JPS6233606B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for installing a light receiving device on a vehicle body in which a plurality of light receiving elements are arranged on a light receiving surface for receiving beam light emitted from a light projecting device placed at a predetermined position. The present invention relates to a working vehicle configured to automatically control the traveling direction based on the detection result of the light receiving position on the light receiving surface of the light receiving device.

Conventionally, in order to automatically drive a work vehicle such as a lawnmowing vehicle straight in a predetermined direction, a light projector that emits a beam of light such as a laser in a predetermined direction is placed at a predetermined position, and a projector that emits this beam light is placed at a predetermined position. A means for automatically controlling the running direction of the work vehicle by providing a light receiving device on the vehicle body to receive the light beam and guiding it by the beam light has been adopted.

However, since laser light in particular has the property of traveling in a straight line as a small beam, if the vehicle body swings up and down due to the condition of the ground on which the work vehicle is traveling, the light receiving device will not be able to stably receive the light. The drawback was that accurate automatic control of the running direction was no longer possible.

The present invention aims to eliminate such conventional drawbacks, and the light receiving elements are arranged in a matrix on the light receiving surface, and the light receiving elements other than the light receiving elements in the reference row at the center in the vertical direction The light receiving device is configured to be automatically controlled to move up and down with respect to the vehicle body separately from the working device so that when the beam light is received by the light receiving element of the reference row, the light receiving device is received by the light receiving element of the reference row. It is characterized by

According to the above characteristic structure, even if the work vehicle is traveling on an uneven ground and the vehicle body swings up and down, or the traveling body moves up and down with respect to the height of the beam from the light projector due to the height of the ground, The light receiving device installed on the vehicle body is automatically raised and lowered to counteract the vertical movement of the vehicle body, and stable light reception is possible at all times, making it possible to accurately control the traveling direction of the work vehicle. In particular, since the light is always controlled to be received by the light-receiving element located in the reference row in the vertical center of the light-receiving surface, even if the vehicle body swings up and down a little or moves on a slope, the beam light will remain unchanged. This has the effect of allowing work to be continued while minimizing the inconvenience of the light coming off the light-receiving surface.

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

FIG. 1 is a schematic side view showing the relationship between a light projecting device 1 and a light receiving device 4 in controlling the running direction of a lawn mowing vehicle 3 using laser light.

A beam-shaped laser beam 2 is projected in a fixed direction from a projection device 1 placed at a predetermined position on the ground. This laser beam 2 is received by a light receiving device 4 provided at the front of a lawn mowing vehicle 3 which is equipped with a lawn mowing device A as a working device in the center of the body. A large number of light receiving elements S... are arranged in a matrix on the light receiving surface of the light receiving device 4, and as described later, based on the detection result of which light receiving element S has received the beam light 2, the lawn mower The work vehicle 3 is guided along the light beam 2 and automatically controlled to travel in a predetermined direction while mowing the lawn.

2 and 3 are a front view and a side view schematically showing the structure of the light receiving device 4. FIG.

A light receiving device 4 supported by a support frame 6 is provided in the front frame 5 of the lawn mowing vehicle 3, and as described above, this light receiving device 4 has a light receiving surface in the row direction _A1 to _A5 column direction. It is composed of a plurality of light-receiving elements S arranged in a matrix in _B1 to _B5 , respectively, and the light-receiving elements S disposed in the central portions _A3 and _B3 are used as reference light-receiving positions.

Furthermore, the light receiving device 4 has its support frame 6
is driven by a motor 7 via a gear box 8 and supported so as to be able to move up and down.

The moving distance of the light receiving position as the light receiving device 4 moves up and down by one rotation of the gearbox 8 corresponds to one row of the light receiving elements S arranged in the matrix (for example, the distance between _B1 and _B2 ). It is structured as follows.

Further, the gear box 8 is provided with a position detection sensor 9 that detects the number of rotations for each rotation and detects the amount of movement of the light receiving device 4.

The operations of the light receiving position control mechanism of the light receiving device 4 and the traveling direction control mechanism of the vehicle body constructed as described above will be explained below with reference to the block diagram shown in FIG.

For detecting the light receiving position in the vertical direction (column direction),
The photodetector outputs of A ₁ to _{A 5} on the same column are converted to each column B ₁ to _{B 5.}
Performs logical OR processing and sends I/O to the arithmetic unit 10.
Input via port 11.

On the other hand, similarly, in order to detect the light receiving position in the left and right direction (row direction), the light receiving element outputs of B ₁ to _{B 5} on the same row are logically summed and ORed for each row A ₁ to A ₅ , and the arithmetic unit 10 is input through the I/0 port 11.

Further, the output of the position detection sensor 9 provided in the gear box 8 is input to the arithmetic unit 10 via the I/0 port 11.

The arithmetic device 10 includes the I/0 port 11,
The light receiving device 4 is composed of a CPU 12 and a memory 13, and receives input via the I/0 port 11 according to a program stored in the memory 13.
Based on the position of the light receiving element where the light is received, I/0
A signal for controlling the motor 7 and a steering solenoid valve 14 for controlling the running direction (described later) is outputted through the port 11.

First, a light receiving position control mechanism by automatically raising and lowering the light receiving device 4 will be described in detail below.

As the lawn mowing vehicle 3 moves, the laser beam 2 from the light projecting device 1 reaches the reference light receiving element array of the light receiving device 4.
When light is received by a light-receiving element S other than _B3 , for example, on the _B2 column, the CPU 12 of the arithmetic unit 10 senses that the light-receiving position has changed one position upward in the column direction.

Then, a signal for forward rotation of the motor 7 is outputted from the I/0 port 11, and the light receiving device 4 is raised until the position detection sensor 9 detects the amount of movement for one column.

Similarly, when light is received by the light receiving element S on the _B1 row, the motor 7 is rotated in the forward direction until the position detection sensor 9 detects the amount of movement for two rows.

Furthermore, B ₄ or B ₅ below the reference row B ₃
When light is received on a row, the motor 7 is reversely rotated to lower the light receiving device 4 by a predetermined row.

In this way, even if the lawn mowing vehicle 3 swings up and down due to its running condition, the light receiving device 4 is automatically raised and lowered so that it is always aligned with the reference line.
The light receiving element S on B ₃ can receive the laser beam 2 from the light projecting device 1.

Next, when the light receiving element position is shifted in the left-right direction, that is, in the row direction A ₁ to _{A 5} of the light receiving device 4, a traveling direction control mechanism by steering control of the steering wheels 15, 15 of the lawn mowing vehicle 3 will be described in detail below. do.

As the lawn mowing vehicle 3 moves, the light projecting device 1
When the laser beam 2 from 2 is received by a light receiving element S other than the reference light receiving element row _A3 of the light receiving device 4, for example, on the _A2 row, the CPU 12 of the arithmetic unit 10 receives the light one position to the right in the row direction. Senses when the device changes.

Then, from I/0 port 11, buffer 16,
16', the steering solenoid valve 14 is pulse-driven to steer the aircraft to the left by a predetermined amount, thereby controlling the aircraft to the left.

Similarly, when light reception is detected on the _A1 row, the solenoid valve 14 is driven to steer the vehicle to the left by a predetermined amount corresponding to the 2nd position.

Further, when the light receiving device deviates to the left from the reference row A ₃ (row A ₄ , row A ₅ ), the solenoid valve 14 is driven to steer it to the right by a corresponding predetermined amount, contrary to the above.

In this way, even if the running direction of the lawn mowing vehicle 3 deviates to the left or right due to its running condition, the vehicle body can be automatically steered in the opposite direction in accordance with the amount of deviation, thereby mowing the lawn. The work vehicle 3 is guided by the laser beam 2 and travels straight ahead.

In the drawing, 17 is a hydraulic pump, and 18 is a hydraulic cylinder.

FIG. 5 is a flowchart showing the operation of the light receiving position control and traveling direction control of the arithmetic unit 10.

FIG. 6 is a side sectional view showing the structure of the light receiving element S.
The light focused by a lens 20 provided inside the front of the cylindrical body 19 is received by a photodiode S' disposed at the bottom of the cylindrical body 19, and the output of this diode S' is detected by a detector 21. The configuration is such that a laser light detection signal is output to the arithmetic unit 10.

FIG. 7 is a plan sectional view showing another embodiment of the light receiving element S, in which the bottom of the cylindrical body 19 is curved and a plurality of photodiodes S' are arranged on this curved surface. ing.

In this way, when a plurality of photodiodes S' are provided, even finer vehicle body rocking can be detected, and more accurate straight-line running control of the vehicle body can be performed.

[Brief explanation of the drawing]

The drawings show an embodiment of a working vehicle with a running direction control sensor according to the present invention, and FIG. 1 is a schematic side view showing the relationship between a light projecting device and a light receiving device, and FIG. 2 is a schematic front view of the structure of the light receiving device. , Fig. 3 is a schematic side view of the structure of the light receiving device, Fig. 4 is a block diagram of the control mechanism, Fig. 5 is a flowchart thereof, Fig. 6 is a side sectional view showing the structure of the light receiving element, and Fig. 7. FIG. 3 is a plan cross-sectional view showing another embodiment of the light receiving element. 1...Light projector, 2...Beam light, 3...Working vehicle, 4...Light receiving device, A...Working device, S...Light receiving element, _B3 ...Reference row.

Claims (1)

[Claims] 1. The traveling vehicle body is equipped with the working device A, and a plurality of light receiving elements S... are provided on the light receiving surface for receiving the beam light 2 emitted from the light projecting device 1 placed at a predetermined position on the ground. A work vehicle is provided with a light receiving device 4 arranged therein, and is configured to automatically control the traveling direction based on the detection result of the light receiving position on the light receiving surface of the light receiving device 4, and the light receiving device S... Arranged in a matrix on the surface,
In addition, when the light receiving element S... other than the light receiving element S in the reference row B ₃ in the center in the vertical direction receives the beam light 2, the light receiving element S in the reference row B ₃ receives the beam light 2. A work vehicle equipped with a running direction control sensor, characterized in that the light receiving device 4 is configured to be automatically controlled to raise and lower with respect to the vehicle body separately from the work device A.