is defined for each of the plurality of work paths P1, the work path P1 in which the forward direction of the tractor 1 is the same direction as the traveling direction of the work path P1 can be determined as the automatic travel candidate path P4. That is, when the candidate determination area Q1 for the front side and the candidate determination area Q2 for the rear side are set and the automatic travel candidate path P4 is determined, the determination unit 91 may determine, as the automatic travel candidate path P4, the work path P1 that satisfies a condition that the forward direction of the tractor 1 is the same direction as the travel direction of the work path P1, in addition to the condition that the work path P1 included in the candidate determination area Q1 for the front side and the candidate determination area Q2 for the rear side is satisfied.

(4) In the above embodiment, as shown in fig. 6, the start route P5 (shown by a thick broken line) included in the candidate specification area Q1 for the front side and the start route P5 (shown by a thick line) included in the candidate specification area Q2 for the rear side are displayed on the display unit 51 so as to be distinguishable from each other. Instead of this, the terminal electronic control unit 52 may be configured to distinguishably display the automatic travel candidate route P4 included in the candidate determination region Q1 for the front side and the automatic travel candidate route P4 included in the candidate determination region Q2 for the rear side on the display unit 51. At this time, the automatic candidate travel route P4 and the start route P5 may be displayed so as to be distinguishable from each other.

Industrial applicability of the invention

The present invention can be applied to various automatic travel systems that automatically travel a work vehicle along a target travel path.

Description of the reference numerals

1 … tractor (work vehicle); 18 … vehicle-mounted electronic control unit (automatic travel control unit); 21 … positioning means (information acquisition section); 23 … inertia measuring device (information acquiring unit); 51 … display part; a 53 … travel route generation unit (route generation unit); 91 … determination section; 94 … area selection part; a candidate determination area in front of Q1 …; candidate determination areas behind Q2 …; a P … target travel path (predetermined travel path); p1 … work route (travel route); p4 … automatically drives the candidate route.