JPS6366162B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an automatic traveling reaping work vehicle, and more specifically, a scanning sensor consisting of a plurality of sensors for detecting uncut materials arranged in parallel in the left and right direction is provided on both the left and right sides of the vehicle. In addition, the following scanning sensor on one side includes means for steering the steering wheels based on a combination of output signals from both of the scanning sensors so that the machine travels along the boundary between the mown field and the uncut field. Regarding a self-driving lawn mower.

Although it is possible for such lawn mowers to automatically travel along the boundary between unmowed and mown fields,
In this case, although it is possible to perform so-called circular mowing, where the grass is mowed inward while going around the perimeter of the uncut area, the lawn mower starts from one side of the uncut area and runs back and forth parallel to that side. It was impossible to automatically perform the so-called reciprocating mowing when reaching the other side.

However, mowing the lawn is not just about mowing; the aesthetic appearance after mowing, in other words, how the mowing marks look, is an important issue. There is a strong demand for mowing.

In view of these circumstances, it is an object of the present invention to provide a lawn mower that can automatically perform reciprocating mowing, and when neither of the two tracing sensors detects uncut grass, The present invention is characterized in that means is provided for steering the steering wheel toward the uncut land side based on the order of the combination of output signals of the two sensors, and for switching the scanning sensor that should follow the boundary.

According to this characteristic configuration, the machine travels along the boundary between the uncut field and the cut field using the scanning sensor on one side, and when it reaches the edge of the uncut field in the traveling direction, the machine
The lawn is automatically turned to the unmown side, but at this time, the scanning sensor that should detect the boundary is switched from one side to the other, so that the unmown area and the already mowed area that were created by the previous mowing are separated. The aircraft will be automatically turned until the switching sensor is aligned with the new boundary. This tracing sensor automatically steers the lawn mower along the new boundary between the unmown area and the mowed area created by the previous lawn mowing. Therefore, it has been possible to perform automatic lawn mowing work with extremely good reciprocating mowing on lawns where the surrounding area has been artificially cut in advance, or where the surrounding area is originally a ground surface with no grass or the like. It is.

It is now possible to mow reciprocatingly by automatic driving.

An embodiment of the present invention will be described below.

FIG. 1 is a drawing showing the procedure for mowing a lawn by an automatic mowing lawn mower, which is an example of an automatic mowing vehicle of the present invention. Reaping work is carried out in advance, and the entire outer peripheral area 2 is used as already cut land for turning the aircraft.
Next, the unmown lawn area 3 inside the outer circumferential turning area 2
The lawn mower 4 is continuously automatically steered according to a predetermined turning direction while automatically determining the boundary between the mowed field and the unmown field using the left and right copying sensors 5 and 6 (described later), and performs reciprocating mowing. This allows the automatic reaping work to be carried out by

FIG. 4 is a hydraulic circuit diagram for steering the steering wheels 15, 15, which are the front wheels.
A hydraulic cylinder 16 for steering the engine 15 is connected to a hydraulic pump 19 via a solenoid valve 17 and a branch valve 18. The branch valve 18 always branches and sends a constant amount of oil to the electromagnetic valve 17, and the electromagnetic valve 17 changes the flow path of the oil flowing to the hydraulic cylinder 16 by moving the valve body when the left and right solenoids are activated.

FIG. 2 is a drawing showing an embodiment of the copying sensors 5 and 6, in which a pair of left and right opposed optical sensors 7,
According to 8, 9, and 10, if uncut grass is not detected,
A pair of left and right opposed optical sensors 7, 8 and 9 are used to determine whether the field is mown or unmown by generating a LOW level signal and a HIGH level signal when detecting uncut grass. , 10 are placed side by side on both the left and right sides of the machine to form scanning sensors 5 and 6, respectively.

When traveling along the boundary between an unmowed field and a mowed field, the optical sensor 8 or 9 near the center of the machine detects uncut grass, and the other optical sensor 7 or 10 does not detect uncut grass. The aircraft is steered to meet this standard.

FIG. 3 shows the pair of left and right scanning sensors 5,
6 is a circuit diagram illustrating an embodiment of an automatic travel control device that automatically controls turning direction and tracing travel by inputting a signal indicating whether the field is a mown field or an unmown field detected by 6. 4 tracing light sensors 7, 8,
4 to invert each signal logic from 9 and 10
A turning direction control circuit 11 which receives NOT circuits N ₁ to _{N 4} and the outputs of the NOT circuits N ₁ to _{N 4} and the outputs of the optical sensors 7 to 10 as appropriate inputs and controls the turning direction.
, a tracing traveling control circuit 12 that controls tracing along the boundary between uncut grass and cut grass while traveling, and left-right steering output from the traveling control circuit 12 and the turning direction control circuit 11, respectively. It is composed of two OR circuits G ₁ and G ₂ that receive control signals as inputs, and left and right steering solenoid circuits 13 and 14 that are driven by the logical outputs of the OR circuits G ₁ and G ₂ .

The turning direction control circuit 11 outputs a logic output indicating the state of the lawn 3, that is, HIGH when all the four optical sensors 7 to 10 are on the turning area 2.
A first AND circuit G ₁₁ that outputs a level, a second AND circuit G ₁₂ that outputs a HIGH level when the lawn mower 4 is adjacent to a mowed field on the left, and A third AND circuit _G13 outputs a HIGH level when mowed land is adjacent to the ground, and the second
Input the output of AND circuit _G12 to reset terminal R,
The output of the third AND circuit _G13 is input to the set terminal _S , and the flip-flop F1 generates a pair of logic outputs _Q1 , ₁ , and the outputs Q1, ₁ of the flip-flop F1 are connected to one of the flip-flops _F1 and ₁ , respectively. It is composed of two two-input AND circuits G ₁₄ and G ₁₅ whose input is the output of the first AND circuit G ₁₁ and whose other input is the output of the first AND circuit G 11 .

If you want to turn leftward, use the above AND circuit.
A HIGH level signal is output from _G14 to the left steering solenoid circuit 13 via the OR circuit _G1 , and when turning to the right, the AND circuit _G15 is output.
Therefore, a HIGH level signal is output to the right steering solenoid circuit 14 via the OR circuit _G2 .

Similar to the turning direction control circuit 11, the copying travel control circuit 12 includes an AND circuit G ₂₁ that outputs a HIGH level when only the optical sensor 7 is on the already mowed field.
and when only the optical sensor 10 is in the already mowed field
An AND circuit G ₂₂ that outputs a HIGH level, an AND circuit G _{23 that outputs a HIGH level when all optical sensors are on an unmowed area, and an AND circuit G 23} that outputs a HIGH level when the right scanning sensor 5, that is, optical sensors 7 and 8 are on an already mowed area.
An AND circuit G ₂₄ that outputs a HIGH level, an AND circuit G ₂₅ that outputs a HIGH level when the left scanning sensor 6, that is, the optical sensors 9 and 10 are on a mown field, and the output of the AND circuit G ₂₁ are connected to a set terminal S. , the output of the AND circuit G ₂₂ is input to the reset terminal R, the output of the first AND circuit G 11 of the turning direction control circuit ₁₁ is input to the trigger input terminal T, and a pair of logical outputs are input. A flip-flop F ₂ that generates Q ₂ , ₂ and the output Q ₂ , ₂ of the flip-flop F ₂ are used as one input, respectively, and the above
Two circuits with the output of AND circuit G ₂₃ as the other input
AND circuits G ₂₆ and G ₂₇ , and an OR circuit G ₂₈ and the AND circuit each having one input as the output of the AND circuits G ₂₆ and G ₂₇ and the other input as the AND circuit G ₂₄ .
It is composed of an OR circuit _G29 whose other input is _G25 .

Therefore, when the lawn mower 4 runs adjacent to the mowed field on the right side, the light sensor 7
Since the optical sensors 8 to 10 output a LOW level and the optical sensors 8 to 10 output a HIGH level, only the third AND circuit _G13 outputs a HIGH level, and the other first and second
Since the AND circuits G ₁₁ and G ₁₂ all output LOW level, the flip-flop F ₁ is set, the output Q ₁ becomes HIGH level, and the output ₁ becomes LOW level.

On the other hand, when the lawn mower 4 runs adjacent to a mowed field on the left side, the light sensor 10 is set to LOW.
Since the level sensors 7 to 9 output a HIGH level, only the second AND circuit _G12 outputs a HIGH level, and the other first and third AND circuits output a HIGH level.
Since G ₁₁ and G ₁₃ all output LOW level, the flip-flop F ₁ is reset and the output
Q ₁ becomes LOW level and output ₁ becomes HIGH level.

However, as mentioned above, no matter which state the outputs Q ₁ and ₁ of the flip-flop F ₁ are in, the output of the first AND circuit G ₁₁ is at the LOW level, so the two two-input AND circuits
Since G ₁₄ and G ₁₅ are both closed and output a LOW level, neither of the solenoid circuits 13 and 14 is activated, and the lawn mower 4 moves straight.

Next, when the lawn mower 4 enters the turning area 2, the optical sensors 7 to 10 all output LOW level, so the first AND circuit _G11
Outputs HIGH level and connects the above two AND circuits
G ₁₄ and G ₁₅ are opened and the state of the preset outputs Q ₁ and ₁ of flip-flop F ₁ when driving straight as described above, that is, when driving with a cut field adjacent to the right side, the left In order to perform steering, the left steering solenoid circuit 13 is activated by the output _Q1 which is at HIGH level,
If you are driving with an already mowed field on your left side, turn the HIGH
The right steering solenoid circuit 14 is operated by the output ₁ which is at the level, and the lawn mower 4
automatically turns in the correct direction at turning point 2.

Next, when the lawn mower 4 changes its strike direction as described above and enters the unmowed area of the lawn 3, one of the optical sensors 7 to 10 outputs a HIGH level, so that the first The output of AND circuit _G11 is
The level becomes LOW, the two 2-input AND circuits G ₁₄ and G ₁₅ are closed, and the solenoid circuit 1
3 and 14 both stop operating, and the lawn mower 4 becomes neutral and moves straight.

By the way, the lawnmower 4 moves straight after changing direction at the turning area 2, but if it continues as it is, it will go straight diagonally through the unmowed area and into the already mowed area, so the optical sensors 7 to 10 Of these, a pair of copying sensors 5 or 6 is
When the LOW level is detected, the travel control circuit 12 operates the left and right steering solenoid circuits 13 and 14 to steer the vehicle in the opposite direction to the direction in which the direction was changed at the turning point 2, and the light at the right end is activated. Only the sensor 7 or the leftmost light sensor 10 is in the mowed field, that is, the LOW level, the other sensors 8, 9, 10 or 7, 8, 9
are all unmowed areas, that is, the AND circuit G ₂₄ of the travel control circuit 12 outputs a HIGH level.
G ₂₅ or the AND circuit of the turning direction control circuit 11
By inverting the state of flip-flop F ₂ by the output of G ₁₁ every time the lawn mower 4 enters the turning area 2, the steering is controlled and the mower always moves to the unmown area adjacent to the mowed area on either the left or right side. The robot moves automatically to mow the lawn.

The automatic travel control device illustrated in FIG. 3 inputs logic signals indicating uncut grass and cut grass detected by a pair of left and right tracing sensors 5 and 6 to a computer such as a microprocessor, The steering electromagnetic valve 17 may be controlled according to a pre-stored program, so the present invention is not limited to the embodiments illustrated.

In addition, as shown in FIG. 5, each optical sensor 7,
8, 9, and 10 are equipped with an integrator b for waveform shaping on the receiver a side, and instead of reacting to each individual grass, the average value over a predetermined time is output as a signal. It is something that

[Brief explanation of drawings]

The drawings illustrate embodiments of the automatic traveling reaping vehicle according to the present invention, and FIG. 1 is a drawing showing the reaping procedure;
Fig. 2 is a drawing showing an example of a scanning sensor, Fig. 3 is a drawing showing an example of an automatic travel control device, Fig. 4 is a hydraulic circuit diagram for steering, and Fig. 5 is a signal processing circuit diagram of the sensor section. It is. 5, 6... Copying sensor.

Claims (1)

[Claims] 1 Copying sensors 5 and 6 consisting of a plurality of sensors for detecting uncut objects arranged in parallel in the left and right direction
are provided on both the left and right sides of the machine body, and the copying sensors 5 and 6 on one side control the output signals from both of the copying sensors 5 and 6 so that the machine travels along the boundary between the cut field and the uncut field. In the automatic traveling mowing vehicle equipped with a means for steering steering wheels based on the combination, when neither of the two tracing sensors 5, 6 detects uncut grass, the two sensors 5, The automatic traveling reaping work is characterized in that the steering wheel is steered toward the uncut land side based on the order of the combination of the output signals of No. 6, and means is provided for switching the scanning sensors 5 and 6 to follow the boundary. car.