JPH045205B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an automatic working vehicle such as an automatic lawn mowing working vehicle, and more particularly, to an automatic working vehicle such as an automatic lawn mowing working vehicle, and more particularly, to This invention relates to an automatic driving work vehicle equipped with tracing sensors on each side of the front left and right sides of the vehicle body.

[Conventional technology]

Conventionally, this type of autonomous work vehicle has been equipped with sensors on the left and right sides of the vehicle body to detect the boundaries of the driving area in order to automatically travel on a predetermined travel course. So-called tracing control, in which steering control is performed based on the detection results, has been performed.

Then, a configuration is adopted in which it is determined whether to perform steering control in response to only the boundary detection result of either of the two sensors, depending on the traveling direction, that is, on which side the boundary is adjacent to the left or right with respect to the vehicle body. was.

[Problem to be solved by the invention]

However, in the conventional structure described above, only one of the pair of left and right scanning sensors was used to perform steering control, so it is particularly difficult to use automatic driving vehicles, lawn mowing vehicles, and ground-based vehicles such as lawn mowing vehicles. When configured as follows, there were inconveniences as shown below.

That is, for example, the left and right scanning sensors of a lawn mower are each composed of a pair of optical sensors,
Based on the combination of the grass detection results of the pair of optical sensors, the boundary between the treated work area newly created by ground work and the untreated work area is configured to be detected as the boundary of the driving area. , the condition of the above-mentioned lawn is not always good, and the pair of sensors that make up one of the contouring sensors that follow the boundary detects a condition of tracing to the boundary that is theoretically impossible (for example, if the condition of the lawn is not always good). There is a combination in which the sensor on the mowed field detects the presence of grass and the sensor on the unmowed field detects no grass.In that case, the vehicle should be controlled to move toward the mowed field, but In the past, it was necessary to perform simple control such as simply making the vehicle go straight, so if the actual driving ground was in poor condition (for example, the grass was sparse),
There were disadvantages in that the tracking ability to follow the boundaries deteriorated and the work traces became undulating, resulting in poor aesthetic appearance.

The present invention has been made in view of the above-mentioned circumstances, and its object is to provide an automatic vehicle equipped with a steering control means that can always accurately follow the boundaries of the driving area (work area) even when the conditions of the driving area (work area) are poor. The objective is to provide a traveling work vehicle.

[Means to solve the problem]

In order to achieve the above object, an automatic driving work vehicle according to the present invention is provided with profiling sensors on the front left and right sides of the vehicle body for detecting the boundary between the treated work area and the untreated work area in the traveling area, and A control means is provided for controlling the steering wheel based on the boundary detection result, and the left and right scanning sensors individually identify whether the ground to be detected is a treated work area or an untreated work area. The configuration is characterized in that a pair of sensor units are arranged side by side on the left and right, respectively, and the control means is set with the control procedures described in [A] to [C] below. .

[B] When both sensor sections of one of the two scanning sensors that scan the boundary are detecting the processed work area, steering control is performed toward the other scanning sensor.

[B] When the outer sensor part of said one copying sensor that copies the boundary detects a treated work area and the inner sensor part detects an untreated work area, or When the outer sensor unit detects an untreated work area, the inner sensor unit detects a treated work area, and both sensor units of the other copying sensor are detecting an untreated work area, Steering is controlled to keep the vehicle moving straight.

[C] When the detection result of the copying sensor is other than the above, steering control is performed toward one copying sensor that copies the boundary.

The above configuration of the present invention will be explained with reference to FIG. 1. The boundary arrangement position setting means 1 sets in advance which side of the left and right scanning sensors A and A' the boundary of the running area is located. At the same time, based on this setting, the table to be used in the combination discrimination table 2 of the boundary detection results of the sensor portions of the scanning sensors A and A', which are set in advance in a symmetrical relationship, is determined. Then, according to which side of the scanning sensors A and A' the boundary is located, and based on the combination of the boundary detection results of the sensor sections of both scanning sensors A and A', the table 2 is Determine a flag F for controlling whether to steer left or right or to drive straight ahead, and set this flag F.
The driving wheel 4 is thus configured to be steered by a predetermined amount via the actuator drive means 3.

Due to the above characteristic structure, the following actions and effects have been achieved.

[Effect]

In other words, when both sensor sections of the one of the two scanning sensors that scans the boundary detect the treated work area, it is clearly seen that the vehicle body is displaced from the boundary to the treated work area. Therefore, regardless of the detection result of the other copying sensor, the outer sensor part of one copying sensor that tracks the boundary by steering the vehicle toward the untreated work area detects the treated work area, and When the sensor on the edge detects an untreated work area, it has detected that the boundary is being traced correctly, so it will move straight regardless of the detection result of the other tracing sensor, and the untreated work area will be crossed. Both sensor parts of the other copying sensor located at When a processed work area is being detected, the work area near the boundary is simply locally abnormal, and the system moves straight ahead, avoids the abnormal detection state without deviating significantly from the boundary, and changes the detection result to other detection results. In this case, when both sensor parts of one copying sensor that traces the boundary detect an untreated work area, the vehicle body is steered to the treated work area regardless of the detection result of the other copying sensor, and the other one Even though the scanning sensor is located beside the untreated work area, both sensor parts are not in a state to detect the untreated work area, that is, the working area is bad and one of the scanning sensors is located beside the untreated work area. If there is an abnormality in boundary detection, the vehicle is steered toward the untreated work area to prevent the vehicle from unduly entering the untreated area.

〔Effect of the invention〕

Therefore, one of the tracing sensors installed on the left and right sides of the vehicle body performs detection for tracing the boundary, and the other detects the state of the untreated work area, and steering control is performed based on these detection results, so the driving area Fine-grained tracing control is performed that takes into account not only the boundaries but also the running ground conditions, which improves the ability to follow boundaries and prevents untreated work areas or undulating work tracks. The inconvenience has been resolved.

〔Example〕

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

As shown in FIG. 2, a lawn mowing device 8 is suspended between the front and rear wheels 6, 7 of the vehicle body 5 so as to be movable up and down, and the lawn mowing device 8 is vertically movably suspended in front of the vehicle body 5. Copying sensors A and A' having the configuration described later for determining the boundary are provided on the front left and right sides of the vehicle body 5, respectively.
The lawn mowing work vehicle is configured as an automatic traveling work vehicle that can automatically travel along a predetermined travel course by controlling the steering based on the combination of the boundary detection results of the scanning sensors A and A'.

The scanning sensors A and A' are a pair of optical sensors S1, S2, S3, and S4 having the same configuration, respectively.
It is composed of.

That is, the optical sensors S1, S2, S3, S4
As shown in FIG. 3, U-shaped sensor frames 9, 9 each disposed adjacent to the vehicle body 5 in the left and right direction are fixed to a sensor mounting frame 10 provided on the lawn mower 8. A light emitting element P1 and a light receiving element P2 are provided as a pair on the inner facing surface of the sensor frame 9, and the vehicle body 5 is provided between the light emitting element P1 and the light receiving element P2.
The structure is configured to determine the boundary between unmowed land and mowed land by sensing the presence or absence of grass introduced as the machine travels. Note that the sensor A is not limited to one using the optical sensors S1, S2, S3, and S4, and may be constructed from any type of sensor, whether contact type or non-contact type.

The front wheels 6, 6 serve as steering wheels 4,
Normally, it is configured to be steered by a predetermined amount in the left-right direction by a hydraulic cylinder 11 as the drive means 3 based on the boundary detection results of the copying sensors A and A'.

A control system configured as described above that performs steering control based on the boundary detection results of the scanning sensors A and A' will be described below.

As shown in FIG. 4, the control system connects the four optical sensors constituting the scanning sensors A and A' via an input interface 13 to an arithmetic unit 12, the main part of which is composed of a microcomputer. Grass detection signals from S1, S2, S3, and S4 are input, as well as a signal from a switch SW serving as a boundary placement position setting means 1, and the signals from each of these sensors A, A' and switch SW are input. Based on this, the control flag F corresponding to the table 2 shown in FIG. It is configured so that it can be output.

That is, whether the vehicle body 5 of the traveling work vehicle is located on the left side of the boundary and performs work while turning around the work area to the left, or is it located on the right side of the boundary and performs work while turning around the work area to the right. According to the following, the processing unit 12 is provided to determine which of the left and right copying sensors A and A' of the vehicle body 5 is to be recognized by the arithmetic unit 12 as the sensor that copies the boundary.
A switch as the boundary arrangement position setting means 1
Operate SW to set the conditions of Table 2. In other words, the switch SW is closed and turned ON.
When the signal is input to the arithmetic unit 12, the table 2 is set as shown in FIG.
The control flag F is selected from the combination of the output signals of 3 and S4. Further, when the switch SW is opened and an OFF signal is input to the arithmetic unit 12, the table 2 is set to
3. Control flag F is determined from the combination of output signals of S4.
The usage conditions of Table 2 are set so that .

In Table 2, each optical sensor S
1, S2, S3, and S4, as shown in FIG. The control flag F is determined as follows. In FIG. 5, X indicates that the output signals of the optical sensors S1 to S4 are unstable, that is,
This indicates that the level may be either high level H or low level L. In this example,
The table set at 1 is for working with the vehicle body 5 turning counterclockwise, and the table set at 2 is for working with the car body 5 turning clockwise.

In this way, based on the combination of the output signal of the switch SW and the output signals of all four optical sensors S1, S2, S3, and S4 constituting the both scanning sensors A and A', In each working state, the table 2 determines whether the steering operation is to be performed in the left or right direction, or whether the vehicle should simply be driven straight ahead.

Further, FIG. 6 is a flowchart showing the operation of the arithmetic unit 12, and shows the operation of the switch SW ON/OFF.
After the OFF judgment, if the flag F determined by the table shown in FIG. 5 is 1, the front wheels 6, 6
This shows a procedure in which the steering wheel is operated by a predetermined amount to the left, when the value is -1, the steering operation is performed by a predetermined amount to the right, and when the value is 0, the vehicle body 5 is driven so as to move straight.

[Brief explanation of drawings]

FIG. 1 is a drawing for explaining the configuration of the present invention,
Figure 2 and subsequent figures show an embodiment of the automatic steering vehicle according to the present invention, in which Figure 2 is an overall plan view of the lawn mowing vehicle, Figure 3 is a front view of main parts showing the structure of the scanning sensor, and Figure 4. 5 is a block diagram of the control system, FIG. 5 is a discrimination table, and FIG. 6 is a flowchart showing the operation of the arithmetic unit. 4, 6...Steering wheel, 5...Vehicle body, A, A'...
...Copying sensor, S1, S2, S3, S4...Sensor section.

Claims (1)

[Scope of Claims] 1. Contouring sensors A, A' are provided on the front left and right sides of the vehicle body 5, respectively, to detect the boundary between the treated working area and the untreated working area in the traveling area, and both of the scanning sensors A, A' A control means is provided for controlling the steering wheel 4 based on the boundary detection result, and the left and right scanning sensors A, A' are controlled to determine whether the ground to be detected is a treated work area or an untreated work area. A pair of sensor sections S that individually identify the
1, S2, S3, and S4 are arranged side by side on the left and right, and the control means is further set with the control procedures described in [A] to [C] below. A self-driving work vehicle. [B] When both sensor sections S1, S2 or S3, S4 of one of the two scanning sensors A and A' that scans the boundary are detecting the processed work area, the other one is detecting the processed work area. Steering control is performed toward scanning sensor A' or A side. [B] The outer sensor part S1 or S of the one copying sensor A or A' that copies the boundary
4 detects a treated work area and the inner sensor part S2 or S3 detects an untreated work place, or when the outer sensor part S1 or S4 of one of the copying sensors A or A' The untreated work area is detected, the inner sensor section S2 or S3 detects the treated work area, and both sensor sections S3, S4 or S1, S of the other copying sensor A' or A are detected.
2 detects an untreated work area, the steering is controlled to go straight. [C] When the detection results of both the scanning sensors A and A' are other than the above, steering control is performed toward one of the scanning sensors A and A' that traces the boundary.