JPH06168024A - Work vehicle guide device using beam light - Google Patents

Abstract

(57) [Summary] [Construction] In each of a plurality of work steps parallel to each other, a beam light projection means 5 is provided for projecting a beam light for guiding from one end side to the other end side of the work steps. The vehicle 1 is provided with a light receiving means 8 for receiving a light beam and a control means for controlling the work vehicle 1 to automatically travel along a work stroke based on the light receiving information of the light receiving means 8. In the light-guided work guiding apparatus, the beam light projection means 5 is configured to project the light beam by superposing different identification information in each of the plurality of work steps, and the control means. It is configured to determine the work process based on the information. [Effect] It is possible to accurately perform the operation of the work vehicle turning at the terminal end of the work stroke and transferring to the next adjacent stroke based on the identification information.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is provided with beam light projection means for projecting a beam light for guiding from one end side to the other end side of a work stroke in each of a plurality of parallel work strokes. The work vehicle is provided with light receiving means for receiving the light beam, and control means for controlling the work vehicle to automatically travel along a work stroke based on light receiving information of the light receiving means. The present invention relates to a work vehicle guidance device.

[0002]

2. Description of the Related Art A work guidance system utilizing such beam light is
It is for guiding an unmanned work vehicle such as a mowing robot along a predetermined work process. Within the rectangular work area, a plurality of linear work steps are set at predetermined intervals, and each work step is formed by the beam light projected by the beam light projection means. The work vehicle turns at the end of the work stroke and transfers to the next adjacent stroke, and sequentially moves from the work stroke on one side to the work stroke on the other side in the work area. Conventionally, the light beams projected from the light beam projection means in each work process have not been particularly distinguished.

[0003]

When the work area is a sloping ground such as a river dike, for example, skidding occurs when turning at the end of the work stroke and transferring to the next adjacent stroke. As a result, the turning radius becomes abnormally large, and as a result, a phenomenon may occur in which the adjacent stroke is greatly exceeded and the next stroke is reached. In this case, the work vehicle automatically travels along the beam of light as the light receiving means detects the beam of light of that stroke. In other words, it means skipping one step that should be done.

The present invention has been made in view of the above circumstances, and an object thereof is to enable a work vehicle to accurately transfer to the next adjacent stroke at the end of the work stroke. is there.

[0005]

A work guiding apparatus using beam light according to the present invention directs a beam light for guiding from one end side to the other end side of a work stroke in each of a plurality of parallel work strokes. A beam light projection means for projecting is provided,
The work vehicle is provided with a light receiving means for receiving the light beam and a control means for controlling the work vehicle to automatically travel along a work stroke based on light receiving information of the light receiving means. There, the characteristic configuration, the beam light projection means, in each of at least adjacent work strokes of the plurality of work strokes, is configured to project the light beam by superimposing different identification information respectively, The control means is configured to determine the work stroke based on the identification information.

[0006]

According to the above characteristic construction, the light beams of a plurality of work strokes are projected in a state having information for stroke identification. When the work vehicle turns at the end of the work stroke and moves to the next work stroke, the control means of the work vehicle performs correct work to be performed next based on the information for identifying the light beam received by the light receiving means. Determine whether it is a stroke. Therefore, if the turning radius becomes abnormally large due to skidding, etc., and if the vehicle has jumped over adjacent strokes and reached the next stroke, the control means discriminates this and the previous stroke The control to return to will be executed.

The mode of projecting the beam light by superimposing the identification information is different from the case of superimposing the identification information on the beam light itself, such as modulating the beam light with the identification information. It includes a case where the projection method is changed, such as intermittently projecting at a cycle or scanning the light beam at a different cycle.
Further, the identification information does not necessarily have to be different for all work steps, and two types of identification information may be alternately used so that adjacent work steps can be identified.

[0008]

As described above, according to the present invention, the operation of the work vehicle turning at the terminal end of the work stroke and changing to the next adjacent stroke can be accurately performed based on the identification information. It was

[0009]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 2, a work vehicle 1 which is an unmanned mowing robot reciprocates along a linear work path 2 which is set in parallel in a work area AR at predetermined intervals. The work vehicle 1 includes a crawler traveling device 3 and a mowing device 4, performs a mowing operation while advancing along the work stroke 2, and turns to the adjacent work stroke 2 at the end of the work stroke 2.

A beam light projection means (hereinafter referred to as a laser projector) for projecting a laser beam as a beam light for guiding the work vehicle 1 to automatically travel as described above is provided on the ground side. . That is, as shown in FIG. 1, a plurality of laser projectors 5 for projecting the laser beam B1 from one end side to the other end side of the work process 2 are arranged side by side outside the work area AR along one side thereof. At the same time, a pair of laser projectors 6 for projecting a laser beam B2 for notifying the work vehicle 1 of the end of each work stroke 2 are installed. The laser projector 5 and the laser projector 6 have the same structure described later.

On the other hand, the work vehicle 1 has laser beams B1 and B2.
Light receiving sensors 8 and 9 are provided as light receiving means for receiving light. A pair of front and rear light receiving sensors 8 provided on the upper portion of the work vehicle 1 receives the laser beam B1 and obtains information for the work vehicle 1 to go straight along the laser beam B1. Also, work vehicle 1
The light receiving sensors 9 provided on the left and right side surfaces of the laser beam B
It is understood that the work vehicle 1 has reached the end portion of the work stroke 2 by receiving the light of 2.

As shown in FIGS. 1 and 2, the support frame 8a for supporting the pair of front and rear light receiving sensors 8 is pivotally attached to the vehicle body at the center of the vertical axis P as shown in FIGS. The orientation of the support frame 8a with respect to the vehicle body differs by 180 degrees depending on whether the traveling direction of the work vehicle 1 is a direction toward or away from the laser projector 5. That is, as the work vehicle 1 turns at the end of the work stroke 2 and moves to the adjacent stroke, the support frame 8a rotates 180 degrees around the vertical axis P, and the light receiving surface of the light receiving sensor 8 always emits laser light. It is directed to the direction of the machine 5.

The light receiving sensor 8 has a shape elongated in the vehicle width direction, and is constituted by arranging a plurality of (for example, 16) light receiving elements in the longitudinal direction. Laser beam B from the laser projector 5
When 1 hits the light receiving sensor 8, at least one (for example, 1 to 2) of the light receiving elements is in a state of detecting light.

Therefore, for example, the light receiving position in the longitudinal direction (vehicle width direction), that is, the positional deviation of the working vehicle 1 in the vehicle width direction with respect to the laser beam B1 is determined depending on which light receiving element from the end detects light. Can be detected. In addition, the difference between the light receiving positions of the pair of front and rear light receiving sensors 8 causes the laser beam B
It is possible to detect the inclination (direction deviation) with respect to. That is, as shown in FIG. 4, the light receiving positions (distance from the end) of the front and rear light receiving sensors 8 are set to X1 and X2, respectively.
If the distance from the edge to the center is X0, then ΔX = X0-
X1 and ΔS = X1−X2 are the position deviation and the heading deviation in the vehicle width direction, respectively.

As shown in FIG. 5, a control means (hereinafter referred to as a controller) 10 using a microcomputer is mounted on the work vehicle 1, and the controller 10 causes the light receiving sensor 8 to operate.
Based on the detection information of the position deviation ΔX as described above
And the azimuth deviation ΔS. Then, based on them, the steering control of the vehicle body is performed in the following manner to bring ΔX and ΔS close to zero. That is,
The work vehicle 1 is automatically driven along the work stroke 2.

The left and right crawler traveling devices 3 of the work vehicle 1 are
It is possible to change gears individually by the hydraulic continuously variable transmission 11. That is, the vehicle body is steered by the speed difference between the left and right crawler traveling devices 3. The controller 10
By changing the angle of the variable swash plate in the hydraulic pumps of the left and right continuously variable transmissions 11 individually via the speed changing motor 12, the speeds of the left and right crawler traveling devices 3 are controlled separately.

That is, based on the above-mentioned ΔX and ΔS, by referring to the pre-stored shift table, the respective operation amounts of the left and right speed changing motors 12 are obtained, and the speed is calculated based on the operation amount. The changing motor 12 is driven. As a result, the work vehicle 1 automatically travels so as to maintain a state in which the front and rear light receiving sensors 8 properly receive the laser beam B1, that is, a state in which the light receiving position is substantially at the center in the longitudinal direction of the light receiving sensor 8. To do.

As shown in FIGS. 1 and 3, the light receiving sensors 9 provided on the left and right side surfaces of the work vehicle 1 reach the end of the work stroke 2 and the laser beam B from the laser projector 6 is reached.
Since it is only necessary to receive 2 light, a sensor smaller than the light receiving sensor 8 is used. The controller 10 of the work vehicle 1 moves to the left or right 180 by stopping one of the left and right crawler traveling devices 3 based on a signal indicating that the left or right light receiving sensor 9 has received the laser beam B2.
Turn and move to the next work step 2. At this time, as described above, the support frame 8a of the light receiving sensor 8 is moved around the vertical axis P by 1
Rotate 80 degrees. As the light receiving sensor 8 receives the laser beam B1 of the next work step 2, the automatic traveling along the laser beam B1 is started.

As shown in FIGS. 2 and 3, the laser beams B1 and B2 projected from the laser projectors 5 and 6 are vertically scanned within a range of predetermined angles θ1 and θ2. This is so that the light receiving sensors 8 and 9 can reliably receive the laser beams B1 and B2 even when the work area AR is on an uneven ground and the work vehicle 1 moves up and down while traveling. Is.

The laser projectors 5 and 6 include a semiconductor laser device 13 which is a laser light source, a movable mirror 14 for reflecting a laser beam emitted upward from the laser light source in a direction substantially parallel to the ground, and a movable mirror 14. The galvanometer scanner 15 etc. which rock in an angle range are provided. As shown in FIG. 6, the movable mirror 14 is a galvano scanner 15
The galvanoscanner 15 is fixed to the rotating shaft 15a of the No. 3 and is driven by the AC voltage Vo applied by the drive circuit 16. Therefore, the movable mirror 14 swings around the axis Q. The frequency of the AC voltage Vo corresponds to the oscillation frequency of the movable mirror 14, that is, the scanning frequency of the laser beams B1 and B2,
The amplitude determines the swing angle of the movable mirror 14. If the swing angle of the movable mirror 14 is α, the laser beam B1,
The scanning angles θ1 and θ2 of B2 are 2α.

The scanning frequency of the laser beam B1 projected from the laser projector 5 is set to be different so that the work vehicle 1 (controller 10) can distinguish the adjacent work strokes 2. That is, as shown in FIG. 1, the scanning frequencies of the five laser beams B1 projected on the five work steps 2 are:
Alternately, f and 2f (for example, f = 50 Hz) are set. In other words, the laser projector 5 is configured to project the laser beam B1 by superimposing the work stroke identification information (scanning frequency).

The controller 10 of the work vehicle 1 can determine whether the current work stroke is an odd number or an even number based on the signal from the light receiving sensor 8. That is, it is determined whether the frequency is f or 2f based on (the average of) the repetition period in which the light receiving sensor 8 receives the laser beam B1. Thus, as described above, when turning 180 degrees to the left or the right to move to the next work step 2 at the end of the work step 2, the laser beam B1 newly received by the light receiving sensor 8 is the correct next work step. I am checking if it is 2 or not.

That is, as shown in FIG. 3, the work area AR
Is a sloping land such as a river embankment, when turning at the end of work stroke 2 and moving to the next adjacent work stroke 2, the turning radius becomes abnormal due to the occurrence of skidding. As a result of the increase, the adjacent stroke may be greatly exceeded and the next stroke may be reached, but the presence or absence of such an abnormal state can be detected by the above check. That is, the laser beam B received after turning
If the frequency of 1 is the same as that before the turning, it means that the abnormal state has occurred. In this case, appropriate processing such as returning to the previous work process 2 is executed.

The controller 10 of the work vehicle 1 is provided with a work stroke counter 10a, and the controller 10 receives the laser beam B2 each time the light receiving sensor 9 receives the laser light, that is, each time the end portion of the work stroke is detected. Decrement the value by 1. When the value of the work stroke counter 10a becomes zero, the work is finished. The initial value of the work stroke counter 10a is manually set by the dial type work stroke number setting means 17 before the work is started.

Other examples will be listed below. In the above embodiment, two kinds of scanning frequencies f and 2f are alternately used so that the adjacent work strokes can be identified, but different scan frequencies may be assigned to each work stroke. In other words, for example, the laser beams of five work steps are sequentially scanned at frequencies f1, f2, ...
The controller 10 of the work vehicle 1 determines which frequency, that is, which work stroke, based on the light reception information of the light receiving sensor 8. Therefore, it is possible to easily determine the final work process from this information.

In the above embodiment, a pair of laser beams B for notifying the work vehicle 1 of the end of each work stroke 2.
For 2 as well, the scanning frequency may be different so that the controller 10 of the work vehicle 1 can determine which side the end portion is based on the light receiving information of the light receiving sensor 9.

The means for projecting the laser beam by superimposing the information for identifying the work process is not limited to the one in which the laser beam is scanned at the set frequency by using the galvano scanner as in the above-mentioned embodiment. It may be one that scans at a set frequency using a mirror. Further, the identification information is not limited to the method of changing the scanning frequency, but the intensity of the laser beam may be changed at a set frequency (AM modulation), or the laser beam may be projected intermittently at a set cycle.

It should be noted that although reference numerals are given in the claims for convenience of comparison with the drawings, the present invention is not limited to the structures of the accompanying drawings by the entry.

[0029]

[Brief description of drawings]

FIG. 1 is a work vehicle and a guidance device therefor according to an embodiment of the present invention;
And working area plan

FIG. 2 is a side view of the beam light projection means and the work vehicle.

[Figure 3] Rear view of the work vehicle

FIG. 4 is an explanatory diagram of a method of calculating a position deviation and a heading deviation of a work vehicle.

FIG. 5 is a control block diagram relating to traveling control of the work vehicle.

FIG. 6 is a diagram showing a means for scanning a light beam.

[Explanation of symbols]

 1 Work Vehicle 5 Beam Light Projecting Means 8 Light Receiving Means 10 Control Means

Claims (1)

[Claims] 1. A beam light projection means (5) for projecting a beam light for guiding from one end side to the other end side of the work stroke is provided in each of a plurality of work strokes parallel to each other.
Based on the light receiving means (8) for receiving the light beam on the work vehicle (1) and the light receiving information of the light receiving means (8),
A work guide device utilizing beam light, comprising: a control means (10) for controlling the work vehicle (1) to automatically travel along a work stroke, wherein the beam light projection means (5) is provided. In each of at least adjacent work steps of the plurality of work steps, different identification information is superimposed to project the light beam, and the control means (10) changes the identification information. A work vehicle guiding apparatus using light beams, which is configured to determine a work stroke based on the above.