JP2020178628A - Autonomous travel work vehicle of field - Google Patents

Abstract

To provide an autonomous travel work vehicle contributing to autonomous travel by efficiently making an automatic control device recognize a planar shape of a field.SOLUTION: An autonomous travel work vehicle 1 performs farm work while autonomously traveling in a field by positioning longitudes and latitudes of a starting point S, a first inflection point A and a second inflection point B by going around the field, recognizing a flat surface surrounded by the three points as a first field surface AB, and recognizing a triangle flat surface BC surrounded by the longitude and latitude of a third inflection point C, and a line connecting a starting point A and the second inflection point B. The autonomous travel work vehicle of the field repeats until circling is ended, a work of adding to the first field surface AB when the triangle flat surface BC is not overlapped on the first field surface AB, and subtracting when it is overlapped, and stores a work field area obtained by adding/subtracting the longitudes and latitudes of the starting point S and the respective inflection points A, B... in field data of the automatic control device.SELECTED DRAWING: Figure 6

Description

The present invention relates to an autonomous traveling work vehicle that autonomously travels in a field to perform agricultural work.

As autonomous traveling work vehicles in the field, there are tractors for tilling work, seedling transplanters for transplanting seedlings, and combines for harvesting grains such as rice and wheat.

Patent Document 1 describes a field work vehicle that autonomously travels by outputting a steering signal to a steering actuator of an automatic steering device by a control device based on body position information from a positioning device, and is a field recognition means for detecting a field state. A technique is described in which a steering control signal is output from the control device to the steering actuator based on the field condition detected by the field recognition means so that stable straight running can be performed.

Japanese Unexamined Patent Publication No. 2018-20929

Since the autonomous driving vehicle in the field carries out farm work while traveling straight back and forth in the field, it is necessary to grasp the plane shape of the field, but the field shape is not limited to a rectangle or a square, but is complicated such as a pentagon. In some cases, it is necessary to make the automatic control device recognize the planar shape before starting the work.

An object of the present invention is to make an automatic control device of an autonomous driving vehicle efficiently recognize the planar shape of a field and use it for autonomous driving.

The above-mentioned problem of the present invention is solved by the following technical means.

According to the first aspect of the present invention, in an autonomous driving vehicle that autonomously travels in a field to perform agricultural work, the starting point S, the first turning point A, and the second turning point B are positioned by orbiting the field. The plane surrounded by these three points is recognized as the first field scene AB, and the triangular plane BC surrounded by the longitude and latitude of the third turning point C and the line connecting the starting point A and the second turning point B is recognized, and the triangle is formed. If the plane BC does not overlap with the first field scene AB, the work of adding to the first field scene AB and if it overlaps, the work of subtracting is repeated until the lap is completed, and the process of the starting point S and each song point A, B, ... The work field area obtained by adding or subtracting the degree is stored in the field data 50 of the automatic control device 100, and the work field is autonomously driven in the field.

The invention of claim 2 is to travel on the outer periphery of the field, store the latitude and longitude of each of the curved points A, B, C, ... By the positioning device 60 provided on the traveling vehicle body 2, and calculate the work field area. The self-driving work vehicle in the field according to claim 1, which is a feature.

The invention of claim 3 is characterized in that the drone 47 flies over the field, stores the latitude and longitude of each of the surrounding curved points A, B, C, ..., And calculates the working field area. It is assumed that it is an autonomous traveling work vehicle in the field described in 1.

In the invention of claim 1, the data stored for recognizing the work field is the latitude and longitude and the starting point of the starting point A, the first song point B, the second song point C, and the plurality of song points D, E ... Since the work field area is surrounded by a triangle with A and a plurality of curved points D, E ..., The amount of data is small, the drive load of the automatic control device 100 can be reduced, and efficient autonomous driving can be performed. ..

In the invention of claim 2, in addition to the effect of claim 1, since the traveling vehicle body 2 orbits the field and the positioning device 60 is used to recognize the plane shape and area of the work field, the automatic control system can be simplified. Become.

In the invention of claim 3, in addition to the effect of claim 1, since the working field is recognized by flying the drone 47 over the field, the worker does not need to move the field, and the working field can be recognized. It will be easier.

A side view of a rice transplanter according to an embodiment of the present invention. Same as above Plan view of rice transplanter. Same as above. Top view of the main part of the traveling vehicle body. Same as above The rear view of the main part of the steering wheel of the traveling vehicle body. The block diagram of the automatic control of the same embodiment. The plan view which shows the field recognition method of the said embodiment. The plan view which shows the field recognition method in the drone of the same embodiment. The plan view of setting the automatic traveling path of the same embodiment. The plan view which shows the automatic turning path of the said embodiment.

Hereinafter, embodiments of the present invention will be described with reference to examples shown in the drawings. In the description of the embodiment, the left and right directions are referred to as left and right, respectively, the forward direction is referred to as forward, and the reverse direction is referred to as backward toward the forward direction of the aircraft, but the configuration of the present invention is not limited.

As shown in FIGS. 1 and 2, the passenger-type rice transplanter 1 shown as an embodiment of a work vehicle that autonomously travels in a field has seedlings from a seedling tank 53 via an elevating link device 3 on the rear side of a traveling vehicle body 2. The seedling planting unit 4 for planting seedlings in the field is provided so as to be able to move up and down with a plurality of seedling planting devices 55, ..., And the main body portion of the fertilizer application device 5 is arranged on the upper rear side of the traveling vehicle body 2. ..

First, the main frame 15 constituting the traveling vehicle body 2 will be described.

As shown in FIG. 3, the main frame 15 includes a front beam frame 16 at the front of the fuselage, a rear beam frame 17 at the rear of the fuselage, and a central beam frame between the front and rear beam frames 16 and the rear beam frame 17. 18 is provided, and the front beam frame 16 and the center beam frame 18 are connected by a pair of left and right front side connecting frames 19 and 19, and the center beam frame 18 and the rear side beam frame 17 are connected by a pair of left and right rear side connecting frames 20. Connect at 20.

The front beam frame 16, the center beam frame 18, and the rear beam frame 17 have a longitudinal direction in the left-right direction, and the front connecting frame 19 and the rear connecting frame 20 have a longitudinal direction in the front-rear direction.

The left-right spacing between the left and right front connecting frames 19 and 19 and the rear connecting frames 20 and 20 is substantially the same. Further, the left-right lengths of the central beam frame 18 and the rear beam frame 17 are longer than the left-right lengths of the front beam frame 16. Since the left and right front connecting frames 19 and 19 and the rear connecting frames 20 and 20 are welded at the lower part of the central beam frame 18, the left and right front connecting frames 19 and 19 and the rear connecting frames 20 and 20 are connected. It may be composed of an integral metal square timber.

The driving force is transmitted to the left and right front wheels 10, 10, the rear wheels 11, 11, the working device 4, and the like in the space formed by the front beam frame 16, the center beam frame 18, and the left and right front connecting frames 19, 19. A transmission case 13 and a hydraulic continuously variable transmission (HST) 14 that outputs the driving force supplied from the engine 30 to the transmission case 13 are provided.

Then, the left and right lifting frames 21 and 21 are provided at the rear portion of the rear beam frame 18 at a space narrower than the left and right spacing of the left and right rear connecting frames 20 and 20 so as to project rearward. The rear support frame 22 is attached to the lower part of the upper frames 21 and 21.

Rear wheel transmission cases 11a and 11a for driving the left and right rear wheels 11 and 11 of the traveling vehicle body 2 are provided on both left and right sides of the rear support frame 22, and the elevating link mechanism is provided on the upper portion of the rear support frame 22. The left and right link frames 23, 23 that support 3 are provided so as to face upward.

The elevating link mechanism 3 is provided with a pair of left and right lower link arms 24, 24 on the lower side of the left and right link frames 23, 23 and between the left and right, and an elevating cylinder 25 is provided between the left and right lower link arms 24, 24. And an upper link arm 26 is provided above the elevating cylinder 25. The left and right lower link arms 24 and 24, the elevating cylinder 25, and the upper link arm 26 on the opposite side of the traveling vehicle body 2 are mounted on the front side of the work device 4.

Further, front side transmission cases 10a and 10a that transmit to the left and right front wheels 10 and 10 of the traveling vehicle body 2 are provided on the front side of the left and right end portions of the central beam frame 18 and on the left and right outside of the left and right front side connecting frames 19 and 19, respectively. At the same time, the left and right ends of the central beam frame 18 and the rear beam frame 17 are connected by the left and right extension frames 27 and 27, respectively. The left and right extension frames 27, 27 have a longitudinal direction in the front-rear direction.

Further, a central connecting frame 28 in the front-rear direction is provided below the central beam frame 18, the rear beam frame 17, and the rear support frame 22, and between the front and rear of the central beam frame 18 and the rear beam frame 17, and left and right rear portions. Front and rear support plates 29 and 29 for supporting the engine 30 are provided between the left and right of the connecting frames 20 and 20.

The front and rear support plates 29, 29 are provided with receiving plates 29a, ... For receiving the engine 30 on both the left and right sides of the central connecting frame 28, respectively.

Then, left and right auxiliary frames 31, 31 that pass below the rear beam frame 17 and project rearward are provided on the left and right sides of the front and rear support plates 29, 29, and the rear portions of the left and right auxiliary frames 31, 31 are provided. Are connected by a rear auxiliary frame 32 in the left-right direction. The rear ends of the left and right auxiliary frames 31, 31 are connected to the left and right rear wheel transmission cases 11a, 11a.

As described above, the main frame 15 is configured. Of the main frame 15, the floor on which the operator boardes the front-rear width from the front beam frame 16 to the rear beam frame 17, and the left-right width of the left and right front connection frames 19 and 19 and the rear connection frames 20 and 20. Cover with step 33. The floor tape 33 is integrally formed to improve strength or reduce the number of parts, or is configured to be separable on the front side and the rear side, and on the left side and the right side to facilitate attachment / detachment.

In the above, as shown in FIG. 3, the periphery of the left and right side ends of the central beam frame 18 and the rear beam frame 17 and the left and right extension frames 27 and 27 are not covered by the floor step 33 and are exposed. At this time, the floor step 33 may be expanded to cover the entire main frame 15, but the floor step 33 may be shared among the aircraft having different sizes and the number of planting work rows. The left and right extension steps 34 and 34 are arranged on both the left and right sides of the above.

With the above configuration, since the main frame 15 is configured by connecting a plurality of frame components, the strength is improved as compared with the conventional case.

Further, by arranging the central connecting frame 28 under the front and rear support plates 29 and 29 on which the engine 30 is mounted and connecting the front and rear support plates 29 and 29 with the left and right rear auxiliary frames 32 and 32, a heavy object is used. The engine 30 can be firmly held.

On the front side of the traveling vehicle body 2, as shown in FIGS. 1 and 2, a steering wheel 35 for steering the aircraft, a speed change operating lever 36 for operating the continuously variable transmission 14 and the working device 4, and traveling transmission of the traveling vehicle body 2 are provided. A bonnet 39 is provided at the top, which is provided with an auxiliary shift operation lever 37 for operating an auxiliary shift switching device (not shown) for switching the above and a control panel 38 for operating each part of the machine body. A front cover 40 that can be opened and closed is provided on the front side of the bonnet 39, and inside the front cover 40, a fuel tank, a battery, the left and right front wheels 10 and 10 for steering the steering wheel 35, and left and right front wheel transmission cases. An interlocking mechanism (not shown) that rotates the lower side of 10a and 10a is installed.

Further, in front of the front cover 40, various information such as the working state of the work device 4, the reduction of work materials consumed during the work, and the operation and non-operation of the automatic steering device 205, which will be described later, are displayed by lighting LEDs and the like. A center mascot 70 to be displayed is provided. The center mascot 70 is composed of a work display unit 71 arranged on the lower side and the rear side, and an automatic straight-ahead display unit 72 arranged on the upper side and the front side in a side view.

Then, an engine cover 30a that covers the upper side and the side of the engine 30 is provided on the rear side of the bonnet 39 and above the engine 30, and the work seat 41 on which the worker sits on the engine cover 30a. Is provided.

Further, the fertilizer application device 5 is loaded on the rear side of the work seat 41, specifically on the rear end side of the main frame 15. The driving force of the fertilizer application device 5 is transmitted by the fertilizer application transmission mechanism 5a arranged from the left and right sides of the left and right rear wheel transmission cases 11a toward the fertilizer application device 5.

The front side of the mission case 13 is transmitted to the left and right front wheel transmission cases 10a and 10a (not shown), and the rear part of the mission case 13 is transmitted to the left and right rear wheel transmission cases 11a and 11a. Left and right drive shafts 42, 42 are provided.
Side clutch mechanisms 43, 43 for turning on / off the transmission to the left and right drive shafts 42, 42 are arranged on the side superior to the left and right drive shafts 42, 42 in the transmission direction, and the handle 35 is turned off. When the traveling vehicle body 2 is turned, the side clutch mechanism 43 located inside the turning is turned off, and the transmission to the rear wheels 11 inside the turning is stopped.

As shown in FIG. 3, left and right clutch on / off shafts 44 and 44 are provided in the vertical direction near the left and right centers on the rear side of the mission case 13, and the left and right clutch on / off shafts 44 and 44 are directed toward the outside of the machine body above the left and right clutch on / off shafts 44 and 44. Clutch on / off arms 45 and 45 are provided, respectively. Then, side clutch pedals 43a and 43a for turning on and off the left and right side clutch mechanisms 43 and 43 are provided on the lower front side and one left and right side of the control seat 41.

Further, as shown in FIGS. 1 and 2, below the work device 4, a center float 62C and left and right side floats 62L and 62R that slide in contact with the field scene are provided, and the center float 62C and the left and right sides are provided. A ground leveling rotor 63 for leveling the unevenness of the field scene is provided on the front side of the machine body with respect to the floats 62L and 62R. The driving force to the ground leveling rotor 63 is transmitted by the ground leveling transmission shaft 65 provided in the rear wheel transmission case 11a on one side on the left and right sides. Further, the rear wheel transmission case 11a on one left and right side is provided with a ground leveling clutch 66 for turning on / off the transmission to the ground leveling rotor 63.

The ground leveling rotor 63 is provided with a work detection sensor 209 as a field recognition means. If the water depth of the field is deep or the viscosity of the field is high, the rotation of the leveling rotor 63 will be slow, and if it runs at high speed or the field is rough, the rotation will be fast. Therefore, the state of the field can be determined and the work detection sensor can be used. The detection result of 209 is input to the control device 100 to adjust the steering control signal to the steering actuator 206 of the automatic steering device 205. For example, when the ground leveling rotor 63 rotates quickly, the water depth is shallow, the field scene is hard, and the traveling speed is high, so the steering angle is controlled to be large.

The center float 62C is provided with a rotation potentiometer 64 for detecting the rotation angle of the center float 62C, and it is determined that the depth of the field has changed when the rotation angle of the rotation potentiometer 64 changes by a predetermined angle or more. The control device 100 expands and contracts the elevating cylinder 25 to rotate the elevating link mechanism 3 up and down, so that the vertical height of the work device 4, that is, the work position corresponds to the depth of the field.

This passenger-type rice transplanter is equipped with a so-called automatic straight-ahead system that automatically steers the traveling vehicle body 2 and maintains a straight-ahead traveling state without the help of an operator.

First, the control device 100 is made to recognize the shape and area of the field for automatic steering. For that purpose, as shown in FIG. 6, the rice planting machine 1 is made to go around the inside of the shore of the field, and the starting point S of the corner lot and the first song point A, the second song point B, and the third song point C where the traveling direction changes. ... and the longitude and latitude of each song point are memorized, and the triangular area surrounded by a straight line connecting the starting point S, the first song point A, and the second song point B is memorized as the first field scene AB, and then The area surrounded by the starting point S, the second song point B, and the third song point C is added to the first field scene AB as the second field scene BC, and then the next song point D and the immediately preceding song point C are added. The triangular area surrounded by the starting point S is added, and the lap is completed by returning to the starting point S. In the illustrated example, the fourth field scene DE surrounded by the fourth music point D, the fifth music point E, and the starting point S is included in the third field scene CD, and is therefore subtracted from the work field area.

Further, as a means for recognizing the latitude and longitude of the first turning point A, the second turning point B, the third turning point C, ... Of the work field and the area of the work field, as shown in FIG. 7, the sky above the field. Check the image taken by flying the drone 47 equipped with the tide level device on the monitor 49 of the controller 48, and check the latitude and longitude of the first song point A, the second song point B, the third song point C, and so on. A method of storing in the controller 48, transmitting the field data to the control device 100, calculating by the above-mentioned work field area calculation method, and storing the field data in the field data 50 may also be used.

The traveling target line (teaching path) TL of the rice transplanter 1 is drawn inward by half the width of the machine body from the field outer circumference line HL as shown in FIG. 8, and the turning line is a straight line TL1 and a turning line SL as shown in FIG. By connecting and drawing with the clothoid curve line KL, increasing the engine speed while slowing down, turning at the maximum speed, and heading for the next straight line TL2, it is possible to turn efficiently. In a deformed field such as a pentagon, the line along the longest side is set as the straight running target line line TL.

As shown in FIGS. 1 and 2, the positioning device 60 for detecting the position of the rice transplanter 1 is provided with an antenna frame 201 for mounting a GPS (GNSS) antenna 200 on the traveling vehicle body 2. The antenna frame 201 is a front view of a gate-shaped front frame 201a in which left and right bases are attached to left and right antenna stays 202 and 202 provided on the front side of the main frame 15, and an airframe from the left and right center portions of the front frame 201a. It is composed of a rear frame 201b that faces rearward and faces the left and right central portions on the rear side of the traveling vehicle body 2.

The GPS antenna 200 is mounted near the connection portion between the front frame 201a and the rear frame 201b. The connecting portion between the front frame 201a and the rear frame 201b is near the front and rear of the bonnet 32 and the driver's seat 41, and is near the central portion of the traveling vehicle body 2 in the front-rear direction.

As the GPS antenna 200, it is preferable to use an independent positioning method, a DGPS (relative positioning) method, an RTK (interference positioning) method, or the like, which is suitable for the working area.

When the ground height of the GPS antenna 200 fluctuates due to the influence of the tilt and vibration of the aircraft, the coordinate position different from the actual aircraft position is measured, the reception accuracy deteriorates, and the aircraft travels in a direction deviating from the straight line. Occurs.

In order to prevent this, as shown in FIG. 5, an IMU (Inertial Measurement Unit) 203 is provided in addition to the GPS antenna 200. The IMU 203 was acquired by the GPS antenna 200 based on the difference between the height from the ground surface to the GPS antenna 200 when the traveling vehicle body 2 is in the tilted posture and the height from the ground surface to the GPS antenna 200 when the traveling vehicle body 2 is not tilted. The position coordinates are corrected by the control device 100.

The height from the ground surface to the GPS antenna 200 is determined by measuring the behavior such as the inclination of the traveling vehicle body 2 with the three-axis acceleration sensor and the angular velocity sensor built in the IMU 203.

In addition to this, the directional sensor 204 is provided so that the control device 100 can more reliably determine whether or not the traveling direction of the aircraft by the automatic straight-ahead system is correct.

The position information acquired by the GPS antenna 200 is corrected by the control device 100 based on the information detected by the IMU 203 and the directional sensor 204. Then, the control device 100 compares the current position information with the previously acquired position information, and if the difference in the position information exceeds the permissible range, the left and right front wheels 10 in order to return the aircraft to the straight traveling position. , 10 are steered in the left-right direction.

An automatic steering device 205 for rotating the steering wheel 35 with a steering actuator 206 is provided in order to automate the steering of the left and right front wheels 10 and 10 or the turning of a crawler or the like. In the automatic steering device 205, the operating amount of the steering actuator 206 fluctuates based on the difference between the X coordinate of the current position information calculated by the control device 100 and the X coordinate of the reference position information previously acquired. By doing so, the steering wheel 35 is turned to the left and right in order to direct the aircraft to the straight traveling position, and when the straight traveling position is reached, the steering actuator 206 is stopped to stop the automatic steering of the steering wheel 35. The rudder actuator 206 is composed of an electric or hydraulic motor or a cylinder.

A radio wave detection device 102 for detecting radio waves from the GPS antenna 200 is provided, and when the received radio wave is lower than a predetermined value, the traveling speed is lowered and the steering angle control to the steering actuator 206 is reduced for work. For safety. When the received radio wave is restored to a predetermined value, the traveling speed and the steering angle control to the steering actuator 206 are restored.

With the above configuration, the handle 35 is automatically steered according to the difference in the X coordinates of the calculated position information, and the machine body can be automatically adjusted to the straight running position, so that the work position by the work device 4 is in the left-right direction. It is prevented from shifting, and it is less likely that there will be places in the field where work is not performed. As a result, it is not necessary to manually perform the work later in the place where the work was not performed, and the labor of the worker is reduced.

As shown in FIG. 4, a finger up lever that can be operated in the vertical direction is attached as the automatic straight-ahead setting member 207, but a toggle switch, a push switch, a joystick, or the like may be used.

In FIG. 1, a depth sensor 103 composed of an ultrasonic sensor is attached to the traveling vehicle body 2 in front of the front wheel 10 toward the field scene to detect the distance to the water storage surface, and the front wheel 10 detects the fertility of the field. An energization sensor 104 is provided to detect the fertility of the field, or a temperature sensor 105 is provided on the traveling vehicle body 2 to detect the outside air temperature, and each of them is displayed on the control panel 38 by the operator. Make it easier to recognize the condition of the field. Further, when the temperature sensor 105 detects an abnormally low temperature, it determines that there is no water in the field and weakens the control output to the steering actuator 206, and when the detection value of the energization sensor 104 is high, it determines that the field is soft and the steering actuator. 206 edition Increases the control output.

Although not shown, if an LED lamp that displays the external contour of the traveling vehicle body 2 is provided and turned on at night or in the presence of fog, the working position of the rice transplanter 1 becomes clear to the workers around it, which is safe. is there.

In addition, a fisheye camera that captures the seedling planting portion 4 is provided to display it on the monitor of the control panel 38, and a proximity sensor is provided at the peripheral corner portion of the seedling planting portion 4 to issue an alarm when an obstacle is detected. Then it is good.

S Departure point A 1st song point B 2nd song point 3rd song point C
AB 1st field scene BC Triangular plane CD Triangular plane DE Triangular plane 2 Traveling vehicle body 47 Drone 50 Field data 60 Positioning device 100 Automatic control device

Claims (3)

In an autonomous driving vehicle that autonomously travels in the field to perform agricultural work, the latitude and longitude of the starting point (S), the first turning point (A), and the second turning point (B) are determined by orbiting the field. The plane surrounded by three points is recognized as the first field scene (AB), and the triangular plane surrounded by the latitude and longitude of the third turning point (C) and the line connecting the starting point (A) and the second turning point (B). Recognizing (BC), if the triangular plane (BC) does not overlap with the first field scene (AB), it is added to the first field scene (AB), and if it overlaps, the work of subtracting is completed. The starting point (S), the latitude and longitude of each of the curved points (A), (B), ..., And the added / subtracted work field area are stored in the field data (50) of the automatic control device (100). An autonomous driving vehicle in the field, which is characterized by this. The working field area is stored by storing the latitude and longitude of each of the curved points (A), (B), (C), ... By the positioning device (60) provided on the traveling vehicle body (2) while traveling on the outer circumference of the field. The field autonomous traveling work vehicle according to claim 1, wherein the calculation is performed. It is characterized in that the drone (47) flies over the field, stores the latitude and longitude of each of the surrounding curved points (A), (B), (C), ..., And calculates the working field area. The field autonomous traveling work vehicle according to claim 1.