JPH01206412A - Guide for mobile working vehicle - Google Patents

Abstract

PURPOSE:To improve adaptability with respect to the unevenness of ground by measuring the distance from a mobile working vehicle to a reference point by means of an ultrasonic wave. CONSTITUTION:A couple of ultrasonic wave oscillators 3 and 4 are arranged near the side edges of the right and left sections of the reciprocating direction of a working section 1 with setting a reference line (c) to cross with respect to the reciprocating direction. A couple of ultrasonic wave oscillators 3 and 4 are caused to alternately generate the waves with providing a specified time difference, and a distance-measuring device 5 provided on the working vehicle 2 receives the waves, whereby the distances between the mobile vehicle 2 and respective ultrasonic wave oscillators 3 and 4 are measured. The position of the working vehicle 2 is decided from a triangle in which the know distance between the ultrasonic wave oscillators 3 and 4 is set to the base.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a guidance device for a mobile working vehicle, and can be used for straight-line control of mobile agricultural machinery such as tractors, unmanned operation, etc.

BACKGROUND TECHNOLOGY AND PROBLEMS TO BE SOLVED BY THE INVENTION Conventionally, in a rectangular work zone of known size, markers are placed at multiple locations around the perimeter, and the distances between these PA markers are measured to determine the known size. A work T::I that moves within the work area.
There was a method that measured the azimuth angle of these signs from rt, and detected the position of the mobile work vehicle from a triangle with one known side and the measured two angles, but the calculation was complicated and optical Direction measurement has the disadvantage that it is difficult to recognize signs when the vehicle is rolling or pitching.

Means for Solving the Problems This invention provides a pair of ultrasonic transmitters ( 3) and (4) are provided so that they transmit alternately with a certain time difference, and a line (a) connecting this pair of ultrasonic transmitters (3) and (4) is perpendicular to the one. Moving work that progresses the work in the direction of ・l'+:
(2) is equipped with an ultrasonic distance measuring device (5) capable of detecting distance by receiving ultrasonic waves, and each ultrasonic transmitter (3)
and (4) the ultrasonic transmitter and the ultra i'f wave ranging device (5
), the moving position 71 of the mobile work vehicle (2) is measured while measuring the distance between these correct positions.
(b) A guidance device for a mobile work vehicle is configured to detect the following.

Functions and Effects of the Invention For example, in a diagonal work area (1), when the mobile work vehicle (2) is turned around along the long sides and the work is carried out from one side to the other by repeating back and forth movements, the work Section (1)
The length of the long side and the distance of the short side can be measured in advance and can be known values. In addition, it is also possible to measure the actual working width of the mobile work vehicle (2) moving straight along the long side. Set the correct position of the base along the assumed line and install a pair of sonic wave transmitters (3) and (4), then the distance between each of these transmitters (3) and (4) is can also be measured and made into a known value.

Furthermore, the known distance between the pair of ultrasonic transmitters (3) and (4) is determined by the moving operation 1j (2) 1! :11A in width
The line connecting each ultrasonic transmitter (3) and (4) (
A) and the mobile work vehicle (2) are orthogonal to the scheduled course.

In this way, when the mobile work vehicle (2) is, for example, a tractor equipped with a rotary rotary device, the ultrasonic distance measuring device (5) can be installed on the tractor part corresponding to the center position of the plowing width. Since this ultrasonic distance device (5) can be made to follow the planned course, the work area (1)
At the start position of the - end of the ultrasonic transmitter (3
) and (4) are received and the distance is measured, the base is ff1 (a) connecting the TFL sound wave transmitters (3) and (4), and the distance measuring device (5) is ) position as the apex and the length of the three sides is known, and furthermore, the intersection point where the word line (a) and the planned course intersect perpendicularly and the distance measuring device of the mobile work vehicle (2) can be detected. (5) Since it can be divided into left and right right triangles by the line connecting the work vehicle (2
) and the calculation of this right triangle, it is possible to easily detect deviations to the left or right from the planned course. Based on this detection result, the position can be corrected by controlling the steering of the mobile work vehicle (2), and the planned course can be corrected. You can control the progress according to the following. As progress progresses, the transmitters (3) and (4) are connected! la(
b)] When reaching 2, it can be detected that the height of the triangle or right triangle for the above calculation becomes zero,
Moreover, the distance between the ultrasonic transmitter (3) on the minus side and the ultrasonic transmitter (4) on the other side can also be actually measured. When setting the scheduled course, this scheduled course and left and right firing (3) and (4)
The position of each course of L and 1 can be calculated and set, so the distance from the left or right transmission ``A (3) or (4) in lia. By actually measuring, it is possible to detect left and right deviations from the planned course.
, the ultrasonic δIII distance device (5) of the mobile work jE (2) moves forward with each transmitter 5A (3) and (4) positioned in relation to the rear left and right, but the triangle for calculation is This is the same as in 1iii above, and the movement position (b) can be easily detected.

In the case of an irregularly shaped work area (1), this work area (1)
) is the longitudinal direction of the work, since it requires fewer turns and is efficient and common.
Install the fll wave nail signal 3) (4), measure these distances, and set a planned course by dividing it into the corresponding working width.For example, start reciprocating work from the right side and then move to the left side sequentially. When doing so, use the position of the ultrasonic transmitter (3) on the left as a reference point, set the distance from here to the intersection of the planned course and the word line (A), and set the position of the transmitter (3). With the origin as the origin, the word line (a) connecting the transmitters (3) and (4) is X
Determine the coordinates of the Y-axis in the direction perpendicular to the X-axis passing through the axis and the origin, and then determine the position in XY coordinates of the point where the periphery of this section [1] intersects with the starting and ending ends of each scheduled course. After teaching and memorizing the mobile work vehicle (2) by rotating it around the site, I was able to confirm the starting and ending positions for following the planned course. )
It is possible to guide the work vehicle while measuring the distance to and (4) and detecting the position (b) of the work vehicle (2).

To determine the transmission of a pair of ultrasonic transmitters (3) and (4), for example, if both transmit pulses at intervals of one second, one transmitter (3) must be connected to the other transmitter. By delaying the transmission pulse in (4) for, for example, h seconds, a pulse interval of h seconds and 5 seconds occurs during copulation, so the front signal between the h seconds interval is transmitted by the transmitter (3), and the rear signal is transmitted by the transmitter (3). is the transmitter (4)
In addition, by making the distance measuring device (5) reserve this transmission timing, etc., the distance measuring device (5) can receive different distances in a detectable manner.

In this way, by transmitting pulses from the two ultrasonic transmitters (3) and (4) with a certain time difference,
The receiver of one ultrasonic distance measuring device (5) can easily detect one separate distance without providing separate frequencies of &Ba waves, and the device can be simplified. In addition, an ultra FF wave oscillator (
3) By using (4) as the reference point for detecting the moving position (b) of the mobile work vehicle (2), the distance to the reference point can be detected, which requires fewer detection steps than when measuring the azimuth using light or radio waves. , (This has the effect of making an inexpensive guidance device.

Embodiment In the case of turning, the rectangular work section (1) is a rectangular work section (1), and as shown in FIG. 1 and FIG. The distance (L) of the short side and the distance #(W) of the short side are the known distances, and the total is δ11.The mobile work type (2) is moved along the long side and repeatedly turned back and forth from the right side to the In primary left side. This example shows a case where moving work is performed.

The mobile work vehicle (2) is an example of a tractor (2) with a rotary tiller 21 (7) attached to the rear.
is a pair of driven front wheels on the left and right that can be steered freely (
8) and a driving rear wheel (9) with a steering handle (10).
) with I#! The vertical chamber is constructed by submerging a cabin (11), and an ultrasonic transmitter 21 is installed on the roof of the cabin (11).
(5) is provided. In addition, there is also a shaft (14) on which the steering angle of the steering arm (13) of the steering mechanism (12) connected to the handle (lO) can be measured.
is provided with a steering angle sensor (15), and a hydraulic cylinder (16) is installed between the steering arm (13) and the vehicle body (c) of the mobile work vehicle (2),
By expanding and contracting this hydraulic cylinder (16),
R provided at the end of the rod (+7) and king pin (18)
, (+9), the front wheels (8) (8>) can also be steered.

Ultrasonic transmitters (3) and (4), which are used as measurement points, are mounted on columns (20 ), and this support +)(2
0) The ultrasonic side 'A' of the mobile work vehicle (2) located at the start and end of the work progress direction (d) above! The device (5) is provided so that it can transmit signals within a detectable range. 1tfl sound wave is 7~
L is about 0KH2, but it is not limited to this, and the long side distance (L) is about 50-1001'1, but it is not limited to this, and the base points (3) and (4) are The transmission from each ultra-FF wave transmitter is repeated with a slight time difference. In addition, the short side distance (W) of one work section (1) is the distance between the left and right T8TF wave transmitters (3) and (4), and the line connecting (3) and (4) is the reference line. (A), and this reference line (A) is set so as to be perpendicular to the left and right long sides (L) and the planned course (E).

The ultrasonic ranging device (5) is composed of an ultrasonic transmitter (5A) and a detection control circuit (5B) including a computer (CPU).

Ultrasonic transmitters (3), (4) and ultrasonic ranging device (5)
The control configuration based on the transmission and reception of each ultrasonic wave transmitter 'A(3) and (4) is as shown in the control blow diagram of FIG.
) to transmit the ultrasonic waves from the ultra RF receiver J8 (5A
) is received and input to the computer (cpU),
The configuration is such that a communication signal is sent from the computer (CPU) to the ultra FF wave transmitters (3) and (4) via the communication unit (21), and the computer (CPU) uses this information to send communication signals to each transmitter. (3) When the distance to (4) is detected and deviation from the planned course (e) to the left or right is detected, the steering angle sensor (15) adjusts the planned steering angle according to the size of the deviation. From the hydraulic pump (P) and pressure oil tank (T) to the solenoid valve (
22), the solenoid valve (22) of the hydraulic circuit that operates the hydraulic cylinder (1B) is operated, and the front wheels (8) of the mobile work vehicle (2) are operated to steer the mobile work vehicle (2). This configuration controls the return to the scheduled course (e).

Ultrasonic transmission! If (3) and (4) are used, the ultrasonic ranging device (5)'s 8￥f wave receiver (5A) and detection control circuit (5
The transmission and reception operations to B) are explained by the example shown in FIG. A waveform is generated at a set timing, and then the carrier wave oscillator modulates the waveform with a carrier wave, which is amplified and transmitted. Ultrasonic transmitter (
The same is true on the 4) side, but the waves from each of the oscillators (3) and (4) are transmitted with different timings even though the frequency and length are the same. This transmission timing is reserved on the receiver (5A) side. Ultrasonic waves with shifted timing from each of these transmitters (3) and (4) are transmitted to the receiver (5) of the range device (5).
A), pulse detection is performed, and the signal is input directly to the computer (CPU) and is also held in the latch register.

In this latch register, the clock pulse from the clock oscillator is input to the timer counter, and the clock pulse from the clock oscillator is input to the timer side.
Then, the time from transmission to reception from each of the transmitters (3) and (4) that has been contracted is measured, and the time is input from the latch register to the computer (c p u).
U) calculates and detects the distance to each transmitter (3) and (4), further detects the deviation distance from the planned course (e), and outputs the steering operation of moving work 11 ((2)). It is something.

As shown in Fig. 7, the ultrasonic transmitters (3) and (4) and the ultrasonic ranging device (5) are each equipped with an evening/imma counter, and the reset timing of the timer counter is determined by the same clock. If the transmitter (3) and (4) are input to the external reset output (to) of the receiving device, the three timer counters will be synchronized to the zero order transmitter (3). ) and (4), the timing of pulse transmission is set separately for the transmitters (3) and (4), and the computer (c p u) of the distance measuring device (5) is set in advance. Once programmed, (cpu) will transmit transmitters (3) and (4).
) The counter data is latched (held) by detecting the received pulse in order to know when the primary ultrasonic pulse was received, which predicts the timing of the pulse transmission.
Read this and get the time uI from sending to receiving.
I can be calculated. In this way, the distance is then calculated by dividing the calculated time by the ultrasonic velocity, and the triangle (P) (A) (
The position of the work equipment can be detected from the calculation in B).

In this way, when performing tillage work in the field in work zone (1), the fixed items are fixed as shown in (A) in Figure 2.
, (B) Only two ultrasonic transmitters (3) and (4) are required, and the distance M (a) (b) from the points (A) and (B) to the mobile work vehicle (2) is exceeded. By measuring with sound waves, (
Even if there are some obstacles on the A-P) line or the (B-P) line, the distance can be measured with almost no adverse effect. Therefore, multiple mobile work vehicles (2)...
TI (
This makes it possible to realize a low-cost unmanned driving system.

In addition, a time difference is provided between the transmissions of the ultrasonic transmitters (3) and (4), and the timing of each transmission is adjusted to the distance measuring device 21 (5).
) side, so each transmitter (3)
The signals of (4) and (4) can be identified, and the time interval from the ultrasonic transmission time to the arrival time from the receiver (5A) to each transmitter (3) and (4) can be constant ΔI, and the distance As shown in Figure 2, we can calculate the planned course (po).
Determine the corresponding (X) and distance! By measuring (a) and (b), it is possible to easily check whether the current position of the mobile work vehicle (2) is on the planned course (e) L and correct the position.

In addition, in contrast to the rectangular work area (1), in the irregularly shaped work area (23), the periphery of 1 work area (23),
Ultrasonic transmitters (3) and (4) are installed at one location in a, and the mobile work vehicle (2) is connected to the transmitter (3) and (4) at that location.
Equipped with an ultrasonic distance measuring device (5) that can measure the distance to It is configured to make it possible.

As shown in Fig. 10, ultrasonic transmitters (3) and (4) are arranged on the left and right sides of the center of the irregularly shaped work section (23). The line connecting the is the reference vj (
Set the coordinates of the reference line (A) as the X-axis and the Y axis that passes through the transmitter (3) and is orthogonal to the X-axis, using the transmitter (3) position as the origin, and move the X sleeve. Divide into the working width of the working vehicle (2). The intersection points of the center line (chi) of each working width and the peripheral line (su) are xi, X7, X3, X4. X
5", go around each point position of these x1 to Xi, and then calculate the (+) (-)
The process is started by writing the data on the CPU.

This stored topographical data can be stored and reproduced, and it is also possible to input the data on a desk if a topographical map is available.

The effect of this embodiment is that the control work can be performed in the same pattern as the first embodiment, except that input by data teaching is required for each work section (23) as the first work.
In determining the position of transmitters (3) and (4) (A and B),
It is desirable that the (X) is between (3) and (4), and the turning position of (2) for mobile work is x.
It is sufficient to subtract the Y coordinate values of points 1 to xt by the headland width.

The effect of this embodiment is mobile work! From (2), t
By measuring the distance to the fl sound wave transmitters (3) and (4) using ultrasonic waves, it has good adaptability to waves with large irregularities on the ground surface, and is superior to optical guidance systems. In addition, it is most suitable for mowing lawns, and can also be used for cleaning irregularly shaped areas, cleaning beaches, and cleaning steep slopes such as ski resorts where it is possible to perform mobile work (2). It can also be used for p-insertion work.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, in which Fig. 1 is an overall perspective view, Fig. 2 is a t-plane view showing its operation, Fig. 3 is a partial side view, and Fig. 4 is a part of it. 5 is a side view of the unit, FIG. 6 is a control block diagram, FIG. 7 is a process diagram showing the operation, FIG. 8 is a perspective view of another embodiment, and FIG. 9 is a diagram showing the operation. FIG. Figure 41, code (1) is the work area, (2) is the mobile work vehicle,
(3), (4) are ultrasonic transmitters, (5) are TFLRF
The wave side range device is shown.

Claims (1)

[Claims] A pair of ultrasonic transmitters (3) and (4) are placed at two arbitrary positions sandwiching the work area (1) near the periphery of the work area (1) of the mobile work vehicle (2) at a certain time difference. The mobile work vehicle (2) is equipped with a pair of ultrasonic transmitters (3) and (4) so as to emit signals alternately, and the mobile work vehicle (2) is operated in a direction perpendicular to the line (a) connecting the pair of ultrasonic transmitters (3) and (4). is equipped with an ultrasonic distance measuring device (5) capable of detecting distance by receiving ultrasonic waves, and detects the distance from the ultrasonic transmitters (3) and (4). (5) A guiding device for a mobile work vehicle, characterized in that it detects the movement position (b) of the mobile work vehicle (2) while measuring the distance between these two positions based on the time taken until the mobile work vehicle (2) receives the signal. .