WO2020039782A1

WO2020039782A1 - Automatic traveling system for work vehicle

Info

Publication number: WO2020039782A1
Application number: PCT/JP2019/027385
Authority: WO
Inventors: 健太池乗; 優飛兒玉
Original assignee: ヤンマー株式会社
Priority date: 2018-08-22
Filing date: 2019-07-10
Publication date: 2020-02-27
Also published as: JP7091189B2; JP2020028243A

Abstract

In the present invention, work efficiency is improved by increasing the vehicle speed of a work vehicle in a work area within a work field while the work area is widened. This automatic traveling system for a work vehicle has a vehicle speed control unit (42), a storage unit (47) for storing a target path, and an automatic traveling control unit (46) for causing a work vehicle (1) to perform automatic traveling according to the target path by use of a satellite positioning system. The target path includes a plurality of parallel paths arranged in parallel in a traveling area in a field and a plurality of turning paths for connecting, in a traveling order, the plurality of parallel paths in an outer edge part of the traveling area. The automatic traveling control unit (46) has a separation distance measurement unit (46A) that, when the work vehicle is performing automatic traveling on a parallel path, measures a separation distance, in the work vehicle advancing direction, from the work vehicle to the outer peripheral edge of the work field. The vehicle speed control unit (42) has a vehicle speed limitation unit (42A) that limits the vehicle speed of the work vehicle in accordance with the separation distance.

Description

Automatic driving system for work vehicles

The present invention relates to an automatic traveling system for a work vehicle that makes a work vehicle automatically travel along a target route using a satellite positioning system.

2. Description of the Related Art Conventionally, as a method of automatically driving a work vehicle according to a target route using a satellite positioning system, a work vehicle (autonomous travel work vehicle) is moved to a target route (travel route) generated according to a work place (field). When the work vehicle enters the turning area (headland turning area) on the outer edge side of the work place, the control device operates the speed change means to reduce the vehicle speed of the working vehicle to the turning speed (headland turning speed). There is a control device for a work vehicle that is configured to turn the work vehicle at a turning speed in a turning area by decelerating the work vehicle to the turning speed (for example, see Patent Document 1).

International Publication No. WO 2015/147108

Usually, a target route used when a work vehicle such as a tractor is automatically driven includes a plurality of parallel routes arranged in parallel in a traveling area divided in a work place, and a plurality of parallel paths arranged on an outer edge side of the traveling area. And a plurality of turning paths connecting the parallel paths in the running order. Each of the parallel paths includes a work path for making the work vehicle work in the work area set at the center side of the travel area, and a work area where the work vehicle turns from the work path in the turn area set on the outer edge side of the travel area. A non-work route in which the work vehicle travels in a work stopped state before reaching the route is included.

In the control device for a work vehicle described in Patent Literature 1, for example, if the speed of the work vehicle on the work route included in the target route is increased in order to improve work efficiency, the work vehicle enters a turning area. The braking distance required to reduce the vehicle speed of the work vehicle to the turning speed increases. Therefore, the turning area in the work place becomes wider and the work area becomes narrower. Since the work area is an area in which the work vehicle performs the work while automatically traveling, when the work area is narrow, the area in which the user performs the work while manually moving the work vehicle in the work place becomes large, and the burden on the user is increased. Becomes larger.

Therefore, it is conceivable to widen the work area in order to reduce the burden on the user. In this case, the turning area becomes narrower, and the vehicle speed of the work vehicle is reduced after the work vehicle enters the turning area. The braking distance required to lower the Therefore, the vehicle speed of the work vehicle in the work area is reduced, and the work efficiency is reduced. Also, if the vehicle speed of the work vehicle on the work route is increased while the work area is widened, the vehicle speed of the work vehicle is changed from the turn of the work vehicle to the turning speed (headland turning) after the work vehicle enters the turning region. Can no longer be reduced. As a result, there is a possibility that the work vehicle may protrude from the work place during turning and come into contact with other objects such as ridges.

In view of this situation, a main problem of the present invention is to improve the work efficiency by increasing the speed of a work vehicle in a work area while widening the work area in the work area.

A first characteristic configuration of the present invention is an automatic traveling system for a work vehicle,
A vehicle speed control unit that controls the vehicle speed of the work vehicle;
A storage unit for storing a target route generated according to the traveling area divided in the work place,
An automatic travel control unit that automatically travels the work vehicle according to the target route using a satellite positioning system,
The target path includes a plurality of parallel paths arranged in parallel in the traveling area, and a plurality of turning paths arranged at an outer edge of the traveling area and connecting the plurality of parallel paths in the traveling order. Yes,
The automatic traveling control unit is configured to measure a separation distance from the work vehicle to an outer peripheral edge of the work place in a traveling direction of the work vehicle when the work vehicle is automatically traveling on the parallel path. Part
The vehicle speed control unit has a vehicle speed limiting unit that limits the vehicle speed of the work vehicle according to the separation distance.

According to this configuration, when the work vehicle is automatically traveling on the parallel route, the vehicle speed limiting unit is configured to control the separation distance measured by the separation distance measurement unit regardless of the work area or the turning area set in the work place. The vehicle speed of the work vehicle is limited according to the condition.

Specifically, while the work vehicle traveling on the reciprocating route is far away from the outer edge of the work site located in the traveling direction, the separation distance measured by the separation distance measurement unit is long, so the vehicle speed limiting unit is The speed limit of the work vehicle on the reciprocating route is increased according to the separation distance. That is, it is possible to improve work efficiency by increasing the vehicle speed of the work vehicle.

When the work vehicle traveling on the reciprocating route approaches the outer peripheral edge of the work site located in the traveling direction, the separation distance measured by the separation distance measurement unit becomes short. Accordingly, the speed limit of the work vehicle in the reciprocating path is reduced so that the braking distance of the work vehicle is shorter than the separation distance. In other words, regardless of the work area and the turning area set in the work place, when the work vehicle approaches the outer periphery of the work place, the vehicle speed limiting unit adjusts the outer periphery of the work place according to the separation distance at that time. The speed limit at which the work vehicle can be stopped by braking is set to reduce the vehicle speed of the work vehicle. This prevents the automatic traveling control unit from protruding from the work place when the work vehicle stops traveling near the outer peripheral edge of the work place according to the parallel path or when the work vehicle is turned along the turning path. The work vehicle can be prevented from contacting another object such as a ridge due to the protrusion.

In other words, it is possible to increase the speed of the work vehicle in the work area while widening the work area in which the work vehicle performs work while automatically traveling in the work area. As a result, the burden on the user can be reduced, and work efficiency can be improved.

A second characteristic configuration of the present invention is:
The target route includes a target vehicle speed when the work vehicle automatically travels on the parallel route,
The vehicle speed limiter calculates a comparative braking distance shorter than the separation distance by a set distance, and while the braking distance of the work vehicle according to the target vehicle speed is shorter than the comparative braking distance, the vehicle speed of the work vehicle Performs a first vehicle speed limiting process for limiting the vehicle speed of the work vehicle so that the target vehicle speed is maintained, and when a braking distance of the work vehicle according to the target vehicle speed becomes equal to the comparative braking distance, And a second vehicle speed limiting process for reducing the vehicle speed of the work vehicle from the target vehicle speed in accordance with the decrease in the separation distance so that the brake distance of the work vehicle is maintained at the comparative brake distance.

According to this configuration, while the separation distance is long and the braking distance of the work vehicle according to the target vehicle speed is shorter than the comparison braking distance, the vehicle speed limitation unit performs the first vehicle speed limitation process to execute the vehicle speed limitation of the work vehicle. To the target vehicle speed. As a result, fuel efficiency may be degraded due to unnecessarily increasing the vehicle speed of the work vehicle, and the work vehicle may be less able to follow the target route when the work vehicle automatically travels along the target route. Can be avoided.

When the separation distance becomes short and the braking distance of the work vehicle according to the target vehicle speed becomes the same as the comparison braking distance, the vehicle speed restriction unit performs the second vehicle speed restriction process, thereby performing the braking distance of the work vehicle. However, the vehicle speed of the work vehicle is limited so that the comparative braking distance becomes shorter as the separation distance decreases. Thus, when the work vehicle approaches the outer peripheral edge of the work place or reaches a turning path, the vehicle speed of the work vehicle can be sufficiently reduced. As a result, when the automatic traveling control unit stops the traveling of the work vehicle near the outer periphery of the work place according to the parallel route, or when the work vehicle turns around according to the turning route, the work vehicle protrudes from the work place and ridges or the like. The possibility of contact with other objects can be more reliably avoided.

A third characteristic configuration of the present invention is:
The storage unit includes a turning radius of the work vehicle, a work width of the work vehicle, a margin width set between an outer peripheral edge of the work place and the traveling area, the parallel path, and the turn path. Each connection point with is stored,
The separation distance measurement unit, the current position of the work vehicle in the parallel path obtained using the satellite positioning system, and the connection point on the terminal side in the parallel path stored in the storage unit, The separation distance is measured based on a turning radius of the work vehicle, a work width of the work vehicle, and the margin width.

According to this configuration, for example, at a stage before the work vehicle automatically travels on the parallel path, the separation distance measurement unit determines a turning radius of the work vehicle, a half length of the work width of the work vehicle, and a margin of the work place. By adding the width, the fixed separation distance from the connection point on the end side of the parallel path to the outer peripheral edge of the work site is calculated and stored in the storage unit. Then, while the work vehicle is automatically traveling on the parallel route, the separation distance measurement unit calculates the untraveled distance between the current position of the work vehicle and the connection point on the end side of the parallel route, The above-mentioned fixed distance is added to this untraveled distance to measure the above-mentioned distance.

That is, the separation distance measurement unit calculates the untraveled distance that changes according to the current position of the work vehicle on the parallel route obtained using the satellite positioning system, and the fixed separation distance that is a fixed value stored in the storage unit. The separation distance will be measured based on the distance. As a result, the calculation load required for measuring the separation distance can be reduced, and as a result, the separation distance can be measured quickly and accurately.

A fourth characteristic configuration of the present invention is:
The storage unit stores a plurality of shape specifying points in the work place acquired by using the satellite positioning system, and a shape specifying line that connects the plurality of shape specifying points to specify the shape of the work place. And
The separation distance measurement unit is configured to measure a distance from a current position of the work vehicle on the parallel path acquired using the satellite positioning system to a shape identification line located on an extension of the parallel path in the traveling direction of the work vehicle. The point is that the distance is measured as the separation distance.

According to this configuration, the separation distance measuring unit can relatively easily measure the separation distance while using the shape specifying line acquired when specifying the shape of the work place using the satellite positioning system. .

A fifth characteristic configuration of the present invention is:
The work vehicle is provided with a distance sensor that measures a distance to a distance measurement target existing in a traveling direction of the work vehicle,
The separation distance measurement unit is configured to measure the separation distance based on a measurement result of the distance sensor.

According to this configuration, the separation distance can be accurately measured based on the measurement result of the distance sensor without using the satellite positioning system.

Diagram showing a schematic configuration of an automatic traveling system for a work vehicle FIG. 2 is a block diagram showing a schematic configuration of an automatic traveling system for a work vehicle. Diagram showing an example of a target route generated by a target route generation unit Flow chart of target route generation control Explanatory drawing about measurement of separation distance by separation distance measurement unit Graph showing the relationship between separation distance and vehicle speed Explanatory diagram regarding measurement of separation distance by separation distance measurement unit and measurement of comparative braking distance by vehicle speed limit unit Graph showing the relationship between separation distance and upper limit speed Flowchart of vehicle speed limit control Explanatory drawing about measurement of separation distance by separation distance measurement part in another embodiment.

Hereinafter, as an example of an embodiment for carrying out the present invention, an embodiment in which an automatic traveling system for a work vehicle according to the present invention is applied to a tractor as an example of a work vehicle will be described with reference to the drawings.
The automatic traveling system for a work vehicle according to the present invention includes a work vehicle other than a tractor, such as a riding mower, a riding rice transplanter, a combine, a wheel loader, a snowplow, and an unmanned mowing machine. It can be applied to work vehicles.

As shown in FIG. 3, the tractor 1 exemplified in this embodiment is configured to be able to automatically travel in a field A or the like, which is an example of a work place, by an automatic travel system for a work vehicle. As shown in FIGS. 1 and 2, the automatic traveling system is a mobile communication terminal that is an example of an automatic traveling unit 2 mounted on a tractor 1 and a wireless communication device that is set to be able to perform wireless communication with the automatic traveling unit 2. 3, etc. As the mobile communication terminal 3, a tablet-type personal computer, a smartphone, or the like having a multi-touch display unit (for example, a liquid crystal panel) 4 that enables various kinds of information display and input operation related to automatic driving can be employed. it can.

As shown in FIG. 1, the tractor 1 has a rotary tilling device 6, which is an example of a working device, connected to a rear portion of the tractor 1 via a three-point link mechanism 5 so as to be able to move up and down and roll. Thus, the tractor 1 is configured for a rotary tilling specification.
In addition, various working devices such as a plow, a disk harrow, a cultivator, a subsoiler, a sowing device, a spraying device, and a mowing device can be connected to the rear portion of the tractor 1 in place of the rotary tilling device 6.

As shown in FIGS. 1 and 2, the tractor 1 has drivable left and right front wheels 10 that can be steered, left and right drivable rear wheels 11, a cabin 13 forming a riding type driving unit 12, and a common rail system. Electronically controlled diesel engine (hereinafter referred to as engine) 14, transmission unit 15 for shifting power from engine 14, fully hydraulic power steering unit 16 for steering left and right front wheels 10, and braking for left and right rear wheels 11 Brake unit 17, an electro-hydraulic control type working clutch unit 19 for intermittently transmitting power to the rotary tilling device 6, an electro-hydraulic control type lifting / lowering drive unit 20 for raising and lowering the rotary tilling device 6, and the rotary tilling device 6 in the roll direction. Rolling drive unit 21 of the electro-hydraulic control type that drives the tractor 1 in various setting states and A vehicle state detecting device 23 including various sensors and switches for detecting an operation state and the like, a positioning unit 24 for measuring a current position p0 and a current direction of the tractor 1, and a vehicle-mounted control unit 40 having various control units. And so on.
The engine 14 may be an electronically controlled gasoline engine having an electronic governor. The power steering unit 16 may be an electric type having an electric motor.

The operating unit 12 includes operating levers such as an accelerator lever and a shift lever, and operating pedals such as an accelerator pedal and a clutch pedal, and a steering wheel 30 for manual steering shown in FIG. A seat 31 and a multi-touch type liquid crystal monitor 32 that enables various information displays and input operations are provided.

As shown in FIG. 2, the transmission unit 15 includes an electronically controlled continuously variable transmission 36 for shifting the power from the engine 14, and the power after shifting by the continuously variable transmission 36 for forward and reverse. And a forward / reverse switching device 37 of an electro-hydraulic control type for switching to the other. The continuously variable transmission 36 includes an I-HMT (Integrated Hydro-static Mechanical Transmission) which is an example of a hydraulic mechanical continuously variable transmission having higher transmission efficiency than a hydrostatic continuously variable transmission (HST). Has been adopted. The forward / reverse switching device 37 includes a hydraulic clutch for connecting / disconnecting forward power, a hydraulic clutch for connecting / disconnecting reverse power, and an electromagnetic valve for controlling the flow of oil to the hydraulic clutch.
Instead of the I-HMT, the continuously variable transmission 36 is an HMT (Hydraulic Mechanical Transmission) which is an example of a hydraulic mechanical continuously variable transmission, a hydrostatic continuously variable transmission, or a belt type continuously variable transmission. An apparatus may be employed. Instead of the continuously variable transmission 36, the transmission unit 15 includes an electro-hydraulic control type stepped transmission having a plurality of shift hydraulic clutches and a plurality of electromagnetic valves for controlling the flow of oil to them. May be included.

Although not shown, the brake unit 17 operates the left and right brakes for individually braking the left and right rear wheels 11 and the left and right brakes in conjunction with the depression of the left and right brake pedals provided in the driving unit 12. A foot brake system, a parking brake system for actuating left and right brakes in conjunction with the operation of a parking lever provided in the driving unit 12, and a brake inside the turn in conjunction with steering of the left and right front wheels 10 at a set angle or more. A swing brake system to be activated is included.

As shown in FIG. 2, the on-vehicle control unit 40 includes an engine control unit 41 for controlling the engine 14, a vehicle speed control unit 42 for controlling the switching of the tractor 1 between the vehicle speed V and forward / backward, and a steering for controlling the steering. A control unit 43, a working device control unit 44 for controlling a working device such as the rotary tillage device 6, a display control unit 45 for controlling display and notification by the liquid crystal monitor 32 and the like, and an automatic traveling control unit 46 for controlling automatic traveling. And a non-volatile in-vehicle storage unit 47 for storing a target route for automatic traveling generated according to the traveling area divided in the work place, and the like. Each of the control units 41 to 46 is configured by an electronic control unit in which a microcontroller and the like are integrated, various control programs, and the like. Each of the control units 41 to 46 is communicably connected via a CAN (Controller Area Network).

The vehicle state detection device 23 is a general term for various sensors and switches provided in each part of the tractor 1. The vehicle state detecting device 23 includes an accelerator sensor for detecting an operating position of an accelerator lever, a first position sensor for shifting for detecting an operating position of a shift lever, and a forward / backward movement for detecting an operating position of a reversing lever for forward / backward switching. A second position sensor for switching, a rotation sensor for detecting the output rotation speed of the engine 14, a vehicle speed sensor for detecting the vehicle speed V of the tractor 1, a steering angle sensor for detecting the steering angle of the front wheels 10, and the like are included. I have.

The engine control unit 41 executes an engine speed maintenance control that maintains the engine speed at a speed corresponding to the operation position of the accelerator lever based on the detection information from the accelerator sensor and the detection information from the rotation sensor. I do.

The vehicle speed control unit 42 performs continuously variable transmission based on the detection information from the first position sensor and the detection information from the vehicle speed sensor so that the vehicle speed V of the tractor 1 is changed to a speed corresponding to the operation position of the shift lever. Vehicle speed control for controlling the operation of the device 36 and forward / reverse switching control for switching the transmission state of the forward / reverse switching device 37 based on the detection information from the second position sensor are executed. The vehicle speed control includes a deceleration stop process for stopping the running of the tractor 1 by controlling the speed of the continuously variable transmission 36 to the zero speed state when the shift lever is operated to the zero speed position.

The positioning unit 24 is a satellite navigation device 25 that measures the current position p0 and the current direction of the tractor 1 using a GPS (Global Positioning System), which is an example of a satellite positioning system (NSS). It has an inertial measurement unit (IMU: Inertial Measurement Unit) 26 that has a gyroscope for the axis, an acceleration sensor in three directions, and measures the attitude and orientation of the tractor 1. Positioning methods using GPS include DGPS (Differential GPS: relative positioning method) and RTK-GPS (Real Time Kinematic GPS: interference positioning method). In the present embodiment, RTK-GPS suitable for positioning of a moving object is adopted. Therefore, as shown in FIG. 1, a reference station 73 that enables positioning by RTK-GPS is installed at a known position around the field.

As shown in FIGS. 1 and 2, the tractor 1 and the reference station 73 each include a

GPS antenna

75, 76 for receiving a radio wave transmitted from a GPS satellite 74 (see FIG. 1), and the tractor 1 and the reference station 73. And

communication modules

77 and 78 that enable wireless communication of each piece of information including positioning information between the two. As a result, the satellite navigation device 25 of the positioning unit 24 uses the positioning information obtained by the GPS antenna 75 on the tractor side receiving the radio waves from the GPS satellites 74 and the GPS antenna 76 on the base station side to transmit the radio waves from the GPS satellites 74. The current position p0 and the current azimuth of the tractor 1 can be measured with high accuracy based on the positioning information obtained by receiving the information. In addition, the positioning unit 24 has the satellite navigation device 25 and the inertial measurement device 26, and measures the current position p0, the current azimuth, and the attitude angle (the yaw angle, the roll angle, and the pitch angle) of the tractor 1 with high accuracy. be able to.

In the tractor 1, the inertial measurement device 26 of the positioning unit 24, the GPS antenna 75, and the communication module 77 are included in the antenna unit 79 shown in FIG. The antenna unit 79 is disposed at the center on the left and right in the upper part on the front side of the cabin 13.

As shown in FIG. 2, the portable communication terminal 3 has a position control between an electronic control unit in which a microcontroller and the like are integrated, a terminal control unit 80 having various control programs, and a communication module 77 on the tractor side. A communication module 90 that enables wireless communication of each piece of information including information is provided. The terminal control unit 80 includes a display control unit 81 that controls the operation of the display unit 4, a target route generation unit 82 that generates a target route P for automatic driving, a target route P generated by the target route generation unit 82, and the like. And a non-volatile terminal storage unit 83 for storing the information. The terminal storage unit 83 stores, as various types of information used for generating the target route P, vehicle body information such as the turning radius R and the working width W1 of the tractor 1 and field information such as the shape and size of the field A. Is stored. The field information includes a plurality of shapes in the field A obtained by using the satellite positioning system when the tractor 1 is moved along the outer periphery of the field A in order to specify the shape and size of the field A. Four corner points Ap1 to Ap4 (see FIG. 10) serving as specific points (shape specifying coordinates), and a shape specifying line for connecting the corner points Ap1 to Ap4 to specify the shape and size of the field A AL (see FIG. 10).

As shown in FIGS. 3 and 4, the target route generation unit 82 determines the turning radius R and the work width W1 of the tractor 1 included in the vehicle body information, and the shape and size of the field A included in the field information. Target route generation control for generating the target route P based on the target route P is performed.
Specifically, as shown in FIG. 3, for example, in a rectangular field A, a start point p1 and an end point p2 of automatic traveling are set, and the work traveling direction of the tractor 1 is a direction along a short side of the field A. 3, the target route generation unit 82 first sets the field A to the margin area A1 adjacent to the outer peripheral edge of the field A, and positions the field A inside the margin area A1. A first partitioning process (step # 1 in FIG. 4) for partitioning into the traveling region A2 to be performed.
Next, based on the turning radius R of the tractor 1, the working width W1, and the like, the target route generation unit 82 adds the working width W1 in the direction along the long side of the field A to the traveling area A2 divided by the first sorting process. A parallel path generation process (step # 2 in FIG. 4) for generating a plurality of parallel paths P1 arranged in parallel at a predetermined interval, and a plurality of parallel paths P1 arranged at the outer edge of each long side in the traveling area A2. Turning path generation processing (step # 3 in FIG. 4) for generating a plurality of turning paths P2 connecting the parallel paths P1 in the running order.
Then, the traveling area A2 divided by the first division processing is set between a pair of non-operation areas A2a set at outer edges of the long sides of the traveling area A2 and an operation set between the pair of non-operation areas A2a. A second partitioning process (step # 4 in FIG. 4) for partitioning into the area A2b is performed, and each of the parallel paths P1 generated in the parallel path generating processing is divided into a non-work path P1a included in the pair of non-work areas A2a. A path segmentation process (step # 5 in FIG. 4) for segmentation into the work route P1b included in the work area A2b is performed.
Thus, the target route generation unit 82 can generate a target route P suitable for automatically driving the tractor 1 in the field A shown in FIG.

In the target route P shown in FIGS. 3, 5, and 7, each non-work route P1a and each turning route P2 are routes on which the tractor 1 automatically travels without performing the tillage work, and each of the above-described work routes P1b is , A route in which the tractor 1 automatically travels while performing the tillage work. The start point p3 of each work path P1b is a work start point at which the tractor 1 starts tillage work, and the end point p4 of each work path P1b is a work stop point at which the tractor 1 stops tillage work. Each of the non-work paths P1a includes a work stop point p4 before the tractor 1 turns on the turning path P2 and a work start point p3 after the tractor 1 turns on the turning path P2. It is an alignment path for aligning in the work traveling direction. Then, the length L1 of each non-work path P1a is determined based on vehicle body information of the tractor 1 including the positional relationship of the rotary tilling device 6 in the tractor 1.
In addition, of the connection points p5 and p6 between the parallel paths P1 and the turning paths P2 on the target path P, the connection point p5 on the end side of each parallel path P1 is the turning start point of the tractor 1, and each of the parallel paths A connection point p6 on the starting end side in P1 is a turning end point of the tractor 1.
Then, the start point p3 and the end point p4 of each work path P1b, the connection points p5 and p6 between the parallel path P1 and each turn path P2 in the target path P, and the length L1 of each non-work path P1a , Etc. are included in the target route P stored in the terminal storage unit 83.

In the field A shown in FIG. 3, FIG. 5, and FIG. 7, when the tractor 1 automatically travels on the outer periphery of the travel area A2, the above-described margin area A1 is formed by the rotary tilling device 6 or the like adjacent to the field A. This is an area secured between the outer peripheral edge of the field A and the traveling area A2 in order to prevent contact with other objects. Then, the distance between the outer periphery of the field A and the traveling area A2 in the margin area A1 is stored in the terminal storage unit 83 as a margin width W2 which is one of the field information.
Each of the non-work areas A2a described above is a ridge turn area for the tractor 1 to turn from the current work path P1b to the next work path P1b when the tractor 1 ridges on the field A. The sum of the length L1 of the non-working path (positioning path) P1a, the turning radius R of the tractor 1, and the half length W1 / 2 of the working width W1 of the tractor 1 is a non-working distance. The ridge turning width W3 between the margin area A1 and the work area A2b in the work area (ridge turning area) A2a, and the ridge turning width W3 is stored in the terminal storage unit 83 as one of the field information. ing.

Note that the target route P shown in FIGS. 3, 5, and 7 is merely an example, and the target route generating unit 82 is configured to output different vehicle body information depending on the model of the tractor 1, the type of work, and the like. Based on field information such as the shape and size of the different fields A, various target paths P suitable for the fields can be generated.

The target route P is stored in the terminal storage unit 83 in a state where the target route P is associated with vehicle body information, field information, and the like, and can be displayed on the display unit 4 of the mobile communication terminal 3. The target route P includes a first vehicle speed V1 (see FIG. 6) set as the target vehicle speed of the tractor 1 in each parallel route P3, and a second vehicle speed V2 (see FIG. 6) set as the target vehicle speed of the tractor 1 in each turning route P2b. 6), the front wheel steering angle in each parallel path P1, the front wheel steering angle in each turning path P2b, and the like.

The terminal control unit 80 transmits the vehicle body information, the field information, the target route P, and the like stored in the terminal storage unit 83 to the vehicle-mounted control unit 40 in response to the transmission request command from the vehicle-mounted control unit 40. The vehicle-mounted control unit 40 stores the received vehicle body information, field information, the target route P, and the like in the vehicle-mounted storage unit 47. Regarding the transmission of the target route P, for example, the terminal control unit 80 transmits all of the target route P from the terminal storage unit 83 to the on-vehicle control unit 40 at a time before the tractor 1 starts the automatic traveling. It may be. Further, for example, the terminal control unit 80 divides the target route P into a plurality of pieces of divided route information for each predetermined distance, and the traveling distance of the tractor 1 reaches the predetermined distance from a stage before the tractor 1 starts automatic traveling. Each time, a predetermined number of divided route information according to the traveling order of the tractor 1 may be sequentially transmitted from the terminal storage unit 83 to the on-vehicle control unit 40.

In the in-vehicle control unit 40, detection information from various sensors and switches included in the vehicle state detection device 23 is input to the automatic traveling control unit 46 via the vehicle speed control unit 42, the steering control unit 43, and the like. ing. Thereby, the automatic traveling control unit 46 can monitor various setting states in the tractor 1 and operation states of the respective units.

In a state where the traveling mode of the tractor 1 is switched to the automatic traveling mode, the automatic traveling control unit 46 starts the automatic traveling by operating the display unit 4 of the mobile communication terminal 3 by a user such as a passenger or a manager outside the vehicle. Is issued, the positioning unit 24 starts the automatic traveling control for automatically traveling the tractor 1 according to the target route P while acquiring the current position p0 and the current direction of the tractor 1.

The automatic cruise control by the automatic cruise control unit 46 includes an automatic cruise control process for transmitting an automatic cruise control command relating to the engine 14 to the engine control unit 41, and a cruise control for automatic cruise control relating to switching of the vehicle speed V of the tractor 1 and forward / backward travel. A vehicle speed automatic control process for transmitting a control command to the vehicle speed control unit 42, a steering automatic control process for transmitting a steering automatic control command to the steering control unit 43, and an automatic operation for a working device such as the rotary tilling device 6. It includes a work automatic control process of transmitting a traveling control command to the work device control unit 44, and the like.

In the automatic control process for the engine, the automatic traveling control unit 46 sends an engine speed change command to instruct the engine control unit 41 to change the engine speed based on the set speed included in the target route P, and the like. Send. The engine control unit 41 executes an engine speed change control for automatically changing the engine speed in response to various control commands for the engine 14 transmitted from the automatic traveling control unit 46.

In the vehicle speed automatic control process, the automatic traveling control unit 46 includes a shift operation command for instructing a shift operation of the continuously variable transmission 36 based on the target vehicle speed included in the target route P, and a shift operation command included in the target route P. A forward / reverse switching command for instructing a forward / backward switching operation of the forward / backward switching device 37 based on the traveling direction of the tractor 1 or the like is transmitted to the vehicle speed control unit 42. The vehicle speed control unit 42 automatically controls the operation of the continuously variable transmission 36 according to various control commands related to the continuously variable transmission 36 and the forward / reverse switching device 37 transmitted from the automatic traveling control unit 46. The control and the automatic forward / reverse switching control for automatically controlling the operation of the forward / backward switching device 37 are executed. In the vehicle speed control, for example, when the target vehicle speed included in the target path P is zero speed, an automatic deceleration stop process for controlling the deceleration of the continuously variable transmission 36 to zero speed and stopping the tractor 1 is stopped. And so on.

In the steering automatic control process, the automatic traveling control unit 46 transmits to the steering control unit 43 a steering command for instructing steering of the left and right front wheels 10 based on the front wheel steering angle and the like included in the target path P. . The steering control unit 43 controls the operation of the power steering unit 16 to steer the left and right front wheels 10 according to the steering command transmitted from the automatic traveling control unit 46, and sets the left and right front wheels 10 When the steering is performed at an angle or more, an automatic brake turning control for operating the brake unit 17 to operate the brake inside the turning is executed.

In the work automatic control process, the automatic traveling control unit 46 performs a work start command for instructing the rotary tilling apparatus 6 to switch to the work state based on the work start point p3 included in the target path P, and a target path. A work stop command for instructing switching of the rotary tillage device 6 to the non-working state based on the work stop point p4 included in P is transmitted to the work device control unit 44. The work device control unit 44 controls the operation of the lifting drive unit 20 and the work clutch unit 19 according to various control commands related to the rotary till device 6 transmitted from the automatic traveling control unit 46, and controls the rotary till device 6 to operate. The automatic work start control that lowers the working height to the operation and the automatic work stop control that stops the rotary tilling device 6 and raises the height to the non-working height are executed. In the working state in which the rotary tilling device 6 is lowered to the working height and operated, the working device control unit 44 raises and lowers the rotary tilling device 6 based on the detection of the tilling depth sensor that detects the tilling depth by the rotary tilling device 6. Automatic tillage depth maintenance control for controlling the operation of the unit 20 to maintain the tillage depth of the rotary tillage device 6 at the set depth, and an inclination sensor for detecting the roll angle of the tractor 1 and an acceleration sensor for the inertial measurement device 26. Based on the detection, an automatic roll angle maintaining control for controlling the operation of the rolling drive unit 21 to maintain the inclined posture in the roll direction of the rotary tilling device 6 at a set posture (for example, a horizontal posture) is executed.

That is, the automatic traveling unit 2 includes the power steering unit 16, the brake unit 17, the work clutch unit 19, the lifting / lowering drive unit 20, the rolling drive unit 21, the vehicle state detection device 23, the positioning unit 24, the on-vehicle control unit 40, And a communication module 77. When these components operate properly, the tractor 1 can be automatically driven with high accuracy in accordance with the target route P, and the rotary tilling device 6 can properly perform tilling.

As shown in FIGS. 2, 5, and 7, when the tractor 1 is automatically traveling on the parallel path P <b> 1 by the automatic traveling control, the automatic traveling control unit 46 starts from the front end of the tractor 1 in the traveling direction of the tractor 1. A separation distance measuring unit 46A for measuring a separation distance D1 to the outer peripheral edge of the field A is provided. The vehicle speed control unit 42 has a vehicle speed limiting unit 42A that limits the vehicle speed V of the tractor 1 according to the separation distance D1 measured by the separation distance measuring unit 46A. The vehicle body information stored in the in-vehicle storage unit 47 includes the front-rear length L2 from the front end of the tractor 1 to the mounting position of the GPS antenna 75 in a plan view of the tractor 1, the relationship between the vehicle speed V of the tractor 1 and the braking distance. And the map shown.

As shown in FIGS. 5 and 7, the separation distance measurement unit 46A includes the current position p0 of the tractor 1 on the parallel path P1 acquired using the satellite positioning system, and the parallel path P1 stored in the in-vehicle storage unit 47. , The turning radius R of the tractor 1, the working width W1 of the tractor 1, the margin width W2 of the field A, and the front-rear length L2 from the front end of the tractor 1 to the mounting position of the GPS antenna 75. And the separation distance D1 is measured based on

Specifically, at a stage before the tractor 1 automatically travels on the parallel path P1 by the automatic traveling control, the separation distance measuring unit 46A determines that the turning radius R of the tractor 1 and half the working width W1 of the tractor 1 By adding W1 / 2 and the margin width W2 of the field A, a fixed separation distance D3 from the terminal point p5 on the parallel path P1 to the outer peripheral edge of the field A is calculated and stored in the in-vehicle storage unit 47. . Then, while the tractor 1 is automatically traveling on the parallel route P1 by the automatic traveling control, the separation distance measuring unit 46A calculates the distance from the current position p0 of the tractor 1 and the connection point p5 on the end side of the parallel route P1. An untraveled distance D4 between them is calculated, and the above-described longitudinal length L2 is subtracted from the sum of the untraveled distance D4 and the fixed clearance D3, thereby measuring the above-mentioned clearance D1.

In other words, the separation distance measuring unit 46A uses the untraveled distance D4 that changes according to the current position p0 of the tractor 1 on the parallel path P1 obtained using the satellite positioning system, and the fixed value stored in the in-vehicle storage unit 47. The separation distance D1 is measured based on the above-mentioned fixed separation distance D3 and the front and rear length L2. Thereby, the calculation load required for measuring the separation distance D1 can be reduced, and as a result, the separation distance D1 can be measured quickly and accurately.

In addition, at the stage where the current position p0 of the tractor 1 in the parallel path P1 is acquired using the satellite positioning system, the separation distance measuring unit 46A sets the front-rear length L2 from the front end of the tractor 1 to the mounting position of the GPS antenna 75. Based on this, it may be configured to correct the deviation between the current position p0 of the tractor 1 and the front end position of the tractor 1.
Further, the separation distance measuring unit 46A determines that the turning radius R of the tractor 1 and the half length W1 / 2 of the working width W1 of the tractor 1 before the tractor 1 automatically runs on the parallel path P1 by the automatic running control. And the fixed distance D3 obtained by adding the margin width W2 of the field A to the fixed distance D3, and subtracting the above-mentioned length L2 from the fixed distance D3 as a fixed value for measuring the distance, and storing it in the vehicle-mounted storage unit 47. You may be comprised so that it may make it. In this case, the calculation load required for measuring the separation distance D1 can be further reduced.

The vehicle speed limiting unit 42A controls the vehicle speed V of the tractor 1 according to the separation distance D1 measured by the separation distance measuring unit 46A while the tractor 1 is automatically running on the parallel path P1 by the automatic running control. Execute

The control operation of the vehicle speed limiting unit 42A in the vehicle speed limiting control will be described with reference to the flowchart shown in FIG. 9. First, as shown in FIG. 7, the vehicle speed limiting unit 42A first determines the separation distance D1 measured by the separation distance measurement unit 46A. , A braking distance calculation process (step # 10 in FIG. 9) for calculating a comparative braking distance D2 shorter than the separation distance D1 by the set distance D5. The calculated relative braking distance D2 is, as shown in FIG. 7, a travel limit at which the current position p0 of the tractor 1 is an intersection between the outer peripheral edge of the field A located in the traveling direction of the tractor 1 and the parallel path P1. The distance becomes shorter as approaching the position p10, and becomes zero when the front end position of the tractor 1 reaches the travel limit position p11 that has entered the field A by the set distance D5 from the travel limit position p10.
Next, the vehicle speed limiting unit 42A sets the vehicle speed V of the tractor 1 according to the comparative braking distance D2 as the upper limit speed Vmax based on the comparative braking distance D2 obtained in the braking distance calculation process and the above-described map. (Step # 11 in FIG. 9) is performed. As shown in FIGS. 6 and 8, the upper limit speed Vmax set here becomes slower as the separation distance D1 becomes shorter with the automatic traveling of the tractor 1 on the parallel path P1, and the front end position of the tractor 1 becomes the traveling limit. When it reaches the position p11 (see FIG. 7), the speed becomes zero.
Further, the vehicle speed limiting unit 42A compares the upper limit speed Vmax set in the upper limit speed setting process with the first vehicle speed V1 which is the target vehicle speed of the tractor 1 in the parallel path P1 (step # 12 in FIG. 9). I do.
Then, as shown in FIG. 6, the braking distance of the tractor 1 corresponding to the first vehicle speed V1 is shorter than the comparative braking distance D2 until the upper limit speed Vmax decreases to the first vehicle speed V1 in the comparison processing. Therefore, the vehicle speed limiting unit 42A performs a first vehicle speed limiting process (step # 13 in FIG. 9) for limiting the vehicle speed V of the tractor 1 so that the vehicle speed V of the tractor 1 is maintained at the first vehicle speed V1.
As shown in FIG. 6, when the upper limit speed Vmax decreases to the first vehicle speed V1 in the comparison process, the braking distance of the tractor 1 corresponding to the first vehicle speed V1 becomes the same as the comparative braking distance D2. The vehicle speed limiting unit 42A performs a second vehicle speed limiting process (a second vehicle speed limiting process that reduces the vehicle speed V of the tractor 1 from the first vehicle speed V1 in accordance with the decrease in the separation distance D1 so that the braking distance of the tractor 1 is maintained at the comparative braking distance D2. Step # 14) of FIG. 9 is performed.
Thereafter, the vehicle speed limiting unit 42A performs a determination process (step # 15 in FIG. 9) to determine whether the tractor 1 has reached the connection point (turning start point) p5 on the end side of the parallel path P1.
Then, the vehicle speed limiting unit 42A continues the second vehicle speed limiting process until it is determined in the determination process that the current position p0 of the tractor 1 has reached the connection point (turning start point) p5.
The vehicle speed limiting unit 42A ends the vehicle speed limiting control when it is determined in the determination process that the current position p0 of the tractor 1 has reached the connection point (turning start point) p5. As a result, the vehicle speed V of the tractor 1, which has been reduced in accordance with the decrease in the separation distance D1 due to the second vehicle speed limiting process, is changed from the current position p0 of the tractor 1 to the connection point (turning start point) p5 as shown in FIG. , The vehicle stops at the vehicle speed corresponding to the separation distance D1 obtained at this time.
When the vehicle speed limiting unit 42A ends the vehicle speed limiting control, the vehicle speed control unit 42 executes the vehicle speed control, and changes the vehicle speed V of the tractor 1 while the tractor 1 is automatically traveling on the turning path P2b. The second vehicle speed V2 (see FIG. 6), which is the target vehicle speed of the tractor 1 on the route P2b, is maintained. Thereafter, as the tractor 1 moves from the turning path P2b to the parallel path P1, the vehicle speed V of the tractor 1 is changed from the second vehicle speed V2 to the first vehicle speed V1, and the vehicle speed control is terminated to stop the vehicle speed control. The vehicle speed limiting control by 42A is executed.

That is, when the tractor 1 starts automatic traveling on the parallel path P1, while the separation distance D1 is long and the braking distance of the tractor 1 according to the first vehicle speed V1 is shorter than the comparison braking distance D2, the vehicle speed limiting unit 42A Performs the first vehicle speed limiting process to limit the vehicle speed V of the tractor 1 to the first vehicle speed V1. As a result, the vehicle speed V of the tractor 1 becomes unnecessarily high, so that the fuel efficiency is deteriorated, and the ability of the tractor 1 to follow the target route P when the tractor 1 automatically travels along the target route P is reduced. Can be avoided.

Thereafter, when the separation distance D1 becomes shorter and the braking distance of the tractor 1 according to the first vehicle speed V1 becomes the same as the comparative braking distance D2, the vehicle speed limiting unit 42A performs the second vehicle speed limiting process, and performs the braking distance of the tractor 1. However, the vehicle speed V of the tractor 1 is limited such that the vehicle speed V is maintained at the comparative braking distance D2 that becomes shorter as the separation distance D1 decreases. Thereby, when the tractor 1 approaches the outer peripheral edge of the field A or reaches the turning path P2, the vehicle speed V of the tractor 1 can be sufficiently reduced. As a result, for example, when the automatic traveling control unit 46 stops traveling of the tractor 1 near the outer peripheral edge of the field A according to the parallel path P1 or turns the tractor 1 according to the turning path P2, It is possible to avoid the possibility of protruding and contacting other objects such as ridges.

As shown in FIG. 1, a tractor 1 includes two lidar sensors (LiDAR Sensor: Light Detection and Range Sensor) which measure a distance to a measurement target in three dimensions using a laser and generate a three-dimensional image. ) 100 and 101 and left and right sonar units 102 for measuring the distance to the measurement object using ultrasonic waves.

Among the front and

rear rider sensors

100 and 101, the front rider sensor 100 looks down the front side of the tractor 1 from an obliquely upper side at the upper left and right center position on the front side of the cabin 13 where the above-described antenna unit 79 is disposed. It is arranged in a forward-lowering position. Thereby, the front rider sensor 100 is set so that the front side of the tractor 1 is the measurement range. The rear rider sensor 101 is arranged at the center of the rear end of the cabin 13 in the upper right and left sides, with the rear side of the tractor 1 looking down diagonally from the upper side in a rearward downward posture. Thus, the rear rider sensor 101 is set such that the rear side of the tractor 1 is the measurement range.

The left and right sonar units 102 are attached to the left and right getting on and off steps disposed below the left and right sides of the cabin 13 in a left and right outward posture having a small depression angle. Accordingly, the left and right sonar units 102 are arranged at a relatively high position between the front wheel 10 and the rear wheel 11 in a state where the left and right outer sides of the tractor 1 are set to be in the measurement range.

The front and

rear rider sensors

100 and 101 and the left and right sonar units 102 are connected to the automatic traveling control unit 46 of the on-vehicle control unit 40 via a CAN so that they can communicate with each other. Thereby, the automatic traveling control unit 46 can monitor the surroundings of the tractor 1 based on information from the front and

rear rider sensors

100 and 101 and the left and right sonar units 102. Accordingly, for example, when the tractor 1 approaches another object such as a ridge adjacent to the field A, or when another object such as another work vehicle approaches the tractor 1, the automatic traveling control unit 46 The situation at that time can be accurately grasped, and vehicle speed control and automatic steering control suitable for the situation at that time can be executed. As a result, the possibility that the tractor 1 contacts another object can be avoided.

[Another embodiment]
Another embodiment of the present invention will be described.
The configuration of each of the different embodiments described below is not limited to being applied independently, and can be applied in combination with the configuration of another alternative embodiment.

(1) Another representative embodiment relating to the configuration of the work vehicle 1 is as follows.
For example, the work vehicle 1 may be configured to have a semi-crawler specification including left and right crawlers instead of the left and right rear wheels 11.
For example, the work vehicle 1 may be configured as a full crawler specification including left and right crawlers in place of the left and right front wheels 10 and the left and right rear wheels 11.
For example, the work vehicle 1 may be configured to have an electric specification including an electric motor instead of the engine 14.
For example, the work vehicle 1 may be configured to have a hybrid specification including the engine 14 and the electric motor.

(2) The separation distance measuring unit 46A determines the current position p0 of the tractor 1 on the parallel path P1 acquired using the satellite positioning system and the work site shape stored in the vehicle-mounted storage unit 47, as shown in FIG. The distance from the current position p0 of the tractor 1 to the shape specifying line AL located on the extension of the parallel path P1 in the traveling direction of the tractor 1 is measured as the separation distance D1 based on the shape specifying line AL for use. It may be configured.

(3) The separation distance measuring unit 46A may be configured to measure the separation distance D1 based on the measurement result of the front rider sensor 100 which is an example of the distance sensor.
Note that a stereo camera or the like may be employed as the distance sensor.

The automatic traveling system for a working vehicle according to the present invention is, for example, a tractor, a riding mower, a riding rice transplanter, a combine, a wheel loader, a snowplow, and other riding working vehicles, and unmanned working vehicles such as unmanned mowers. Can be applied.

Reference Signs List 1 work vehicle 42 vehicle speed control unit 42A vehicle speed limit unit 46 automatic traveling control unit 46A separation distance measurement unit 47 storage unit 100 distance sensor A work place A2 running area Ap1 shape specification point Ap4 shape specification point AL shape specification line D1 separation distance D2 Comparison Braking distance D5 Set distance P Target route P1 Parallel route P2 Turning route R Turning radius V1 Target vehicle speed W Working width W2 Margin width p0 Current position p5 Connection point p6 Connection point

Claims

A vehicle speed control unit that controls the vehicle speed of the work vehicle;
A storage unit for storing a target route generated according to the traveling area divided in the work place,
An automatic travel control unit that automatically travels the work vehicle according to the target route using a satellite positioning system,
The target path includes a plurality of parallel paths arranged in parallel in the traveling area, and a plurality of turning paths arranged at an outer edge of the traveling area and connecting the plurality of parallel paths in the traveling order. Yes,
The automatic traveling control unit is configured to measure a separation distance from the work vehicle to an outer peripheral edge of the work place in a traveling direction of the work vehicle when the work vehicle is automatically traveling on the parallel path. Part
The automatic traveling system for a work vehicle, wherein the vehicle speed control unit includes a vehicle speed limiting unit that limits a vehicle speed of the work vehicle according to the separation distance.
The target route includes a target vehicle speed when the work vehicle automatically travels on the parallel route,
The vehicle speed limiter calculates a comparative braking distance shorter than the separation distance by a set distance, and while the braking distance of the work vehicle according to the target vehicle speed is shorter than the comparative braking distance, the vehicle speed of the work vehicle Performs a first vehicle speed limiting process for limiting the vehicle speed of the work vehicle so that the target vehicle speed is maintained, and when a braking distance of the work vehicle according to the target vehicle speed becomes equal to the comparative braking distance, And performing a second vehicle speed limiting process of reducing a vehicle speed of the work vehicle from the target vehicle speed in accordance with a decrease in the separation distance so that a braking distance of the work vehicle is maintained at the comparative braking distance. An automatic traveling system for a working vehicle as described.
The storage unit includes a turning radius of the work vehicle, a work width of the work vehicle, a margin width set between an outer peripheral edge of the work place and the traveling area, the parallel path, and the turn path. Each connection point with is stored,
The separation distance measurement unit, the current position of the work vehicle in the parallel path obtained using the satellite positioning system, and the connection point on the terminal side in the parallel path stored in the storage unit, The automatic traveling system for a work vehicle according to claim 1 or 2, wherein the separation distance is measured based on a turning radius of the work vehicle, a work width of the work vehicle, and the margin width.
The storage unit stores a plurality of shape specifying points in the work place acquired by using the satellite positioning system, and a shape specifying line that connects the plurality of shape specifying points to specify the shape of the work place. And
The separation distance measurement unit is configured to measure a distance from a current position of the work vehicle on the parallel path acquired using the satellite positioning system to a shape identification line located on an extension of the parallel path in the traveling direction of the work vehicle. The automatic traveling system for a work vehicle according to claim 1 or 2, wherein a distance is measured as the separation distance.
The work vehicle is provided with a distance sensor that measures a distance to a distance measurement target existing in a traveling direction of the work vehicle,
The automatic traveling system for a work vehicle according to claim 1, wherein the separation distance measurement unit measures the separation distance based on a measurement result of the distance sensor.