JPS61166302A - Boundary detector of working vehicle - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention mainly relates to border control of work vehicles used to automatically move work equipment along the border between untreated work areas and treated work areas. Regarding the detection device, in detail, there is an untreated work area detection means that detects that the height of the work target is higher than the discrimination reference height, and a treated work area detection means that detects that the height of the work target is lower than the discrimination reference height. means are provided to detect different locations in the width direction of the working device, and based on the detection information of both the detection means, the working device detects the boundary between the untreated work area and the treated work area. The present invention relates to a boundary detection device for a work vehicle configured to determine the position of a work vehicle.

[Conventional technology]

Conventionally, in such boundary detection devices for work vehicles, the discrimination reference height has been set so that the discrimination reference height of the untreated work area detection means and the discrimination reference height of the treated work area detection means are equal. .

[Problem that the invention seeks to solve]

However, if the discrimination reference height is set as in the past, there is a risk that the rain detection means will cause false detection and will not be able to accurately detect the position of the working equipment with respect to the boundary. This may cause problems such as unprocessed areas.

The above erroneous detection will be explained in detail by taking as an example a detection device attached to a lawn mowing vehicle equipped with a mower as a working device.

In other words, for lawn mowing vehicles,
As shown in (+1), for example, two first and second sensors (St), (S) of the photo ink club type in which a light emitting element (P, ) and a light receiving element (P2) are arranged facing each other, Each sensor (s+), (s
z) is a treated work area (C) or an untreated work area (B
). In other words, Figure 4 (
In (a) and (b), the first sensor (St) acts as a treated work area detection means that detects that the height of the grass is lower than the discrimination reference height in an unshielded state; The second sensor (St) acts as an untreated work area detection means that detects that the height of the grass is higher than the discrimination reference height in a light-shielded state, and
The discrimination reference height of these sensors (St) and (SZ) is set as the ground height of each sensor (St) and (SZ).

When setting the discrimination reference height of each sensor (Sυ, (S)) to the same height, for example, as shown in Fig. If the determination reference height is set low to enable the processing to be carried out, there is a risk that the first sensor (St) may cause false detection if there is long grass due to uncut work, etc. in the treated work area (C). Figure 4 (
As shown in rj), if the discrimination reference height is set high in order to accurately detect the treated work area (C),
If there is short grass in the untreated work area (B) due to growth retardation, etc., there is a risk that the second sensor (S2) will cause false detection.

In other words, in both work areas (B) and (C), there are places where the height of the work object changes unexpectedly, so setting the discrimination reference height to the same height may result in an error. Detection was unavoidable.

[Means for solving problems]

The characteristic configuration of the present invention is that the discrimination reference height of the untreated work area detection means is set lower than the discrimination reference height of the treated work area detection means, and its functions and effects are as follows. .

[For production]

In other words, the discrimination reference height of the untreated work area detection means can be made sufficiently lower than the height of the work object on the untreated side, so that even if there is a short work object in the untreated work area, , the work target can be reliably detected, and
The discrimination reference height of the treated work area detection means can be made sufficiently higher than the height of the work object on the treated side, so that even if there is a long work object on the treated work area, the work can be done easily. Unnecessary detection of a target can be suppressed.

〔Effect of the invention〕

Therefore, even if the height of the work object is uneven, the rain detection means can accurately detect both the untreated work area and the treated work area, and accurately detect the position of the work equipment with respect to the boundary. Therefore, when automatically moving the work equipment along the boundary,
A boundary detection device for a working vehicle that can be used more conveniently has been obtained, which can move the working device accurately along the boundary and suppress troubles such as the generation of unprocessed parts.

〔Example〕

As shown in Figure 3, a vehicle body (1) configured to allow steering operation of both the front and rear wheels (2) and (3).
A mower (4) as a working device equipped with a disc-shaped cutting blade is suspended vertically in the middle of the area, and the boundary (L) between the untreated work area (B) and the treated work area (C) is suspended. A copying sensor (5) for detecting is provided at the tip of the frame (6) fixed to the mower (4), and based on detection information of the copying sensor (5) 4) is configured to perform steering control so as to move the mower along the boundary (L) between the untreated work area (B) and the treated work area (C).

In addition, the front wheels (2), (2) and the rear wheels (3),
Since both (3) are configured to be able to be steered, by steering the front and rear wheels (2) and (3) in the same direction, the vehicle body (1) can be translated in parallel without changing its direction. The steering system is configured so that the vehicle can be selected between a steering system that causes the vehicle to turn, and a steering system that allows the vehicle to turn with a very small turning radius by steering the front and rear wheels (2) and (3) in relatively opposite directions. Further, the copying sensor (5) is provided on each side of the vehicle body, and these sensors (5) are connected to the boundary (I4).
It is configured so that it can be selectively used depending on the position of the vehicle body (1) relative to the vehicle body (1).

Further, a driven wheel (7A) that rotates as the vehicle body (1) runs is provided at the rear of the vehicle body (1), and a driven wheel (7A) is provided at the rear of the vehicle body (1).
A distance sensor (7) that generates a pulse signal every time the vehicle (7A) rotates by a predetermined angle is provided, and the distance traveled can be detected based on the pulse signal. In addition, the upper part of the car body (1
) is provided with a geomagnetic sensing type orientation sensor (8) that detects the traveling direction (azimuth) of the vehicle.

Next, the scanning sensor (5) will be described in detail.

Note that since the two copying sensors (5) and (5) have the same configuration, one copying sensor (5) will be described below.

As shown in Figure 1, a light emitting element (P1) and a light receiving element (P
2) on the support frame (9) with the pixel elements (Pυ, (pg) facing each other, and check that the height of the grass to be worked on is lower than the discrimination reference height (H1). Photointerplater type 1 as means for detecting treated work area
The sensor (S1) and the height of the grass are the determination reference height (H2
) is configured as a photo-interrupter type second sensor (S2) as an untreated work area detecting means.

That is, each sensor (S1), (St) detects the presence or absence of grass passing between the light emitting element (P1) and the light receiving element (P2), thereby separating the untreated work area (B) and the treated work area. The first sensor (S,) detects the treated work area (C), and the second sensor (S8) detects which of the work areas (C) it is located on.
Boundary (L) indicates the state in which untreated work area (B) is detected.
The configuration is such that the positional relationship between the boundary (L) and the vehicle body (1), that is, the mower (4) is determined as the appropriate state for the vehicle.

Then, the ground height of the two sensors (S1) and (St) is set so that the second sensor (S) is located lower than the first sensor (S1), and the untreated work area (B) is The discrimination reference height (H2) of the second sensor (S2) that detects the treated work area (C) is set lower than the discrimination reference height (Hυ) of the sensor (S,) that detects the treated work area (C). If there is short grass in the treated work area (CB), and if the treated work area (CB) has short grass,
), each sensor (S1)
, (St) is suppressed from erroneous detection.

The support frame (9) is bolted to a plate-shaped body (10) attached to the frame (6).

By the way, the discrimination signals of the untreated working area (B) and the treated working area (C) obtained from each sensor (Sυ, Therefore, it is configured to be input to the control device (1) described later after performing integral processing so as to become a continuous discrimination signal.

To integrate the signals from the optical sensors (S1) and (Ss), as shown in FIG. 2, the number of output pulses from the distance sensor (7) is counted and carried every preset count value. A programmable counter (11) that outputs a signal (P4) and a flip-flop (11) that is reset by the carry signal (P4) of this counter (11).
12) is provided, and the output signal (P,
) is configured to reset the counter (11) and set the flip-flop (12), so that the counter (11) and the flip-flop (12) constitute a digital filter (13). Continuous discrimination signals (Po) corresponding to the respective states of the untreated work area (B) and the treated work area (C) are obtained.

Next, the operation of this digital filter (13) will be briefly explained.

The counter (11) is repeatedly reset by the output pulse signal (P,) of the light receiving element (R2) regardless of its count value, and the flip-flop (11)
2) is set. Then, when the grass disappears, this pulse signal (P,) goes to "L" level, and the distance sensor (11) reaches the count value corresponding to the unit distance traveled by the distance sensor (11). 7), the counter (11) outputs a carry signal (R4) to reset the flip-flop (12).

Therefore, the discrimination signal (Po) output from this flip-flop (12) continuously repeats the "H" level corresponding to the grass sensing state or the "L" level corresponding to the no grass state.

Hereinafter, the copying sensor (5), (5), distance sensor (
7) and each detected parameter by the orientation sensor (8), a control configuration for automatically driving the lawn mowing vehicle will be described.

As shown in FIG. 2, each sensor (5
), (7), and (8) are input, and the signals are output from the control device (I) by processing the detected parameters by each of these sensors (5), (7), and (8). In order to automatically control the running direction and speed of the vehicle body (1) using control signals, the front and rear wheels (2
), (3) a pair of hydraulic cylinders (14), (15) each of which is operated separately, and an electromagnetic valve (1) for each.
6), (17) and hydraulic continuously variable transmission (18)
It is configured to drive a motor (19) that changes speed.

In Fig. 2, (R1) and (R,) are the front and rear wheels (2).
, (3) is a potentiometer for detecting the actual steering amount and feeding it to the control device (I), and (R3) is a potentiometer for similarly detecting the shift position of the transmission (18) and feeding it to the control device (I). This is a potentiometer for feeding back to (I).

To explain the travel control operation specifically, the size and length of the four sides are measured by outer circumference teaching, etc., and a work area is formed in advance with the outside of the outer circumference as a treated work area (C). (In addition, by the above-mentioned outer circumference teaching etc., the directions of the four sides will also be measured as the reference direction. After that, the stored information for automatically moving to the next stroke after the completion of the -stroke, The copying sensor (5
), the boundary (
L), and each time the -stroke is completed, the lawn mowing work for the work area is automatically performed while automatically traveling to the next stroke.

Incidentally, the reference orientation is used as information for automatically correcting the orientation of the vehicle body so that the straight running direction becomes the direction of each stroke (any one of the four sides). In addition, as for the running mode, so-called circular mowing, in which the direction is turned 180 degrees after completing one stroke and moving to the next stroke, and so-called circular mowing, in which the direction is changed 90 degrees after completing one stroke and moving to the next stroke, can be applied. .

[Another example]

In the embodiment described above, steering control was applied as a means for automatically changing the position of the working device (4) so as to move the working device (4) along the boundary (L). The working device (4) itself may be movable back and forth and left and right with respect to (1), so that the working device (4) can be moved along the boundary (L).

Further, in the above embodiment, a photo-interrupter type sensor (
S+) and (Sz) are used, but a detection piece that can freely touch the workpiece is provided above the workpiece so that it can move up and down and is biased downward, and the height of the workpiece is detected based on the vertical position of the detection piece. Contact type sensors, ultrasonic sensors, etc. that detect the height of the work target based on the time it takes for ultrasonic waves emitted from above the work target to be reflected at the top of the work target and returned to the work target. It may also be configured using In the case of the contact sensor, the discrimination reference height is set as the upper and lower linked positions of the detection piece, and in the case of an ultrasonic sensor, the discrimination reference height is set as the height at which the ultrasonic wave returns. The appropriate time will be set as the time until.

Further, in the embodiment, the case where the present invention is applied to a lawn mowing work vehicle has been exemplified, but the present invention can be applied to various work vehicles such as a harvester that works on crops.

[Brief explanation of drawings]

The drawings show an embodiment of the boundary detection device for a working vehicle according to the present invention, in which FIG. 1 is a front view of the principal parts of the scanning sensor, FIG. 2 is a block diagram of the control configuration, and FIG. 3 is an overall plan view of the lawn mowing vehicle. It is a diagram. Fig. 4 (() and (0) are front views of main parts of a copying sensor showing a conventional example. (4)...Working device, (B)...Untreated work area , (C)......treated work area, (H1)
, (H1)...Discrimination reference height, (L)...
... Boundary, (S1) ... Treated work area detection means, (S2) ... Untreated work place detection means.

Claims (1)

[Claims] An unprocessed work area detection means (S_2) detects that the height of the work target is higher than the discrimination reference height (H_2) and an already processed work area detection means (S_2) detects that the height of the work target is lower than the discrimination reference height (H_1). The processing work area detection means (S_1) is connected to the work equipment (
4), both of the detection means (S_1) and (S_2)
Based on the detection information of
A boundary detection device for a work vehicle configured to determine the position of the untreated work area detecting means (S_2), the determination reference height (H_2) of the untreated work area detecting means (S_2)
A boundary detection device for a work vehicle that is set lower than the discrimination reference height (H_1) of _1).