JP2023098881A5 - - Google Patents

Description

The present invention relates to work vehicles, such as robotic agricultural tractors.

A pair of left and right obstacle sensors are installed in the front of the vehicle, which detects the driving route and autonomously travels while controlling the steering. When the obstacle sensors detect an obstacle, the vehicle is brought to an emergency stop. 2. Description of the Related Art In a work vehicle provided with a control unit, there is known a work vehicle that rotates an obstacle sensor so as to turn substantially in a turning direction according to the magnitude of a steering angle (see, for example, Patent Document 1).

JP-A-6-189610

However, the obstacle sensor may erroneously detect the water surface or the ground as an obstacle when the vehicle body tilts to the left or right, or when the vehicle body sinks while traveling in a field filled with water such as puddling. there were.

In consideration of such problems of conventional work vehicles, the present invention provides a work vehicle that can work efficiently by appropriately changing the detection range of an obstacle detection sensor in order to eliminate such erroneous detection. for the purpose.

A first aspect of the present invention is
In a working vehicle with a working machine attached to the rear part of the vehicle body,
A pair of left and right front ultrasonic sensors for detecting a range wider than the width of the vehicle body on the front side of the vehicle body are provided in front of the vehicle body,
A left ultrasonic sensor that detects the range on the left side of the vehicle body and a right ultrasonic sensor that detects the range on the right side of the vehicle body are provided on the side of the vehicle body,
An obstacle sensor is provided at the rear of the vehicle body to detect the rear of the vehicle body,
Depending on the lateral width of the working machine. The work vehicle includes work implement width input means for changing the detection range of the obstacle sensor .

According to the first aspect of the present invention, it is possible to prevent the work machine 11 from being detected as an obstacle .

A second aspect of the present invention is
A work machine is attached to the work vehicle,
a lift arm for lifting and lowering the working machine;
a height sensor that detects the height of the working machine relative to the working vehicle;
a tillage depth sensor that detects the tillage depth of the working machine;
The controller calculates the amount of subsidence of the work vehicle with respect to the ground based on the detection value of the height sensor and the detection value of the plowing depth sensor, and detects the obstacle of the obstacle detection mechanism according to the subsidence amount. 1 is a work vehicle of the first invention that changes the detection range;

According to the second aspect of the present invention, when the vehicle body is sinking, the distance between the obstacle sensor and the ground becomes closer. Therefore, by changing the obstacle determination range, it is possible to determine that the ground is an obstacle and stop the vehicle. Since it can be suppressed, it can work efficiently.

A third aspect of the present invention is
The obstacle detection mechanism has a plurality of obstacle detection sensors,
The controller is
An obstacle detection mode for detecting obstacles during automatic operation using the obstacle detection mechanism, and a subsidence amount for measuring the amount of subsidence of the work vehicle with respect to the ground using all or part of the obstacle detection sensor. and a measurement mode, wherein the obstacle detection range of the obstacle detection mechanism in the obstacle detection mode is changed according to the amount of subsidence.

According to the third aspect of the present invention, since the obstacle sensor is also used for measuring the amount of subsidence, it is possible to directly measure the amount of subsidence of the vehicle at low cost.

The fourth aspect of the present invention is
The work vehicle according to the third aspect of the present invention, wherein the controller sets the obstacle detection range in the subsidence measurement mode to be wider than the obstacle detection range in the obstacle detection mode.

According to the fourth aspect of the present invention, even if an obstacle sensor is also used to measure the amount of subsidence, the amount of subsidence can be measured more accurately.

According to the present invention, an obstacle can be detected properly even if the vehicle tilts or sinks, so it is possible to provide a work vehicle that can appropriately and automatically travel.

1 is a left side view of an agricultural robot tractor according to an embodiment of the present invention; FIG. 1 is a plan view of an agricultural robot tractor according to an embodiment of the present invention; FIG. FIG. 1 is an explanatory diagram of a traveling route of an agricultural robot tractor according to an embodiment of the present invention; 1 is a configuration diagram of a control system of an agricultural robot tractor according to an embodiment of the present invention; FIG. 1 is a block diagram centering on a controller of an agricultural robot tractor according to an embodiment of the present invention; FIG. FIG. 2 is a plan view showing a state using an infrared sensor for detecting the front and rear of the agricultural robot tractor according to the embodiment of the present invention; FIG. 1 is a rear view showing an inclined state of an agricultural robot tractor according to an embodiment of the present invention; FIG. 2 is a plan view for explaining the obstacle detection range of the agricultural robot tractor according to the embodiment of the present invention; FIG. 2 is a plan view for explaining the relationship between the width of the working machine of the agricultural robot tractor and the obstacle detection range according to the embodiment of the present invention; FIG. 2 is a left side view for explaining the measurement of the subsidence amount of the agricultural robot tractor according to the embodiment of the present invention; FIG. 4 is a left side view for explaining the relationship between the settlement amount and the obstacle detection range of the agricultural robot tractor according to the embodiment of the present invention;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

First, referring to FIGS. 1 to 4, the configuration and operation of an agricultural robot tractor according to the present embodiment, which is an example of a work vehicle according to the present invention, will be specifically described.

1 is a left side view of the agricultural robot tractor according to the embodiment of the invention, and FIG. 2 is a plan view of the agricultural robot tractor according to the embodiment of the invention. FIG. 3 is a schematic plan view showing how the agricultural robot tractor of the embodiment of the present invention automatically travels in a field. FIG. 4 is an explanatory diagram of the control system of the agricultural robot tractor according to the embodiment of the present invention.

First, the basic configuration and operation of the agricultural robot tractor of this embodiment will be described. The configuration, operation, and the like related to controller 200 will be described later in detail.

An engine 30 is provided inside a bonnet 31 at the front of the vehicle body 10 . Rotational power of engine 30 is transmitted through various clutches inside a transmission case provided below floor 21 of operating unit 20 . More specifically, the rotational power changed by the main transmission and the sub-transmission is transmitted to the left front wheel 40L and the right front wheel 40R and the left rear wheel 50L and the right rear wheel 50R.

A brake pedal disconnection pedal and a clutch pedal are arranged on the left floor 21 . A left brake pedal, a right brake pedal, and an accelerator pedal are arranged on the right floor 21 . A work implement 11 is attached to the rear portion of the vehicle body 10 using, for example, a three-point link mechanism.

In FIG. 4, the controller 200 has a tillage machine lift control section, an engine control section, and a travel control section that operate in cooperation with a memory, a timer, and the like. FIG. 3 is an explanatory diagram of the traveling route C of the agricultural robot tractor according to the embodiment of the present invention.

The controller 200 performs automatic travel control for causing the vehicle body 10 to travel along a preset travel route C based on the settings of the agricultural robot tractor and the working machine 11, instructions from the remote controller 201, and GNSS (Global Navigation Satellite System). system) signal, the obstacle detection result of the obstacle detection mechanism 600, and the like.

The vehicle body position measuring mechanism 500 is a mechanism that measures the position of the vehicle body 10 . In this embodiment, vehicle body position measurement mechanism 500 has a GNSS unit. 110 is a forward/reverse clutch, 120 is a main transmission, 130 is an auxiliary transmission, 201 is a remote controller, 320 is a 4WD clutch, 330 is a steering cylinder, 350 is a vehicle speed sensor, 400L is a left brake device, and 400R is a right brake. It is a device.

In this embodiment, the obstacle detection mechanism 600 has two front ultrasonic sensors 610, three left ultrasonic sensors 620L and three right ultrasonic sensors 620R. These are examples of the obstacle detection sensor of the present invention.

The front ultrasonic sensor 610 has a detection range A1 on the front side of the vehicle body 10, the left ultrasonic sensor 620L has a detection range A2L on the left side of the vehicle body 10, and the right ultrasonic sensor 620R has a detection range A2L on the left side of the vehicle body 10. It is a sensor whose detection range A2R is the range on the right side of the vehicle body 10 .

Based on the return time of the ultrasonic wave reflected by the obstacle, the presence of obstacles in the detection range A1 of the front ultrasonic sensor 610, the detection range A2L of the left ultrasonic sensor 620L, and the detection range A2R of the right ultrasonic sensor 620R. is recognized, the vehicle body 10 is automatically stopped. For this reason, a predetermined threshold is set for the return time, and if the reflected signal returns within that time, the presence of the obstacle is recognized. The range is modeled in the drawing.

FIG. 6 is a plan view of an agricultural robot tractor of a modified embodiment of the present invention. As shown in FIG. 6, the obstacle detection mechanism 600 includes one front infrared sensor 630 and one It has a rear infrared sensor 640 .

Here, the front infrared sensor 630 is a sensor whose detection range A3 is the front side range of the vehicle body 10, and the rear infrared sensor 640 is a sensor whose detection range A4 is the rear side range of the vehicle body 10. FIG.

When the presence of an obstacle in the detection range A3 of the front infrared sensor 630 and the detection range A4 of the rear infrared sensor 640 is recognized based on the return time of the infrared rays reflected by the obstacle, the vehicle body 10 automatically stops. is done.

Of course, in the embodiment of the present invention, the obstacle detection mechanism 600 may detect front, rear, left, and right with one omnidirectional type ultrasonic sensor attached to the vehicle body roof.

Next, with reference to FIGS. 7 to 11, the configuration and operation of the agricultural robot tractor according to this embodiment and another embodiment will be described more specifically.

FIG. 7 is a schematic rear view showing a state in which the vehicle body 10 according to the present embodiment is tilted in a field. In the case of the figure, it is in a state of being tilted to the left. Here, as described above, the detection range A1 of the front ultrasonic sensor 610, the detection range A2L of the left ultrasonic sensor 620L, and the detection range A2R of the right ultrasonic sensor 620R are shown from the rear side.

100 indicates the ground of the field, and 101 indicates a state where the field is partially raised. Here, it is assumed that the right rear wheel 50R runs over the raised portion 101 while the vehicle body 10 is running.

Therefore, the vehicle body 10 leans to the left. The tilt sensor 340 detects the tilt. As shown in FIG. 4, the output signal of the tilt sensor 340 is input to the controller 200 . The controller 200 receives the tilt signal from the tilt sensor 340 and instructs the obstacle detection mechanism 600 to change the detection ranges A2L and A2R.

As shown in FIG. 7, each detection range A2L on the left side is made narrower than each corresponding detection range A2R on the right side. That is, as shown in the figure, when the vehicle body 10 tilts to the left, if the left side detection range A2L is set to the same size as before, when the tilt is large, the existence of the ground 100 causes an obstacle to be detected. There is a risk of outputting a detection signal even though it does not exist.

However, as shown in FIG. 7, the left detection range A2L is narrower than when it is not tilted, so there is concern that the left detection range A2L may erroneously detect the ground 100 as an obstacle. There is no Therefore, there is no concern that the vehicle body 10 will stop each time due to an erroneous detection and work efficiency will drop. As a result, since the detection range on the non-tilted side is not changed, the detection range on the tilted side is changed to be narrower than the detection range on the non-tilted side.

As described above, the degree of change in the detection range is related to the degree of tilt, so it is desirable that the degree of change in the detection range is also proportional to the degree of tilt of the vehicle body 10 . That is, when the slope is gentle, the degree of narrowing is moderate, and when the slope is steep, the degree of narrowing is also increased.

FIG. 8 is a schematic plan view of the tractor of this embodiment, showing a detection range A2L' in which the detection range A2L is narrowed and a detection range A2R' in which the detection range A2R is narrowed. M and N are codes indicating the narrowing situation.

It is desirable that not only the tilt of the vehicle body 10 is detected, but also the angular velocity of the tilt related to the tilt is detected and used. This is because a response delay may occur in the detection of the tilt sensor 340, and in such a case, even though the tilt has begun, the detection range may not be narrowed and erroneous detection may occur. can be avoided.

FIG. 5 is a block diagram mainly showing the configuration of the controller 200. As shown in FIG. Reference numeral 201 denotes reference time means for determining the detection range, and 202 denotes obstacle determination means for receiving signals from the plurality of ultrasonic sensors 610 of the obstacle detection mechanism 600 and determining the presence of obstacles.

Reference numeral 203 denotes means for receiving a signal from a sensor such as the tilt sensor 340 and changing the reference time of the reference time means 201, that is, changing the detection range.

FIG. 9 shows another embodiment of the present invention, showing a case where the detection range is changed according to the lateral width of a working machine 11 mounted behind the vehicle body 10, for example, a cultivator. The detection range A2R narrows to A2R' and the detection range A2L narrows to A2L'. In FIG. 4, 202 is working machine width input means for inputting the width P of the working machine 11 .

That is, when the width P of the work implement 11 is large as in the case of FIG. 9, the work implement 11 may be detected as an obstacle depending on the setting of the detection range. Therefore, when the width P of the work implement 11 is large, it is desirable to narrow the detection range or change the direction of the detection range according to the extent. Of course, if the width of the working machine 11 is small, it is possible to widen the detection range.

Another embodiment will be described. As described above, in FIG. 6, obstacle detection mechanism 600 has one front infrared sensor 630 and one rear infrared sensor 640 . Here, the front infrared sensor 630 is a sensor whose detection range A3 is the front range of the vehicle body 10, and the rear infrared sensor 640 is a sensor whose detection range A4 is the rear range of the vehicle body 10. FIG.

By the way, the vehicle body 10 as described above may tilt in the front-rear direction (pitching) rather than in the left-right direction (rolling).

The infrared sensors 630 and 640 may erroneously detect the presence of the ground 100 as an obstacle as described above unless the detection range is changed even when there is such an inclination in the front-rear direction.

Therefore, the tilt sensor 340 also detects the tilt in the longitudinal direction, and changes the detection range of the infrared sensors 630 and 640 . The way of changing is to change the right and left range, the front and back range, and the elevation range to ranges and directions that do not cause erroneous detection according to the degree and direction of the inclination.

The tilt sensor 340 for detecting rolling and pitching described above may be of a type that utilizes the detection values of an IMU (inertial measurement unit) integrated with the GNSS antenna, in addition to sensors of ordinary devices. Cost savings.

FIG. 10 is a side view showing another embodiment of the tractor of the present invention; Here, in the above-described case, the obstacle detection range is changed according to the inclination of the vehicle body 10, whether it is rolling or pitching. The obstacle detection range is changed correspondingly.

That is, although there are various methods for measuring the amount of subsidence of the vehicle body 10, a rotary, which is an example of the working machine 11, is used in the present embodiment. 10, 11a is a lift arm that holds the work machine 11, 11b is a position sensor that detects the position of the lift arm 11a, 11c is a rear cover of the work machine 11, and 11d is a sensor that detects the angle of the rear cover 11c. . These position sensor 11b and angle sensor 11d are examples of the subsidence sensor 12 in FIG.

The controller 200 measures the amount of subsidence of the rear wheels 50L, 50R with respect to the ground 100 based on the signals from these sensors 11b, 11d. That is, when the rear cover 11c is raised and the lift arm 11a is also raised, it is determined that the vehicle is sinking, and the amount of sinking can also be measured.

The position sensor 11b is an example of a height sensor of the present invention, and the angle sensor 11d is an example of a plowing depth sensor for detecting plowing depth of the present invention.

FIG. 11 is a side view for explaining the situation, in which the infrared detection range A3 is narrowed to A3' when it is sunk. In the normal detection range A3, if the ground 100 is sunk, there is a risk of erroneously detecting the ground 100 as an obstacle.

Furthermore, it is also desirable to change the extent to which the detection range A3 is narrowed in proportion to the amount of subsidence. If the amount of subsidence is too large and the detection range A3 is too small, the vehicle body 10 is stopped. If the detection range A3 is too narrow, the capability of erroneous detection will be too low, so this is to be prevented.

Next, in FIG. 10, 12a is a dedicated ultrasonic sensor for measuring the distance to the ground 100, which is attached to the front side of the vehicle body 10 and emits ultrasonic waves toward the ground 100 to measure the distance. . Since the position of the front attachment is known in advance, the amount of wheel subsidence can be measured. The controller 200 changes the detection range according to the amount of subsidence measured by the ultrasonic sensor 12a. This ultrasonic sensor 12a is also an example of the subsidence sensor 12 described above.

As a further modified example, instead of providing a special ultrasonic sensor for measuring the distance to the ground 100, a part of the sensors such as the ultrasonic sensor 610 described above can also be used.

In the case of such a modification, the mode for measuring the amount of wheel subsidence and the mode for detecting obstacles are separated. It is desirable to set the detection range wider than the detection range in the case of the mode to be set (this method can be done by changing the reference time as explained with reference to FIG. 5).

Such widening makes it possible to reliably read reflected waves from the ground 100 . If the degree of subsidence is large, it can be detected by the fact that the reflected wave returns in a short period of time.

Furthermore, it is desirable to execute the mode for measuring the amount of subsidence before starting work on the vehicle body 10 . After starting work, switch to obstacle detection mode and execute. Since the amount of wheel settling does not change much in one field, it is sufficient to measure it once before starting work.

In addition, the program of the invention related to the present invention is a program for causing a computer to execute all or part of the operation of the automatic cruise control method of the invention related to the present invention described above, cooperating with the computer. It is a program that works with

In addition, one usage form of the program of the invention related to the present invention is a form in which it is transmitted in a transmission medium such as the Internet, light, radio waves or sound waves, read by a computer, and operates in cooperation with the computer. may be

In addition, the computer is not limited to pure hardware such as a CPU (Central Processing Unit), but may also include firmware, an OS (Operating System), and peripheral devices.

It should be noted that, as described above, the configuration of the present invention may be implemented in software or in hardware.

INDUSTRIAL APPLICABILITY The work vehicle of the present invention can achieve smooth automatic travel control even when it is tilted or subsided, and is useful for the purpose of being used as a work vehicle such as an agricultural robot tractor, for example.

10 Vehicle body 11 Work implement 12 Subsidence sensor 20 Driving unit 21 Floor 30 Engine 31 Bonnet 40L Front left wheel 40R Front right wheel 50L Rear left wheel 50R Rear right wheel 110 Forward/reverse clutch 120 Main transmission 130 Subtransmission 200 Controller 201 Remote controller 320 4WD Clutch 330 Steering Cylinder 340 Inclination Sensor 350 Vehicle Speed Sensor 400L Left Braking Device 400R Right Braking Device 500 Body Position Measuring Mechanism 600 Obstacle Detecting Mechanism 601 Multilayer Light 610 Front Ultrasonic Sensor 620L Left Ultrasonic Sensor 620R Right Ultrasonic Sensor 630 Front Infrared Sensor 640 Rear infrared sensor A, A1, A2L, A2R, A3, A4 Detection range C Driving route

Claims (4)

In a working vehicle with a working machine attached to the rear part of the vehicle body,
A pair of left and right front ultrasonic sensors for detecting a range wider than the width of the vehicle body on the front side of the vehicle body are provided in front of the vehicle body,
A left ultrasonic sensor that detects the range on the left side of the vehicle body and a right ultrasonic sensor that detects the range on the right side of the vehicle body are provided on the side of the vehicle body,
An obstacle sensor is provided at the rear of the vehicle body to detect the rear of the vehicle body,
Depending on the lateral width of the working machine. A work vehicle comprising work machine width input means for changing a detection range of the obstacle sensor . A work machine is attached to the work vehicle,
a lift arm for lifting and lowering the working machine;
a height sensor that detects the height of the working machine relative to the working vehicle;
a tillage depth sensor that detects the tillage depth of the working machine;
The controller calculates the amount of subsidence of the work vehicle with respect to the ground based on the detection value of the height sensor and the detection value of the plowing depth sensor, and detects the obstacle of the obstacle detection mechanism according to the subsidence amount. The work vehicle according to claim 1, wherein the detection range is changed. The obstacle detection mechanism has a plurality of obstacle detection sensors,
The controller is
An obstacle detection mode for detecting obstacles during automatic operation using the obstacle detection mechanism, and a subsidence amount for measuring the amount of subsidence of the work vehicle with respect to the ground using all or part of the obstacle detection sensor. 2. The work vehicle according to claim 1, further comprising a measurement mode, wherein an obstacle detection range of said obstacle detection mechanism in said obstacle detection mode is changed according to said subsidence amount. 4. The work vehicle according to claim 3, wherein said controller sets said obstacle detection range in said subsidence measurement mode to be wider than said obstacle detection range in said obstacle detection mode.