JPH0648924B2 - Turn control device for automated vehicle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a turn control device for an automatic work vehicle, and more specifically, to a vehicle traveling forward while turning at a predetermined angle, then moving straight forward and backward at a predetermined distance and then turning again. The present invention relates to a turn control device for an automatic traveling work vehicle that automatically turns the machine body.

[Conventional technology]

When changing the direction in the above-mentioned work vehicle, for example, in an agricultural work vehicle such as a combine, the driving force is transmitted to either the left or right crawler traveling device by disengaging the clutch or applying the brake. Turn control for turning the aircraft is performed by stopping rotation or giving a rotation difference.

In the above-mentioned turn control, when one of the left and right crawler traveling devices is caused to have a rotation difference and the other is stopped, the crawler traveling device is turned at a constant control amount such as disengaging the clutch for a preset time.

In turn control by automatic traveling, in order to simplify the control, a pre-patterned sequence is executed so that the aircraft automatically turns.

[Problems to be Solved by the Invention]

However, the work vehicle may perform work in a wetland or the like where traveling place conditions are bad, so that the slip ratio of the traveling device at the time of turn greatly varies depending on the ground condition. In particular, in a crawler traveling device, slippage during straight running is relatively small, but during turning, it is relatively easy to slip due to the shape characteristics of the ground contact surface of the crawler traveling device, and lateral slippage easily occurs. Therefore,
When turning with a constant control amount as in the past, there is a disadvantage that the slip increases and so-called lateral deviation occurs and the aircraft position after turning largely deviates from the planned position,
In the case of performing automatic turn by performing patterned turn control, the subsequent running direction may be largely deviated, and the control for the subsequent automatic run may not be normally performed.

That is, to explain with reference to a concrete example, as shown in FIG. 3 (a), when the vehicle is turned by a predetermined angle, lateral deviation occurs and the work vehicle is displaced to the position indicated by the broken line. Then, the work vehicle is positioned forward of the normal position due to the lateral shift, so even if the work vehicle is moved backward by a predetermined amount (β), the work vehicle is positioned in front of the position on the extension line of the planned approach route after turning. Stop at (in this case, the vehicle is in a straight backward state,
No slip occurs and the retract distance must be (β ')). Therefore, even if the vehicle is turned by a predetermined angle at that position, the posture due to the turning will be the posture according to the angle, but the position after the turning remains displaced.

The present invention has been made in view of the above circumstances, and an object thereof is to automatically correct an aircraft traveling route error during a turn in response to a slip ratio that changes according to a traveling ground state.

[Means for Solving the Problems]

In order to achieve the above object, a turn control device for an automated work vehicle according to the present invention is provided with a vehicle speed sensor for detecting the number of revolutions of a crawler traveling device and a direction sensor for detecting a change in the direction of the machine body. In addition to turning the aircraft by the predetermined angle based on the change in the azimuth, the vehicle is equipped with a travel route correcting means for automatically correcting the reverse distance based on the rotational speed detected by the vehicle speed sensor during the turning. Yes, its effects are as follows.

[Work]

In other words, by turning the aircraft while adjusting the turn angle based on the change in direction detected by the direction sensor, the vehicle can be turned at a constant turn angle regardless of the slip of the traveling device, and the slip ratio during that turn By detecting the number of revolutions of the traveling device detected by the sensor and correcting the retreat distance thereafter, it is possible to absorb the traveling route error of the machine body that occurs when a slip occurs. And the next turning start point is
By setting the retreat distance so as to be located on the extension line of the planned aircraft approach route after the end of the turning, the aircraft approach position for the next stroke is optimized.

〔The invention's effect〕

Due to the above characteristics, the following excellent effects have been achieved.

That is, the turn angle is controlled based on the azimuth detected by the azimuth sensor regardless of whether or not the traveling device has slipped, so that the orientation of the aircraft after the turn does not greatly deviate from the desired orientation. Then, based on the travel device drive amount during the turn, that is, the number of detection circuits by the vehicle speed sensor, the next turning point is positioned on the extension line of the planned route to enter the aircraft after turning, so that the next stroke after the turn. The body position with respect to can be set to an appropriate position regardless of the slip of the traveling device.

Therefore, it is possible to perform a stable turn regardless of the running ground condition, and it is possible to maintain a proper working state from the end of the stroke without the occurrence of meandering due to the orientation correction of the aircraft when entering the next stroke after the turn. It became so.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

As shown in Fig. 1 and Fig. 6, the mowing section (2) which causes the planted culms in the field to be mowed and which is transferred to the feed chain (1) after being transferred to the feed chain (1) while conveying the mowing culms. ), And a threshing device (3) that threshes the culms that are sandwiched and conveyed by the feed chain (1) and selectively collects the grain, and is equipped with a pair of left and right crawler traveling devices (4), (4). It is mounted on the machine body (V) and constitutes a combine as an automated guided vehicle.

Below the reaping unit (2), a stock origin sensor composed of a contact type switch that outputs an ON / OFF signal by contacting the stock of the grain stalk introduced into the reaping section (2) from the front side. (S ₀ ) is provided to detect the start / stop of the reaping work.

In addition, the attachment frame (7), (7) of the weeding tools (6a), (6b) at the left and right ends of the weeding tool (6) provided at the tip of the mowing section (2) has ) The sensor bar (8) that is biased to the front side and contacts the grain stalk introduced into the mowing section (2) and rotates the angle corresponding to the contact position to the rear side of the machine body (V) , Scanning sensors (S ₁ ) and (S ₂ ) each consisting of a potentiometer (R) for detecting the rotation angle of the sensor bar (8) are provided, respectively, and based on a change in the output signal of the potentiometer (R) The amount of lateral displacement of the vehicle (V) with respect to the row (H) is detected.

Explaining the detected deviation amounts of the left and right scanning sensors (S ₁ ) and (S ₂ ), as shown in FIG. 6, the deviation amounts are divided into three according to the change of the rotation angle of the sensor bar (8). Zones (a), (b),
It is divided into (c) and detected. That is, from the state where the sensor bar (8) is returned to the front side of the body (V) most to the state where it is rotated backward by a predetermined angle,
(H) is set as a shallow copying zone (a) that is displaced in the direction away from (H), and the grain row (H ) Is the dead zone zone (b), and the state further rotating from this dead zone zone (b) to the rear side is the grain row (H).
A deep copy zone that is too deep for
It is as (C). Then, the output of each of the potentiometers (R) and (R) of the scanning sensors (S ₁ ) and (S ₂ ), that is, the detected deviation is in any of the three zones (a), (b), and (c). The left and right crawler traveling devices (4) and (4) are operated to disengage the clutches (9) and (9) so that the detected deviation amount is within the dead zone (b). The copying control is performed in the opposite direction.

In addition, the aircraft (V) is equipped with a bearing sensor (T) that uses a geomagnetic sensor that detects the absolute bearing by sensing changes in the geomagnetism. This bearing sensor (T) detects the bearing (θ). The change in the traveling direction is detected based on the above.

The output from the engine (E) is the hydraulic continuously variable transmission (1
0) and the mission unit (M), and is configured to drive the crawler traveling devices (4), (4). The crawler traveling is performed by the vehicle speed sensor (N) provided in the mission unit (M). By measuring the number of revolutions (n) of the devices (4) and (4), the traveling speed and traveling distance are detected.

The speed change device (10) is automatically adjusted by a motor (11) to a predetermined speed change position during automatic traveling or turn control, and can be operated manually by a speed change lever (12). I am doing it. That is, the driving force transmission of the motor (11) to the operation lever (10a) of the transmission (10) is transmitted to the operation force transmission mechanism (13) of the transmission lever (12) by the friction transmission mechanism (14). It is connected through.

Then, when the stock sensor (S ₀ ) is in the ON state, alternately select each cutting mode of the line cutting mode and the horizontal cutting mode for each stroke, corresponding to each mode, the scanning sensor ( S
₁ ), (S ₂ ), and the left and right clutches (9) of the crawler traveling devices (4), (4) based on both detection information of the deviation detected by the azimuth sensor (T) and the detected azimuth (θ) By turning off one of (9) and (9), the aircraft (V) is steered so as to automatically run in the state along the grain culm row (H) and in the direction of the preset reference direction (θ ₀ ). In addition to the control, when the stock sensor (S ₀ ) turns off and the cutting work of one stroke is completed, turn control is performed to move to the next stroke, and the work area in the predetermined range is The automatic running is performed while the cutting width is gradually reduced in the inner circumferential direction.

In addition, in order to control the steering in each stroke, in the mowing mode,
In order to run along the row direction of the grain culm (H) to prevent the leftover cutting, the deviation amount detected by the scanning sensors (S ₁ ), (S ₂ ) is adjusted by the direction sensor (T). The detection direction (θ) is prioritized and used as a control parameter.
That is, when the detected deviation amount is within the dead zone (b), the detected azimuth (θ) and the reference azimuth (θ ₀ ) are compared,
(V) is controlled so that it travels in the direction of the reference direction (θ ₀ ).

On the other hand, in the horizontal cutting mode, since the direction of the grain culm row (H) to be copied becomes unclear, the direction control by the detected direction (θ) by the direction sensor (T) is performed by the copy sensor (S ₁ ). , (S ₂ )
Priority is given to the copying control by the. That is, when the detected azimuth (θ) is within the predetermined deviation provided as the azimuth dead zone with respect to the reference azimuth (θ ₀ ), based on the deviation detected by the copying sensor (S ₁ ) on the side of the cut land, The steering is controlled so that the train runs following the grain culm (H).

Hereinafter, the flowchart shown in FIG. 2 and FIG.
Turn control will be described based on the explanatory diagrams shown in (b) and (c).

That is, when the stock base sensor (S ₀ ) is turned off and the cutting work for one stroke is completed, the count value (n) by the distance sensor (N) is reset to start the turn control, and the operation shown in FIG. )
As shown in Fig. 2, the direction sensor is set so that the machine body (V) faces the next stroke direction on the cut ground outside the unprocessed work site in the next stroke direction.
While checking the change in the detected direction (θ) due to (T), the clutches (9) and (9) are turned on / off to turn by a predetermined angle (α) (provided that α <90 °). Then, the drive amount of the traveling devices (4) and (4) required for turning by the predetermined angle (α), that is, the detected rotation speed (n) of the vehicle speed sensor (N) is measured, and the rotation speed (n) is measured. Based on the table, the values (a _n ) _{n = 0,1,2 ...} of the retreat distance (β) corresponding to the slip ratios, which are tabulated in advance, are read out from the table provided in the control unit (G) to determine the vehicle speed. While checking the change in the rotational speed (n) detected by the sensor (N), the retreat distance (β) is moved straight backward. After that, by making an in-situ turn at an angle of a difference (90 ° -α) between the swung predetermined angle (α) and 90 degrees, and making a 90 degree turn as a whole, the aircraft (V ) Turns so that it points in the direction of the next stroke.

Then, by performing the turn control by the operation described above, the lateral displacement of the vehicle body (V) indicated by the broken line in FIGS. 3 (a) and 3 (b) caused by the slip caused by the difference in the field conditions (dry field, wet field, etc.) Driving route error during turn due to
Absorb (β-β ') and move it back to the position indicated by the broken line in Fig. 3 (b), and at that point, as shown in Fig. 3 (c), at a predetermined angle (90 ° -α) By turning, as shown in FIG. 4, when the work of the next stroke is started, the grass cutter (6b) on the side of the cut land is within the interval (Q) between the grass cutter (6) and the adjacent grass cutter (6). In this way, the uncut area does not occur from the start of work in the next process. The fourth
In the figure, (P) schematically shows the actual distance and the distance between the cut grass side weeding tool (6b) and the grain culm row (H).

Incidentally, the first value (a ₀ , a ₁ , a ₂ , ...) of the backward distance (β) values (a ₀ , a ₁ , a ₂ , ...) tabulated corresponding to the number of revolutions (n) detected by the vehicle speed sensor (N). a ₀ ) is the ideal distance when no slip occurs at all, and the following values (a ₁ ), (a ₂ ) ・ ・ are based on the aggregate data of the slip ratio change that occurred according to various field conditions. The address of the table can be set immediately from the detected rotation speed (n) to determine the retreat distance (β) according to the actual field conditions. The reference value is the detected rotation speed (n) when not
As (n ₀ ), the value of the retreat distance (β) may be read from the table according to the deviation of the detected rotation speed (n) from this reference value (n ₀ ), or the retreat distance (β) may be calculated. You may

BRIEF DESCRIPTION OF THE DRAWINGS The drawings show an embodiment of a turn control device for an automated guided vehicle according to the present invention, FIG. 1 is a block diagram of the control system, and FIG. 2 is a flowchart showing the operation of the control device. Figure 3
(A), (b) and (c) are explanatory diagrams of turn control, Fig. 4 is an explanatory diagram of the relationship between the machine position and the grain row at the beginning of cutting, and Fig. 5 is an overall side view of the combine, FIG. 6 is an explanatory diagram of the scanning sensor. (V) …… Airframe, (N) …… Vehicle speed sensor, (T) …… Direction sensor, (4) …… Crawler traveling device, (n) …… Rotation speed, (θ)…
… Detection direction, (β) …… Retreat distance.

Claims (1)

[Claims] Claims: 1. After moving forward while turning a predetermined angle (α), go straight forward and backward for a predetermined distance (β) and turn again,
A turn control device for an automatic traveling work vehicle that automatically turns the vehicle body (v), including a vehicle speed sensor (N) that detects the rotation speed (n) of the crawler type traveling device (4), and the vehicle body (V). A direction sensor (T) that detects a change in the direction of the vehicle is provided, and the aircraft (V) is turned based on the change in the direction of detection (θ) by the direction sensor (T) while turning the specified angle (α). A turn control device for an automatic traveling work vehicle, comprising: travel route correction means for automatically correcting the reverse distance (β) based on the rotational speed (n) detected by the vehicle speed sensor (N).