JP7594739B2 - Work vehicles - Google Patents

Description

The present invention relates to a work vehicle that performs agricultural work while autonomously traveling through farm fields.

Conventionally, as shown in, for example, Patent Document 1 below, a work vehicle is known that uses position information obtained from a satellite positioning system to perform agricultural work (hereinafter simply referred to as work) while automatically traveling in a field. Before starting work, this conventional work vehicle is preset with a travel route (hereinafter referred to as a target travel route), which is a target trajectory when automatically traveling, according to the size and shape of the field. During automatic traveling, the vehicle calculates its own vehicle position (current position of the work vehicle) from the position information at predetermined time intervals, and further calculates the deviation of the vehicle position from the target travel route (deviation in direction and distance), and automatically steers the steering wheel based on the calculated deviation. Note that the target travel route is set in a single stroke in order to efficiently work the entire field, and includes a straight route along which the work vehicle works while traveling straight, and a turning route along which the work vehicle turns and moves between the straight routes.

JP 2018-147163 A

Now, immediately after the start of automatic driving, there is usually a deviation between the target driving route and the vehicle's own position, so a work vehicle with the above-mentioned conventional configuration is prone to meandering until it gets on the straight path of the target driving route and the trajectory stabilizes. As a result, there is a problem that the accuracy of work decreases due to meandering when work is started immediately after the start of automatic driving. For example, in ridge making work or sowing work, meandering can make the ridges or sowing rows look bad, and there is also a risk that a curved ridge or sowing row will be run over by the machine when performing subsequent work of cultivating soil or spraying chemicals.

Therefore, the present invention aims to provide a work vehicle that solves these problems and improves straight-line driving accuracy (straight-line driving ability) immediately after the start of automatic driving, thereby improving work accuracy.

In order to achieve the above object, the first invention provides:
A work vehicle that automatically travels in a field along a target travel route,
A control device is provided that acquires position information during automatic driving, calculates the vehicle's position, and automatically steers the vehicle along a set target driving route.
The control device provides a work vehicle characterized in that it is equipped with a route correction unit that calculates the deviation between the work start point of the target driving route and the vehicle position in a direction perpendicular to the line direction at the start of automatic driving, and corrects the target driving route so that the work start point of the target driving route is in the line direction of the vehicle position.

According to the first invention, immediately after the start of automatic driving, the work vehicle travels straight to the work start point, and while continuing to travel straight, it can transition to the straight-line driving path of the target driving path and begin work. In other words, immediately after the start of automatic driving, it is possible to stably transition to a trajectory on the straight-line driving path by simply adjusting the orientation of the work vehicle. This improves straight-line driving ability immediately after the start of automatic driving, and improves work accuracy.

The second invention is the above-mentioned first invention,
The route correction unit corrects the target travel route by increasing or decreasing intervals between a plurality of straight line travel routes included in the target travel route.

According to the second invention, in addition to the effect of the first invention, it is possible to easily correct the target driving route without increasing the operating costs.

The third invention is the above-mentioned first invention,
The path correction unit corrects the target traveling path by a method of translating a plurality of straight traveling paths included in the target traveling path by an amount of deviation in a direction perpendicular to the row direction.

According to the third invention, in addition to the effect of the first invention, it is possible to correct the target driving path so that the work start point of the target driving path is precisely aligned with the direction of the vehicle position.

A fourth aspect of the present invention is the third aspect of the present invention,
The control device includes an unworked area calculation unit that calculates an unworked area within a working area where work is not expected to be performed using information on a working width of a working machine and the target traveling path during a process of correcting the target traveling path by the path correction unit,
The path correction unit is characterized in that when an unworked area is calculated by the unworked area calculation unit as a result of parallel shifting of multiple straight line driving paths included in the target driving path by an amount of deviation in a direction perpendicular to the row direction, the path correction unit adds a new straight line driving path to the target driving path and corrects the target driving path so that the calculated unworked area is eliminated.

According to the fourth aspect of the present invention, in addition to the effects of the third aspect of the present invention,
This makes it possible to prevent areas from being left unworked as a result of correcting the target travel route.

The fifth invention is the fourth invention,
The route correction unit is characterized in that, when a new straight-line travel route is added to the target travel route, the route correction unit changes the travel order of the straight-line travel routes.

According to the fifth invention, in addition to the effect of the fourth invention, by changing the driving order of the straight driving route, it is possible to prevent discrepancies in the driving order and to drive efficiently.

The present invention provides a work vehicle that improves straight-line stability immediately after starting autonomous driving and improves work accuracy.

FIG. 1 is a left side view of a work vehicle according to an embodiment of the present invention. FIG. 2 is a block diagram showing the configuration of the control device of the work vehicle of FIG. FIG. 3 is an explanatory diagram for explaining a target travel route of a work vehicle. FIG. 4 is an explanatory diagram showing the flow of data relating to setting a target travel route for a work vehicle. FIG. 5 is an explanatory diagram for explaining an overview of the unworked area. FIG. 6 is an explanatory diagram showing a procedure for correcting a target driving route using the overlap width increase/decrease method. FIG. 7 is an explanatory diagram showing a procedure for correcting a target driving route by the straight driving route addition method. FIG. 8 is an explanatory diagram showing a procedure for correcting a target driving route by the headland driving route addition method. FIG. 9 is an explanatory diagram showing a procedure for correcting a target driving route according to a modified example. FIG. 10 is a flowchart showing an example of processing by the control device when starting autonomous driving. FIG. 11 is a flowchart showing an example of the target driving route correction process of FIG.

Below, a preferred embodiment of the present invention will be described with reference to the attached drawings. In the following description, unless otherwise specified, the forward movement direction of the work vehicle is referred to as "front," the opposite direction is referred to as "rear," and the right side when facing forward is referred to as "right" and the left side is referred to as "left."

<1. Configuration of the work vehicle>
FIG. 1 is a left side view of a work vehicle according to an embodiment of the present invention.
The work vehicle A has a so-called tractor configuration in which a work machine WM, which is a work means, is attached to the rear of a traveling body a1 equipped with an automatic traveling means. Note that the traveling body a1 and the work machine WM are not necessarily limited to the configuration of a tractor, and may be, for example, a combine harvester or the like.

As shown in FIG. 1, the vehicle body a1 has an engine EN as the driving source, a fuel tank (not shown), and a control device C that controls each mechanism arranged inside the bonnet a11. The power from the engine EN is changed in speed by a transmission (not shown) inside the transmission case a12, and is transmitted to the front wheels a13 and rear wheels a14, respectively, to drive the vehicle.

A cabin a15 in which the operator sits is provided behind the bonnet a11, and a rotating steering handle ST, which is a steering means for the traveling vehicle body a1, is provided on the dashboard inside the cabin a15.

When the steering handle ST is rotated, the front wheel a13, which is a steered wheel, rotates via a steering device (not shown) according to the direction and amount of rotation, thereby changing the traveling direction of the work vehicle A.

A steering angle detection means (not shown) is provided at the base of the rotation of the steering wheel ST, which is capable of detecting the steering angle corresponding to the rotation direction and operation amount of the steering wheel ST. This steering angle detection means is configured, for example, with an angle sensor such as a rotary encoder. The travel direction of the work vehicle A is determined according to this steering angle.

The work vehicle A can be switched between an automatic driving mode in which the steering wheel ST is automatically operated and a manual driving mode in which the steering wheel ST is operated by the worker, by a control device C described below, by receiving a predetermined operation from the worker via an operating member (not shown).

The rotation axis (steering shaft) of the steering handle ST is provided with a steering actuator (steering motor) (not shown) that controls the rotation of the steering handle ST to enable automatic steering. Feedback control using the steering angle of this steering actuator as the control amount makes it possible to control the driving direction of the work vehicle A during automatic driving.

The transmission case a12 also houses a PTO clutch, a PTO transmission, and a braking device (not shown), making it possible to control the transmission of power to the PTO shaft. This allows the work vehicle A to control the drive of the work machine WM.

At the rear of the traveling vehicle body a1, a lift arm a22, a22 protruding rearward from the side of the hydraulic cylinder case a21, a top link a23, a lower link a24, etc. are arranged, and the working machine WM attached to the working machine attachment device WJ can be raised and lowered by the extension and contraction of the hydraulic cylinder a25. As a result, the working machine WM is configured to be able to switch between a working position where work is performed on the field and a non-working position where no work is performed. For example, if the working machine WM is a tiller, the working position refers to a grounded state, and the non-working position refers to a state where the working machine WM is raised from the grounded state and is not grounded. In the illustrated example, the working machine WM is a rotary tiller, but the working machine WM attached to the work vehicle A can be a fertilizer spreader, a pesticide spreader, a seed spreader, a harvester, etc. in addition to the rotary tiller described above.

The positioning device AN is provided approximately in the center of the traveling vehicle body a1 in the longitudinal direction, and is a device that measures the position of the traveling vehicle body A. The positioning device AN is equipped with a GNSS (Global Navigation Satellite System) that receives radio waves from navigation satellites AS orbiting in the sky using a positioning antenna (not shown) to determine position and time, and is also equipped with an inertial measurement unit that measures the attitude and direction of the work vehicle A using a three-axis gyroscope and a three-directional acceleration sensor.

2. Configuration of the control device
FIG. 2 is a block diagram showing the configuration of a control system including the control device C of the work vehicle A.
The control device C is an information processing device configured by combining multiple ECUs (Electronic Control Units). Each of the multiple ECUs is configured with a CPU that performs arithmetic processing and a memory that can read and write information required for the arithmetic processing. The configuration shown as functional blocks in FIG. 2 is realized by the CPU operating in accordance with various control programs stored in the memory.

As shown in FIG. 2, the control device C includes an output processing unit c1, a communication processing unit c2, an input processing unit c3, a driving control unit c4, an information storage unit c5, and a route management unit c6, which are configured to be able to send and receive information to and from each other via a communication bus BA.

The output processing unit c1 is a device that functions as an input/output interface, and is connected to a traveling system device group MA1 that controls the traveling functions of the work vehicle A, such as traveling, stopping, and changing the traveling direction, a working system device group MA2 that controls the operations of the work machine WM, such as raising/lowering, driving, and stopping, and a notification unit MA3 that outputs video and audio to notify the worker of various information. In this embodiment, the traveling system device group MA1 includes mechanisms such as a steering actuator, engine EN, transmission, and brakes, and the working system device group MA2 includes mechanisms such as a PTO clutch, PTO transmission, braking device, and hydraulic cylinder a25.

The communication processing unit c2 is a communication mechanism that connects to an external device that is physically separated from the control device C via the network NW and exchanges information through communication. In this embodiment, the communication processing unit c2 is connected to the operation terminal T and is capable of sending and receiving information.

The operation terminal T is an information terminal equipped with a communication control unit t1, a display unit t2, and an operation unit t3, and has the functions of a computer system and a user interface for inputting the conditions necessary for the automatic driving realized by the control device C. For example, the communication control unit t1 is an information processing device including a CPU, ROM, RAM, etc., the display unit t2 is a liquid crystal panel, and the operation unit t3 is a touch panel, buttons, etc.

The operation terminal T also includes an area selection unit t4 for setting the work area R, which will be described later. This area selection unit t4 is a program that displays information required to set the work area R on the display unit t2 in response to a request from the control device C, accepts input of information required to define the position, size, range, etc. of the work area R via the operation unit t3, and returns information regarding the work area R that is determined based on the input information selected and determined by the worker to the control device C.

The input processing unit c3 is a mechanism that receives information input from a connected external device and is capable of acquiring various information such as positioning information and detection information. In this embodiment, the input processing unit c3 is connected to a positioning device AN, a traveling system detection sensor SN1 including a steering angle detection means, and a work system detection sensor SN2 that detects the operation, posture, and other conditions of the work machine WM.

The control device C also includes a driving control unit c4 that controls the driving of the work vehicle A, an information storage unit c5 that stores various information, and a route management unit c6 that performs processing related to the target driving route L.

The driving control unit c4 is a mechanism including a program and various circuits that control the driving of the work vehicle A during automatic driving (automatic steering) and manual driving (manual steering), and includes an automatic driving control unit c41 that controls the driving system equipment group MA1 during automatic driving, and a manual driving control unit c42 that controls the driving system equipment group MA1 during manual driving.

The automatic driving control unit c41 includes a vehicle position calculation unit c43 that calculates the vehicle position by acquiring positioning information (position information) from the positioning device AN, a vehicle orientation calculation unit c44 that calculates the vehicle orientation, a deviation calculation unit c45 that calculates a deviation, and a steering angle calculation unit c46 that calculates a steering angle from the detection information of the driving system detection sensor group SN1. The automatic driving control unit c41 configured in this manner calculates a deviation using the deviation calculation unit c45, calculates an appropriate steering angle of the steering wheel ST for the work vehicle A to travel along the target driving path L based on the calculated deviation, and controls the steering actuator to achieve the calculated steering angle, thereby enabling the work vehicle A to travel automatically.

The information storage unit c5 is a storage device capable of storing various information, and is, for example, a hard disk drive (HDD) or a solid state drive (SSD). The information storage unit c5 includes a field information storage unit c51 that stores information about the field, a route information storage unit c52 that stores information about the driving route during automatic driving, and a work information storage unit c53 that stores information about work.

The field information storage unit c51 stores information such as field information (information such as the size, shape, and map position of the field to be worked on, and the position data of the ridges that define the boundary line of the field), and work area information that defines the work area R (area to be worked on) within the field.

The route information storage unit c52 stores information related to the target driving route L and information such as the operation costs of the target driving route L (the driving distance, fuel consumption, operation time, etc. corresponding to the target driving route L).

The work information storage section c53 stores information about the work width W preset by the worker, the type of work (cultivation, sowing, etc.), etc.

The route management unit c6 is a program that manages (calculates, modifies, sets, etc.) the target driving route L, and includes an area setting unit c61, a route calculation unit c62, a route correction unit c63, an unworked area calculation unit c64, an inappropriate route exclusion unit c65, a work cost calculation unit c66, and a route setting unit c67.

Figure 3 is an explanatory diagram for explaining the target driving route L of the work vehicle A, and Figure 4 is an explanatory diagram showing the flow of data related to setting the target driving route L of the work vehicle A. Next, the functions of the area setting unit c61 and the route calculation unit c62 will be explained based on Figures 3 and 4.

The area setting unit c3 acquires field information from the field information storage unit c51 and sets a work area R within the field H. As shown in FIG. 3, this work area R is a substantially rectangular area whose position, size, and range are determined within the field H based on input information from the operation unit t3. When the area setting unit c3 acquires the field information, it requests input from the operation terminal T, defines the work area R based on the input information, and passes information about the work area R together with the field information to the path calculation unit c62 (see FIG. 4).

The path calculation unit c62 acquires information related to the work area R, field information, and information related to the work width W, and calculates a target travel path L within the defined work area R. Here, the calculation of the target travel path L is performed, for example, according to the following design procedure.

First, the working area R is divided into a headland traveling area R1 where the work is performed by traveling in a circular manner, and a straight-line traveling area R2 where the work is performed by traveling in a straight line. Here, the headland traveling area R1 is set as a frame-shaped area having a working width W, and a rectangular straight-line traveling area R2 is set inside the headland traveling area R1.

Next, a headland travel path l1 that travels in a circular manner within the headland travel area R1 is designed. Next, multiple straight travel paths l2 that travel in a straight line within the straight-line travel area R2 are designed. A predetermined overlap width V is provided between the straight-line travel paths l2 so that the working width W overlaps when the straight-line travel paths l2 are traveling.

Next, a non-work route l3 is designed, which is a route where no work is performed, for moving between the straight-line travel routes l2 in a single stroke and for moving from the straight-line travel route l2 to the headland travel route l1. At this time, the order of travel of the headland travel route l1 and the straight-line travel route l2 is also determined. The direction of the arrows of the straight-line travel route l2 and the straight-line travel route l2 shown in FIG. 3 indicates the direction of travel of the work vehicle A, and the numbers in circles shown near the ends of the arrows indicate the order of travel during automatic travel. The target travel route L is calculated by the above design procedure. The route calculation unit c62 passes information about the calculated target travel route L to the route correction unit c63 (see FIG. 4).

As shown in FIG. 3, the start of the straight-line travel path l2 on one end of the straight-line travel area R2 is the work start point Ps on the straight-line travel path l2 (the point where work is first started by the work machine WM), and the end of the straight-line travel path l2 on the other end is the work end point Pe (the point where work ends within the straight-line travel area R2). When the work vehicle A starts automatic travel, it is assumed that the work vehicle A has been moved to the vicinity of the work start point Ps. For ease of explanation, in the following, one end of the straight-line travel area R2 will be referred to as the right, and the other end of the straight-line travel area R2 will be referred to as the left.

The route correction unit c63 acquires information on the target driving route L, and when automatic driving starts, acquires information on the deviation from the deviation calculation unit c45 and calculates a corrected target driving route L based on the deviation between the vehicle position and the target driving route L. Here, the route correction unit c63 is configured to calculate multiple corrected target driving routes L using multiple correction methods (overlap width increase/decrease method, straight driving route addition method, and headland driving route addition method). The multiple correction methods will be described in detail later.

The unworked area calculation unit c64 calculates the unworked area R3 when the path correction unit c63 corrects the target driving path L. Here, the unworked area R3 refers to an area within the straight driving area R2 where no work is being performed, as shown by the shaded area in FIG. 5, assuming that the work vehicle A travels along the target driving path L while performing work within the working width W. Note that the colored areas within the working area R in FIG. 5 indicate areas where work is being performed.

The inappropriate route exclusion unit c65 acquires information about the proposed target travel route from the route correction unit c63, and performs the function of excluding inappropriate target travel routes L from the proposed target travel route. For example, an inappropriate target travel route L refers to a target travel route L that deviates from a field or has a straight line travel route l2 outside the straight line travel region R2.

The operation cost calculation unit c66 obtains the target driving route plan from which the inappropriate target driving route L has been excluded from the inappropriate route exclusion unit c65, and calculates the operation cost for each target driving route L. Next, the target driving route plan and information related to the operation cost are passed to the route setting unit c67 (see FIG. 4).

The route setting unit c67 acquires information on the proposed target driving route and the work cost from the work cost calculation unit c66, transmits them to the operation terminal T, displays the proposed target driving route and the work cost on the display unit t2, and has the operator select and determine one of the proposed target driving routes L using the operation unit t3. The route setting unit c67 acquires input information from the operation terminal T, and sets the target driving route L determined by the operator in the control device C as the target driving route L along which the work vehicle A will automatically travel. At this time, the determined target driving route L is stored in the route information storage unit c23 and transferred to the automatic driving control unit c41, and automatic driving is started (see FIG. 4). By displaying the proposed target driving route and the work cost on the display unit t2, the target driving route L, the work cost, and straightness are visualized, and can be used as information for the operator's decision.

<3. How to correct the target driving route (overlap width increase/decrease method)>
FIG. 6 is an explanatory diagram showing a procedure for correcting the target travel route L using the overlap width increase/decrease method.
As shown in Fig. 6(a), the correction procedure will be described for the case where the vehicle position when the work vehicle A starts automatic traveling has a deviation d to the left in the direction perpendicular to the stripe direction (left-right direction on the paper in Fig. 6) (when the left deviation point PL in Fig. 6 is the vehicle position) and the case where the vehicle position has a deviation d to the right (when the right deviation point PR in Fig. 6 is the vehicle position) with respect to the work start point Ps. Note that the stripe direction (up-down direction on the paper in Fig. 6) and the deviation in the orientation are not taken into consideration. The stripe direction refers to the direction parallel to the straight-line travel path l2.

As shown in FIG. 6(b), if the vehicle position has a deviation d to the left, the straight path l2 is translated in a direction that increases the overlap width V, and the target travel path L is corrected so that the new work start point Ps' is in the straight-ahead direction (stripe direction) of the vehicle position.

As shown in FIG. 6(c), if the vehicle position has a deviation d to the right, the straight path l2 is translated in a direction that reduces the overlap width V, and the target travel path L is corrected so that the new work start point Ps' is in the straight-ahead direction (stripe direction) of the vehicle position. This method makes it possible to easily correct the target travel path L without increasing work costs.

<4. How to correct the target driving route (method of adding a straight driving route)>
FIG. 7 is an explanatory diagram showing a procedure for correcting the target travel route L using the straight line travel route addition method.
As shown in Fig. 7(a), the correction procedures will be described for the case where the vehicle position when the work vehicle A starts automatic traveling with respect to the work start point Ps is the left deviation point PL and the case where the vehicle position is the right deviation point PR. Note that the deviation in the line direction (the up and down direction on the paper in Fig. 7) and the azimuth direction are not taken into consideration.

As shown in FIG. 7(b), if the vehicle position has a deviation d to the left, all straight-line paths l2 are moved in parallel to the left (downstream in the work direction) by the deviation d, and the straight-line paths l2 are corrected so that the new work start point Ps' is in the straight-line direction (row direction) of the vehicle position. At this time, if an unworked area R3 does not occur, the correction of the target travel path L is completed. If an unworked area R3 occurs, as shown in FIG. 7(c), a straight-line path l2 is added to the right (upstream in the work direction) and the unworked area R3 is corrected to eliminate it. At this time, the travel order of the straight-line travel path l2 and the headland travel path l3 is also changed so that the travel order is optimized. This completes the correction of the target travel path L. According to this method, it is possible to accurately correct the target travel path so that the work start point Ps' of the target travel path L is in the row direction of the vehicle position.

As shown in FIG. 7(d), if the vehicle position has a deviation d to the right, all straight-line paths l2 are moved in parallel to the right (upper side of the work direction) by the deviation d, and the straight-line paths l2 are corrected so that the new work start point Ps' is in the straight-line direction (row direction) of the vehicle position. At this time, if an unworked area R3 does not occur, the correction of the target travel path L is completed. If an unworked area R3 occurs, as shown in FIG. 7(e), a straight-line path l2 is added to the left side (lower side of the work direction) and the unworked area R3 is corrected to eliminate it. This makes it possible to prevent an area that is not worked from occurring as a result of correcting the target travel path L. At this time, the travel order is also changed so that the travel order of the straight-line travel path l2 and the headland travel path l3 is optimized. This completes the correction of the target travel path L. In this way, by changing the travel order of the target travel path L, it is possible to prevent a situation in which a discrepancy occurs in the travel order and to travel efficiently.

<5. How to correct the target driving route (how to add a headland driving route)>
FIG. 8 is an explanatory diagram showing a procedure for correcting the target travel route L using the headland travel route addition method.
As shown in Fig. 8(a), the correction procedures will be described for the case where the vehicle position when the work vehicle A starts automatic traveling with respect to the work start point Ps is the left deviation point PL and the case where the vehicle position is the right deviation point PR. Note that the deviation in the line direction (the up and down direction on the paper in Fig. 8) and the azimuth direction are not taken into consideration.

As shown in FIG. 8(b), if the vehicle position has a deviation d to the left, all straight-line paths l2 are moved in parallel to the left (downstream of the work direction) by the deviation d, and the straight-line paths l2 are corrected so that the new work start point Ps' is in the straight-line direction (row direction) of the vehicle position. At this time, if an unworked area R3 does not occur, the correction of the target travel path L is completed. If an unworked area R3 occurs, as shown in FIG. 8(c), a further headland travel path l2 is added inside the headland travel path l1, and the unworked area R3 is corrected to eliminate it. This makes it possible to prevent the occurrence of an area that is not worked on as a result of correcting the target travel path L. At this time, the travel order of the straight-line travel path l2 and the headland travel path l3 is also changed so that the travel order is optimized. This completes the correction of the target travel path L.

As shown in FIG. 8(d), if the vehicle position has a deviation d to the right, all straight-line paths l2 are translated to the right (upstream of the work direction) by the deviation d, and the straight-line paths l2 are corrected so that the new work start point Ps' is in the straight-line direction (row direction) of the vehicle position. At this time, if an unworked area R3 does not occur, the correction of the target travel path L is completed. If an unworked area R3 occurs, as shown in FIG. 8(e), a further headland travel path l2 is added inside the headland travel path l1, and the correction is made to eliminate the unworked area R3. At this time, the travel order of the straight-line travel path l2 and the headland travel path l3 is also changed so that the travel order is optimized. This completes the correction of the target travel path L.

6. Method for correcting target driving route (modified example)
FIG. 9 is an explanatory diagram showing a procedure for correcting the target travel path L according to a modified example.
7(d) and 7(e) show a configuration in which, if an unworked area R3 occurs, a straight line path 12 is added to the left side (downstream in the working direction) to correct the unworked area R3, but as shown in Fig. 9(b) and 9(c), if an unworked area R3 occurs on the left side, each straight line path 12 may be translated in the direction that reduces the overlap width V, thereby correcting the unworked area R3 to disappear. With this method, regardless of whether an unworked area R3 occurs on the left or right side, the unworked area R3 can be successfully eliminated.

By using the above method, the path correction unit c63 corrects the straight-line driving path l2 of the target driving path L based on the vehicle's position at the start of automatic driving so that the new work start point Ps' is in the line direction from the vehicle's position. Therefore, the work vehicle A according to this embodiment can travel straight to the work start point Ps' immediately after the start of automatic driving, and then move onto the straight-line driving path l2 while continuing to travel straight to start work. In other words, immediately after the start of automatic driving, it is only necessary to adjust the orientation of the work vehicle A to stably move onto a trajectory on the straight-line driving path l2. This improves straight-line driving immediately after the start of automatic driving, and improves work accuracy.

<7. Processing when automatic driving starts>
Fig. 10 is a flowchart showing an example of the processing of the control device C when the automatic driving starts. Fig. 11 is a flowchart showing an example of the processing of the target driving route correction processing of Fig. 10. Next, the processing of the control device C when the automatic driving starts will be described with reference to Figs. 10 and 11.

As shown in FIG. 10, before starting automatic driving, the control device C acquires field information from the field information storage unit c51 (step S101), and sets the work area R by the area setting unit c61 (step S102).

Next, the target driving route L is calculated by the target route calculation unit c62, and information about the calculated target driving route L is stored in the route information storage unit c52 (step S103).

Next, when the control device C receives an instruction to start automatic driving through a predetermined operation by the operator (Yes in step S104), it acquires a deviation from the deviation calculation unit c45 and starts a target driving route correction process to correct the target driving route based on the acquired deviation.

When the target driving route correction process is started, as shown in FIG. 11, the control device C calculates a target driving route L corrected by the overlap width increase/decrease method using the route correction unit c63 and the unworked area calculation unit c64 (step S201), calculates a target driving route L corrected by the straight driving route addition method (step S202), and calculates a target driving route L corrected by the headland driving route addition method (step S203). Among these calculated multiple target driving routes L (target driving route proposals), the inappropriate target driving routes L are excluded by the inappropriate route exclusion unit c65 (step S204).

Next, the operation cost is calculated for each of the target driving routes L included in the proposed target driving route (step S205).

Once the work cost has been calculated, input from the worker is accepted from the information terminal T, and the target driving route L selected and determined by the worker from among the proposed target driving routes is set in the route information storage unit c52 as the target driving route L along which the work vehicle A will ultimately travel (step S206).

Returning to FIG. 10, the automatic driving control unit c41 then starts automatic driving according to the set target driving route L (step S107).

8. Other embodiments
The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the invention described in the claims, and it goes without saying that these modifications are also included within the scope of the present invention.

In the above embodiment, the route setting unit c67 displays the work costs of multiple target driving routes L included in the proposed target driving route on the display unit t2, and the worker selects and decides one target driving route L using the operation unit t3. However, it may be configured to first present the most efficient target driving route L to the worker in terms of driving distance, work time, straightness, and fuel consumption.

Furthermore, the system may be configured with a sorting function that allows the operator to select which of the following to prioritize: travel distance, work time, straightness, or fuel consumption.

The path correction unit c33 may be configured to not make correction of the target travel path L effective unless the deviation is within a predetermined range (one process, within the working width W, etc.). Furthermore, when the correction of the target travel path L is not effective, a pop-up may be displayed on the display unit t2 to the effect that the correction of the target travel path L has failed.

The path correction unit c33 may be configured to acquire the work content from the work information storage unit c53, and the correction of the target travel path L by the path correction unit c33 may be configured not to be effective in the case of a specified work content. Since there are some works, such as tillage and soiling, in which it is not appropriate to correct the target travel path L, such a configuration makes it possible to avoid changing the target travel path L in works in which it is undesirable to change it.

In addition, in the above embodiment, the operation terminal T is connected to the control device C via the network NW and configured as a device external to the work vehicle A, but it may also be provided on the vehicle side (e.g., inside the cabin a15) by connecting to the control device C via the communication bus BA.

A Work vehicle a1 Traveling vehicle body a11 Bonnet a12 Transmission case a13 Front wheel a14 Rear wheel a15 Cabin a21 Hydraulic cylinder case a22 Lift arm a23 Top link a24 Lower link a25 Hydraulic cylinder BA Communication bus C Control device L Target travel path l1 Headland travel path l2 Straight travel path l3 Non-work path R Work area R1 Headland travel area R2 Straight travel area R3 Non-work area T Operation terminal V Overlap width W Work width AS Navigation satellite 225 Electric display unit 226 Liquid crystal display unit 227 Direction notification unit 227r Right direction display unit 227l Left direction display unit 228 Input operation unit 228a Rotary switch 228b Push button switch 229 Audio output unit 301 Seedling planting unit 302 Seedling placement table 303 Seedling planting device 304 Float 305 Seedling loading surface 306 Planting rod 307 Rotary case 308 Planting transmission case 309 Hydraulic rolling cylinder 310 Ground leveling rotor 311 Ground leveling rotor adjustment mechanism BA Communication bus C Control device L Target travel path l1 Straight travel path l2 Turning path T Information terminal

Claims (2)

A work vehicle that automatically travels in a field along a target travel route,
A control device that acquires position information during automatic driving to calculate a vehicle position and automatically steers the vehicle along a set target driving route , and a farm field information storage unit that stores farm field information ,
The control device includes an area setting unit that defines and sets a work area in the field based on the field information acquired from the field information storage unit and input information input by an operator;
a route calculation unit that calculates the target driving route within the working area set by the area setting unit; and a route correction unit that calculates a deviation between a working start point of the calculated target driving route and a vehicle position in a direction perpendicular to a line direction at the start of autonomous driving, and corrects the calculated target driving route .
and an unworked area calculation unit that calculates an unworked area within the set working area in which no work is expected to be performed, using a preset working width of the work implement and information on the calculated target traveling path during the process of correcting the calculated target traveling path by the path correction unit ,
the route calculation unit is configured to divide the set working area into a headland traveling area in which work is performed by traveling in a circular manner, and a straight-line traveling area in which work is performed by traveling in a straight line, set the headland traveling area to a frame-shaped area having the working width, and set the straight-line traveling area inside the headland traveling area, so that a headland traveling path that travels in a circular manner within the headland traveling area and a plurality of straight-line traveling paths that travel in a straight line within the straight-line traveling area are included in the target traveling path; and
When the calculated target driving route is corrected by the route correction unit, the multiple straight driving routes included in the calculated target driving route are translated by an amount of deviation in a direction perpendicular to the row direction, and then the unworked area calculation unit calculates the unworked area to determine whether or not an unworked area has occurred, and if it is determined that an unworked area has occurred, the calculated target driving route is corrected so as to add a new headland driving route inside the headland driving route . The work vehicle according to claim 1, characterized in that, when a new headland travel route is added to the calculated target travel route, the route correction unit changes a travel order of the straight line travel routes and the headland travel routes included in the calculated target travel route .