Control system for work vehicles

Abstract

To enhance work efficiency of a work vehicle by streamlining transfer thereof to a work starting point while avoiding a no-entry zone.SOLUTION: A work vehicle control system according to an embodiment comprises a control section which controls a traveling vehicle body, enabling a work vehicle to perform work while autonomously traveling along a work route. The control section: sets a turning radius of the traveling vehicle body while traveling and no-entry and no-deviation zones in an agricultural field; determines whether each vertex of the no-entry and no-deviation zones is a convex vertex or a concave vertex; plans a travel route of the traveling vehicle body from a current position to a work start point; adjusts the travel route entering the no-entry zone to follow a detour circle that passes through a convex vertex of the no-entry zone if the initially planned route intersects the no-entry zone; and modifies the travel route to follow a detour circle that passes through a concave vertex of the no-deviation zone if the initially planned route deviates from the no-deviation zone. Additionally, the detour circle is not configured to pass through the concave vertex of the no-entry zone and the convex vertex of the no-deviation zone.SELECTED DRAWING: Figure 10

Description

Technical Field

[0001] The present invention relates to a control system for a work vehicle.

Background Art

[0002] Conventionally, in a work vehicle such as an agricultural tractor capable of autonomous driving, when setting a work route for the work vehicle to perform autonomous driving, a candidate specifying area is set by a specifying unit that specifies an autonomous driving candidate route on which the work vehicle can start autonomous driving, and a work route included in the candidate specifying area can be specified as an autonomous driving candidate route (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] However, in the conventional technology as described above, when the position where the work vehicle starts autonomous driving (the position where work starts, hereinafter referred to as the work start point) is predetermined, an appropriate movement route to the work start point cannot be generated, so the efficiency of moving to the work start point cannot be improved. Further, even if there is an area that is not desired to enter (a prohibited entry area) when moving to the work start point, it is not possible to set an efficient movement route while bypassing the prohibited entry area. That is, there is room for further improvement in the conventional technology as described above in terms of improving work efficiency.

[0005] The present invention has been made in view of the above, and an object thereof is to provide a control system for a work vehicle that can improve the efficiency of moving to a work start point while bypassing a prohibited entry area and can improve work efficiency. [Means for solving the problem]

[0006] To solve the above-mentioned problems and achieve the objective, the control system for a work vehicle according to the embodiment comprises a vehicle body capable of traveling within a field, a positioning device for acquiring the vehicle body's own position, an azimuth angle acquisition means for acquiring the azimuth angle of the vehicle body, and a control unit for generating a work path including a work start point within the field and controlling the vehicle body to perform work while autonomously traveling along the generated work path. The control unit pre-sets the turning radius of the vehicle body when it moves within the field and an entry prohibition area that prohibits the vehicle body from entering as the inner area of ​​a closed polygon within the field, and sets a deviation prohibition area in the outer area of ​​the entry prohibition area. The aforementioned deviation prevention area is an area that prohibits the vehicle from deviating outside the closed polygon. The system is characterized by determining whether each vertex of the no-entry zone is a convex or concave vertex, determining whether each vertex of the no-deviation zone is a convex or concave vertex, setting a movement path from the vehicle's own position to the work start point, modifying the movement path that enters the no-entry zone to pass through a detour circle set at the convex vertex of the no-entry zone if the movement path deviates from the no-deviation zone, and modifying the movement path to pass through a detour circle set at the concave vertex of the no-deviation zone, with the detour circles not set at the concave vertex of the no-entry zone or the convex vertex of the no-deviation zone. [Effects of the Invention]

[0007] According to the work vehicle of this embodiment, it is possible to improve the efficiency of movement to the work starting point while bypassing restricted areas, thereby improving work efficiency. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a schematic left side view showing a work vehicle according to an embodiment. [Figure 2] Figure 2 is a block diagram showing the control system for a work vehicle according to an embodiment. [Figure 3] Figure 3 is an explanatory diagram (part 1) of autonomous driving in a field. [Figure 4] Figure 4 is an explanatory diagram (part 2) of autonomous driving in a field. [Figure 5] Figure 5 is a flowchart (part 1) showing the process of setting the travel route. [Figure 6] Figure 6 is a flowchart (part 2) showing the process of setting the travel route. [Figure 7] Figure 7 is an explanatory diagram of the travel path patterns. [Figure 8] Figure 8 shows (a) an explanatory diagram of a route pattern of left turn - right turn - left turn, and (b) an explanatory diagram of a route pattern of right turn - left turn - right turn. [Figure 9] Figure 9 is an explanatory diagram of a travel route that bypasses no-entry zones and no-deviation zones. [Figure 10] Figure 10 is an explanatory diagram (part 1) for setting up detour routes in restricted areas. [Figure 11] Figure 11 is an explanatory diagram (part 2) for setting up detour routes for restricted areas. [Figure 12] Figure 12 is an explanatory diagram (part 1) for setting detour routes in the no-deviation zone. [Figure 13] Figure 13 is an explanatory diagram (part 2) for setting detour routes in the no-deviation zone. [Modes for carrying out the invention]

[0009] Hereinafter, embodiments of the control system for work vehicles disclosed in this application will be described in detail with reference to the attached drawings. However, this invention is not limited to the embodiments described below.

[0010] <Overview of the work vehicle (tractor)> First, an overview of the work vehicle 1 according to the embodiment will be described with reference to Figure 1. Figure 1 is a schematic left side view showing the work vehicle 1 according to the embodiment. In the following description, a tractor will be used as an example of the work vehicle 1. Furthermore, the tractor 1, which is the work vehicle, is an agricultural tractor that performs farm work in the field while moving under its own power.

[0011] In addition, the tractor 1, which is a work vehicle, not only enables an operator (also referred to as a worker) to board and perform predetermined work while traveling in the field, but also executes predetermined work while autonomously traveling in the field by controlling each part by a control system centered around a control unit 200 (see FIG. 2) described later.

[0012] In the following description, the front-rear direction is the traveling direction when the tractor 1 is moving straight, and the front side in the traveling direction is defined as "front" and the rear side as "rear". The traveling direction of the tractor 1 is the direction from the driver's seat 8 described later to the steering wheel 9 when the tractor 1 is moving straight.

[0013] Also, the left-right direction is a direction that is horizontally orthogonal to the front-rear direction. Hereinafter, the left and right are defined toward the "front" side. That is, with the operator sitting on the driver's seat 8 and facing forward, the left hand side is "left" and the right hand side is "right". The up-down direction is the vertical direction. The front-rear direction, the left-right direction, and the up-down direction are three-dimensionally orthogonal to each other. In the following description, the tractor 1 or the traveling vehicle body 2 may be referred to as the "airframe" in some cases.

[0014] As shown in FIG. 1, the tractor 1 includes a traveling vehicle body 2 and a work implement 6. The traveling vehicle body 2 is capable of traveling in the field and includes front wheels 3 and rear wheels 4. The front wheels 3 are a pair of left and right steering wheels (steering wheels). The rear wheels 4 are a pair of left and right driving wheels (drive wheels). Note that the traveling vehicle body 2 may be provided with a crawler device instead of the wheels (at least any one of the front wheels 3 and the rear wheels 4). In this case, the traveling crawler is the drive wheel.

[0015] The rotational power generated by the engine E, which is a drive source housed in the bonnet 5, is appropriately decelerated and transmitted to the rear wheels 4, which are drive wheels, by a transmission 121 (see FIG. 2) provided in a power transmission device (transmission case) 12. The rear wheels 4 are driven by the rotational power transmitted from the engine E. The transmission 121 switches the rotational power transmitted from the engine E to any one of a plurality (for example, 1st speed to 8th speed) of gear positions.

[0016] The traveling vehicle body 2 is configured such that the power generated by the engine E and decelerated by the transmission 121 can also be transmitted to the front wheels 3 via the 4WD clutch. In this case, when the 4WD clutch transmits power, the four wheels of the front wheels 3 and the rear wheels 4 are driven by the power transmitted from the engine E. Also, when the 4WD clutch blocks the transmission of power, only the two rear wheels 4 are driven by the power transmitted from the engine E. Thus, the traveling vehicle body 2 is configured to be able to switch between two-wheel drive (2WD) and four-wheel drive (4WD).

[0017] An implement 6 for working in the field is connected to the rear part of the traveling vehicle body 2, and a PTO device 7 having a PTO (Power take-off) shaft 71 for transmitting the power for driving the implement 6 is provided. A driver's seat 8 on which an operator sits when operating the tractor 1 is provided at the center of the traveling vehicle body 2.

[0018] A steering wheel 9, which is a steering handle for the front wheels 3, is provided in front of the driver's seat 8. Note that the steering wheel 9 and the drive unit for driving the steering wheel, etc. constitute a steering device 122 (see FIG. 2). The steering wheel 9 is provided at the upper end of the handle post 10. Below the handle post 10 and near the feet of the operator when the operator is sitting on the driver's seat 8, various operation pedals 11 (an accelerator pedal, a brake pedal, a clutch pedal) are provided.

[0019] Also, a lifting device 13 for raising and lowering the implement 6 is provided at the rear part of the traveling vehicle body 2. The lifting device 13 moves the implement 6 to the non-working position by raising the implement 6. Also, the lifting device 13 moves the implement 6 to the ground working position by lowering the implement 6. The lifting device 13 includes a hydraulic lifting cylinder 131, a lift arm 132, a lift rod 133, a lower link 134, and a top link 135.

[0020] When hydraulic fluid is supplied to the lifting cylinder 131, the lift arm 132 rotates around axis AX to raise the work implement 6, and when the hydraulic fluid is discharged from the lifting cylinder 131, it rotates around axis AX to lower the work implement 6. A lift arm sensor for detecting the rotation angle of the lift arm 132 is provided at the base of the lift arm 132 (near axis AX). The height of the work implement 6 is calculated based on the value detected by the lift arm sensor.

[0021] Furthermore, the lift arm 132 is connected to the lower link 134 via the lift rod 133. In this way, the lifting device 13 connects the work equipment 6 to the vehicle body 2 via the lower link 134 and the top link 135 so that it can be raised and lowered.

[0022] In the example shown in Figure 1, the working machine 6 is a rotary tiller. The rotary tiller tills the field surface (soil) by rotating the tilling tines 61 with power transmitted from the PTO shaft 71 of the PTO device 7.

[0023] Furthermore, the tractor 1 is equipped with a control unit 200 (see Figure 2). The control unit 200 controls the engine E and the travel speed of the vehicle body 2. The control unit 200 also controls the implement 6.

[0024] Furthermore, the tractor 1 is equipped with a positioning device 150. The positioning device 150 is mounted on the upper part of the vehicle body 2 and measures the position of the vehicle body 2 at predetermined intervals and acquires information (for example, latitude and longitude) of the vehicle body 2's own position P0 (see Figure 3). The positioning device 150 is, for example, a GNSS (Global Navigation Satellite System) and can perform positioning and timing by receiving radio waves from navigation satellites S orbiting overhead.

[0025] Furthermore, the tractor 1 allows the operator to set various tasks in a specific field by operating a portable terminal device 160. The portable terminal device 160 is, for example, a tablet device that can connect to a communication network such as the internet and can connect to a work management device via the communication network. In this case, the work management device is a system that is capable of so-called cloud computing. The portable terminal device 160 and the work management device are connected, for example, via a wireless LAN (Local Area Network).

[0026] The mobile terminal device 160 includes a storage unit, such as a hard disk, ROM (Read Only Memory), and RAM (Random Access Memory), and a display unit and operation unit, which are configured as a touch panel. Various keys and buttons may be provided separately as part of the operation unit. Furthermore, the mobile terminal device 160 may include a processing unit, such as a CPU (Central Processing Unit), to enable electronic control of each component, similar to the control unit 200 described later.

[0027] A work management device is a computer equipped with a processing unit such as a CPU, storage devices such as ROM (Read Only Memory), RAM (Random Access Memory), and HDD (Hard Disk Drive), and input / output devices.

[0028] Furthermore, the tractor 1 is equipped with an azimuth acquisition means 170 (see Figure 2). The azimuth acquisition means 170 acquires the azimuth of the vehicle body. The azimuth acquisition means 170 is, for example, an azimuth sensor. Hereinafter, the azimuth acquisition means 170 will be referred to as the azimuth sensor.

[0029] The azimuth sensor 170 detects, for example, the absolute azimuth of the direction of travel of the vehicle body 2 (for example, with "north" as 0° (360°), "east" as 90°, "south" as 180°, and "west" as 270°). The azimuth sensor 170 detects the absolute azimuth at regular intervals and transmits the detected absolute azimuth to the control unit 200 or the like. In addition to the azimuth sensor, the azimuth acquisition means 170 may also include, for example, a geomagnetic sensor.

[0030] <Control system for work vehicles (tractors)> Next, with reference to Figure 2, the control system 100 of the work vehicle according to the embodiment, that is, the control system of the work vehicle (tractor) 1 centered on the control unit 200, will be described. Figure 2 is a block diagram of the control system 100 of the work vehicle according to the embodiment. As shown in Figure 2, the control unit 200 includes an engine ECU (Electronic Control Unit) 201, a driving system ECU 202, and a work implement lifting system ECU 203.

[0031] The engine ECU 201 controls the rotational speed of the engine E. The drive system ECU 202 controls the rotation of the drive wheels (rear wheels 4) to control the travel speed of the vehicle body 2 (see Figure 1). The work equipment lifting system ECU 203 controls the lifting device 13 to drive the work equipment 6 up and down.

[0032] The control unit 200 is capable of controlling each part by electronic control and includes a processing unit having a CPU (Central Processing Unit), as well as a storage unit consisting of, for example, a hard disk, ROM (Read Only Memory), RAM (Random Access Memory), etc., which stores necessary data such as various programs and the planned travel route (hereinafter referred to as the work route) R1 of the vehicle body 2, which is set in advance for each field.

[0033] As shown in Figure 2, the control unit 200 is connected to a positioning device (GNSS) 150, an azimuth sensor 170, an engine speed sensor 110, a vehicle speed sensor 111, a gear shift sensor 112, a steering angle sensor 113, and the like. The control unit 200 is also connected to the engine E, a transmission 121, a steering device 122, a lifting device 13, and the like.

[0034] The engine speed sensor 110 detects the rotational speed of the engine E. The vehicle speed sensor 111 detects the driving speed (vehicle speed) of the vehicle body 2 (see Figure 1). The gear shift sensor 112 detects which of the multiple gears the transmission 121 is in. The steering angle sensor 113 detects the steering angle of the front wheels 3 (see Figure 1), which are the steering wheels.

[0035] The control unit 200 receives the following inputs: position information (self-position) of the vehicle body 2 in a field, etc., from the positioning device 150; engine speed from the engine speed sensor 110; vehicle speed from the vehicle speed sensor 111; current gear from the gear shift sensor 112; and steering angle of the front wheels 3 from the steering angle sensor 113. When the vehicle body 2 is autonomously driven, the control unit 200 steers the steering wheel 9 (see Figure 1) by controlling the steering cylinder connected to the steering wheel 9 while feeding back the steering angle of the front wheels 3 using the detected value from the steering angle sensor 113, as described above.

[0036] In the control unit 200, the engine ECU 101 is connected to the engine E, the drive system ECU 102 is connected to the transmission 121 and steering system 122, and the work equipment lifting system ECU 103 is connected to the lifting device 13. The work equipment lifting system ECU 103 raises and lowers the work equipment via the lifting device 13.

[0037] Furthermore, when the vehicle body 2 is to move autonomously, the control unit 200 pre-determines a work path R1 (see Figure 3) for each field according to the work performed by the implement 6, digitizes the data, and stores it in the memory unit. Based on the measurement results of the positioning device 150, the control unit 200 controls the engine E, transmission 121, steering device 122, lifting device 13, etc., so that the vehicle moves along the work path R1 stored in the memory unit and performs the work. The work path R1 is set according to the shape and size of the field, the width, length and number of ridges formed in the field, and the type of crop. The control unit 200 also pre-sets the turning radius when the tractor 1 (vehicle body 2) moves within the field.

[0038] Furthermore, as described above, the control unit 200 is wirelessly connected to, for example, a portable terminal device (tablet terminal) 160 that can be carried by the operator. The control unit 200 controls each part of the tractor 1 based on instruction signals from the portable terminal device 160 operated by the operator. The control unit 200 may also have a database of machine information for the tractor 1 and be configured to allow the exchange of information such as the model number from the portable terminal device 160 or the like.

[0039] <Autonomous driving within the field> Next, the autonomous driving of the work vehicle (tractor) 1 within field F1 will be explained with reference to Figures 3 to 8. Figures 3 and 4 are explanatory diagrams of autonomous driving within field F1, and are schematic diagrams viewed from above the field. Figure 3 shows the case where the distance between the turning radius circle C1 when the vehicle body 2 starts moving and the turning radius circle C2 when it enters the work path R1 is a predetermined distance (for example, 10m) or more, while Figure 4 shows the case where the distance between the turning radius circle C1 when the vehicle body 2 starts moving and the turning radius circle C2 when it enters the work path R1 is less than the predetermined distance.

[0040] Figures 5 and 6 are flowcharts illustrating the process of setting the travel path R2. Figure 6 shows the process of setting a travel path R2 that does not deviate from the no-deviation zone A2. Figure 7 is an explanatory diagram (table) of the route patterns of travel path R2. Figure 8 is an explanatory diagram of (a) a left turn-right turn-left turn route pattern and (b) a right turn-left turn-right turn route pattern.

[0041] For example, in the case of tilling work performed by tractor 1 while autonomously driving, the control unit 200 (see Figure 2) generates a work path R1 in which appropriate turning positions and tilling depths are defined, based on information such as the overall length, overall width, and tread of tractor 1, the capacity of implement 6 (see Figure 1), and the shape and area of ​​field F1.

[0042] Furthermore, worker H can also remotely send instructions to tractor 1 by operating a portable terminal device 160 from a ridge F2 or other location.

[0043] As shown in Figures 3 and 4, tractor 1 enters field F1 from the entrance / exit along the work path R1 and automatically performs tilling work while appropriately turning within the work area A1 set up within field F1. Depending on the program, tractor 1 can also be controlled to exit field F1 from the entrance / exit after tilling work and stop at a predetermined location.

[0044] Tractor 1 (vehicle body 2) performs ground work while circling within a predetermined area inside the ridge F2, i.e., the area inside the edge of field F1, which is designated as the headland area. In the work area A1 inside the headland area, tractor 1 performs ground (plowing) work along the work path R1, alternating between moving straight and turning, from a predetermined work start point P1 to a work end point P2.

[0045] <Setting the route to the starting point of the work> Furthermore, in this embodiment, as shown in Figures 3 and 4, the movement path R2 of the tractor 1 (vehicle body 2) is set so that when the tractor 1 starts work, it moves along an appropriate path to the work start point P1.

[0046] In this case, as shown in Figures 3 and 4, the control unit 200 sets a circle C1 with a turning radius that is tangent to the azimuth vector V1 acquired by the azimuth acquisition means 170 and the self-position P0 acquired by the positioning device 150, and sets a circle C2 with a turning radius that is tangent to the vector V2 of the work path R1 and the work start point P1. The control unit 200 also sets a tangent line L1 to the two turning radius circles C1 and C2. Based on the two turning radius circles C1 and C2 and the tangent line L1, the control unit 200 generates multiple paths.

[0047] Here, the turning radius circle C1, which is tangent to the azimuth vector V1 and the self-position P0, has two forms: the left-turn movement start circle C1L, where the vehicle body 2 begins moving by turning left, and the right-turn movement start circle C1R, where the vehicle body 2 begins moving by turning right. Also, the turning radius circle C2, which is tangent to the vector V2 of the work path R1 and the work start point P1, has two forms: the left-turn entry circle C2L, where the vehicle body 2 enters the work path R1 by turning left, and the right-turn entry circle C2R, where the vehicle body 2 enters the work path R1 by turning right.

[0048] The control unit 200 then selects a circle C1 (C1L, C1R) with a turning radius on either the left or right side of the vehicle body 2, and a circle C2 (C2L, C2R) with a turning radius on either the left or right side of the work start point P1, and sets the shortest path from its own position P0 to the work start point P1 as the movement path R2 from among these multiple (four) paths. The control unit 200 then displays the set movement path R2 on the display screen of the portable terminal device 160.

[0049] When the control unit 200 sets a movement path R2, it generates multiple paths based on two circles C1 and C2 with different turning radii and a tangent line L1, as shown in Figure 5 (step S101).

[0050] Next, the control unit 200 selects the shortest path from multiple paths between its own position P0 and the work start point P1 (step S102). Then, the control unit 200 sets the selected shortest path as the movement path R2 (step S103) and terminates the process.

[0051] With this configuration, during autonomous driving of the tractor 1, a path is generated by smoothly connecting the self-position P0 of the vehicle body 2 with the work start point P1. Since the tractor can move along the shortest path (movement path) R2 among the generated paths, the efficiency of movement to the work start point P1 can be improved, and work can be started smoothly. As a result, work efficiency can be improved.

[0052] Furthermore, as shown in Figures 3 and 4, the control unit 200 sets a deviation prevention area A2 outside the work area A1 to prevent the vehicle body 2 from deviating. Therefore, the vehicle body 2 can travel (move) within the deviation prevention area A2. If, among multiple paths, the shortest path from its own position P0 to the work start point P1 includes a partial path that deviates from the deviation prevention area A2, the control unit 200 excludes the path that includes the partial path. In other words, if a path contains a component (partial path) that deviates from the deviation prevention area A2, that path is excluded.

[0053] The control unit 200 then sets the shortest path from its own position P0 to the work start point P1 as the movement path R2, excluding the path containing the deviation component from the remaining paths. In this case, even if the path containing the deviation component is the shortest path, it is not set as the movement path R2. Similarly, if the next shortest path contains the deviation component, it is not set as the movement path R2. This process is repeated until the shortest path does not contain the deviation component. Furthermore, if all paths contain the deviation component, the control unit 200 does not set the movement path R2 and, for example, displays on the display screen of the mobile terminal device 160 that the movement path R2 cannot be set.

[0054] When the control unit 200 sets a travel path R2 that does not deviate from the deviation-prohibition area A2, it generates multiple paths based on two circles C1 and C2 with different turning radii and a tangent line L1, as shown in Figure 6 (step S201).

[0055] Next, the control unit 200 selects the shortest path from multiple paths between its own position P0 and the work start point P1 (step S202). Then, the control unit 200 determines whether the shortest path includes a portion of the path that deviates from the deviation prohibition area A2 (step S203).

[0056] If the control unit 200 determines that the shortest path includes a portion of the path that deviates from the deviation-prohibited area A2 (step S203: Yes), it selects the shortest path again from the paths that do not include the deviating portion, sets the newly selected shortest path as the travel path R2 (step S204), and terminates the process.

[0057] Furthermore, if the control unit 200 determines that the shortest path does not include a portion of the path that deviates from the deviation-prohibited area A2 (step S203: No), the control unit 200 sets the selected shortest path as the travel path R2 (step S103) and terminates the process. Note that in the processes of steps S203 and S204, the control unit 200 may also determine whether the newly selected shortest path includes a portion of the path that deviates from the deviation-prohibited area A2, and may repeat this process until it determines that the path does not include a portion of the path that deviates from the deviation-prohibited area A2.

[0058] With this configuration, movement can be made along the shortest path (travel path) R2 while preventing deviation from field F1 and contact with ridge F2, thus improving the efficiency of movement to the work starting point P1 while ensuring safety.

[0059] Furthermore, the case where the distance between the circle C1 representing the turning radius when the vehicle body 2 starts moving and the circle C2 representing the turning radius when entering the work path R1 is less than a predetermined distance will be explained further with reference to Figures 7 and 8.

[0060] As shown in Figure 7, if the distance between the turning radius circle C1 when the vehicle body 2 starts moving and the turning radius circle C2 when it enters the work path R1 is greater than or equal to a predetermined distance, the control unit 200 sets the movement path R2 from among four path patterns: left turn-straight-left turn, left turn-straight-right turn, right turn-straight-left turn, and right turn-straight-right turn.

[0061] Furthermore, if the distance between the turning radius circle C1 when the vehicle body 2 starts moving and the turning radius circle C2 when it enters the work path R1 is less than a predetermined distance, the control unit 200 sets the movement path R2 from among the four path patterns of left turn-straight-left turn, left turn-straight-right turn, right turn-straight-left turn, and right turn-straight-right turn, plus two path patterns: left turn-right turn-left turn and right turn-left turn.

[0062] As shown in Figure 8(a), when setting a left-turn-right-left route, the control unit 200 further sets a connecting circle C3 of the turning radius that is tangent to the two turning radius circles C1 and C2. Also, as shown in Figure 8(b), when setting a right-turn-left-right route, the control unit 200 further sets a connecting circle C3 of the turning radius that is tangent to the two turning radius circles C1 and C2.

[0063] With this configuration, even if the distance between the turning radius circle C1 when the vehicle body 2 starts moving and the turning radius circle C2 when it enters the work path R1 is short, the shortest path, the movement path R2, can be set, thereby improving the efficiency of movement to the work start point P1.

[0064] Furthermore, the operator can remotely instruct the vehicle body 2 to start moving using the portable terminal device 160. In this case, the control unit 200 sets the movement path R2 based on its own position P0 and azimuth angle at the time the portable terminal device 160 instructs the vehicle body 2 to start moving, that is, at the time the control unit 200 receives the instruction signal to start moving from the portable terminal device 160. The control unit 200 then moves the vehicle body 2 along the set movement path R2.

[0065] With this configuration, a reasonable route can be set between the point where the mobile terminal device 160 issues a command to start moving, that is, the point where the control unit 200 receives the command signal to start moving from the mobile terminal device 160, and the work start point P1, thereby improving the efficiency of movement to the work start point P1.

[0066] <Travel routes that bypass restricted entry areas and areas where deviation is prohibited> Next, with reference to Figure 9, we will explain the no-entry zone A3 and the movement path R2 that bypasses the no-entry zone A3. Figure 9 is an explanatory diagram of the movement path R2 that bypasses the no-entry zone A3 and the deviation-prohibition zone A2. As shown in Figure 9, the control unit 200 pre-sets the no-entry zone A3 as the inner area of ​​a closed polygon within field F1. The control unit 200 also sets the deviation-prohibition zone A2 as the outer area of ​​the no-entry zone A3.

[0067] The no-entry zone A3 is an area where the vehicle 2 is prohibited from driving, for example, an area that should not be disturbed by the vehicle 2's movement while the vehicle 2 is moving towards the work start point P1. The no-deviation zone A2 is an area where the vehicle 2 is prohibited from deviating, as described above.

[0068] Then, if an entry-restricted area A3 or a deviation-restricted area A2 is set, the control unit 200 sets a travel path R2 that bypasses the entry-restricted area A3 or the deviation-restricted area A2.

[0069] When the control unit 200 sets a no-entry zone A3, it sets a detour circle C4 with a turning radius that bypasses the no-entry zone A3 at vertex p1 of the polygonal no-entry zone A3. The control unit 200 sets a movement path R2 from the self-position P0 of the vehicle body 2 to the work start point P1. If the set movement path R2 enters the no-entry zone A3, the control unit 200 modifies the movement path R2 so that it bypasses the no-entry zone A3 via the detour circle C4.

[0070] The control unit 200 sets the detour circle C4 only for the convex vertex p1a of the vertices p1 of the no-entry area A3. In other words, the control unit 200 does not set the detour circle C4 for the concave vertex p1b of the no-entry area A3.

[0071] Furthermore, if the movement path R2 that bypasses the no-entry area A3 includes a path R2c (see Figure 12), which deviates from the no-deviation area A2, the control unit 200 modifies the path R2c that deviates from the no-deviation area A2 to pass through the bypass circle C5 set at the vertex p2 of the no-deviation area A2.

[0072] The control unit 200 sets the detour circle C5 only at the concave vertex p2b of the vertex p2 of the deviation-prohibition area A2. In other words, the control unit 200 does not set the detour circle C5 at the convex vertex p1a of the deviation-prohibition area A2.

[0073] <Setting detour routes for restricted areas> Next, the setting of the detour route (travel path R2) for the restricted area A3 will be explained with reference to Figures 10 and 11. Figures 10 and 11 are explanatory diagrams for setting the detour route (travel path R2) for the restricted area A3.

[0074] As shown in Figures 10 and 11, the control unit 200 sets the movement path R2 based on a circle C1 with a turning radius that is tangent to the azimuth vector V1 and its own position P0, a circle C2 with a turning radius that is tangent to the vector V2 of the work path R1 and the work start point P1, the two circles C1 and C2 with turning radii, and the tangent line L2 (see Figure 9) to the bypass circle C4 of the no-entry area A3.

[0075] As shown in Figure 10, when the control unit 200 sets an entry-restricted area A3, it sets the entry-restricted area A3 by connecting the vertices p1 based on the order of the vertices p1 specified by the worker. When specifying the vertices p1, it is preferable to specify them in a clockwise or counterclockwise order (in the examples shown in Figures 10 and 11, the order is a1, a2, ... a7, or the order is a7, a6, ... a1). Note that the order is a1, a2, ... a7, and the order is a7, a6, ... a1, which is called ascending order.

[0076] The control unit 200 stores each edge of the restricted area A3 as a vector Vs1 based on the order of the specified vertices p1. The control unit 200 calculates the cross product of adjacent vectors Vs1 from the stored vectors Vs1. Based on the calculated value of the cross product, the control unit 200 determines whether vertex p1 is a convex vertex p1a or a concave vertex p1b. In this case, the value of the cross product determines whether vertex p1 is a convex vertex p1a or a concave vertex p1b. If the value of the cross product is positive, it is determined to be a convex vertex p1a, and if the value of the cross product is negative, it is determined to be a concave vertex p1b.

[0077] Here, the portable terminal device 160 (see Figure 2) is operated by a worker or other person when setting the no-entry area A3. When setting the no-entry area A3, the portable terminal device 160 displays instructions to specify the vertices p1 in a clockwise or counterclockwise order. The control unit 200 sets the no-entry area A3 by connecting the vertices p1 based on the order of the vertices p1 specified by the portable terminal device 160.

[0078] As shown in Figure 10, the control unit 200 first sets the shortest path (movement path R2) from its own position P0 to the work start point P1, based on the turning radius circle C1, the turning radius circle C2, and the tangent line L1 to the two turning radius circles C1 and C2 (see Figure 3).

[0079] If the movement path R2 includes a path R2a that enters a restricted area A3, the control unit 200 modifies the path R2a that enters the restricted area A3 so that it passes through a detour circle C4, which is set in ascending order based on a specified sequence, starting from the vertex p1 adjacent to the work start point P1 (vertex p1 at position a1). In the example shown in Figure 10, the vertex p1 at position a2 is modified to pass through the detour circle C4.

[0080] As shown in Figure 11, if a path R2a that enters the restricted area A3 within the movement path R2 is not eliminated, the path R2a that enters the restricted area A3 is modified so that vertex p1 (vertex p1 at position a4) is bypassed by the circle C4.

[0081] In this way, the control unit 200 modifies the route to pass through the detour circles C4, which are set in ascending order based on the specified sequence, and when there are no more routes R2a that enter the restricted area A3, it sets route R2b as a route within the travel route R2. Note that the examples shown in Figures 10 and 11 pass through the detour circles C4, which are set in ascending order, but the system may also be configured to pass through the detour circles C4, which are set in descending order based on the specified sequence.

[0082] With this configuration, during autonomous driving, the vehicle body 2 can smoothly connect its own position P0 to the work start point P1 to generate a traversable path. If there is an area within the field F1 that should not be disturbed, it can be set as a no-entry zone A3 for the vehicle body 2, and a traversal path R2 can be set to bypass the no-entry zone A3. This improves the efficiency of movement to the work start point P1 while bypassing the no-entry zone A3. As a result, work efficiency can be improved.

[0083] Furthermore, by setting a detour circle C4 only at the convex vertex p1a of the polygonal restricted area A3, it is possible to bypass the restricted area A3 via the shortest path by connecting the set detour circles C4. However, even if a detour circle C4 is set at the concave vertex p1b of the polygonal restricted area A3, smooth movement while avoiding entry into the restricted area A3 is not possible.

[0084] Furthermore, by specifying each vertex p1 of the polygonal no-entry zone A3 in a clockwise (or counterclockwise) order, the no-entry zone A3 can be precisely defined.

[0085] Furthermore, by sequentially specifying each vertex p1 of the polygonal no-entry zone A3, it is possible to determine whether vertex p1 is a convex vertex p1a or a concave vertex p1b based on the value of the cross product of the adjacent side vectors Vs1, i.e., whether the value of the cross product is positive or negative. Therefore, the necessary information for the no-entry zone A3 can be set with simple operations.

[0086] Furthermore, if the movement path R2 includes a path R2a that enters a restricted area A3, the path R2a that enters the restricted area A3 is modified to pass through detour circles C4, which are set in ascending (or descending) order based on a specified sequence, starting from the vertex p1 adjacent to the work start point P1. This allows for the omission of movement through the unnecessary detour circles C4, resulting in a more efficient movement path R2.

[0087] The control unit 200 then sets the movement path R2 based on a circle C1 with a turning radius that is tangent to the azimuth vector V1 and its own position P0, a circle C2 with a turning radius that is tangent to the vector V2 of the work path R1 and the work start point P1, and a tangent L2 to the two circles C1 and C2 with turning radii and the bypass circle C4 of the no-entry area A3.

[0088] This allows for smooth turning and direction changes, improving the efficiency of movement to the work start point P1 while bypassing the restricted area A3, and enabling a smooth commencement of work.

[0089] Furthermore, the control unit 200 may be configured to generate two paths: one that bypasses the restricted area A3 clockwise and another that bypasses the restricted area A3 counterclockwise, and to set the shorter of the two generated paths as the movement path R2. This makes it possible to improve the efficiency of movement to the work start point P1 while bypassing the restricted area A3, and to start work smoothly.

[0090] <Setting a detour route for the no-deviation zone> Next, the setting of the detour route (travel path R2) for the no-deviation zone A2 will be explained with reference to Figures 12 and 13. Figures 12 and 13 are explanatory diagrams for setting the detour route (travel path R2) for the no-deviation zone A2.

[0091] As shown in Figure 12, when the control unit 200 sets the deviation-prohibition area A2, it sets the deviation-prohibition area A2 by connecting the vertices p2 based on the order of the vertices p2 specified by the operator. When specifying the vertices p2, it is preferable to specify the vertices p2 in a clockwise or counterclockwise order (in the examples shown in Figures 12 and 13, the order is b1, b2, ... b7, or b7, b6, ... b1). Note that the order is called ascending order, and the order is called descending order.

[0092] The control unit 200 stores each edge of the deviation-prohibition region A2 as a vector Vs2 based on the order of the specified vertices p2. The control unit 200 calculates the cross product of adjacent vectors Vs2 from the stored vectors Vs2. Based on the calculated value of the cross product, the control unit 200 determines whether vertex p2 is a concave vertex p2b or a convex vertex p2a. In this case, the value of the cross product determines whether vertex p2 is a concave vertex p2b or a convex vertex p2a. If the value of the cross product is positive, it is determined to be a convex vertex p2a, and if the value of the cross product is negative, it is determined to be a concave vertex p2b.

[0093] Here, the portable terminal device 160 (see Figure 2) is operated by a worker or other person when setting the deviation-prohibition area A2. When setting the deviation-prohibition area A2, the portable terminal device 160 displays instructions to specify the vertices p2 in a clockwise or counterclockwise order. The control unit 200 sets the deviation-prohibition area A2 by connecting the vertices p2 based on the order of the vertices p2 specified by the portable terminal device 160.

[0094] As shown in Figure 12, if the movement path R2 includes a path R2c that enters the deviation-prohibition area A2, the control unit 200 modifies the path R2c that enters the deviation-prohibition area A2 so that it bypasses vertex p2 (vertex p2 at position b3) via the detour circle C5.

[0095] In this way, the control unit 200 modifies the route to go through the detour circle C5, and when there are no longer any routes R2c that enter the deviation-prohibition area A2, it sets route R2d as a route within the travel route R2. If there are multiple detour circles C5, the control unit 200 may be configured to go through the route in descending order or in descending order based on the specified order.

[0096] With this configuration, if the movement path R2 that bypasses the no-entry area A3 includes a path R2c that deviates from the no-deviation area A2, the path R2c that deviates from the no-deviation area A2 is modified to pass through a detour circle C5 set at the concave apex p2b of the no-deviation area A2. This allows movement along the shortest movement path R2 while preventing deviation from field F1 and contact with ridge F2, thus improving the efficiency of movement to the work start point P1 while bypassing the no-entry area A3, while ensuring safety.

[0097] Furthermore, by sequentially specifying each vertex p2 of the no-deviation zone A2, it is possible to determine whether vertex p2 is a convex vertex p2a or a concave vertex p2b based on the value of the cross product, i.e., whether the value of the cross product is positive or negative. Therefore, the necessary information for the no-deviation zone A2 can be set with simple operations, and the efficiency of moving to the work start point while bypassing the no-entry zone A3 can be improved.

[0098] The control unit 200 then sets the movement path R2 based on a circle C1 with a turning radius that is tangent to the azimuth vector V1 and its own position P0, a circle C2 with a turning radius that is tangent to the vector V2 of the work path R1 and the work start point P1, and a tangent L2 to at least one of the two circles C1 and C2 with turning radii, and the bypass circle C4 of the no-entry area A3 and the bypass circle C5 of the no-deviation area A2.

[0099] This allows for smooth turning and direction changes, improving the efficiency of movement to the work start point P1 while bypassing the restricted area A3, and enabling a smooth commencement of work.

[0100] The above-described embodiments realize the following control system 100 for work vehicles.

[0101] (1) The vehicle comprises a vehicle body 2 capable of traveling within field F1, a positioning device 150 that acquires the vehicle body 2's own position P0, an azimuth angle acquisition means 170 that acquires the azimuth angle of the vehicle body 2, and a control unit 200 that generates a work path R1 including a work start point P1 within field F1 and controls the vehicle body 2 to perform work while autonomously traveling along the generated work path R1, wherein the control unit 200 determines the turning radius of the vehicle body 2 when it moves within field F1 and the inner region of a closed polygon within field F1. A control system 100 for a work vehicle pre-sets an entry-restricted area A3 that prohibits the entry of the vehicle body 2, and when the entry-restricted area A3 is set, it sets a detour circle C4 with a turning radius that bypasses the entry-restricted area A3 at the vertex p1 of the entry-restricted area A3, sets a movement path R2 from the vehicle body 2's own position P0 to the work start point P1, and if the set movement path R2 enters the entry-restricted area A3, it modifies the movement path R2 to bypass the entry-restricted area A3 via the detour circle C4.

[0102] According to this control system 100 for work vehicles, during autonomous driving, a path is generated that smoothly connects the vehicle's own position P0 and the work start point P1. If there is an area in the field F1 that should not be disturbed, it is set as a no-entry zone A3 for the vehicle 2, and a movement path R2 that bypasses the no-entry zone A3 is set, thereby improving the efficiency of movement to the work start point P1 while bypassing the no-entry zone A3. This improves work efficiency.

[0103] (2) In the above (1), the control unit 200 is a control system 100 for a work vehicle that sets the detour circle C4 only to the convex vertex p1a among the vertices p1 of the no-entry area A3.

[0104] According to such a control system 100 for work vehicles, in addition to the effects of (1) above, for example, even if a detour circle C4 is set at the concave vertex p1b of the polygonal no-entry area A3, smooth movement while avoiding entry into the no-entry area A3 is not possible. Therefore, by setting the detour circle C4 only at the convex vertex p1a and connecting the set detour circles C4, it is possible to bypass the no-entry area A3 via the shortest path, thereby improving the efficiency of movement to the work start point P1 while bypassing the no-entry area A3.

[0105] (3) A control system 100 for a work vehicle that is operated when setting an entry-restricted area A3 as described in (1) or (2) above, wherein the portable terminal device 160 displays instructions to specify the vertices p1 in a clockwise or counterclockwise order when setting the entry-restricted area A3, and the control unit 200 connects the vertices p1 based on the specified order to set the entry-restricted area A3.

[0106] According to such a control system 100 for work vehicles, in addition to the effects of (1) or (2) above, by specifying each vertex p1 of the polygonal no-entry area A3 in a clockwise or counterclockwise order, the no-entry area A3 can be precisely set, and the efficiency of moving to the work start point P1 while bypassing the no-entry area A3 can be improved.

[0107] (4) In the above (3), the control unit 200 stores each edge of the no-entry area A3 as a vector Vs1 based on the order of the specified vertices p1, calculates the cross product of adjacent vectors Vs1, and determines whether or not a vertex p1 is a convex vertex p1a based on the calculated value of the cross product, and is a control system 100 for a work vehicle.

[0108] According to this control system 100 for work vehicles, in addition to the effects of (3) above, by sequentially specifying each vertex p1 of the polygonal no-entry area A3, it is possible to determine whether vertex p1 is a convex vertex p1a or a concave vertex p1b based on the value of the cross product of the vectors Vs1 of adjacent sides, that is, whether the value of the cross product is positive or negative. Therefore, the necessary information for the no-entry area A3 can be set with simple operations, and the efficiency of moving to the work start point P1 while bypassing the no-entry area A3 can be improved.

[0109] (5) In (3) or (4) above, if the control unit 200 includes a route R2a that enters the restricted area A3 within the movement path R2, the control unit 200 modifies the route R2a that enters the restricted area A3 to pass through detour circles C4 which are set in ascending or descending order based on a specified order, starting from the vertex p1 adjacent to the work start point P1 among the vertices p1, and when there are no more routes R2a that enter the restricted area A3, the control system 100 for the work vehicle sets route R2b as a route within the movement path R2.

[0110] With such a work vehicle control system 100, in addition to the effects of (3) or (4) above, it is possible to set an efficient travel path R2 by eliminating the need to travel through the detour circle C4, thereby improving the efficiency of travel to the work start point P1 while bypassing the no-entry area A3.

[0111] (6) In any one of (1) to (5) above, the control unit 200 sets a deviation restriction area A2 outside the no-entry area A3 to prohibit the vehicle body 2 from deviating, and if the travel path R2 that bypasses the no-entry area A3 includes a path R2c that deviates from the deviation restriction area A2, the control system 100 for the work vehicle changes the path R2c that deviates from the deviation restriction area A2 to pass through a detour circle C5 set at the concave vertex p2b of the deviation restriction area A2.

[0112] According to this control system 100 for work vehicles, in addition to any one of the effects of (1) to (5) above, it is possible to move along the shortest possible route R2 while preventing deviation from field F1 or contact with ridge F2, thereby improving the efficiency of movement to the work start point P1 while bypassing the no-entry area A3, while ensuring safety.

[0113] (7) A control system for a work vehicle, comprising a portable terminal device 160 which is operated when setting a no-deviation area A2 as described in (6) above, wherein the portable terminal device 160 displays guidance to specify vertices p2 in a clockwise or counterclockwise order when setting the no-deviation area A2, the control unit 200 sets the no-deviation area A2 by connecting the vertices p2 based on the specified order of vertices p2, stores each edge s2 of the no-deviation area A2 as a vector Vs2 based on the specified order of vertices p2, calculates the cross product of adjacent vectors Vs2, and determines whether a vertex p2 is a concave vertex p2b based on the calculated value of the cross product.

[0114] According to this control system 100 for work vehicles, in addition to the effects of (6) above, by sequentially specifying each vertex p2 of the no-deviation zone A2, it is possible to determine whether vertex p2 is a convex vertex p2a or a concave vertex p2b based on the value of the cross product, that is, whether the value of the cross product is positive or negative. Therefore, the necessary information for the no-deviation zone A2 can be set with simple operations, and the efficiency of moving to the work start point while bypassing the no-entry zone A3 can be improved.

[0115] (8) In any one of (1) to (7) above, the control unit 200 sets a deviation prevention area A2 outside the no-entry area A3 to prevent the vehicle body 2 from deviating, and sets a movement path R2 based on the azimuth vector V1 acquired by the azimuth acquisition means 170 and the turning radius circle C1 that is tangent to the self position P0 acquired by the positioning device 150, the vector V2 of the work path R1 and the turning radius circle C2 that is tangent to the work start point P1, the two turning radius circles C1 and C2 and the tangent L2 to the bypass circle C4 of the no-entry area A3 and / or the bypass circle C5 of the deviation prevention area A2.

[0116] With this type of work vehicle control system 100, in addition to any one of the effects of (1) to (7) above, it becomes possible to change direction by turning smoothly, which improves the efficiency of moving to the work start point P1 while bypassing the no-entry area A3, and allows work to start smoothly.

[0117] (9) In any one of the above (1) to (8), the control unit 200 generates a route that bypasses the no-entry area A3 clockwise and a route that bypasses the no-entry area A3 counterclockwise, and sets the shorter of the two generated routes as the travel route R2, a control system 100 for a work vehicle.

[0118] With this type of work vehicle control system 100, in addition to any one of the effects of (1) to (8) above, it is possible to improve the efficiency of moving to the work start point P1 while bypassing the no-entry area A3, and to start work smoothly.

[0119] Further effects and modifications can be readily derived by those skilled in the art. Therefore, broader aspects of the present invention are not limited to the specific details and representative embodiments expressed and described above. Accordingly, various modifications are possible without departing from the spirit or scope of the overall concept of the invention as defined by the appended claims and their equivalents. [Explanation of Symbols]

[0120] 1. Work vehicle (tractor) 2. Running vehicle 3 Front wheels 4 Rear wheels 5. Hood 6. Work equipment 7 PTO device 8. Cockpit 9. Steering wheel 10 Handlebar Post 11. Operating pedals 12 Power transmission system (transmission case) 13 Lifting device 61 Cultivating Claw 71 PTO shaft 131 Lifting Cylinder 132 Lift Arm 133 Lift Rod 134 Lower Link 135 Top Links 100 Control systems for work vehicles 110 Engine speed sensor 111 Vehicle speed sensor 112 Gear shift sensor 113 Steering Angle Sensor 121 Transmission 122 Steering System 150 Positioning devices (GNSS) 160 Mobile devices (tablet devices) 170. Azimuth acquisition method (azimuth sensor) 200 Control Unit 201 Engine ECU 202 Driving system ECU 203 Work equipment lifting system ECU AX axis A1 work area A2 No deviation area A3 No entry area C1 Circle of turning radius C2 Circle with turning radius C3 Connection Circle C4 Bypass Circle C5 Bypass Circle E-engine F1 field F2 ridge H worker L1 tangent L2 tangent P0 Self-position P1 Work starting point P2 End of work point p1 vertex p1a Convex vertex p1b Concave vertex p2 vertex p2a Convex vertex p2b Concave vertex R1 Work Route R2 Travel Path Route R2a R2b route S Navigation Satellite V1 Vector V2 Vector Vs1 Vector Vs2 Vector

Claims

1. A vehicle capable of traveling within a field, A positioning device that acquires the self-position of the vehicle body, A means for acquiring the azimuth angle of the vehicle body, The system includes a control unit that generates a work path including the starting point of work within the field, and controls the vehicle body to perform work while autonomously driving along the generated work path, The control unit, The turning radius of the vehicle body when moving within the field and the no-entry zone, which is the inner area of ​​a closed polygon within the field and prohibits the vehicle body from entering, are set in advance. A deviation prevention area is set outside the aforementioned no-entry area. The aforementioned deviation prevention area is an area that prohibits the vehicle from deviating outside the closed polygon. Determine whether each vertex of the aforementioned no-entry zone is a convex or concave vertex. Determine whether each vertex of the aforementioned deviation-prohibited region is a convex or concave vertex. A movement path is set for the vehicle body from its own position to the work start point. If the aforementioned travel path enters the restricted area, the travel path entering the restricted area is modified to pass through a detour circle set at the convex vertex of the restricted area. If the movement path deviates from the deviation-prohibition area, the movement path is modified to pass through a detour circle set at the concave vertex of the deviation-prohibition area. The detour circle shall not be set at the concave vertices of the no-entry zone or the convex vertices of the no-deviation zone. A control system for work vehicles characterized by the following.

2. Each vertex of the aforementioned no-entry zone is assigned a specific order, and the modification of the movement path is performed by sequentially modifying it to pass through the detour circle in ascending or descending order, starting from the convex vertex adjacent to the work start point, based on the assigned order. A control system for a work vehicle according to claim 1, characterized by the above.

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