JPH0241282B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for moving a reaping vehicle, specifically, a predetermined range of a working area, in a traveling order for a plurality of predetermined travel distances along a boundary between an untreated working area and a treated working area. sequence and a direction change sequence for moving the vehicle body 1 to the next stroke after completing one travel stroke, a pair of tracing sensors detecting the boundary and a detection result of the boundary by this sensor are used. The present invention relates to a reaping work vehicle that includes a control device on the vehicle body that controls a steering operation means based on the vehicle body.

Traditionally, this type of reaping vehicle, such as a lawnmowing vehicle, has been used to automatically perform ground work within a predetermined range of work area that has been treated as a pre-processed work area. The vehicle is divided into a plurality of travel strokes corresponding to the above, and control is performed to automatically travel while sequentially moving between the plurality of travel strokes.

In each of the above-mentioned travel steps, the sensor detects when the sensor has deviated from the boundary in order to automatically travel along this boundary based on the boundary detection result between the treated work area and the untreated work area in each process by the above-mentioned scanning sensor. When detected, steering control is performed to automatically correct the traveling direction so that the vehicle body aligns with the boundary by performing a steering operation in the opposite direction to the direction of the deviation.

However, the boundary detection is performed by detecting whether the running area is a treated work area or an untreated work area in the boundary detection part of the vehicle body, and for example, the boundary detection part of the vehicle body detects whether the driving area is a treated work area or an untreated work area. Even though the discontinuity of the boundary differs depending on the sparseness and density, the steering operation to align the vehicle body along the boundary was performed at a fixed steering angle that was patterned in advance. If the steering angle does not correspond well with the steering angle, for example, if the steering angle is set to a large value even though the objects to be harvested are dense, the tracking ability to the boundary will be poor, the vehicle will meander more, and the cutting If the steering angle is set small even though the objects are sparse, there is a risk that the vehicle will drive with ambiguous boundary detection and the vehicle body will deviate significantly from the actual boundary.

Therefore, in order to solve the above-mentioned drawbacks, it is possible to detect the sparseness and density of the object to be harvested at the start of each travel process, and then set the steering angle to suit the detection result while driving. Since the density of the objects to be harvested may be uneven and different in the traveling direction in the traveling direction, there is a drawback that depending on the traveling location, followability to boundaries is poor.

The present invention has been made in view of the above-mentioned practical applications, and provides a reaping work in which even when the density of objects to be harvested during the travel process is uneven, steering operations can be performed that suitably correspond to the density and density of the objects to be harvested. The purpose is to provide cars.

In order to achieve the above object, the reaping vehicle according to the present invention has the above-mentioned structure, and (a) is provided with a distance sensor that continuously detects the moving distance of the vehicle body.

(b) The control device includes a travel section setting means for setting a travel section into which the travel distance is divided into a plurality of sections.

(c) The control device is configured to collect information on the sparseness and density of the reaping target detected by the copying sensor located on the untreated work area side when the vehicle body travels through each travel zone set by the travel zone setting means. , is provided with a sparse/density state storage means for storing data for each traveling section.

(d) The control device stores a steering operation angle for aligning the vehicle body along the boundary when traveling in a travel stroke adjacent to the travel stroke stored in the sparse and dense state storage means. The vehicle is provided with a steering operation angle setting means for outputting an operation command signal for the steering operation means based on the density information for each traveling section stored in the means.

The characteristic configuration is that it has the configurations related to the points described in (a) to (d) above.

The functions and effects of this characteristic configuration are as follows.

That is, when traveling on one travel route, the sparseness and density of the object to be harvested is detected and stored for each travel section into which the travel route is divided into multiple sections, and when the vehicle travels on a travel route adjacent to that travel route, it is not stored. Based on the density information corresponding to each traveling section, the steering angle is set to align the vehicle body with the boundary. In response to this unevenness, it is now possible to perform appropriate steering control that corresponds to the sparseness and density of the object to be harvested, making it possible to improve the ability to follow the boundaries of the vehicle body.

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

As shown in FIG. 1, the front and rear wheels 2 and 3 of the vehicle body 1
A lawn mowing device 4 is suspended in the middle part of the lawn mower 4 so as to be movable up and down, and tracing sensors 5, 5 having the configuration described later are installed for determining the boundary L between the unmown area B and the mowed area C, which are the boundaries of the working area A. The mowing vehicle is provided on the front left and right sides of the vehicle body 1, and is configured as a mowing vehicle that can automatically travel along a predetermined travel course by being steering controlled based on the detection results of the boundary L by the tracing sensors 5, 5.

Further, the vehicle body 1 is provided with a fifth wheel 6A as a distance sensor 6 that generates a predetermined number of pulse signals per unit travel distance _l0 in order to continuously detect the travel distance l of the vehicle body 1, In order to detect the orientation (azimuth) of the vehicle body 1, a geomagnetic sensor is provided as an azimuth sensor 7, which detects the azimuth by detecting changes in the strength of the earth's magnetic field.

Incidentally, the wheels 2, 2 and the rear wheels 3, 3 are both configured to be able to be operated by steering.
By steering the front and rear wheels 2 and 3 in the same direction, the vehicle body 1 moves in parallel without changing its orientation, and at the same time, the front and rear wheels 2 and 3 are steered in relatively opposite directions. This allows it to turn with a very small turning radius.

The scanning sensor 5 includes two optical sensors S ₁ ,
The optical sensors S ₁ and _{S 2}
As shown in FIG. 2, U-shaped sensor frames 9 and 9 are attached to the vehicle body 1 at the distal ends of the support frame 8 whose base end is fixed to the lawn mower 4.
Light emitting elements P ₁ are arranged adjacent to each other in the left and right direction, and light emitting elements P 1 are respectively arranged on the inner facing surface of this sensor frame 9.
and a light-receiving element _P2 are provided as a pair, and by sensing the presence or absence of grass passing between the light-emitting element _P1 and the light-receiving element _P2 , it is possible to distinguish between an unmowed area B and a mown area C. It is configured as expected. Note that the copying sensor 5 is not limited to those using optical sensors S ₁ and S ₂ ;
It may be constructed from any type of sensor, including contact type and non-contact type.

The light receiving elements P ₂ of the optical sensors S ₁ and S ₂ ,
The discrimination signal between the unmowed area B and the mown area C obtained from _P2 becomes a discontinuous pulse-like signal because the grass passes intermittently. Therefore, after performing an integral process to convert into a continuous discrimination signal, the control device 1 described later
It is configured to input 0.

To integrate the output signal _C1 of the light receiving element _P2 , as shown in FIG. 3, the number of output pulses of the distance sensor 6 is counted and a carry signal _C1 is generated every preset count value _N0. A programmable counter 11 that outputs an output signal and a flip-flop 12 that is reset by the carry signal C ₂ ' of this counter 11 are provided, and the output signal of the light receiving element P ₂ is
_C1 is configured to reset the counter 11 and set the flip-flop 12, and the counter 11 and flip-flop 12 constitute a digital filter 13.
Discrimination signals C ₀ of continuous boundaries L corresponding to the states of the unmown land B and the mowed land C are obtained.

The operation of this digital filter 13 will be briefly explained below.

The counter 11 is repeatedly reset by the output pulse signal _C1 of the light receiving element _P2 regardless of the counter value N, and the flip-flop 12 is set. Then, when the grass disappears, this pulse signal _C1 becomes "L" level, and after traveling a predetermined distance _l0 , the counter 11 reaches the count value _N0 corresponding to this predetermined distance _l0 , and the distance sensor 6 The counter 11 outputs the carry signal C ₂ only when the output signal C ₃ is counted, and the flip-flop 12 is reset. Therefore, the output of the flip-flop 12 is a discrimination signal that continuously repeats the "H" level corresponding to the grass detection state, that is, the detection of unmowed land B, or the "L" level corresponding to the grassless state, that is, the detection of mowed land C. C ₀ is obtained.

Hereinafter, a control system for controlling the travel of the lawn mowing vehicle based on the parameters detected by the tracing sensors 5, 5, distance sensor 6, and direction sensor 7 configured as described above will be described.

As shown in FIG. 3, the control system has signals from the sensors 5, 5, 6, and 7 inputted to a control device 10 whose main part is a microcomputer. 5,
Hydraulic cylinders 14 and 15 are provided for steering operation of the front and rear wheels 2 and 3, respectively, in order to automatically control the running direction and running speed of the vehicle body 1 by processing the detected parameters 5, 6, and 7. The control signal is configured to generate control signals that drive actuators such as electromagnetic valves 16 and 17 that operate the hydraulic continuously variable transmission 18 and a motor 19 that operates the shift position of the hydraulic continuously variable transmission 18.

In addition, here, front wheel 2, rear wheel 3, hydraulic cylinder 1
4, 15, electromagnetic valves 16, 17, hydraulic continuously variable transmission 18, and motor 19 constitute steering operation means.

Further, as will be described later, the control device 10 is provided with a travel section setting means for setting a plurality of travel sections _Ls into which the predetermined travel distance is divided, and each travel section _Ls set by the travel section setting means is set by the vehicle body. When the robot 1 runs, the grass density information detected by the tracing sensor 5 on the untreated work area side is transmitted to each traveling section.
comprising a sparse/density state storage means for storing each l _s , and
The steering operation angle θ for aligning the vehicle body 1 along the boundary L when traveling in a travel stroke adjacent to the travel distance stored in the sparse/concentration state storage means is set for each of the travels stored in the sparse/concentration state storage means. section
The apparatus is configured to include a steering operation angle setting means for outputting an operation command signal for the steering operation means, which is set based on the density information for each l _s .

In FIG. 3, R ₁ and R ₁ are potentiometers for detecting the actual steering angles of the front and rear wheels 2 and 3 and providing feedback to the control device 10.
_R3 is a potentiometer that similarly detects the shift position of the transmission 18.

Hereinafter, based on the detection results of the boundary L by the scanning sensors 5, 5, the steering operation angle θ and the integral time constant τ of the digital filter 13 when the vehicle body 1 automatically travels along the boundary L, that is, the programmable counter 11... A means for automatically setting the count preset value according to the condition of the work area A, that is, the density of the grass will be explained.

As shown in FIG. 4, each travel stroke is divided into a plurality of predetermined sections _Ls , and while driving in each section _Ls , the discrimination signal from one of the scanning sensors 5 on the uncut land B side is received. By repeatedly sampling the state changes of C ₀ and detecting the density and density of the grass in the section l _s that is currently being traveled, when driving in the same section l _s on the next trip,
Based on the detection result of the sparse/concentrated state, the steering operation angle θ and the preset value of the counter 11 are automatically changed.

That is, the case where the combinations of the boundary discrimination signals C ₀ and C ₀ from the two optical sensors S ₁ and S ₂ constituting the scanning sensor 5 on the uncut land B side are "H" and "H" is the above case. If the number of samplings in the predetermined section l _s is equal to or greater than a predetermined ratio (for example, 80%), it is determined that the grass is dense, and at least one of the two optical sensors S ₁ and S ₂ is “L”. If the number of samplings exceeds a predetermined ratio (for example, 50%), it is determined that the grass is sparse, and in other cases, it is determined that the grass is in a normal intermediate state.

The steering operation angle .theta. and the preset value of the counter 11 are automatically changed to the values described below in accordance with the result of determining whether the grass is dense, medium, or sparse.

The steering operation angle θ is set to be a large angle θ ₁ , for example, about 10 degrees, in both directions of the unmowed area B and the mowed area C when the grass is dense;
In the middle, when operating in the direction of uncut land B, the angle θ ₂ is larger than the above-mentioned large angle θ ₁ , for example, 15 degrees, and when operating in the direction of the mowed land C, the angle θ is slightly smaller than the above-mentioned large angle θ ₁ . ₁ ', for example, 8 degrees, and if the grass is sparse, the angle θ ₃ is larger than the above-mentioned angles θ ₁ and θ ₂ , for example, 20 degrees, in the direction of the unmowed area B. In the direction, the smallest angle θ ₃ ', for example 7 degrees, is set to correspond to each determination result for each steering operation.

Similarly, the preset value of the counter 11 is set so that the integral time constant τ is shortened when the grass is dense, and becomes long when the grass is sparse, so that the preset value of the counter 11 is switched in three stages corresponding to each determination result. It is set as.

By the way, the reason why the steering operation angle θ is not the same in the direction of the unmowed area B and the mowed area C when the grass is not dense is to improve the tracking convergence with respect to the boundary L.

The steering angle θ and the time constant τ, which is a preset value of the counter 11, corresponding to the result of determining the density of the grass are stored in advance in a table form in the control device 10, as shown in FIG.

Incidentally, FIG. 6 is a flowchart showing the operation of the control device 10 described above.

Further, the settings of the steering operation angle θ and the integral time constant τ corresponding to the grass density determination result may be further subdivided in addition to the tabled values shown in this example, or may be set continuously by calculation etc. It may be configured to be set automatically.

Incidentally, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of drawings]

The drawings show an embodiment of the automatic driving vehicle according to the present invention, in which FIG. 1 is an overall plan view of the lawn mowing vehicle, FIG. 2 is a front view of the main parts of the scanning sensor, and FIG. 3 is a block diagram of the control system. FIG. 4 is an explanatory diagram of work place state detection, FIG. 5 is a table of control parameters, and FIG. 6 is a flowchart showing the operation of the control device. 5... Copying sensor, 6... Distance sensor, 1
0... Control device, B... Untreated work area, C... Treated work area, L... Boundary, l... Travel distance, l _s ...
...Traveling section, θ...Steering operation angle.

Claims (1)

[Scope of Claims] 1. A travel order sequence for a plurality of predetermined travel distances in a predetermined range of work areas along a boundary L between an untreated work area B and a treated work area C;
A pair of copying sensors 5, 5 detecting the boundary L and a boundary formed by the sensors 5, 5 in order to automatically travel based on a direction change sequence for moving the vehicle body 1 to the next stroke after completing one travel stroke. A reaping work vehicle characterized in that the vehicle body 1 is equipped with a control device 10 that controls a steering operation means based on the detection result of L, and the following configurations (a) to (d) are provided. (a) A distance sensor 6 is provided to continuously detect the moving distance l of the vehicle body 1. (b) The control device 10 is equipped with a travel section setting means for setting a plurality of travel sections _ls into which the travel stroke is divided into a plurality of sections. (C) The control device 10 is configured to control the scanning sensor 5 on the side of the untreated work area B to detect when the vehicle body 1 travels through each travel zone set by the travel zone setting _means . The vehicle is provided with a sparse/density state storage means for storing sparsity/density information of the reaping target for each _of the traveling sections Is. (d) The control device 10 determines a steering operation angle θ for aligning the vehicle body 1 along the boundary L when traveling in a travel stroke adjacent to the travel stroke stored in the sparse/dense state storage means. Each of the travel sections stored in the sparse/dense state storage means
A steering operation angle setting means is provided for setting an operation command signal for the steering operation means based on the density information for each l _s .