Path generation method, path generation program, and path generation system

Abstract

To provide a path generation method, a path generation program, and a path generation system that can generate a target path including a turning path for making it possible to perform work while turning.SOLUTION: In an automatic traveling system 1, a setting processing unit 212 sets a first reference line for serving as a reference at the time of generating a target path, and including a plurality of first partial straight lines. A generation processing unit 213 individually moves each of the plurality of first partial straight lines in parallel by a predetermined distance, connects each of a plurality of second partial straight lines corresponding to each of the plurality of first straight lines after the parallel movement, and generates the target path.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a technique for generating a target path for automatically driving a work vehicle.

Background Art

[0002] Conventionally, in a field, a work vehicle that automatically travels according to a preset target path is known. For example, the work vehicle automatically travels according to target paths set in each of the inner peripheral area of the central part of the field and the outer peripheral area (headland area) of the outer peripheral part of the field (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, when a work vehicle performs work in a field, there are cases where the work is performed not only while traveling in a straight line but also while traveling in a curved shape (turning). In order for a work vehicle to perform work while turning, it is necessary to set a target path including a turning path that enables work while turning. However, in the conventional technology, it is not assumed to perform work while turning in automatic driving, and it is difficult to generate a target path including a turning path that enables work while turning.

[0005] An object of the present invention is to provide a path generation method, a path generation program, and a path generation system capable of generating a target path including a turning path that enables work while turning.

Means for Solving the Problems

[0006] The path generation method according to the present invention is a path generation method for generating a target path for automatically driving a work vehicle in a work area. The path generation method includes setting a first reference line serving as a reference when generating the target path, the first reference line including a plurality of first partial straight lines; individually translating each of the plurality of first partial straight lines by a predetermined distance; and connecting each of the plurality of second partial straight lines corresponding to each of the plurality of first partial straight lines after the translation to generate the target path.

[0007] The path generation program according to the present invention is a path generation program for generating a target path for automatically driving a work vehicle in a work area. The path generation program is a path generation program for causing one or more processors to execute setting a first reference line serving as a reference when generating the target path, the first reference line including a plurality of first partial straight lines; individually translating each of the plurality of first partial straight lines by a predetermined distance; and connecting each of the plurality of second partial straight lines corresponding to each of the plurality of first partial straight lines after the translation to generate the target path.

[0008] The path generation system according to the present invention is a path generation system for generating a target path for automatically driving a work vehicle in a work area. The path generation system includes a setting processing unit and a generation processing unit. The setting processing unit sets a first reference line serving as a reference when generating the target path, the first reference line including a plurality of first partial straight lines. The generation processing unit individually translates each of the plurality of first partial straight lines by a predetermined distance, and connects each of the plurality of second partial straight lines corresponding to each of the plurality of first partial straight lines after the translation to generate the target path.

Advantages of the Invention

[0009] According to the present invention, it is possible to provide a path generation method, a path generation program, and a path generation system capable of generating a target path including a turning path that can perform work while turning.

Brief Description of the Drawings

[0010]

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DETAILED DESCRIPTION OF THE INVENTION

[0011] The following embodiments are examples embodying the present invention and do not limit the technical scope of the present invention.

[0012] As shown in FIG. 1, the automatic driving system 1 according to an embodiment of the present invention includes a work vehicle 10 and an operation terminal 20. The work vehicle 10 and the operation terminal 20 can communicate via a communication network N1. For example, the work vehicle 10 and the operation terminal 20 can communicate via a mobile phone line network, a packet line network, or a wireless LAN. The automatic driving system 1 is an example of the route generation system of the present invention.

[0013] In the present embodiment, the case where the work vehicle 10 is a tractor will be described as an example. As another embodiment, the work vehicle 10 may be a combine, a rice transplanter, a construction machine, a snowplow, or the like. The work vehicle 10 is configured to be able to automatically travel along a preset target route within a field F (see FIG. 4).

[0014] For example, an operator registers a field F to be worked and sets a target route for automatically driving the work vehicle 10 with respect to the field F. The work vehicle 10 automatically travels along a preset target route with respect to the field F based on the position information of the current position of the work vehicle 10 acquired by the positioning unit 16. Further, the work vehicle 10 performs a predetermined work while automatically traveling within the field F.

[0015] The operation terminal 20 is a portable terminal capable of remotely operating the work vehicle 10 and is configured by, for example, a tablet terminal, a notebook personal computer, a smartphone, or the like. The operator can perform setting operations on various setting items on the operation terminal 20. For example, the operator operates the operation terminal 20 to register the field F or set a target route for the registered field F. Further, the operation terminal 20 displays information such as the work status and the traveling status of the work vehicle 10 during automatic driving. The operator can grasp the work status and the traveling status on the operation terminal 20.

[0016] Incidentally, when the work vehicle 10 performs work in the field F, it may perform work not only while traveling in a straight line but also while traveling (turning) in a curve. For example, when a part of the outer shape of the field F (such as a corner) is non-rectangular such as diagonal or curved, the work vehicle 10 may be made to perform work while turning in a curve along the shape of the part. In order for the work vehicle 10 to perform work while turning, it is necessary to set a target path including a turning path (a turning path for work) that enables work while turning. However, in the conventional technology, it is not assumed to perform work while turning in automatic driving, and it is difficult to generate a target path including a turning path that enables work while turning. On the other hand, as described below, the automatic driving system 1 according to the present embodiment has a configuration capable of generating a target path including a turning path that enables work while turning.

[0017] [Work vehicle 10] As shown in FIGS. 1 and 2, the work vehicle 10 includes a vehicle control device 11, a storage unit 12, a traveling device 13, a working machine 14, a communication unit 15, a positioning unit 16, and the like. The vehicle control device 11 is electrically connected to the storage unit 12, the traveling device 13, the working machine 14, the positioning unit 16, and the like. Note that the vehicle control device 11 and the positioning unit 16 may be capable of wireless communication.

[0018] The communication unit 15 is a communication interface for connecting the work vehicle 10 to the communication network N1 by wire or wirelessly and executing data communication according to a predetermined communication protocol with an external device (such as the operation terminal 20) via the communication network N1.

[0019] The storage unit 12 is a non-volatile storage unit such as an HDD (Hard Disk Drive) or an SSD (Solid State Drive) that stores various types of information. The storage unit 12 stores a control program for causing the vehicle control device 11 to execute various processes. For example, the control program is non-temporarily recorded on a computer-readable recording medium such as a CD or a DVD, read by a predetermined reading device (not shown), and stored in the storage unit 12. Note that the control program may be downloaded from a server (not shown) to the work vehicle 10 via the communication network N1 and stored in the storage unit 12. Also, the storage unit 12 stores data such as the target route generated in the operation terminal 20.

[0020] The traveling device 13 is a driving unit that causes the work vehicle 10 to travel. As shown in FIG. 2, the traveling device 13 includes an engine 131, front wheels 132, rear wheels 133, a transmission 134, a front axle 135, a rear axle 136, a steering wheel 137, and the like. Note that the front wheels 132 and the rear wheels 133 are provided on the left and right sides of the work vehicle 10, respectively. Also, the traveling device 13 is not limited to a wheel type including the front wheels 132 and the rear wheels 133, and may be a crawler type including crawlers provided on the left and right sides of the work vehicle 10.

[0021] The engine 131 is a drive source such as a diesel engine or a gasoline engine that is driven using fuel supplied from a fuel tank (not shown). The traveling device 13 may include an electric motor as a drive source together with the engine 131 or instead of the engine 131. Note that a generator (not shown) is connected to the engine 131, and electric power is supplied from the generator to electrical components such as the vehicle control device 11 and the positioning unit 16 provided in the work vehicle 10 and a battery. Note that the battery is charged by the electric power supplied from the generator. Then, electrical components such as the vehicle control device 11 and the positioning unit 16 provided in the work vehicle 10 can be driven by the electric power supplied from the battery even after the engine 131 stops.

[0022] The driving force of the engine 131 is transmitted to the front wheels 132 via the transmission 134 and the front axle 135, and is transmitted to the rear wheels 133 via the transmission 134 and the rear axle 136. Further, the driving force of the engine 131 is also transmitted to the working machine 14 via a PTO shaft (not shown). When the work vehicle 10 performs automatic traveling, the traveling device 13 performs a traveling operation according to an instruction from the vehicle control device 11. Further, the traveling device 13 decelerates or stops the work vehicle 10 according to an instruction from the vehicle control device 11.

[0023] The working machine 14 is, for example, a tiller, a lawn mower, a plow, a fertilizer applicator, a sprayer (chemical sprayer), a harrow, or a seeder, etc., and is detachable from the work vehicle 10. Thereby, the work vehicle 10 can perform various works using each of the working machines 14. FIG. 2 shows a case where the working machine 14 is a tiller. For example, the working machine 14 is mounted behind the work vehicle 10. The work vehicle 10 performs a tilling operation by mounting the working machine 14 at the rear and traveling in the field F.

[0024] The working machine 14 may be supported by the work vehicle 10 so as to be liftable by a lifting mechanism (not shown). The vehicle control device 11 can control the lifting mechanism to lift and lower the working machine 14. For example, the vehicle control device 11 lowers the working machine 14 when the work vehicle 10 travels straight forward in the forward direction in the field F, and raises the working machine 14 when the work vehicle 10 travels straight backward or turns in the field F. Further, when the work vehicle 10 performs work on a turning path, the vehicle control device 11 lowers the working machine 14 when the work vehicle 10 turns on the turning path. Further, when the vehicle control device 11 acquires a work stop instruction, the vehicle control device 11 outputs a work stop command to the working machine 14. For example, the vehicle control device 11 acquires the stop instruction from the operation terminal 20 when the operator performs a stop instruction operation on the operation terminal 20. When the vehicle control device 11 acquires a work stop instruction, the vehicle control device 11 stops driving the PTO shaft to stop the work of the working machine 14.

[0025] The steering wheel 137 is an operation unit operated by an operator or the vehicle control device 11. For example, in the traveling device 13, according to the operation of the steering wheel 137 by the vehicle control device 11, the angle of the front wheels 132 is changed by a hydraulic power steering mechanism (not shown) or the like, and the traveling direction of the work vehicle 10 is changed.

[0026] In addition to the steering wheel 137, the traveling device 13 includes a shift lever (not shown), an accelerator, a brake, etc. that are operated by the vehicle control device 11. In the traveling device 13, according to the operation of the shift lever by the vehicle control device 11, the gear of the transmission 134 is switched to a forward gear or a reverse gear, etc., and the traveling mode of the work vehicle 10 is switched to forward or reverse, etc. Also, the vehicle control device 11 controls the rotational speed of the engine 131 by operating the accelerator. Further, the vehicle control device 11 operates the brake to brake the rotation of the front wheels 132 and the rear wheels 133 using an electromagnetic brake.

[0027] The positioning unit 16 is a communication device including a positioning control unit 161, a storage unit 162, a communication unit 163, and a positioning antenna 164 (see FIG. 1), etc. For example, as shown in FIG. 2, the positioning unit 16 is provided on the upper part of the cabin 138 where the operator rides. Also, the installation location of the positioning unit 16 is not limited to the cabin 138. Furthermore, the positioning control unit 161, the storage unit 162, the communication unit 163, and the positioning antenna 164 of the positioning unit 16 may be distributed and arranged at different positions in the work vehicle 10. As described above, the battery is connected to the positioning unit 16, and the positioning unit 16 can operate even when the engine 131 is stopped. Also, as the positioning unit 16, for example, a mobile phone terminal, a smartphone, a tablet terminal, a quantum compass, etc. may be substituted.

[0028] The positioning control unit 161 is a computer system including one or more processors and a storage memory such as a non-volatile memory and a RAM. The storage unit 162 is a non-volatile memory or the like that stores a program for causing the positioning control unit 161 to execute positioning processing, and data such as positioning information and movement information. For example, the program is non-temporarily recorded on a computer-readable recording medium such as a CD or a DVD, read by a predetermined reading device (not shown), and stored in the storage unit 162. Note that the program may be downloaded from a server (not shown) to the positioning unit 16 via the communication network N1 and stored in the storage unit 162.

[0029] The communication unit 163 is a communication interface for connecting the positioning unit 16 to the communication network N1 by wire or wirelessly and performing data communication according to a predetermined communication protocol with an external device such as a base station server via the communication network N1.

[0030] The positioning antenna 164 is an antenna that receives radio waves (GNSS signals) transmitted from satellites.

[0031] The positioning control unit 161 calculates the current position of the work vehicle 10 based on the GNSS signals received by the positioning antenna 164 from satellites. For example, when the work vehicle 10 automatically travels within the farm field F, when the positioning antenna 164 receives radio waves (transmission time, orbital information, etc.) transmitted from each of a plurality of satellites, the positioning control unit 161 calculates the distances between the positioning antenna 164 and each satellite, and calculates the current position (latitude and longitude) of the work vehicle 10 based on the calculated distances. Further, the positioning control unit 161 may perform positioning by a real-time kinematic method (RTK-GNSS positioning method (RTK method)) of calculating the current position of the work vehicle 10 using correction information corresponding to a base station (reference station) close to the work vehicle 10. Thus, the work vehicle 10 performs automatic travel using the positioning information by the RTK method. Note that the current position of the work vehicle 10 may be the same position as the positioning position (for example, the position of the positioning antenna 164), or may be a position deviated from the positioning position. Note that the positioning control unit 161 may calculate (perform positioning of) the current position of the work vehicle 10 using a quantum compass.

[0032] The vehicle control device 11 includes control devices such as a CPU, a ROM, and a RAM. The CPU is a processor that executes various arithmetic processes. The ROM is a non-volatile storage unit in which control programs such as BIOS and an OS for causing the CPU to execute various arithmetic processes are stored in advance. The RAM is a volatile or non-volatile storage unit that stores various information, and is used as a temporary storage memory for various processes executed by the CPU. Then, the vehicle control device 11 controls the work vehicle 10 by causing the CPU to execute various control programs stored in advance in the ROM or the storage unit 12.

[0033] Specifically, as shown in FIG. 1, the vehicle control device 11 includes various processing units such as a traveling processing unit 111. The vehicle control device 11 functions as the various processing units by executing various processes according to the control program using the CPU. Further, some or all of the processing units may be configured by electronic circuits. The control program may be a program for causing a plurality of processors to function as the processing units.

[0034] The traveling processing unit 111 controls the traveling of the work vehicle 10. For example, when the traveling mode of the work vehicle 10 is automatic traveling (automatic traveling mode), the traveling processing unit 111 automatically travels the work vehicle 10 based on the position information (positioning information) indicating the current position of the work vehicle 10 measured by the positioning unit 16. For example, when the work vehicle 10 satisfies the start condition of automatic traveling and acquires a work start instruction from the operator, the traveling processing unit 111 starts the automatic traveling of the work vehicle 10 based on the positioning information. Further, the traveling processing unit 111 automatically travels the work vehicle 10 from the traveling start position to the traveling end position according to a target route generated and set in advance on the operation terminal 20. For example, the traveling processing unit 111 travels the work vehicle 10 according to a plurality of work routes for causing the work vehicle 10 to perform a predetermined work and a plurality of non-work routes connecting between the work routes included in the target route.

[0035] When the traveling mode of the work vehicle 10 is manual traveling (manual traveling mode), it is possible to manually travel the work vehicle 10 based on the operation of the operator (manual steering). For example, the traveling processing unit 111 acquires operation information corresponding to driving operations such as a steering operation, a shift operation, a traveling direction switching operation, and a brake operation by the operator, and causes the traveling device 13 to execute a traveling operation based on the operation information. For example, when registering the field to be worked, the operator manually travels (teaching traveling) along the outer peripheral portion of the area to be worked within a predetermined area while boarding the work vehicle 10. The operator may lower the work implement 14 and execute a predetermined work (for example, tilling work) while the work vehicle 10 is being taught to travel.

[0036] [Operation terminal 20] As shown in FIG. 1, the operation terminal 20 is an information processing device including an operation control unit 21, a storage unit 22, an operation display unit 23, a communication unit 24, and the like. The operation terminal 20 may be configured by a mobile terminal such as a tablet terminal or a smartphone.

[0037] The communication unit 24 is a communication interface for connecting the operation terminal 20 to the communication network N1 by wire or wirelessly and performing data communication according to a predetermined communication protocol with external devices such as one or more work vehicles 10 via the communication network N1.

[0038] The operation display unit 23 is a user interface including a display unit such as a liquid crystal display or an organic EL display for displaying various information, and an operation unit such as a touch panel, a mouse, or a keyboard for receiving operations. An operator can perform an operation of registering various information (work vehicle information, field information, work information, etc., described later) by operating the operation unit on the operation screen displayed on the display unit. In addition, the operator can perform an operation of instructing the start of work, a travel stop instruction, etc. for the work vehicle 10 by operating the operation unit. Further, the operator can grasp the traveling state of the work vehicle 10 that automatically travels in the field F along the target path based on the traveling locus and the captured image of the camera displayed on the operation terminal 20 at a location away from the work vehicle 10.

[0039] The storage unit 22 is a non-volatile storage unit such as an HDD or an SSD that stores various information. The storage unit 22 stores a path generation program for causing the operation control unit 21 to execute a path generation process (see FIG. 12) described later and a control program for causing various control processes to be executed. For example, the path generation program is non-temporarily recorded on a computer-readable recording medium such as a CD or a DVD, and is read by a predetermined reading device (not shown) and stored in the storage unit 22. Note that the path generation program may be downloaded from a server (not shown) to the operation terminal 20 via the communication network N1 and stored in the storage unit 22.

[0040] The operation control unit 21 includes control devices such as a CPU, a ROM, and a RAM. The CPU is a processor that executes various arithmetic processes. The ROM is a non-volatile storage unit in which control programs such as BIOS and OS for causing the CPU to execute various arithmetic processes are stored in advance. The RAM is a volatile or non-volatile storage unit that stores various information and is used as a temporary storage memory (working area) for various processes executed by the CPU. Then, the operation control unit 21 controls the operation terminal 20 by causing the CPU to execute various control programs stored in advance in the ROM or the storage unit 22.

[0041] As shown in FIG. 1, the operation control unit 21 includes various processing units such as a registration processing unit 211, a setting processing unit 212, a generation processing unit 213, and an output processing unit 214. Note that the operation control unit 21 functions as the various processing units by causing the CPU to execute various processes according to the route generation program. Also, some or all of the processing units may be configured by electronic circuits. Note that the route generation program may be a program for causing a plurality of processors to function as the processing units.

[0042] The registration processing unit 211 registers various setting information for causing the work vehicle 10 to execute automatic driving. Specifically, the registration processing unit 211 registers information regarding the work vehicle 10 (hereinafter referred to as work vehicle information). The registration processing unit 211 registers the information by the operator performing an operation of registering the information on the operation terminal 20 regarding the type (model) of the work vehicle 10, the position where the positioning antenna 164 is attached to the work vehicle 10, the type of the work implement 14, the size and shape of the work implement 14, the position of the work implement 14 with respect to the work vehicle 10, the vehicle speed and engine speed during operation of the work vehicle 10, the vehicle speed and engine speed during turning of the work vehicle 10, and the like.

[0043] For example, the registration processing unit 211 causes the operation display unit 23 to display the menu screen D1 shown in FIG. 5. The operator selects, for example, "Work implement registration" on the menu screen D1 to register work implement information regarding the work implement 14.

[0044] In addition, the registration processing unit 211 registers information related to the field F (hereinafter referred to as field information). The registration processing unit 211 registers the information by performing an operation of registering, on the operation terminal 20, information such as the position and shape of the field F, the traveling start position where the work starts, the traveling end position where the work ends, and the working direction. Note that the working direction means the direction in which the work vehicle 10 travels while the work machine 14 performs work in the working area excluding the non-working area from the field F. For example, the operator selects "Field Registration" on the menu screen D1 to register the field information.

[0045] The information on the position and shape of the field F can be automatically acquired, for example, by the operator boarding the work vehicle 10 and driving it to go around once along the outer periphery of a predetermined area AR (see FIG. 3), and recording the transition of the position information of the positioning antenna 164 at that time.

[0046] Specifically, the registration processing unit 211 acquires the position information of the current position of the work vehicle 10 based on the positioning information measured by the positioning unit 16. When the registration processing unit 211 acquires the position information, it registers the position information in the storage unit 22. For example, when the operator manually drives (teaching driving) the work vehicle 10 in a predetermined area AR when registering the field (see FIG. 3), the registration processing unit 211 acquires the position information of the work vehicle 10 at a predetermined sampling interval. The black dot shown in FIG. 3 corresponds to the position information of each measurement point.

[0047] In addition, while the operator is performing teaching driving of the work vehicle 10, the work machine 14 may be lowered to perform a predetermined work. The registration processing unit 211 sequentially registers the position information of the work vehicle 10 while the work vehicle 10 is performing teaching driving.

[0048] When the teaching run is completed, the registration processing unit 211 registers the field based on the position information. For example, as shown in FIG. 4, the registration processing unit 211 obtains an approximate straight line connecting the driving trajectories (plots) traveled by the work vehicle 10, generates intersection points (complementary points a1 to a6) between the extension lines of adjacent approximate straight lines, and registers the area surrounded by the straight line connecting the generated complementary points a1 to a6 as the field F. Note that the operator can change the positions of the complementary points or add complementary points. In this way, the registration processing unit 211 registers the field F as the work target area based on the position information obtained by the manual driving operation of the work vehicle 10 by the operator.

[0049] In addition, the registration processing unit 211 registers information regarding how to specifically perform the work (hereinafter referred to as work information). The registration processing unit 211 is configured to be able to register, as work information, the presence or absence of cooperative work between the unmanned work vehicle 10 and the manned work vehicle 10, the skip count which is the number of work routes to be skipped when the work vehicle 10 turns at the headland, the width of the headland, and the width of the non-work area, etc. For example, the operator selects "Route Creation" on the menu screen D1 to register the information of the driving route.

[0050] The setting processing unit 212 sets a reference line (first reference line Ra) that serves as a reference when generating the target route of the work vehicle 10. Specifically, the setting processing unit 212 sets the first reference line Ra including a plurality of first partial straight lines (line segments) based on a plurality of position information obtained when registering the field. For example, the setting processing unit 212 sets the first reference line Ra based on the position information indicating the driving trajectory of the work vehicle 10 obtained by the manual driving operation (teaching driving operation) of the operator when registering the field. Hereinafter, in the field F shown in FIG. 4, the method of generating the target route corresponding to the area A1 where the work is performed while turning will be described as an example.

[0051] First, the setting processing unit 212 sets a second reference line Rb including partial curves (curve segments) based on a plurality of position information obtained when registering a farmland. Specifically, as shown in FIG. 6, the setting processing unit 212 sets the second reference line Rb by connecting the driving trajectories (plots) corresponding to the position information of the work vehicle 10 obtained during teaching driving (see FIG. 3) with approximate straight lines and approximate curves. The plots included in the second reference line Rb shown in FIG. 6 indicate the connection points between the partial straight lines (x1, x2) of the approximate straight line and the partial curves (y1, y2) of the approximate curve. For example, when connecting three consecutive plots with two straight lines, if the angle formed by the two straight lines is greater than or equal to a predetermined angle, the three points are approximated by one straight line, and if the angle formed by the two straight lines is less than the predetermined angle, the three points are approximated by one curve.

[0052] Next, the setting processing unit 212 sets a first reference line Ra based on the second reference line Rb. Specifically, the setting processing unit 212 converts the curve (turning path) included in the second reference line Rb into a straight line based on the turning angle. In the example shown in FIG. 6, the setting processing unit 212 converts the partial curve y1 (curve segment) into one or more partial straight lines based on the turning angles corresponding to the first partial straight line x1 and the first partial straight line x2. Hereinafter, a specific example of a method for converting a partial curve into a partial straight line will be described.

[0053] For example, as shown in FIG. 7A, when the turning angles θ in the first partial straight line x1 and the first partial straight line x2 are less than a first predetermined angle (for example, 3 degrees) (in other words, when the angle (180 degrees - θ) formed by the first partial straight line x1 and the first partial straight line x2 is 177 degrees or more), the setting processing unit 212 obtains the intersection point x0 of the extension line of the first partial straight line x1 and the extension line of the first partial straight line x2. Then, the setting processing unit 212 deletes the partial curve y1 and replaces it with the first partial straight line x1 and the first partial straight line x2 connected at the intersection point x0. That is, the setting processing unit 212 replaces the first partial straight line x1, the partial curve y1, and the first partial straight line x2 with the two extended first partial straight lines x1, x2.

[0054] For example, as shown in FIG. 7B, when the turning angle θ at the first partial straight line x1 and the first partial straight line x2 is equal to or greater than a first predetermined angle (e.g., 3 degrees) and less than a second predetermined angle (e.g., 6 degrees), the setting processing unit 212 replaces the partial curve y1 with a single complementary line (the first partial straight line x12). That is, the setting processing unit 212 replaces the first partial straight line x1, the partial curve y1, and the first partial straight line x2 with three first partial straight lines x1, x12, and x2.

[0055] For example, as shown in FIG. 7C, when the turning angle θ at the first partial straight line x1 and the first partial straight line x2 is equal to or greater than the second predetermined angle (e.g., 6 degrees), the setting processing unit 212 replaces the partial curve y1 with a plurality of complementary lines. Specifically, the setting processing unit 212 uses the value obtained by dividing the turning angle θ by the set angle as the number of complementary points, and arranges the calculated number of complementary points at equal intervals on the partial curve y1. In FIG. 7C, the setting processing unit 212 arranges two complementary points on the partial curve y1 and replaces the partial curve y1 with three first partial straight lines x121 to x123. The setting processing unit 212 replaces the first partial straight line x1, the partial curve y1, and the first partial straight line x2 with five first partial straight lines x1, x121, x122, x123, and x2.

[0056] The setting processing unit 212 converts each partial curve included in the second reference line Rb into a partial straight line by the method described above. Then, as shown in FIG. 6, the setting processing unit 212 sets a first reference line Ra composed of a plurality of straight lines (first partial straight lines) based on the second reference line Rb. In the first reference line Ra shown in FIG. 6, the partial curve y1 of the second reference line Rb is converted into the first partial straight lines x11 to x13, and the partial curve y2 of the second reference line Rb is converted into the first partial straight lines x21 to x23. The first reference line Ra is composed of eight partial straight lines.

[0057] As described above, the setting processing unit 212 sets the first reference line Ra based on the second reference line Rb including the partial curve generated based on a plurality of position information. Further, the setting processing unit 212 sets the second reference line Rb including a partial straight line and a partial curve based on a plurality of position information, converts the partial curve into one or a plurality of partial straight lines according to the angle (or turning angle) formed by the two partial straight lines, and connects the partial straight line included in the second reference line Rb and the partial straight line obtained by converting the partial curve included in the second reference line Rb to set the first reference line Ra. Further, the operation control unit 21 determines the number of the partial straight lines for converting the partial curve based on the angle (turning angle) formed by the two first partial straight lines.

[0058] The generation processing unit 213 generates a target route for automatically driving the work vehicle 10 in the field F. When the operator selects "Route Creation" (see FIG. 5) on the menu screen D1 and receives an instruction to generate a target route, the generation processing unit 213 executes the generation process of the target route. Specifically, the generation processing unit 213 generates a target route based on the first reference line Ra.

[0059] Here, a method of generating a target route by replicating (translating in parallel) the entire first reference line Ra can be considered, but the following problems occur with this method. Specifically, as shown in FIG. 8, when the entire first reference line Ra is translated in parallel by a distance corresponding to the working width W1 to generate a working route R1 (target route), the worked area B1 when working along the first reference line Ra and the worked area B2 when working along the working route R1 overlap (the overlapping area of the partial Bx), or a gap (the unworked area of the partial By) occurs between the worked areas B1 and B2.

[0060] In contrast, the generation processing unit 213 according to the present embodiment is configured to generate a target route by individually translating each of the plurality of first partial straight lines constituting the first reference line Ra by a predetermined distance and connecting each of the plurality of second partial straight lines corresponding to each of the plurality of first partial straight lines after the translation. According to the above configuration, as shown below, the above problem shown in FIG. 8 can be solved.

[0061] Specifically, as shown in FIG. 9, the generation processing unit 213 generates a second partial straight line x31 by translating the first partial straight line x1 of the first reference line Ra by the working width W1, generates a second partial straight line x32 by translating the first partial straight line x11 by the working width W1, generates a second partial straight line x33 by translating the first partial straight line x12 by the working width W1, generates a second partial straight line x34 by translating the first partial straight line x13 by the working width W1, generates a second partial straight line x35 by translating the first partial straight line x2 by the working width W1, generates a second partial straight line x36 by translating the first partial straight line x21 by the working width W1, generates a second partial straight line x37 by translating the first partial straight line x22 by the working width W1, and generates a second partial straight line x38 by translating the first partial straight line x23 by the working width W1. Then, the generation processing unit 213 connects the plurality of second partial straight lines x31 to x38 after translation to generate a working path R1 (target path).

[0062] Details of the procedure of the method for generating the target path will be described with reference to FIGS. 10A to 10C. FIG. 10A shows a first reference line Ra composed of four first partial straight lines xa1 to xa4. First, as shown in FIG. 10A, the generation processing unit 213 translates each of the first partial straight lines xa1 to Xa4 by the working width W1. Next, the generation processing unit 213 extends each of the translated straight lines xa11 to xa14. Next, as shown in FIG. 10B, the generation processing unit 213 obtains the intersection points p1 to p3 of the extended straight lines xa11 to xa14. Further, the generation processing unit 213 obtains the intersection point pa of the orthogonal line La that is orthogonal to the straight line L0 connecting the start point and the end point of the first reference line Ra and passes through the start point and the straight line xa11, and obtains the intersection point pb of the orthogonal line Lb that is orthogonal to the straight line L0 and passes through the end point and the straight line xa14. Then, as shown in FIG. 10C, the generation processing unit 213 generates a target path (working path R1) composed of a second partial straight line xb1 connecting the intersection points pa and p1, a second partial straight line xb2 connecting the intersection points p1 and p2, a second partial straight line xb3 connecting the intersection points p2 and p3, and a second partial straight line xb4 connecting the intersection points p3 and pb.

[0063] By generating the target path using the above method, the problems of overlap and gaps between the working widths described above (see Fig. 8) can be solved. Fig. 11 shows the working path R1 (target path) generated based on the first reference line Ra. As shown in Fig. 11, since the worked area B1 corresponding to the first reference line Ra and the worked area B2 corresponding to the working path R1 do not overlap and no gap is generated between the worked areas B1 and B2, the working accuracy in the turning operation can be improved.

[0064] When the generation processing unit 213 generates the target path of the work vehicle 10, it registers the target path in association with the field F. Note that the generation processing unit 213 can generate and register a plurality of target paths corresponding to the work content for one field F.

[0065] The output processing unit 214 outputs the path data of the target path to the work vehicle 10. For example, when the operator selects a desired target path on the operation screen and gives a work start instruction, the output processing unit 214 outputs the path data of the selected target path to the work vehicle 10.

[0066] When the path data of the target path generated on the operation terminal 20 is transferred to the work vehicle 10 and stored in the storage unit 12, the work vehicle 10 is configured to autonomously travel along the target path while detecting its current position by the positioning antenna 164. Note that the current position of the work vehicle 10 may usually coincide with the position of the positioning antenna 164.

[0067] When the work vehicle 10 satisfies a predetermined start condition and the work start button is pressed on the operation screen by the operator to give a work start instruction, the travel processing unit 111 starts automatic travel and starts the work by the work implement 14 (see Fig. 2). For example, the operation control unit 21 permits the automatic travel of the work vehicle 10 on the condition that the current position of the work vehicle 10 is within a predetermined distance from the travel start position and the vehicle azimuth is within a predetermined azimuth. Note that the start condition for permitting the automatic travel of the work vehicle 10 is not limited to the above condition.

[0068] The travel processing unit 111 of the work vehicle 10 automatically travels the work vehicle 10 from the travel start position to the travel end position according to the target route acquired from the operation terminal 20.

[0069] Note that the operation terminal 20 may be accessible via the communication network N1 to a website (agricultural support site) of an agricultural support service provided by a server (not shown). In this case, the operation terminal 20 can function as an operation terminal for the server when a browser program is executed by the operation control unit 21. And the server includes each of the above-described processing units and executes each process.

[0070] [Route generation process] Hereinafter, an example of the route generation process executed by the automatic driving system 1 will be described with reference to FIG. 12.

[0071] Note that the present invention can be regarded as an invention of a route generation method that executes one or more steps included in the route generation process. Also, one or more steps included in the route generation process described here may be appropriately omitted. Note that the execution order of each step in the route generation process may be different as long as the same operational effects are produced. Further, here, the case where the operation control unit 21 executes each step in the route generation process is taken as an example for explanation, but a route generation method in which one or more processors execute each step in the route generation process in a distributed manner is also considered as another embodiment.

[0072] In step S1, the operation control unit 21 determines whether to start field registration. For example, when an operator selects "field registration" on the menu screen D1 (see FIG. 5) displayed on the operation terminal 20, the operation control unit 21 determines to start field registration and shifts the process to step S2. The operation control unit 21 waits until a selection operation of "field registration" is received (S1: No).

[0073] In step S2, the operation control unit 21 acquires information on the travel locus of the work vehicle 10 by the operator's manual driving. For example, when the operator selects "field registration", the operator gets on the work vehicle 10 and drives (teaching driving) so as to make one round along the outer periphery of a predetermined area AR (see FIG. 3). While the work vehicle 10 is traveling, the operation control unit 21 acquires positioning information (position information of the current position of the work vehicle 10) measured by the positioning unit 16. In addition, when the operator raises and lowers the working machine 14 of the work vehicle 10 while manually driving, the operation control unit 21 may also acquire information on the position where the working machine 14 has been raised and lowered.

[0074] Next, in step S3, the operation control unit 21 registers the field. Specifically, when the teaching driving is completed, the operation control unit 21 registers the field based on the position information (measured points) of the travel locus. For example, as shown in FIG. 4, the operation control unit 21 obtains an approximate straight line connecting the travel locus (plot) traveled by the work vehicle 10, generates intersection points (complementary points a1 to a6) between the extension lines of adjacent approximate straight lines, and registers the area surrounded by the straight line connecting the generated complementary points a1 to a6 as the field F.

[0075] When the operation control unit 21 registers the field, it generates a path (target path) for automatically driving the work vehicle 10. Specifically, first, in step S4, the operation control unit 21 sets a second reference line Rb (see FIG. 6) including a partial curve based on the travel locus (plot). For example, the operation control unit 21 sets the second reference line Rb by connecting the travel locus corresponding to the position information of the work vehicle 10 obtained in the teaching driving (see FIG. 3) with an approximate straight line and an approximate curve.

[0076] Next, in step S5, the operation control unit 21 sets a first reference line Ra based on the second reference line Rb. Specifically, the operation control unit 21 converts the partial curve (turning path) included in the second reference line Rb into a partial straight line based on the turning angle, and sets a first reference line Ra composed of a plurality of partial straight lines (first partial straight lines). The operation control unit 21 converts a curve into one or a plurality of straight lines by the above-described method shown in FIGS. 7A to 7C, for example.

[0077] Next, in step S6, the operation control unit 21 individually translates each of the plurality of first partial straight lines included in the first reference line Ra by a predetermined distance. Specifically, as shown in FIG. 9, the operation control unit 21 individually translates the first partial straight lines x1, x11 to x13, x2, x21 to x23 included in the first reference line Ra by the working width W1.

[0078] Next, in step S7, the operation control unit 21 generates a target path based on the translated partial straight lines. Specifically, as shown in FIG. 9, the operation control unit 21 connects the second partial straight lines x31 to x38 obtained by translating the first partial straight lines x1, x11 to x13, x2, x21 to x23 by the working width W1 to generate a working path R1 (target path). Note that the operation control unit 21 generates the second partial straight lines x31 to x38 by translating the first partial straight lines x1, x11 to x13, x2, x21 to x23 and connecting the extension lines of the respective first partial straight lines. The operation control unit 21 generates a plurality of working paths R1 to Rn based on the first reference line Ra. The target path includes the plurality of working paths R1 to Rn. Note that the first reference line Ra may or may not be included in the working path.

[0079] Finally, in step S8, the operation control unit 21 registers the generated target path. Specifically, the operation control unit 21 registers the target path including the plurality of working paths in association with the farm field F. As described above, the operation control unit 21 executes the path generation process.

[0080] When the work vehicle 10 is automatically driven according to the generated target path, the operator gives a work start instruction on the operation screen of the operation terminal 20. Thereby, the vehicle control device 11 acquires the work start instruction from the operation terminal 20 and starts the automatic driving of the work vehicle 10.

[0081] As described above, the automatic driving system 1 according to the present embodiment generates a target path for automatically driving the work vehicle 10 in the farm field F (working area). Further, when generating the target path, the automatic driving system 1 sets a first reference line Ra serving as a reference, the first reference line Ra including a plurality of first partial straight lines, individually translates each of the plurality of first partial straight lines by a predetermined distance, and connects each of the plurality of second partial straight lines corresponding to each of the plurality of first partial straight lines after the parallel translation to generate the target path. For example, based on the position information indicating the traveling locus when the work vehicle 10 is driven in a teaching manner when registering the farm field, the automatic driving system 1 sets a second reference line Rb including a partial curve, and converts the partial curve of the second reference line Rb into a partial straight line (see FIGS. 7A to 7C) to set the first reference line Ra composed of a plurality of partial straight lines. Then, the automatic driving system 1 individually translates each of the plurality of partial straight lines (first partial straight lines) included in the first reference line Ra by a predetermined distance, and connects each of the plurality of second partial straight lines corresponding to each of the plurality of first partial straight lines after the parallel translation to generate the target path (see FIG. 6).

[0082] According to the above configuration, it is possible to generate a target path including a turning path capable of performing work while turning. Further, in adjacent work paths, since the worked areas do not overlap and no gaps (see FIG. 8) are generated between the worked areas, the work accuracy in the turning operation can be improved (see FIG. 11).

[0083] [Other Embodiments] The present invention is not limited to the above-described embodiments. Other embodiments of the present invention will be described below.

[0084] In the above-described embodiment, the operation control unit 21 sets the second reference line Rb including a partial curve based on the position information of the traveling locus acquired at the time of field registration, and converts the partial curve of the second reference line Rb into a partial straight line to set the first reference line Ra. As another embodiment, the operation control unit 21 may omit the setting process of the second reference line Rb. Specifically, the operation control unit 21 may set the first reference line Ra composed of a plurality of partial straight lines (first partial straight lines) based on the position information of the traveling locus acquired at the time of field registration. For example, as shown in FIG. 16, the operation control unit 21 connects each measurement point with a straight line, and when the angle d formed between two adjacent straight lines is equal to or greater than a predetermined angle, replaces the two straight lines with one straight line, and when the angle d is less than the predetermined angle, leaves the two straight lines, and repeats this process to set the first reference line Ra. That is, the operation control unit 21 may set the first reference line Ra by integrating or dividing the partial straight lines according to the orientation of adjacent partial straight lines in the plurality of partial straight lines (first partial straight lines) constituting the traveling locus of the work vehicle 10 acquired by the manual traveling operation of the user when registering the work area.

[0085] As another embodiment of setting the first reference line Ra, the operation control unit 21 may set the first reference line Ra based on a registration reference line connecting arbitrary points registered by the operator. For example, the operator performs a registration operation at any plurality of positions while manually driving the work vehicle 10 in the field F. When the operation control unit 21 sets a registration reference line connecting the registered plurality of positions, the operation control unit 21 sets the first reference line Ra based on the registration reference line. Thereby, for example, when the operator registers points A, B, and C, the operation control unit 21 can generate a target path corresponding to the turning operation of the turning portion corresponding to the angle formed by the two straight lines by setting the first reference line Ra composed of the straight line connecting points A and B and the straight line connecting points B and C.

[0086] In the above-described embodiment, the first reference line Ra is composed of a plurality of straight lines (first partial straight lines). However, as another embodiment, the first reference line Ra may be composed of a straight line and a curve. When the first reference line Ra includes a curve, the operation control unit 21 individually translates the straight line (first partial straight line) and the curve by a predetermined distance, and executes a process of correcting the radius of curvature (turning radius) for the curve. For example, when translating a curve that is convex to the right and included in the first reference line Ra to the right, the operation control unit 21 corrects the radius of curvature of the curve after translation to a value larger than the radius of curvature of the curve of the first reference line Ra. On the other hand, when translating a curve that is convex to the left and included in the first reference line Ra to the right, the operation control unit 21 corrects the radius of curvature of the curve after translation to a value smaller than the radius of curvature of the curve of the first reference line Ra. Thus, the first reference line Ra may be configured to include a curve.

[0087] By the way, when generating a target path based on the first reference line Ra in each of the above-described embodiments, for a turning path included in the target path, there may be a case where the turning radius becomes less than the minimum turning radius at which the work vehicle 10 can turn. FIG. 13A schematically shows an adjacent first reference line Ra and a work path R1. Here, when the turning radius of the turning path included in the first reference line Ra is the minimum turning radius Rmin, the turning radius Rn of the turning path of the work path R1 may become a value smaller than the minimum turning radius Rmin (Rn < Rmin). In this case, a problem occurs in that the work vehicle 10 cannot turn and travel on the work path R1.

[0088] Therefore, in order to solve the above problems, when the operation control unit 21 connects two adjacent partial straight lines (second partial straight lines), if the turning radius when turning along these two partial straight lines is less than the minimum turning radius at which the work vehicle 10 can turn, the operation control unit 21 may move the turning center corresponding to these two partial straight lines. Specifically, as shown in FIG. 13B, for the turning path of the work path R1, the operation control unit 21 sets the turning radius Rn to the minimum turning radius Rmin (Rn = Rmin) and moves the turning center from the position C1 to the position C2. Note that the operation control unit 21 may set the turning center at a position where the turning radius Rn is equal to or greater than the minimum turning radius Rmin. In this way, when the turning radius Rn of the work vehicle 10 is less than the minimum turning radius Rmin, the operation control unit 21 executes a process of correcting the turning path. Hereinafter, a specific example of the turning path correction method will be described.

[0089] FIG. 14A shows the first reference line Ra, the work path R1 before correction, and the connection points of the partial straight lines in the turning portions of the respective paths. First, the operation control unit 21 identifies the partial straight lines for which correction of the turning path is necessary.

[0090] For example, in the method shown in FIGS. 7A to 7C (method of converting a curve into a straight line), the operation control unit 21 creates complementary lines in a number obtained by dividing the turning angle by a first predetermined angle (for example, 3 degrees). In this case, the turning angle θ between the two straight lines is at most 4.5 degrees. For example, when there are two complementary lines and the remainder of the divided value is infinitely close to 3 degrees, the maximum turning angle θ is (3 + 2.999··· / 2) degrees. Therefore, when the turning angle θ between the two straight lines is 4.5 degrees or more, the operation control unit 21 determines that correction is necessary for the turning path composed of the two straight lines.

[0091] As another method, for example, by converting to a straight line as shown in FIGS. 7A to 7C, the end points of the straight line of the turning portion are considered to exist on the turning circle Cb as shown in FIG. 15A. Therefore, a circle Ca with a minimum turning radius Rmin is created, and when the following straight line exists inside the circle Ca, it can be determined that the circle Cb is smaller than the circle Ca with the minimum turning radius Rmin. FIGS. 15B and 15C show schematic diagrams when a straight line exists on the circle Ca with the minimum turning radius Rmin. When the angular deviation between the two straight lines is less than 3 degrees, the operation control unit 21 calculates the azimuth deviation between the straight lines as θ (see FIG. 15B), and when the angular deviation between the two straight lines is 3 degrees or more, the operation control unit 21 calculates the azimuth deviation between the straight lines as 2θ (see FIG. 15C). Specifically, the operation control unit 21 obtains the minimum length L of the straight line of the turning portion by the following formula. L = 2Rmin·cos(90 - |θ|) L = 2Rmin·sin(|θ|)

[0092] Thereby, when the length S of the target straight line (partial straight line of the turning path) is smaller than the minimum length L (S < L), the operation control unit 21 determines that correction is necessary for the turning path composed of the straight line.

[0093] In the example shown in FIG. 14A, the operation control unit 21 specifies the partial straight line on the circle Cb with a turning radius Rn smaller than the minimum turning radius Rmin as the partial straight line that needs to be corrected. When the operation control unit 21 specifies the partial straight line that needs to be corrected for the turning path by the above method, subsequently, a circle Cc with a minimum turning radius Rmin that is inscribed in the two partial straight lines before and after the turning path is obtained (see FIG. 14B). Then, the operation control unit 21 sets the turning start point p10 and the turning end point p20 on the obtained circle Cc, and generates a turning path from the turning start point p10 to the turning end point p20. Specifically, the operation control unit 21 specifies the circle Cc with the minimum turning radius Rmin among the circles inscribed in each of the two partial straight lines, and sets the connection points (turning start point p10 and turning end point p20) of the two partial straight lines on the arc of the specified circle Cc. Note that the operation control unit 21 generates the turning path as a plurality of partial straight lines.

[0094] In this way, when the turning path included in the generated target path has a turning radius less than the minimum turning radius, the operation control unit 21 corrects the turning radius corresponding to the turning path. Thereby, the problem that the work vehicle 10 cannot turn and travel on the work path R1 can be solved.

[0095] Note that when the turning radius is corrected, a gap may occur between the worked areas corresponding to adjacent turning paths. Therefore, the operation control unit 21 may notify the operator that a gap has occurred between the worked areas, or may inquire of the operator whether to permit the occurrence of the gap.

[0096] [Example of generation of reference curve (first reference line Ra)] An example of the procedure for generating the first reference line Ra will be described. Here, an example of the procedure for generating the first reference line Ra will be described based on the measurement points (measurement points) obtained by teaching travel.

[0097] FIG. 17A shows a work area registration screen D2 for registering a work area. For example, after the registration of the field based on the measurement points is completed, when the operator selects "Work area registration" on the menu screen D1 (see FIG. 5) and selects the target field, the operation control unit 21 displays the work area registration screen D2 shown in FIG. 17A. On the work area registration screen D2, the operator performs an operation to set the work area. For example, the operator selects the vertices that are the corner portions of the outer shape side of the work area among the measurement points. Note that the operator may select the measurement points located at the corners, or may select the outside of the measurement points located at the corners. When the operator selects the outside of the measurement points, the operation control unit 21 sets complementary points that are the end points of the outer shape side. FIG. 17B shows a state where the operator has selected four points on the work area registration screen D2.

[0098] The operation control unit 21 sets and displays a straight line (side) connecting each point selected by the operator. Also, on the work area registration screen D2 shown in FIG. 17B, the operation control unit 21 accepts an operation of selecting a side for performing curve work among the set sides. When the operator has a side for which curve work is desired among the sides, the operator selects that side (taps the side on the screen (see FIG. 17B)), and when there is no side for which curve work is desired (when performing straight line work for the entire area), the operator selects "Next". When the operator selects the right side for which curve work is desired (see FIG. 17B), the operation control unit 21 generates a running trajectory (reference curve) of the curve based on the measurement points corresponding to the right side (measurement points between the right end point of the upper side and the right end point of the lower side).

[0099] Here, a method for discriminating measurement points (measurement points that become the end points of the curve) corresponding to the selected side will be described. For example, the operation control unit 21 identifies a point P corresponding to the end point of the selected side through the following procedure, and generates a curve based on the measurement points between the points P.

[0100] (Step 1) In Step 1, as shown in FIG. 18A, the operation control unit 21 determines whether the vertex (selected point) of the work area is included in the running trajectory (measurement point). When the vertex of the work area is included in the running trajectory, the operation control unit 21 sets point P at the position of the vertex, and when the vertex of the work area is not included in the running trajectory, it proceeds to Step 2.

[0101] (Step 2) In Step 2, as shown in FIG. 18B, the operation control unit 21 determines whether the running trajectory is included within a range of a predetermined distance X (m) from the vertex (complementary point) of the work area. When the running trajectory is included within the range of the predetermined distance X from the vertex of the work area, the operation control unit 21 deletes the running trajectory within the range and sets point P at the deleted position. When the running trajectory is not included within the range of the predetermined distance X from the vertex of the work area, the operation control unit 21 proceeds to Step 3.

[0102] (Step 3) In Step 3, as shown in FIG. 18C, when it is a vertex between the sides of the curve, the operation control unit 21 sets the closest point as point P within the range of (the minimum length from the vertex to the side) / 2 and within the range of (the threshold value) / 2 from the bisector of the side. Note that the threshold value used for the omission determination of the measurement points is set to 0.1 m, for example. The operation control unit 21 omits the point if the distance between the measurement points is equal to or less than the threshold value. If no point satisfying the above conditions is found, the operation control unit 21 sets the starting point as point P because it is assumed that the starting point and the ending point are far apart.

[0103] Also in Step 3, as shown in FIG. 18D, when it is a vertex between the side of the curve and the side of the straight line, the operation control unit 21 sets the first found point within the range of (the threshold value) / 2 from the straight side as point P. According to this method, it is possible to correspond to the running locus of the curve shown in FIG. 19.

[0104] As described above, the operation control unit 21 specifies point P (both end points) and generates a curved path for one side based on the running locus (measurement points) between point P. When the operation control unit 21 generates the curved path, as shown in FIG. 20, it replaces the selected side (see FIG. 17B) with a curve and displays it.

[0105] Note that the operation control unit 21 can generate one curved path based on the partial straight line connecting a plurality of measurement points located between point P1 by the method shown in the above-described embodiment (FIGS. 6 to 16). That is, the curved path is generated by connecting straight paths of a predetermined length. Further, the operation control unit 21 may set the curved path as the first reference line Ra.

[0106] Next, another method for generating the first reference line Ra will be described. Specifically, the operation control unit 21 generates the first reference line Ra based on at least one of the conditions of the path length, the azimuth deviation between adjacent paths, and the deviation (distance) between the measurement point and the path. For example, the operation control unit 21 generates a partial straight line such that the path length is equal to or greater than a first predetermined length (e.g., 1 m) (the first condition). Also, the operation control unit 21 generates a partial straight line such that the path length is less than a second predetermined length (e.g., 5 m) (the second condition). Further, the operation control unit 21 generates a partial straight line such that the azimuth deviation between adjacent paths is less than 3 degrees (the angle formed by adjacent paths is 177 degrees or more) (the third condition). Additionally, the operation control unit 21 generates a partial straight line such that the deviation between the measurement point and the path is less than 10 cm (the fourth condition).

[0107] The operation control unit 21 may generate the first reference line Ra by setting the priorities of the above-described first to fourth conditions. For example, the operation control unit 21 may set the first condition as the first priority and the second to fourth conditions as the second priority.

[0108] FIG. 21A shows an example of a partial straight line that satisfies the first condition, the second condition, and the third condition. The θ in FIG. 21A represents the azimuth deviation between adjacent paths. FIG. 21B shows an example of a partial straight line that satisfies the first condition, the second condition, and the fourth condition. L1 to L4 in FIG. 21B each represent the deviation between the measurement point and the path.

[0109] Note that when priorities are set for the conditions, there is a possibility that a path that does not satisfy the condition with a lower priority may be generated. In order to prevent the generation of such an unexpected path, the operation control unit 21 may set an error determination condition that regards an unacceptable path as an error. For example, as the error determination condition, "the azimuth deviation between adjacent paths is 10 degrees or more (the angle formed by adjacent paths is less than 170 degrees)", "the deviation between the measurement point and the path is 30 cm or more", etc. are set. When the operation control unit 21 determines that an error occurs by satisfying the error determination condition, it interrupts the generation of the curved path and displays a path generation error screen (not shown).

[0110] In addition, on the screen for path generation error, when the operator permits a path determined as an error, the operation control unit 21 may set the path as a curved path (first reference line Ra).

[0111] In addition, on the screen for path generation error, when the operator gives an instruction to correct the path, the operation control unit 21 may correct the path to a path that does not satisfy the error determination condition and regenerate the curved path. Note that the operator may be able to set, on a preset screen in advance, whether to execute the path correction process when a path generation error occurs.

[0112] In addition, when the operation control unit 21 corrects a path, it may display the path before correction and the path after correction side by side to receive a selection operation from the operator, and set the selected path as the curved path (first reference line Ra).

[0113] [Extension of the first reference line Ra] The operation control unit 21 may extend the generated first reference line Ra (curved path). Specifically, the operation control unit 21 generates a straight line (extension line) obtained by extending the first straight path (partial straight line) and the last straight path (partial straight line) that constitute the first reference line Ra to the outside. The length of the extension line is set to, for example, 1 km. In addition, the operation control unit 21 may display the extended portion (extension line) in an identifiable manner. By extending the path, for example, it becomes possible to automatically drive the work vehicle 10 to the field boundary (ridge edge).

[0114] FIG. 22 shows an example of a path obtained by extending the first reference line Ra. For example, in the curved path (first reference line Ra) from the start point Ps (the start point of the first straight path Rs that constitutes the curved path (first reference line Ra)) to the end point Pg (the end point of the last straight path Rg that constitutes the curved path), the operation control unit 21 sets an extension line Rs1 obtained by extending the first straight path Rs and an extension line Rg1 obtained by extending the last straight path Rg.

[0115] Also, as shown in FIG. 23, the operation control unit 21 generates a work path R1 by replicating the generated curve path (first reference line Ra) in the left - right direction. At this time, the extended path (extension line) may not be the object of replication. Specifically, the operation control unit 21 replicates by parallel - moving each straight - line path (partial straight line) constituting the curve path at equal intervals in the perpendicular direction in the same manner as the method shown in FIGS. 10A to 10C. Note that the distance of parallel movement is set based on the setting information of the work machine 14 (for example, work width, overlap width, etc.). After replicating (parallel - moving) the curve path, the operation control unit 21 may execute the above - mentioned path extension process (see FIG. 22) for each replicated curve path. Note that the number of paths to be replicated may be settable by the operator. For example, when the operator designates 10 paths, the operation control unit 21 replicates a total of 20 curve paths, 10 on the left side and 10 on the right side of the first reference line Ra.

[0116] Also, as shown in FIG. 24A, the operation control unit 21 may extend the work path R1 replicated (generated) based on the first reference line Ra and display it on the operation screen. Each work path R1 is composed of a plurality of straight - line paths (partial straight lines), but the operation control unit 21 displays it as one curve path on the operation screen. Also, the operation control unit 21 may display the extension line so that it can be identified, may omit the display of the extension line, or may switch the display / non - display of the extension line according to the operator's operation. In FIG. 24A, the extension line is represented by a dotted line.

[0117] Also, the operation control unit 21 may search (path - search) for a work path R1 that enables the start of automatic driving and display the searched work path R1 so that it can be identified. Specifically, the operation control unit 21 searches for one or a plurality of work paths R1 included in a range in a predetermined direction from the current position of the work vehicle 10 and highlights the work paths R1 included in the range. FIG. 24B shows a state where three work paths R1 included in the range are highlighted on the operation screen.

[0118] In addition, as shown in FIG. 24C, when one work path R1 that is the target of the automatic driving path is determined, the operation control unit 21 may highlight the work path R1. Further, the operation control unit 21 may highlight the one work path R1 while the vehicle is automatically driving.

[0119] [Display method of work path R1] The operation control unit 21 may display the work path R1 (target path) on the operation screen in accordance with the outer shape side of the farm field F. For example, as shown in FIG. 25A, the operation control unit 21 may display each work path R1 as a single curved path and may be configured to display each work path R1 only inside the farm field F and not outside the farm field F. Specifically, as shown in FIG. 25A, the operation control unit 21 does not display the start end side and the end side portions located outside the farm field F among each work path R1 (see FIG. 24A) including the extension line, and displays only the portion located inside the farm field F. Note that the operation control unit 21 may display the straight path extended outside the farm field F (the path indicated by the dotted line in FIG. 25A).

[0120] Further, as shown in FIG. 25B, in the headland area, the operation control unit 21 may display a predetermined number of work paths R1 and may display some of the work paths R1 outside the farm field F. For example, in the headland area, the operation control unit 21 may display eight work paths R1, display six of the work paths R1 inside the farm field F, and display the remaining two work paths R1 outside the farm field F. Note that the operation control unit 21 may display the number of work paths R1 set by the operator inside and outside the farm field F.

[0121] Also, as shown in FIG. 25C, the operation control unit 21 may be able to lock (fix to the target path for starting automatic driving) the curved side (first reference line Ra) among the outer side edges of the farm field F. FIG. 25C shows a state where the curved side is locked. For example, when the operator taps the curved side on the operation screen, the operation control unit 21 locks the curved side. Also, for example, when the operator taps the lock icon on the operation screen while the work vehicle 10 is facing the same or a similar direction as the direction of the work path R1 of the curve, the operation control unit 21 may lock the curved side. As another embodiment, when none of the sides are locked, the operation control unit 21 may display (highlight) the path of the side close to the current orientation of the work vehicle 10 in an identifiable manner.

[0122] In each of the above-described embodiments, the automatic driving system 1 corresponds to the path generation system according to the present invention. However, the path generation system according to the present invention may be configured by the operation terminal 20 alone, may be configured by combining the work vehicle 10 and the operation terminal 20, or may be configured by a server (not shown) alone.

[0123] [Supplementary Note of the Invention] Hereinafter, the outline of the invention extracted from each of the above-described embodiments will be appended. Note that each configuration and each processing function described in the following supplementary note can be arbitrarily selected and combined.

[0124] [Supplementary Note 1] A path generation method for generating a target path for automatically driving a work vehicle in a work area, setting a first reference line, which is a reference for generating the target path, and includes a plurality of first partial straight lines; individually translating each of the plurality of first partial straight lines by a predetermined distance; connecting each of the plurality of second partial straight lines corresponding to each of the plurality of first partial straight lines after the parallel translation to generate the target path; A path generation method for executing the above.

[0125] [Supplementary Note 2] Based on the position information indicating the travel locus of the work vehicle obtained by the manual driving operation of the user when registering the work area, the first reference line is set. The route generation method according to Supplementary Note 1.

[0126] <Supplementary Note 3> Each of the plurality of first partial straight lines is translated in parallel by the predetermined distance according to the working width of the work vehicle. The route generation method according to Supplementary Note 1 or 2.

[0127] <Supplementary Note 4> When two adjacent second partial straight lines are connected, if the turning radius when turning along these two second partial straight lines is less than the minimum turning radius at which the work vehicle can turn, the turning center corresponding to these two second partial straight lines is moved. The route generation method according to any one of Supplementary Notes 1 to 3.

[0128] <Supplementary Note 5> The turning center is set at a position where the turning radius of the work vehicle is greater than or equal to the minimum turning radius. The route generation method according to Supplementary Note 4.

[0129] <Supplementary Note 6> Among the circles inscribed in each of the two second partial straight lines, the circle with the minimum turning radius is specified. On the arc of the specified circle, the connection point of the two second partial straight lines is set. The route generation method according to Supplementary Note 4 or 5.

[0130] <Supplementary Note 7> Based on the position information indicating the travel locus of the work vehicle obtained by the manual driving operation of the user when registering the work area, a second reference line including a partial curve is set, and the first reference line is set based on the second reference line. The route generation method according to any one of Supplementary Notes 1 to 6.

[0131] <Supplementary Note 8> Based on the plurality of position information, set the second reference line including partial straight lines and partial curves, Convert the partial curve disposed between the two partial straight lines into one or more partial straight lines according to the angle formed by the two partial straight lines, and set the first reference line by connecting the partial straight line included in the second reference line and the partial straight line obtained by converting the partial curve, The path generation method according to Supplementary Note 7.

[0132] <Supplementary Note 9> Based on the angle formed by the two partial straight lines, determine the number of partial straight lines for converting the partial curve, The path generation method according to Supplementary Note 8.

[0133] <Supplementary Note 10> Set the first reference line by integrating or dividing the partial straight line according to the orientation of adjacent partial straight lines in the plurality of partial straight lines constituting the traveling locus of the work vehicle obtained by the manual traveling operation of the user when registering the work area, The path generation method according to any one of Supplementary Notes 1 to 6.

[0134] <Supplementary Note 11> A path generation program for generating a target path for automatically driving a work vehicle in a work area, A first reference line serving as a reference when generating the target path, setting a first reference line including a plurality of first partial straight lines, Individually translating each of the plurality of first partial straight lines by a predetermined distance, Generating the target path by connecting each of the plurality of second partial straight lines corresponding to each of the plurality of first partial straight lines after the parallel translation, A path generation program for causing one or more processors to execute.

[0135] <Supplementary Note 12> A path generation system for generating a target path for automatically driving a work vehicle in a work area, A setting processing unit that sets a first reference line serving as a reference when generating the target path, the first reference line including a plurality of first partial straight lines. A generation processing unit that individually translates each of the plurality of first partial straight lines by a predetermined distance and connects each of the plurality of second partial straight lines corresponding to each of the plurality of first partial straight lines after the translation to generate the target path. A path generation system comprising the above.

Explanation of Signs

[0136] 1: Autonomous driving system 10: Work vehicle 11: Vehicle control device 14: Working machine 16: Positioning unit 20: Operation terminal 21: Operation control unit 111: Travel processing unit 211: Registration processing unit 212: Setting processing unit 213: Generation processing unit 214: Output processing unit F: Field (working area) R1: Working path (target path) Ra: First reference line Rb: Second reference line Rmin: Minimum turning radius Rn: Turning radius

Claims

1. A path generation method for generating a target path for automatically driving a work vehicle in a work area, comprising: setting a first reference line serving as a reference when generating the target path, the first reference line including a plurality of first partial straight lines; individually translating each of the plurality of first partial straight lines by a predetermined distance; connecting each of a plurality of second partial straight lines corresponding to each of the plurality of first partial straight lines after translation to generate the target path; A path generation method for executing the above.

2. The path generation method according to claim 1, wherein the first reference line is set based on position information indicating a travel locus of the work vehicle acquired by a manual driving operation of a user when registering the work area. The path generation method according to claim 1.

3. The path generation method according to claim 1, wherein each of the plurality of first partial straight lines is translated by the predetermined distance according to a work width of the work vehicle. The path generation method according to claim 1.

4. The path generation method according to claim 1, wherein when connecting two adjacent second partial straight lines, if a turning radius when turning along the two second partial straight lines is less than a minimum turning radius that the work vehicle can turn, a turning center corresponding to the two second partial straight lines is moved. The path generation method according to claim 1.

5. The path generation method according to claim 4, wherein the turning center is set at a position where a turning radius of the work vehicle is greater than or equal to the minimum turning radius. The path generation method according to claim 4.

6. Among the circles inscribed in each of the two second partial straight lines, a circle with the minimum turning radius is specified; A connection point of the two second partial straight lines is set on an arc of the specified circle. The path generation method according to claim 4.

7. The path generation method according to any one of claims 1 to 5, wherein a second reference line including a partial curve is set based on position information indicating a travel locus of the work vehicle acquired by a manual driving operation of a user when registering the work area, and the first reference line is set based on the second reference line. The path generation method according to any one of claims 1 to 5.

8. Based on the plurality of position information, a second reference line including a partial straight line and a partial curve is set; The partial curve arranged between the two partial straight lines is converted into one or a plurality of partial straight lines according to an angle formed by the two partial straight lines, and the first reference line is set by connecting the partial straight lines included in the second reference line and the partial straight lines obtained by converting the partial curve. The path generation method according to claim 7.

9. Determining the number of the partial straight lines for converting the partial curve based on the angle formed by the two partial straight lines. The path generation method according to claim 8.

10. When registering the work area, setting the first reference line by integrating or dividing the partial straight lines according to the orientation of adjacent partial straight lines among the plurality of partial straight lines constituting the travel locus of the work vehicle obtained by the manual travel operation of the user. The path generation method according to any one of claims 1 to 5.

11. A path generation program for generating a target path for automatically driving a work vehicle in a work area, A first reference line that serves as a reference when generating the target path, setting a first reference line including a plurality of first partial straight lines; Individually translating each of the plurality of first partial straight lines by a predetermined distance; Connecting each of the plurality of second partial straight lines corresponding to each of the plurality of first partial straight lines after the parallel translation to generate the target path; A path generation program for causing one or more processors to execute.

12. A path generation system for generating a target path for automatically driving a work vehicle in a work area, A first reference line that serves as a reference when generating the target path, a setting processing unit for setting a first reference line including a plurality of first partial straight lines; A generation processing unit that individually translates each of the plurality of first partial straight lines by a predetermined distance and connects each of the plurality of second partial straight lines corresponding to each of the plurality of first partial straight lines after the parallel translation to generate the target path; A path generation system comprising the above.

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