JPH0259681B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a steering control device for an autonomous working vehicle such as a self-propelled combine harvester or an automatic lawn mowing vehicle. A tracing sensor detects the amount of lateral deviation of the aircraft body equipped with a traveling device with respect to the traveling guideline, and the aircraft automatically travels along the guideline based on the detected deviation amount detected by the tracing sensor. In order to achieve this, the device is provided with a steering control means for steering the pair of crawler traveling devices by controlling the opening and closing of a pair of clutches that individually turn on and off the drive of the pair of crawler traveling devices, and the steering control means adjusts the amount of deviation to the detected deviation amount. The present invention relates to a steering control device for an automatic traveling work vehicle, which is configured to disengage the clutch of the crawler traveling device on the turning direction side for a set clutch disengagement time upon determining that steering is necessary based on the above. .

[Conventional technology]

When the above-mentioned steering control device is applied to a self-propelled combine harvester, for example, the machine is operated so that the machine follows the rows of grain culms planted in the field as a traveling guideline. direction control.

Conventionally, the clutch disengagement time was maintained constant.

[Problem to be solved by the invention]

The ground conditions on which the above-mentioned work vehicle travels will change due to wetlands, uneven terrain, etc. Along with this, the slip rate of the crawler traveling device changes, etc., so that the turning angle when the clutch of the crawler traveling device on the turning side is disengaged with a fixed clutch disengagement time, that is, the angle of change of direction of the aircraft, changes. Changes in size.

By the way, as shown in FIG. 3, for example, when the combine harvester is run along a straight grain culm row H as a running guideline, once the machine body V is steered to the left, it is then steered to the right. You need to steer to. In other words, in order to automatically run an aircraft equipped with a pair of left and right crawler traveling devices along a traveling guideline, in the case of a type in which the clutch of the crawler traveling device on the side in the turning direction is disengaged during steering, the leftward operation is required. The process of steering to the right will be repeated.

Repeating left and right steering in this way is undesirable in terms of ride comfort for the occupants and energy required for steering, and it is desirable to reduce the frequency of steering as much as possible.

In order to reduce the frequency of steering as much as possible, the angle at which the aircraft changes direction when the clutch is disengaged during a single maneuver, that is, when the clutch is disengaged within the set clutch disengagement time, must be adjusted so that the aircraft moves along the traveling guideline. It is necessary to get the angle as close as possible to the minimum angle required to achieve this.

If the ground conditions are constant, the angle at which the aircraft's direction is changed by one maneuver can be preset to the optimal angle. In other words, it is possible to perform good steering even if the time during which the drive of either the left or right crawler traveling device is stopped during one steering operation, that is, the clutch disengagement time, is set to a constant value in advance. However, as the ground conditions change as described above, maintaining the clutch disengagement time constant as in the past may lead to the inconvenience of increasing the frequency of steering depending on the ground conditions. Improvement is desired.

The present invention has been made in view of the above-mentioned circumstances, and its purpose is to reduce the frequency of steering regardless of changes in ground conditions.

[Means to solve the problem]

The steering control device for an automatic traveling work vehicle according to the present invention includes a tracing sensor that detects the amount of lateral deviation of an aircraft body equipped with a pair of left and right crawler traveling devices with respect to a traveling guideline; Steering control means for steering the aircraft by controlling the opening and closing of a pair of clutches that individually turn on and off the drive of the pair of crawler traveling devices, based on the detected deviation amount, in order to automatically travel the aircraft along the guideline. and the steering control means, upon determining that steering is necessary based on the detected deviation amount, engages the clutch of the crawler traveling device on the turning direction side at a set clutch disengagement time. It is configured to perform a steering operation, and its characteristic configuration is based on the detection result of the steering frequency in order to reduce the frequency of steering to make the aircraft follow the traveling guideline. The present invention is provided with a steering control amount correction means for automatically correcting the clutch disengagement time, and its effects are as follows.

[Effect]

In other words, for example, the steering frequency is detected based on the distance traveled by the aircraft from one steering to the next steering, and the steering frequency is determined based on the detection result of the steering frequency. The clutch disengagement time is corrected so that it is reduced.

〔Effect of the invention〕

Therefore, it is possible to correct the clutch disengagement time according to the ground conditions and prevent the frequency of steering from increasing, which improves passenger comfort and reduces the energy required for steering regardless of the ground conditions. As a result, a steering control device for an automatic traveling work vehicle that can be used even better has been obtained.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

As shown in FIGS. 1 and 2, a reaping section 2 that raises and reaps the planted grain culms in the field, and while transporting the reaped grain culms, changes its posture to a sideways posture and transfers them to the feed chain 1; A threshing device 3 for selectively collecting grains by threshing the grain culms held and conveyed by the feed chain 1 is mounted on a machine body V equipped with a pair of left and right crawler traveling devices 4, and the machine can be used as a work vehicle. A combine has been configured.

The lower part of the reaping part 2 is provided by contacting the base of the grain culm introduced into the reaping part 2 from the front.
A stock sensor _S0 configured as a contact switch that outputs an ON/OFF signal is provided to detect the start and stop of the reaping operation.

Further, a weeding tool 6 provided at the tip of the cutting section 2
Mounting frame 7 for weeding tools 6a and 6b on both left and right ends of
, a sensor bar 8 is biased toward the front side of the machine V, contacts the grain culm introduced into the reaping section 2, and rotates toward the rear side of the machine V by an angle corresponding to the contact position.
and a potentiometer _R for detecting the rotation angle of the sensor bar ₈ , respectively. The amount of lateral deviation r of the body V with respect to the grain culm row H is detected.

To explain the detected deviation amount r of the left and right scanning sensors S ₁ and S ₂ , as shown in FIG. The detection is divided into a, b, and c.

That is, a shallow scanning zone is defined as a state in which the sensor bar 8 is shifted away from the grain culm row H from a state in which the sensor bar 8 returns to the front side of the machine body V to a state in which it rotates backward by a predetermined angle. A is defined as a dead zone b, which is along the grain culm row up to a state in which the grain is rotated further rearward by a predetermined angle than this shallow tracing zone a, and a state in which the grain is rotated further rearward than this dead zone zone b is defined as a dead zone b. Deep tracing zone c where the state where the grain culm row H is penetrated too much
It is as follows. Then, based on the outputs of the potentiometers R and R of the copying sensors S ₁ and S ₂ , that is, the detected deviation amount r, the pair of left and right The vehicle is configured to control the opening and closing of a pair of clutches 9 that individually disconnect and disconnect the drive of the crawler traveling device 4, thereby steering the vehicle. In addition, the left and right scanning sensors S ₁ and S ₂
As described above, shallow scanning zone a, dead zone b, and deep scanning zone c can be determined, but in this embodiment, the operation is performed by determining whether or not deep scanning zone c exists. It is configured to face the That is, when the left side scanning sensor _S1 detects the deep scanning zone c, the clutch (hereinafter referred to as the left side clutch) 9 for the left side crawler traveling device 4 is disconnected to perform leftward steering. When the right side scanning sensor _S2 detects the deep scanning zone c, the clutch (hereinafter referred to as the right side clutch) 9 for the right side crawler traveling device 4 is disengaged to perform rightward steering. There is.

Each of the pair of clutches 9, 9 is biased back to the entry side, and each clutch 9 is configured to be disengaged by pulling and operating an operating lever 10 provided corresponding to each clutch 9. ing. That is, a hydraulic cylinder 11 for pulling and operating the operating lever 10 and an electromagnetic valve 12 for controlling its operation are provided. By selectively turning on the left and right solenoids 12a and 12b of the electromagnetic valve 12, the pair of clutches 9 can be selectively disengaged.

In addition, when performing steering control based on the detected deviation amount r of the left and right scanning sensors S ₁ and S ₂ , when it is determined that steering is necessary based on the detected deviation amount r,
In order to disengage the clutch 9 of the crawler traveling device 4 on the turning direction side at the set clutch disengagement time P, the left and right solenoids 12a, 1 of the electromagnetic valve 12 are operated.
2b is turned ON for a time corresponding to clutch disengagement time P.
configured to operate. In the following description, the clutch disengagement time P may also be referred to as the ON time P of the electromagnetic valve 12.

Further, the output from the engine E is transmitted to the transmission section M via the transmission 13, and is configured to drive the pair of crawler traveling devices 4. By measuring the rotational speed of the crawler traveling device 4 with a vehicle speed sensor _S3 provided in the transmission section M, the traveling speed and traveling distance are detected. In this embodiment, a vehicle speed sensor is used to detect the frequency of steering.
The _S3 is now used to detect mileage.

As shown in FIG. 1, the stock sensor S ₀ , the left and right scanning sensors S ₁ , S ₂ , and the vehicle speed sensor
The detection information of _S3 is input to the control device G, and
Based on the input detection information, the control device G controls the left and right solenoids of the electromagnetic valve 12 in order to control the opening and closing of the pair of clutches 9 in order to cause the machine V to travel along the two grain culm rows H. 12a and 12b are selectively turned on, and in order to reduce the frequency of steering to make the aircraft V follow the grain culm row H, based on the detection result of the steering frequency, The clutch disengage time, that is, the ON time P of the electromagnetic valve 12 is automatically corrected. In other words, by using the control device G, there is a steering control means that controls on/off of the pair of clutches 9 in order to make the machine V run along the two grain culm rows, and a steering control means that controls the on/off of the pair of clutches 9 to make the machine V run along the grain culm row H. A steering control amount correction means is configured to automatically correct the ON time P of the electromagnetic valve 12 in order to reduce the frequency of steering for the purpose of reducing the steering frequency.

To explain the control operation of the control device G, when the stock sensor S ₀ is in the ON state, that is, when the reaping operation is in progress, the limited-cut grain culm row is located on the outer side of the machine body V, In addition, in order to maintain the proper state in which the uncut grain culm row is located on the front side, two grain culm rows H adjacent to the limited-cut grain culm row among the planted grain culm rows in the field are used as traveling guidelines. , and steers and controls the machine V to automatically travel along this grain culm row H. In other words, the left and right scanning sensors S ₁ and S ₂
The pair of clutches 9 are operated on and off to control the steering so that the detected deviation amount r is outside the deep scanning zone c.

During the steering control, the aircraft V moves towards the grain culm row H.
In order to reduce the frequency of steering for tracking the clutch, the clutch disengagement time, that is, the time of the electromagnetic valve 12
The ON time P will be automatically corrected.

Next, based on the flowchart shown in FIG. 2 and the explanatory diagram shown in FIG. 3, the solenoid valve 12 is turned ON.
The control operation for automatically correcting the time P will be described in detail.

This control operation basically changes the ON time P of the electromagnetic valve 12 to a standard reference time P ₀
After setting it to and starting driving, the ON time P
This is to adjust the time to the optimum time. Also,
In this embodiment, the steering frequency is detected as the distance traveled from one steering operation to the next steering operation, and the distance traveled is detected by the signal of the vehicle speed sensor _S3 . This is done by counting n.

Note that the flowchart shown in FIG.
As shown in the figure, the description is based on the assumption that the running direction is determined so that the left scanning sensor S ₁ detects the deep scanning zone c, and the running along the grain culm row H is started. .

When the control is started, an initial setting process is performed in which the ON time P is set to a standard reference time _P0 , and the number of outputs of the ON time P, that is, the number of clutch operations N is set to "0". Execute.

After that, the left scanning sensor S ₁ moves to the deep scanning zone c.
If it is determined that the deep scanning zone c is detected, the left clutch 9 is disengaged at the ON time P. After this cutting operation, it is again determined whether the left scanning sensor _S1 detects the deep scanning zone c.

When it is determined that the deep scanning zone c is detected, the clutch disengagement operation at the ON time P is repeated until the left scanning sensor _S1 no longer detects the deep scanning zone c, and then The number N of clutch operations is counted.

When it is confirmed in the above-mentioned re-judgment that the left scanning sensor S ₁ no longer detects the deep scanning zone c, a process of counting the signal of the vehicle speed sensor S ₃ and detecting the traveling distance is performed. and then the above
The ON time P is corrected based on the number of clutch operations N.

To correct this ON time P, first, multiply the predetermined value α by the number of clutch operations N and calculate the current value.
Add it to the ON time P and set it as the new ON time P. Next, when the clutch operation number N is "0", a predetermined value β smaller than the predetermined value α is subtracted from the ON time P, and the clutch operation number N is not "0". In this case, a predetermined value α/m smaller than the small predetermined value β is subtracted to prevent excessive correction.

Incidentally, the above-mentioned α is a value sufficiently smaller than the above-mentioned reference time P ₀ .

After performing the above correction, it is determined whether or not the right scanning sensor _S2 detects the deep scanning zone c. When the right side scanning sensor _S2 detects the deep scanning zone c, the count value n of the signal of the vehicle speed sensor _S3 is set as the first weight value _n1 , and the right side clutch 9 is disengaged at the ON time P. do. This cutting operation is continued until the right scanning sensor _S2 no longer detects the deep scanning zone c.

Then, the right scanning sensor S ₂ is in the deep scanning zone c.
When it is no longer detected, the process of counting the signal from the vehicle speed sensor _S3 and detecting the distance traveled is restarted.

Next, it is determined whether the left scanning sensor _S1 detects the deep scanning zone c. When it is determined that the deep scanning zone c is detected, the count value n of the signal of the vehicle speed sensor _S3 is set as the second count value _n2 , and the above-mentioned first count value _n1 is set as the second count value n2. It is determined whether or not the value _n2 is greater than or equal to the value n2, and if the value is greater than the value, the correction of the ON time P is completed, and if it is less than the value, the above-mentioned correction is repeated.

By the way, the first count value n ₁ is the second count value
The condition of n ₂ or more is satisfied when the ON time P is corrected to a time slightly shorter than the output that can remove the deep scanning zone c with one output, and then the above P=P+N・By processing α, N is reduced to 1
This is a case where the ON time P is corrected to be longer under the condition. After this process, the ON time P is slightly shortened as described above in order to prevent excessive correction, but as a whole, the ON time P is corrected to be longer.

To explain, the more the direction change angle of the aircraft V due to steering becomes excessive, the more the first count value increases.
n ₁ and the second count n ₂ become smaller. Then, the second count value _n2 becomes a value indicating the result of updating the ON time P, and the second count value n2 becomes a value indicating the result of updating the ON time P, and
n ₁ is a value indicating the result before the update. For example, if we consider the case where the field is hard and the steering performance is good, we will explain this by considering the actual operation. Immediately after starting the control, the ON time P is too long, so the first count value n ₁ becomes equivalently smaller.
As a result, the ON time P is gradually corrected to be shorter. And while repeating the correction,
This is the time that satisfies the above conditions. If this condition is satisfied, the ON time P will be output twice in conjunction with steering. Then, as the above correction is performed thereafter, the condition that the first count value n ₁ is greater than or equal to the second count value n ₂ is satisfied.

In addition, when the field is soft and steering performance is poor, the ON time P is too short immediately after starting the control, so the ON time P is output multiple times as the steering is performed. In conjunction with this, the ON time P is corrected to a sufficiently large value by the processing of P=P+N·α.

As a result of this correction, there are cases where the condition that the first count value n ₁ is equal to or greater than the second count value n ₂ is immediately satisfied, but there is also a case where the correction becomes excessive. In the case of excessive correction in this way, an appropriate ON time P is determined in the same manner as in the case where the field is hard and the steering performance is good.

[Brief explanation of drawings]

The drawings show an embodiment of the steering control device for an automatic traveling work vehicle according to the present invention, in which FIG. 1 is a block diagram of the steering control system, FIG. 2 is a flowchart of clutch disengagement time correction control, and FIG. 3 is a flowchart of clutch disengagement time correction control. FIG. 4 is an overall side view of the combine harvester, and FIG. 5 is an explanatory diagram of the scanning sensor. 4... Crawler traveling device, 9... Clutch, H
...Traveling guideline, P...clutch disengagement time, r...detection deviation amount, _S1 , _S2 ...copying sensor.

Claims (1)

[Scope of Claims] 1. Scanning sensors S ₁ and S ₂ for detecting the amount of lateral deviation with respect to the traveling guideline H of the aircraft V equipped with a pair of left and right crawler traveling devices 4, and the scanning sensors
Based on the detected deviation amount r detected by S ₁ and S ₂ , the driving of the pair of crawler traveling devices 4 is individually interrupted in order to cause the aircraft V to automatically travel along the guideline H. and steering control means for controlling the engagement and disengagement of the clutch 9 for steering, the steering control means for turning when determining that steering is necessary based on the detected deviation amount r. A steering control device for an automatic traveling work vehicle configured to disengage a clutch 9 of the crawler travel device 4 on the direction side at a set clutch disengagement time P, the vehicle The automatic driving operation is equipped with a steering control amount correction means that automatically corrects the clutch disengagement time P based on the detection result of the operation frequency in order to reduce the frequency of steering to follow the operation frequency. Car steering control device.