JPH0850510A - Guide controller for moving vehicle - Google Patents

Abstract

PURPOSE:To provide a guide controller for moving vehicle with which a guidable range can be extended while satisfactorily executing the guide control of a moving vehicle. CONSTITUTION:On the ground side, a guide line forming a magnetic field is installed and on the moving vehicle side, a controller 13 for controlling a steering cylinder and detecting sensors 11R and 11L for detecting the distance from the guide line as the intensity of the magnetic field are provided. At respective plural traveling courses of which the distances from the guide line are mutually different, the steering cylinder is controlled so that the moving vehicle can be traveled along the lengthwise direction of the guide line, and an amplifier circuit 17 for amplifying the outputs of the detecting sensors 11R and 11L and inputting them to the controller 13 automatically adjusts an amplification gain so that the output values to the controller 13 can be set within a proper set range in respective states positioned at the respective traveling courses.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has an induction wire for supplying a current to form a magnetic field on the ground side and a moving vehicle side,
Steering operation means for changing the direction of the vehicle body, control means for controlling the steering operation means, and magnetic field strength detection means for detecting the distance from the guide wire as the magnetic field strength are provided. Means, based on the detection result of the magnetic field strength detection means, so that the moving vehicle travels in a direction along the longitudinal direction of the guide wire in each of a plurality of travel routes having different distances from the guide wire. And a guidance control device for a moving vehicle configured to control the steering operation means.

[0002]

2. Description of the Related Art Conventionally, the guidance control device for a moving vehicle has been constructed such that the output of the magnetic field strength detecting means is amplified by an amplifying means having a constant amplification gain and input to the control means.

[0003]

By the way, the strength of the magnetic field formed by the guide wire decreases in inverse proportion to the square of the separation distance as the separation distance from the guide wire increases, and the variation range thereof. However, the conventional configuration has the following disadvantages.

That is, in the above-mentioned conventional structure, since the detected value of the magnetic field strength detecting means is amplified by a constant amplification gain, the output value after the amplification, that is, the input value to the control means is The fluctuation range may exceed the proper setting range of the input value to the control means.

As a result, in the area outside the proper setting range, the distance information from the guide line to the moving vehicle cannot be accurately determined, and the steering control means is arranged so that the moving vehicle travels along the traveling route. Since there is a possibility that the control operation for controlling the vehicle cannot be executed well, the range in which the traveling route can be set is limited to a narrow range, and the number of the traveling routes is increased so that the range in which the moving vehicle can be guided is as wide as possible. There was a disadvantage that I could not do.

According to the present invention, although the above-mentioned inconveniences are solved and the control operation for controlling the steering control means so that the moving vehicle travels along the travel route can be satisfactorily executed, It is an object of the present invention to provide a guidance control device for a mobile vehicle, which can increase the number of traveling routes to make the range in which the mobile vehicle can be guided as wide as possible.

[0007]

The features of the first invention are as follows:
A guide wire for supplying a current to form a magnetic field is installed on the ground side, and a steering operation means for changing the direction of the vehicle body, a control means for controlling the steering operation means, and the guide on the moving vehicle side. Magnetic field strength detection means for detecting the distance from the line as the strength of the magnetic field is provided, the control means, in each of a plurality of travel routes different distance from the guide wire, the moving vehicle is the In the guidance control device for a moving vehicle, which is configured to control the steering operation means based on the detection result of the magnetic field strength detection means so as to travel in the direction along the longitudinal direction of the guidance line, Output amplification means for amplifying the output of the detection means and inputting to the control means is provided, and the output amplification means outputs the output value to the control means in each state in which the moving vehicle is located on each traveling route. Is appropriate To be in a constant range, the amplification gain in that it is configured to automatically adjust.

A characteristic structure of the second invention is to specify a structure suitable for carrying out the first invention, wherein the output amplifying means outputs to the control means on the basis of the output of the magnetic field strength detecting means. The point is that the amplification gain is automatically adjusted so that the output value falls within the appropriate setting range.

A characteristic configuration of the third invention is to specify a configuration suitable for carrying out the first or second invention, wherein the output amplifying means includes a plurality of amplifiers having different amplification gains, and the magnetic field. It is composed of an amplifier selecting means for selecting one of the plurality of amplifiers having an appropriate amplification gain based on the output of the intensity detecting means.

[0010]

According to the characteristic construction of the first invention, since the strength of the magnetic field formed by the current supplied to the guide wire and the distance from the guide wire have a uniquely defined relationship, The distance from the moving vehicle is detected by the magnetic field strength detection means as the strength of the magnetic field, and based on the detection result, the control means performs the steering operation so that the moving vehicle runs in the direction along the longitudinal direction of the guide line. The means are controlled.

The output value of the magnetic field strength detecting means is amplified by the output amplifying means and input to the control means, but the output value of the magnetic field strength detecting means is changed as the distance from the guide wire of the moving vehicle changes. Even when the output voltage of the moving vehicle changes significantly, the amplification gain of the output of the output amplifying means is automatically adjusted so as to be within a proper setting range for the control means in each state where the moving vehicle is located on each traveling route. Of.

Therefore, even if the detection value of the magnetic field strength detecting means fluctuates greatly, the amplification gain is automatically adjusted as described above, so that proper steering control can be executed, and it is set as the traveling route. The region that can be formed can be set over a wide range from a place near the guide wire to a place far away.

According to the characterizing structure of the second invention, there is the following function in addition to the function of the characterizing structure of the first invention. Based on the output value of the magnetic field strength detection means, the amplification gain of the output amplification means is automatically adjusted so that the input value to the control means falls within the set proper range. As compared with a configuration or the like in which the amplification gain is preset to be switched and adjusted, the amplification gain can always be adjusted with high accuracy.

According to the characterizing feature of the third invention, there are the following effects in addition to the effects of the characterizing feature of the first or second invention.
Based on the output value of the magnetic field strength detection means, an amplifier having an appropriate amplification gain is selected from a plurality of amplifiers so that the input value to the control means falls within the setting proper range, and the amplifier selects the magnetic field strength detection means. The output value of is amplified and input to the control means.

As described above, by switching and using a plurality of amplifiers having different amplification gains, the error in the fluctuation of the output with respect to the fluctuation of the input is smaller than that in the structure in which the amplification gain of one amplifier is changed. .

[0016]

According to the characterizing feature of the first invention, although the control for allowing the moving vehicle to travel along each of the plurality of travel routes can be favorably executed, the number of travel routes is increased. As a result, it has become possible to maximize the range in which the mobile vehicle can be guided.

According to the characterizing structure of the second invention, the following effects are obtained in addition to the effects of the characterizing structure of the first invention. The output value of the magnetic field strength detection means is always amplified with an appropriate amplification gain.

According to the characterizing feature of the third invention, the following effect is obtained in addition to the effect of the characterizing feature of the first or second invention.
In the output amplifying means, there is little error in output fluctuation with respect to input fluctuation, and automatic steering control along the travel route based on the detection information of the magnetic field strength detecting means can be performed accurately.

[0019]

Embodiments will be described below with reference to the drawings. FIG.
As shown in Fig. 5, an AC current is supplied to the ridges 2a, 2b, 2c, 2d located on the four sides of the rectangular field 1 to form a magnetic field by supplying the induction wire 3 installed over substantially the entire length of each ridge. An induction traveling control system that automatically controls traveling of a moving vehicle V such as an agricultural tractor along a plurality of traveling routes in a field by an electromagnetic induction method is configured.

As shown in FIG. 2, one end of each of the guide wires 3 is connected to the metal pile body 4 driven into the ground G in a conductive state, and the other end thereof is a support formed of an insulator. Part 5
And is erected and supported by the metal pile body 4 and the support portion 5. Further, another metal pile body 6 driven into the ground G is provided on the other end side of the induction wire 3, and a pair of connections in the current supply device 7 as a current source provided corresponding to each induction wire 3. One connection terminal 8 of the terminals is connected to the other end of the guide wire 3, and the other connection terminal 9 is connected to the other metal pile body 6. As described above, the current supplied from the current supply device 7 flows through the induction wire 3 and the underground G.

The current supply device 7 is configured to supply an alternating current having a current value of about 1 ampere to several amperes to the induction wire 3 at a frequency of about several hundred hertz to 10 kilohertz, and is installed in each ridge. The current supply device 7 is adapted to supply currents of different frequencies. The frequency of the current supplied to the guide wire 3 along the ridge 2a on one side in the longitudinal direction and the frequency of the current supplied to the guide wire 3 along the ridge 2c on the other side in the longitudinal direction are different from each other. It is set.

By supplying the current to the guide wire 3 in this way, a magnetic field is formed outside the guide wire 3, and the strength of the magnetic field is a distance from the guide wire 3 as shown in FIG. The larger L becomes, the smaller the distance L becomes in inverse proportion to the square of the distance L. However, at the points where the distance L is equal, that is, at the respective points in the direction along the guide wire 3, the magnetic field strengths become substantially equal.

The moving vehicle V is provided so that it can be driven by an engine, and the direction of the steered wheels 10 can be changed by a steering cylinder CY as steering control means. Then, as shown in FIG. 4, as described above, the magnetic field strength that changes according to the distance L from the guide wire 3 is
A pair of left and right coil-type detection sensors 11R and 11L as magnetic field strength detection means for detecting the distance information is installed on both the left and right sides of the moving vehicle V at set intervals, and the detection information of each of the detection sensors 11R and 11L is set. Based on the above, a control device 13 as a control means for controlling the electromagnetic control valve 12 for the steering cylinder CY is provided. The control device 13 includes a microcomputer. The detection signals of the detection sensors 11R and 11L are configured to be converted into a DC signal by the signal processing unit 14, amplified, and then input to the control device 13. Although not described in detail, each of the detection sensors 11R and 11L is provided with two pairs of detection characteristics suitable for the magnetic fields of the induction wires 3 having different frequencies. Detection sensor 11
Whether to use R or 11L can be appropriately switched.

The configuration of the signal processing section 14 will be described. Coil-type detection sensors 11R, 11 by the magnetic field
An induced electromotive force due to electromagnetic induction is generated in L, but as shown in FIG. 5, the signal is subjected to detection processing by the detection circuit 15 and converted into a DC component of an effective value by the DC conversion circuit 16. Then, the DC signal is amplified by an amplification circuit 17 as an output amplification means by an appropriate amplification gain, and input to the control device 13.

The amplifier circuit 17 includes four amplifiers 18a, 18b, 18c and 18d each having a different amplification gain.
And an analog switch 19 as an amplifier selection unit that selects one of the plurality of amplifiers that has an appropriate amplification gain based on the outputs of the detection sensors 11R and 11L. As shown in FIG. 3, the detection values of the detection sensors 11R and 11L have a large fluctuation range with respect to the change of the separation distance L. Further, when the separation distance L becomes large, the fluctuation of the detection value with respect to the change of the distance becomes small. If the entire variation range is processed with a constant amplification gain, the distance cannot be detected accurately when the separation distance L becomes large. Therefore, the amplification gain is automatically adjusted according to the detection values of the detection sensors 11R and 11L, and the input value to the control device 13 is within the appropriate setting range in each state where the moving vehicle V is located on each traveling route. To adjust. That is, as the detection values of the detection sensors 11R and 11L become smaller, the amplifier having a larger amplification gain is switched to ensure sufficient resolution for the variation of the separation distance L.

Specifically, each amplifier 18a, 18b, 1
All outputs of 8c and 18d are input to the controller 13,
The amplifier within the proper setting range is the analog switch 19
And is input to the control input terminal. FIG. 6 shows changes in the input value to the control device 13, that is, the output value of the amplifier circuit 17, when the amplifier is switched. In the figure, points a, b and c indicate switching points of the amplifier. In FIG. 6, the amplifier is switched to a larger amplification gain toward the right side (the larger the separation distance L). In this way, the input value to the control device 13 is in the proper setting range while being located on each traveling route.

Next, the control operation of the controller 13 will be described. After the moving vehicle V is moved to the start end of the traveling route k by radio control or manual control, steering control is executed so that the vehicle V automatically travels straight along the guide line 3 along the longitudinal direction of the ridge. As shown in FIG.
Of the detection sensors 11R, 1 while being moved to the start end of the
The separation distance L from one guide wire 3 is calculated based on the average value information of the detected values of 1L and the theoretical formula (step 1). Then, as shown in FIG. 8, by the separation distance L and the installation distance d between the detection sensors 11R and 11L,
The equidistant line (the assembly line at the same magnetic field strength point) with respect to the guide wire 3 corresponding to the positions of the left and right detection sensors 11R and 11L in the state (reference state) in which the moving vehicle V is in the normal traveling posture along the traveling route k Convert to information (step 2).
That is, the distance information for each equidistant line from the guide line 3 is obtained, and the difference value ΔH of the magnetic field strength on each of the equidistant lines X1 and X2, that is, the normal traveling posture of the moving vehicle V along the traveling route k. The control target value in the state of is calculated (step 3).

Then, the traveling of the moving vehicle V is started by radio control or manual control (step 4), and when the magnetic field generated by the guide wire 3 installed on the short ridge exceeds the set value, the moving vehicle V travels. Until the end of the path k is detected, the difference between the detected values of the left and right detection sensors 11R and 11L is detected, and the deviation between the detected difference and the control target value is set. When the amount is exceeded, depending on whether the detection value of each of the detection sensors 11R and 11L is larger or smaller than the value (magnetic field strength on each equidistant line) in the reference state used as the control target value, Moving car V
Is deviated to the left or right with respect to the travel route k, and the steering cylinder is operated and controlled to return to the proper travel route k (steps 5 to 10). In this way, the moving vehicle V can be controlled so as to travel straight along the traveling route k.

When it is detected that the moving vehicle V reaches the end of the traveling route k, turning control is executed (step 1).
1). The turning traveling is configured such that the turning control is executed in a predetermined steering operation state in order to travel toward the starting end portion of the next traveling route k.

Further, in the vicinity of the center of the field, the magnetic field generated by the guide wires 3 along the opposing longitudinal ridges is mixed, but the detection sensors having different detection characteristics are appropriately switched to each other by the guide wires on the side closer to each other. The control is executed based on the magnetic field.

[Other Embodiments] (1) In the above embodiment, four amplifiers having different amplification gains are used, but the number of amplifiers is not limited to four, and two amplifiers are used.
Any configuration may be used as long as it selects more than one amplifier. (2) Although a plurality of amplifiers having different amplification gains are used in the above embodiment, the amplifier circuit (output amplifying means) may be configured as follows. As shown in FIG. 9, a fixed gain amplifier 20 having a predetermined amplification gain and a variable gain amplifier 21 capable of variably adjusting the amplification gain are provided, and based on a change in the output of the fixed gain amplifier 20, the variable gain amplifier 20. The gain adjuster 22 may be configured to change and control the amplification gain so that the output of 21 is within the appropriate setting range. (3) Further, the amplification circuit (output amplification means) may be configured as follows. As shown in FIG. 10, the detection sensors 11R and 11L are provided in front of the variable gain amplifier 21.
The logarithmic converter 23 may perform logarithmic conversion of the output value of 1 to linearly approximate the degree of variation of the detected value to simplify the arithmetic processing in the control device 13. According to this structure, the arithmetic processing can be performed in a short time, and the control can be speeded up. (4) The moving vehicle V may be provided with a pair of left and right crawler traveling devices instead of the wheel type traveling mode. In this case, the steering operation means is a power to the left and right crawler traveling devices. Steering control is performed by separately controlling the clutch mechanism that intermittently transmits the transmission, the brake mechanism that is separately provided, and the like.

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

[Brief description of drawings]

FIG. 1 is a plan view showing a guidance control system.

FIG. 2 is a side view showing the installation state of the guide wire.

FIG. 3 is a diagram showing changes in magnetic intensity.

FIG. 4 is a control block diagram.

FIG. 5 is a block diagram of a signal processing unit.

FIG. 6 is a diagram showing changes in the output value of the amplifier circuit.

FIG. 7 is a control flowchart.

FIG. 8 is an operation explanatory diagram in a reference state.

FIG. 9 is a block diagram of an amplifier circuit according to another embodiment.

FIG. 10 is a block diagram of an amplifier circuit according to another embodiment.

[Explanation of symbols]

 3 Guide wire 11R, 11L Magnetic field strength detection means 13 Control means 17 Output amplification means 18a, 18b, 18c, 18d Amplifier 19 Amplifier selection means CY Steering operation means V Mobile vehicle

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Yukio Yokoyama 64 Ishizukita-machi, Sakai City, Osaka Prefecture Kubota Sakai Factory

Claims (3)

[Claims] 1. A guide wire (3) for supplying a current to form a magnetic field is installed on the ground side, and a steering operation means (CY) for changing the direction of the vehicle body is installed on the moving vehicle (V) side. , A control means (13) for controlling the steering operation means (CY), and magnetic field strength detection means (11R), (11L) for detecting the distance from the guide wire (3) as the strength of the magnetic field. The control means (13) controls the direction in which the moving vehicle (V) extends along the longitudinal direction of the guide wire (3) in each of a plurality of travel routes having different distances from the guide wire (3). A guidance control device for a moving vehicle configured to control the steering operation means (CY) based on the detection results of the magnetic field strength detection means (11R) and (11L) so that the vehicle travels to the , The output of the magnetic field strength detection means (11R), (11L) An output amplifying means (17) for widening and inputting to the control means (13) is provided, and the output amplifying means (17) is provided in each state in which the moving vehicle (V) is located on each traveling route. A guidance control device for a moving vehicle configured to automatically adjust an amplification gain so that an output value to the control means (13) falls within an appropriate set range. 2. The output amplifying means (17) adjusts an output value to the control means (13) within an appropriate setting range based on the outputs of the magnetic field strength detecting means (11R), (11L). The induction control device for a mobile vehicle according to claim 1, wherein the amplification control device is configured to automatically adjust the amplification gain. 3. The output amplification means (17) comprises a plurality of amplifiers (18) having different amplification gains.
a), (18b), (18c), (18d) and the plurality of amplifiers (18a), (18b), based on the outputs of the magnetic field strength detection means (11R), (11L).
3. The induction control device for a moving vehicle according to claim 2, further comprising an amplifier selecting means (19) for selecting one of (18c) and (18d) that has an appropriate amplification gain.