JPH1056816A - Working vehicle leading controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a working vehicle leading controller that enables stable steering control and stable running of a moving vehicle while maintaining a predetermined running accuracy in a plurality of running routes. SOLUTION: This working vehicle leading controller comprises a leading wire provided for supplying an electric current to the ground side, a steering magnetic-field detector means for detecting strength of the magnetic field generated by the current on the working vehicle V side, a control means 12 for controlling an electric steering motor that leads the running vehicle on the basis of information detected by the steering magnetic-field detector means in a plurality of mutually parallel running routes in the longitudinal direction of the leading wire 2, and a magnetic-field variation detector means GK for detecting variations of the magnetic field strength in the direction along the vehicle body width in such a way that in the working vehicle leading controller which controls the running vehicle, the value of a control variable in operation of the electric motor is obtained from a deviation of the detected value from the preset target value and a steering direction control constant which is obtained based on data detected by the magnetic-field variation detector means GK.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic field detecting means for detecting an intensity of a magnetic field formed by an electric current on a ground side, provided with an induction wire to which an electric current is supplied,
In each of a plurality of traveling paths along the longitudinal direction of the guide line and parallel to each other, based on information detected by the magnetic field detecting means, a steering operation means is provided for guiding a moving vehicle along each of the traveling paths. The present invention relates to a work vehicle guidance control device provided with control means for controlling.

[0002]

2. Description of the Related Art In a work vehicle guidance control device having the above-described structure, the strength of a magnetic field formed by a current supplied to a guidance wire is as follows.
Because it has characteristics determined according to the separation distance from the guide line, based on the detection information of the strength of this magnetic field, in each of a plurality of parallel traveling paths along the longitudinal direction of the guide line,
The work vehicle can be guided.

In the guidance control device having the above configuration, conventionally, for example, the deviation is determined based on the deviation between the detected value of the magnetic field strength detected by the magnetic field detecting means and a preset target value. The steering operation means is controlled so as to be small, and the control constant for the deviation at this time is always set to a constant value.

[0004]

By the way, in the guidance control device having the above structure, the strength of the magnetic field detected by the magnetic field detecting means is inversely proportional to the square of the separation distance from the guide wire. The change in the strength of the magnetic field becomes large with respect to the change in the travel route, and the travel route located at a location close to the guide line and the travel route located far away from the guide line in each travel route The variation width of the strength of the magnetic field on the traveling route is large.

Therefore, when the vehicle travels along each of the traveling routes, even if the actual deviation of the vehicle body from the target traveling position is the same, the deviation between the detection value of the magnetic field detecting means and the target value differs. Value. In other words, a change in the output value of the magnetic field detecting means with respect to a change with respect to the target position of the vehicle body has a different value in each of the traveling paths.

As a result, as described above, in the above-described prior art, since the control constant is constant, the operation amount of the steering operation means is different in each of the traveling routes. In order to improve the accuracy of the steering control in, if a control constant is set so that the steering control can be performed with the set accuracy on a traveling route that is far away from the guidance line, When the vehicle is guided along a traveling route in a location where the vehicle is traveling, the amount of change in the output value of the magnetic field detection means becomes too large, a hunting phenomenon occurs, the steering control becomes unstable, and the traveling state of the work vehicle becomes improper. Problems such as the body becoming unstable and swinging had occurred.

Therefore, when traveling along one of a plurality of traveling routes, the control constant is changed according to the strength (absolute value) of the magnetic field in the traveling route in accordance with the value. A configuration for setting, for example, a configuration in which a control constant is obtained from map data set in advance according to the strength of the magnetic field and set is considered.

However, the above-described improved configuration still has the following disadvantages. That is, even if the strength of the magnetic field formed by the current supplied to the induction wire is the same, the deviation between the detection value of the magnetic field detection means and the target value is
In some cases, the relative relationship with the vehicle displacement to be corrected by the steering control, that is, the deviation from the target position of the vehicle, may not always be constant. For example, the magnitude of the current flowing through the induction wire changes to a different value due to aging,
At the same point due to the difference in the installation state of the return path of the current of the induction wire provided in a loop to supply the current, or the difference in the electrical resistance in the ground if circulating through the ground It is conceivable that the strength of the magnetic field changes. As described above, when the state of formation of the magnetic field due to the current supplied to the induction wire changes due to various factors, even if the strength of the magnetic field detected by the magnetic field detection means is the same, the vehicle body travels. There is a possibility that the amount of change in the strength of the magnetic field when the unit is deviated from the path by a unit amount will be a different value. As a result, even when the strength of the magnetic field is the same and the deviation is the same, the correction amount (steering operation amount) of the vehicle body may be different.

However, in the above-described improved configuration, if the strength of the magnetic field is the same, the control constant for steering control is the same. Therefore, as described above, when the magnetic field formation state changes due to various factors, There is a disadvantage that the steering operation amount becomes a value different from the proper value, and there is a possibility that proper steering control may not be executed.

The present invention has been made in view of such a point, and an object of the present invention is to achieve a stable steering while maintaining a predetermined accuracy in each of a plurality of traveling routes by a rational configuration. An object of the present invention is to provide a work vehicle guidance control device that can perform control and allow a work vehicle to run stably.

[0011]

According to the first aspect of the present invention, a work vehicle traveling on a traveling route along a longitudinal direction of a guide line is provided with a state of change in the strength of the magnetic field along a lateral width of the vehicle body. Is provided, and the control means obtains a control constant for steering control based on the detection information of the magnetic field change detection means. Then, based on the control constant for the steering control, and a deviation between a value detected by the steering magnetic field detecting means and a preset target value,
The steering control is executed by obtaining the operation amount of the steering operation means.

That is, the control constant is a constant that defines the correlation between the amount of deviation of the detected magnetic field strength and the amount of operation of the steering operation means. The degree of change in the strength of the magnetic field along the width direction, that is, the direction substantially orthogonal to the longitudinal direction of the guide line, is actually determined, and the amount of operation is determined in accordance with the degree of change. It is possible to make adjustments so that the relative relationship with the direction operation amount is always kept constant.

As a result, even when the state of formation of the magnetic field formed by the current is changed due to various factors, the steering operation means for the deviation of the strength of the magnetic field caused by the positional deviation of the vehicle body. It is possible to always make the relative relationship of the operation amount appropriate, so that regardless of the traveling route, the operation amount is always the appropriate operation amount regardless of the distance from the guide line. Since the steering operation means is controlled, it is possible to perform stable steering control while maintaining the setting accuracy.

According to the characteristic configuration of the present invention, a predetermined reference control constant is applied to one of the plurality of travel routes as the control constant for the steering control. Is set as a reference traveling route, and the control means:
When traveling along a traveling route other than the reference traveling route, the reference control constant is corrected based on the detection information of the magnetic field change degree detecting means and set as a control constant for the traveling route. ing.

In the reference traveling route, a reference control constant set in advance to an appropriate value is applied as a control constant for steering control. it can. Then, on a traveling route other than the reference traveling route, since the degree of magnetic field change is different from that of the reference traveling route, the reference control constant is corrected based on the detection information of the magnetic field variation detecting means to change the magnetic field on that route. The control constant is set in a state corresponding to the condition. As a result, it is possible to set a control state similar to the control state on the reference traveling route on any traveling route, and it is possible to perform appropriate steering control with less excess and deficiency.

According to a third aspect of the present invention, the control means controls the magnetic field change in the travel route at the start end of the travel route before traveling along a travel route other than the reference travel route. Detection information of condition detection means,
The reference control constant is corrected based on the detection information of the magnetic field change degree detecting means on the reference traveling route, and is set as a control constant for the traveling route.

That is, at the start end of the travel route on which the work vehicle should travel, the actual magnetic field change in the route is detected, and based on the detected information and the information on the magnetic field change in the reference travel route. By correcting the reference control constant, it is possible to more accurately set the steering control state on the traveling path to be substantially the same as the steering control state on the reference traveling path, and to perform appropriate steering on all traveling paths. Control can be performed.

According to a fourth aspect of the present invention, the magnetic field change state detecting means includes a pair of magnetic field detecting sections provided at a predetermined interval along the vehicle width direction. The magnetic field detector is configured to function as a steering magnetic field detector.

Therefore, in order to detect the degree of change in the magnetic field, the operation is performed by effectively utilizing the detection information of one of the pair of magnetic field detectors installed at a set interval along the vehicle width direction. By performing the direction control, the configuration can be simplified by combining the use of the magnetic field change state detecting means and the steering magnetic field detecting means, as compared with a case in which the magnetic field change detecting means and the steering magnetic field detecting means are separately provided.

According to the characteristic configuration of the fifth aspect, each of the magnetic field detecting units constituting the magnetic field change state detecting means includes:
It is installed at an interval corresponding to the interval between adjacent traveling routes. Then, when the work vehicle travels along one of the plurality of travel paths, one of the magnetic field detectors executes the guidance control along the traveling path during travel. Therefore, the strength of the magnetic field for the current travel route is detected, and the other magnetic field detector detects the magnetic field for the current travel route when the work vehicle travels along the next adjacent travel route. Then, the intensity of the magnetic field for the next traveling route, which is detected by the above, is detected.

Therefore, when the vehicle is traveling along one of the plurality of traveling routes, the degree of change in the magnetic field is detected based on the strength of the magnetic field corresponding to the next traveling route. When traveling on the current travel route, it is possible to predict the degree of change in the magnetic field in the next travel route, and to set a control constant in advance using the idle time of control such as during transition from the current travel route to the next travel route. By doing so, it is possible to quickly execute the steering control without waiting for the setting operation of the control constant in the next traveling route.

According to a sixth aspect of the present invention, the work vehicle is provided with a route end detecting unit for detecting that the vehicle is at the end of the traveling route, and the control constant correction unit is provided with a route end detecting unit. Is configured to correct the control constant based on the detection information.

Therefore, the control constant is automatically corrected by detecting that the work vehicle is at the start end of the traveling route, so that the control constant is corrected based on a manual operation. In comparison, there is no disadvantage that the command for the correction operation is mistakenly forgotten, and the control constant can be reliably corrected in advance, and the steering control can be executed in an appropriate state.

According to the seventh aspect of the present invention, when traveling on a certain traveling route, the magnetic field detection for the next traveling route is started when the route end detecting section detects that the traveling route is at the end of the traveling route. The detection information in the section is sequentially stored in the storage means in association with the detection information of the distance detection means for detecting the traveling distance of the work vehicle. Then, when traveling on the next traveling route, the control means executes the steering control using the storage information stored in the storage means as a control target value.

Therefore, not only the steering control constants but also the steering control target values can be set together with appropriate values for each of the traveling routes at all times in accordance with the actual traveling route conditions. Therefore, it is possible to execute the steering control more suitable for the road surface condition.

According to the eighth aspect of the present invention, the output gain of the magnetic field detection unit for the current traveling route is based on the detection information of the magnetic field strength detected by the magnetic field detection unit for the next traveling route. In the traveling route where the target value is set and the strength of the magnetic field is detected by the magnetic field detector for the next traveling route, prior to the guidance traveling along the traveling route, the magnetic field detection for the current traveling route is performed. The output gain in the section is automatically adjusted to the target value. When the output gain is changed and adjusted to the target value, the control constant is corrected to an appropriate state in accordance with the target value.

As a result, even when the range of variation of the magnetic field strength in each traveling route is large, an appropriate output gain target value is always obtained based on the detection information in the magnetic field detection unit for the next traveling route. Automatic adjustment will cause the detection value to be too large and the detection error due to the output distortion of the amplifier to increase, or the detection value to be too small to detect an appropriate deviation and generate a detection error for the vehicle body position shift. When the output gain is adjusted to the target value in this way, by correcting the control constant corresponding to the target value, the detection error is always suppressed to a small value.
A stable steering control state can be maintained.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The work vehicle guidance control device according to the present invention will be described below.

As shown in FIG. 1, a work vehicle guidance control device moves a work vehicle V in a rectangular field 1 as an example of a guidance area by moving a plurality of traveling vehicles V parallel to each other along the longitudinal direction of the field 1. Each of the routes k is configured to be able to guide the vehicle in an unmanned state.

On each side (ridge) in the outer periphery of the field 1,
Each of the guide wires 2 having a length substantially equal to the length of the ridge is installed along the longitudinal direction of the ridge, and each of the guide wires 2 is provided with an AC current having a predetermined frequency by a current supply source as a current supply means. Is supplied. In other words, alternating currents of the frequency fa (Hz) and the frequency fc (Hz) are supplied by the current supply sources 3 to the respective guide lines 2 a and 2 c installed along the ridges on both sides along the long direction of the field 1. The frequency fb (Hz) and the frequency fd are supplied by the current supply sources 3 to the respective guide wires 2b and 2d which are supplied and installed on the ridges on both sides along the short direction.
(Hz) alternating current is supplied. The frequency is
The frequency is set to several hundred Hz to several tens KHz.

As shown in FIG. 2, each of the guide wires 2 is configured such that the current flows through the ground through a plurality of piles 4 made of a conductive material that is driven into the ground. , Even if the leads are installed over long distances,
The configuration is such that the installation can be easily performed only by driving the stake 4 on both sides in the longitudinal direction. In the ground, the driving depth of the pile 4 is set so that the current flows through the lower clay layer G2 having a relatively low electric resistance, instead of the ground layer G1 having a relatively high electric resistance.

When a current flows through the guide wire installed as described above, a magnetic field is formed by the current. The theoretical value of the magnetic field strength with respect to the distance from the guide wire can be obtained by calculation. The strength of the magnetic field is inversely proportional to the square of the distance from the guide wire. Therefore, if the supplied current value is constant, as shown in FIG. 3, the change characteristic of the magnetic field strength with respect to the distance from the induction wire is determined, and the magnetic field at a certain point in the field 1 is determined. Has a substantially constant magnitude.

The work vehicle V is provided with a rotary tillage device 6 as a ground work device at the rear of the four-wheeled traveling vehicle body 5, so that the work on the ground 1 (plow work) can be performed while traveling. It has become. An engine is mounted on the traveling vehicle body 5, and the power of the engine is transmitted to each wheel via a transmission equipped with a forward / reverse switching mechanism 7 capable of turning on and off the power transmission so that the vehicle travels. The power of the engine is transmitted to the rotary tilling device 6. The left and right front wheels are provided so as to be steerable by an electric motor 9 as a steering operation means.

The working vehicle V has a traveling distance sensor 10 as a distance detecting means, for example, a rotary encoder for detecting the traveling distance of the vehicle body by detecting the number of revolutions of the axle, and detects the direction of the vehicle body. An azimuth sensor 11 as azimuth detecting means, a control device 12 using a microcomputer as control means for controlling operations of the forward / reverse switching mechanism 7, the steering electric motor 9, and the like are provided.

At the front of the traveling vehicle body 5, as information on the position (separation distance) of the work vehicle with respect to each of the guide lines, the intensity of a magnetic field formed by an alternating current supplied to each of the guide lines is detected. Three magnetic field sensors are provided side by side along the vehicle body width direction. Of these, the side magnetic field sensors 13R and 13L located on the left and right sides are ridges on both sides along the long direction of the field 1. Guide lines 2a, 2 installed along
c is detected as the strength of the magnetic field formed by the alternating current having the frequency fa and the frequency fc. Is configured to detect the position information from each of the guide wires 2b and 2d installed along the ridges on both sides along the short-length direction as the strength of the magnetic field formed by the alternating current having the frequency fb and the frequency fd. I have.

The control device 12 guides the work vehicle V along each travel route k on each of the plurality of travel routes k based on information detected by the side magnetic field sensors 13R and 13L. Executes the control, and, based on the detection information from the central magnetic field sensor 14 as the path end detection section, detects that the end or start of each travel path k has been reached, and determines that the end has been reached. When it is detected, the vehicle V is configured to execute turning control to cause the work vehicle V to revolve and guide the vehicle to enter an adjacent next travel route.

That is, as shown in FIG. 4, the outputs of the side magnetic field sensors 13R, 13L and the central magnetic field sensor 14 are respectively processed by the signal processing unit 15 and then given to the control unit 12, where Based on the detection information, the steering electric motor 9 is guided so as to be guided along each traveling route k.
At the end of the traveling route k, the magnetic field detection information and the direction sensor 11 and the traveling distance sensor 1
Based on the detection information of 0, the steering electric motor 9, the forward / reverse switching mechanism 7, and the like are controlled so as to make a cornering run.

As shown in FIG. 5, the central magnetic field sensor 14 includes a detection coil 16a in which an induced electromotive force is generated by an alternating magnetic field formed by an alternating current flowing through the induction wire;
An amplifier 16b that amplifies the output of the detection coil 16a to a predetermined level, and a frequency filter that passes only the output of the detection coil 16a corresponding to the frequencies fb and fd of the current flowing through each of the induction wires 2b and 2d. It comprises a band-pass filter BPF, a DC conversion circuit DC for converting its output into a DC signal, and the like.

The side magnetic field sensors 13R and 13L are provided with a vertical detecting coil 17 for detecting a magnetic field component of an alternating magnetic field formed by an alternating current flowing through the induction wires 2a and 2c along the vehicle vertical direction. Width detecting coil 18 for detecting a magnetic field component along the line, and amplifiers 19 and 2 for amplifying the output of each detecting coil to a predetermined level.
0, a band-pass filter BPF as a frequency filter that passes only the output corresponding to the frequencies fa and fc of the currents flowing through the induction wires 2a and 2c among the outputs of the detection coils 17 and 18, and converts the output to a DC signal DC conversion circuit DC, and calculation units 21 and 22 for calculating the strengths of the respective magnetic fields based on the vertical component and the horizontal component corresponding to each of the frequencies fa and fc. I have. As shown in FIG. 12, the calculation units 21 and 22 calculate the strength of the composite magnetic field r based on the triangle theorem based on the vehicle body vertical component p and the lateral width component q. It is configured.

With this configuration, for example, FIG.
As shown in FIG. 2 (a), even when the work vehicle V is running and one of the wheels enters the concave portion and the vehicle body is inclined at an angle θ from the horizontal position, the vehicle is supplied to the guide line. The magnetic field formed by the currents
As shown in FIG.
By calculating the resultant magnetic field by calculation, the strength of the accurate magnetic field, that is, the separation distance from the guide wire can be accurately detected.

As described above, each side magnetic field sensor 13R, 1R
3L, detection information corresponding to each of the frequency fa and the frequency fc is output, and the central magnetic field sensor 14 outputs the detection information corresponding to each of the frequency fb and the frequency fd. However, the signal processing unit 15 selectively outputs the detection information of the higher detection level, that is, the detection information of the work vehicle V closer to the corresponding guide line. The signal processing unit 15
As shown in the figure, each of the magnetic field sensors 13R, 13L, 14
Is output to the control device 12, and the control device 12 determines the output having the higher detection level among the outputs of different frequencies of the magnetic field sensors 13R, 13L, and 14 and selects the output. Analog switches AS _1,
AS _{2 and} AS ₃ are configured to supply a selection signal.

Based on the detection information of the central magnetic field sensor 14, the control device 12 separates the distance from the one of the guide lines 2b and 2d, which are installed on the ridge along the short direction, with the higher detection level. Is calculated, and when the separation distance reaches a set value, it is determined that the work vehicle V has reached the end position of each traveling route k. As shown in FIG. 7, the guide wires 2b and 2d installed on the ridges along the short direction are installed in a state where both end portions are bent in a substantially L shape toward the inside of the field 1. . With this configuration, the intensity of the magnetic field is substantially the same over the entire length of the guide lines 2b and 2d at a point where the separation distance of the guide lines 2b and 2d from the intermediate portion t is the set distance. k
Is set as the end position. This end position is a point located on the inward side of the field 1 by a set distance from the length L of the end bent portion. Incidentally, according to the experiment conducted by the present applicant, if the length H of the bent end portion is, for example, 3 m, the end portion is located at a distance of 5 m from the guide wire.

As described above, the reason why the end position of the traveling route k is set inward of the end of the field 1 is that, as shown in FIG.
In the magnetic field strength distribution at the same distance, the relationship between the magnetic field strength and the distance is not linear near the end of the guide wire, and guidance control based on the magnetic field strength may not be performed well. Because there is.

As shown in FIG. 8, each guide wire 2 has
As a frequency filter which is an example of a current suppressing unit that suppresses a current flowing through another induction wire from flowing through the ground, a band-pass filter 23 that allows passage of only a frequency of a current supplied to the induction wire is provided. Have been. The band-pass filter 23 is configured by a resonance circuit in which a coil 23a and a capacitor 23b are connected in series, and is configured such that its resonance frequency corresponds to the frequency of the current. Therefore, even if a current of a different frequency flows through the ground from another induction wire, the inflow current is suppressed from flowing through the induction wire, and the possibility that each magnetic field sensor detects erroneous information is minimized. I have.

Detection of the side magnetic field sensors 13R and 13L
Each analog switch AS corresponding to output information₁, AS_ThreeOut of
The amplification gain for amplifying the force is
Change and adjust to multiple stages (four stages) based on switching information
It is configured to be. That is, each of the amplification gains
The output of the four different amplifiers 24, 25, 26, 27
For inputting one of the two to the control device 12.
Switch AS_Four, AS _FiveIs selected by the control device 12
It is configured to dictate the content. Supplied to the guide wire
The strength of the magnetic field formed by the current
Changes greatly with changes in the separation distance.
If the amplification gain is kept constant, the
It is difficult to detect with appropriate resolution and detection accuracy is low
To the control device 12
The input level is, for example, as shown in FIG.
The appropriate magnetic field strength when the separation distance changes by a unit distance
So that the change in height is identifiable, in other words
Amplification gain so that it is in the appropriate output range with high resolution
Is automatically adjusted.

The side magnetic field sensors 13R and 13L are
One of the side magnetic field sensors is installed at a set interval in the vehicle body width direction, and when the work vehicle V travels along one of the plurality of travel paths k, the traveling vehicle Magnetic field detection unit G for the current traveling route for detecting the strength of the magnetic field for executing the guidance control along the traveling route k in the middle
Functions as K _1, the other side the magnetic field sensor, to be detected by the magnetic field detector GK ₁ for the current travel route when caused to travel the work vehicle along the next adjacent travel path k Field detection unit GK for the next traveling route for detecting the strength of the magnetic field
It is configured to function as ₂ . In other words, the other side magnetic field sensor sequentially detects the magnetic field of the next traveling route k while traveling on the current traveling route k, and this detection information is the distance information detected by the traveling distance sensor 10. In such a state, the information is sequentially stored in a memory M as a storage means.

In the next traveling path k in which the magnetic field detection information is stored, the controller 12 calculates the magnetic field detection information stored in the memory M and the end position of the traveling path k detected by the traveling distance sensor 10. based of on the travel distance information, it obtains a target value of the strength of the magnetic field at each point on the travel route k, and its target value, the side magnetic field sensor which serves as a magnetic field detector GK ₁ for the current travel route Is configured to execute guided traveling control for driving and controlling the traveling electric motor 9 based on the deviation from the detected value.

The control device 12 also controls the magnetic field detector G for the current traveling route when the vehicle is guided along the next traveling route k based on the magnetic field detection information stored in the memory M.
Sets a target value of the output gain of K _1, prior to the induction travel in the next travel path k, is configured to automatically adjust the output gain to the target value. Specifically, if the maximum value of the magnetic field strength stored in the memory M exceeds the set upper limit value for gain adjustment, an amplifier having a gain one stage lower than the current gain is selected, and If the value is less than the lower limit value for gain adjustment, a selection signal is issued to the analog switches AS ₄ and AS ₅ so that an amplifier having a gain one stage higher than the current gain is selected. Has become. Each analog switch AS ₄ , A
Gain of S ₅ is always to be adjusted to the same value. The set upper limit and the set lower limit for the gain adjustment are
It is set as an upper and lower limit range in which the linearity of the output change as an analog value is guaranteed.

[0049] Also, the control device 12, the magnetic field detector and the detection value of the lateral magnetic field sensor which serves as a GK _1, steering operation amount deviation is multiplied by a control constant between the target value for the current travel route, i.e. , And a target operation amount of the electric motor is obtained. Then, the magnetic field detector GK for the current traveling route
₁ and based on the magnetic field strength of the detection information detected by the magnetic field detector GK ₂ for the next travel route, the time of traveling the following travel route, as the operation amount is a proper range, the control It is configured to correct the constant.

Next, the control operation of the control device 12 will be described. When the work vehicle V is guided in the field 1, the work vehicle V is manually driven on the first travel route k in a state where the work vehicle V is along the appropriate travel route k prior to the automatic guidance control by the control device 12. Let it. At this time, the detection of the traveling magnetic field sensor 10 and the detection information of the side magnetic field sensor (the sensor 13R on the right side in the case of FIG. 1) of the next traveling route along with the start of traveling from the starting end position of the traveling route k. The information is sequentially written and stored in the memory M in a state where the information is associated with the information. Also, among a plurality of data sampled at every set time as the vehicle travels on the first travel route, a plurality (n) of the respective detection values of the left and right side magnetic field sensors 13R and 13L near the center of the travel route. An average value of the difference values of the sampling data α ₁ ... Α _n , β ₁ ... Β _n is obtained, and the steering on the traveling route is determined based on the average value and a constant γ set in advance based on experiments or the like. previously obtained control constants for the control as a reference control constants G _1. Specifically, the calculation is performed based on the following [Equation 1].

[0051]

(Equation 1)

Then, the work vehicle is moved to the starting end of the next traveling route k.
After moving to, automatic guidance control is started.
Prior to that, as shown in FIG.
Magnetic field detector GK₁Side magnetic field sensor that functions as
In the case of 1, the sensor 13L on the left side is initialized.
Together with step 1) before it is applied on that route
The control constant is set (step 2). Of this control constant
To explain the setting, the starting point of the current travel route
Of the left and right side magnetic field sensors 13R and 13L
The difference value Zn of the output value is obtained, and the difference value Zn
Difference value Z in traveling route₁And the reference control constant G
₁Based on the following [Equation 2]
Control constant Gn is calculated. Note that each of the difference values Z
n, Z₁Is set sampling for each driving route
The average value of multiple detection values sampled every time
Is calculated.

[0053]

Gn = (Z ₁ / Zn) · G ₁

The setting of such control constants is executed for each traveling route at the beginning of the traveling route.
In other words, the magnetic field change state detecting means GK is configured to determine the change state of the magnetic field strength along the vehicle body width direction in the path on which the work vehicle travels by using the left and right side magnetic field sensors 13R and 13L. This magnetic field change detection means G
The control device 12 is configured to obtain a control constant for steering control on each traveling route based on the K detection information.

Then, the work vehicle V is driven at the work traveling speed.
Magnetic field detection information stored in the memory M
And travel information based on the detection information of the travel distance sensor 10.
Find the target value of the current magnetic field strength on the path k
And the magnetic field detector GK for the current traveling route₁Side to act as
The deviation between the detection value of the magnetic field sensor 13L and the target value is controlled.
By multiplying by the control constant to obtain the steering operation amount,
Drive control of the steering electric motor 9 (step
3). Therefore, the magnetic field detector GK for the current traveling route ₁But,
This corresponds to the steering magnetic field detecting means. This guided run
When the line control is executed, the magnetic field detection unit G for the next traveling route
K_TwoSide magnetic field sensor on the next traveling route that functions as
In the case of 1, the detection information of the right sensor 13R) is used as the travel distance.
In a state where the memory M
(Step 4).

When it is detected based on the detection information of the central magnetic field sensor 14 that the terminal of the traveling route k has been reached,
The number n of traveling routes is counted up (steps 5 and 6),
If the count value has not reached the set number of routes ns of in the field 1 (step 7), the memory M to write the stored magnetic field strength maximum value Xm of, beyond the gain adjustment setting an upper limit value S _GM The analog switch AS so that an amplifier having a gain one stage lower than the current gain is selected.
₄ , a selection signal is instructed to AS ₅ to change the output gain to the lower side (steps 8 and 9). The maximum value Xm
Is smaller than the set lower limit value _SGL for gain adjustment, a selection signal is instructed to the analog switches AS ₄ and AS ₅ so that an amplifier having a gain one stage higher than the current gain is selected. , The output gain is increased (steps 10 and 11). When the output gain is changed in this way, the control constant is also appropriately corrected in accordance with the change amount (steps 12 and 13).

In this manner, the drive control of the electric motor is always performed with an appropriate control constant in accordance with the detected value of the magnetic field strength and the changing situation of the output gain, so that hunting of the control and occurrence of a detection error occur. As much as possible.

Next, the side magnetic field sensor which serves as a magnetic field detector GK ₁ for the current travel route is switched to that of the opposite side (the right side of the sensor 13R) (step 14). This is because their positional relationship is reversed by a change in the direction of the vehicle body.

Next, a turning control for turning the vehicle in a turning direction so as to be positioned at the start end of the next traveling route k is executed (step 15). As shown in FIG. 13 (a), after the vehicle travels straight ahead while maintaining the steering operation in the neutral state for a set distance from the end position of the traveling route k, the direction sensor 11 is reset, and the direction of the vehicle body is set to 180. The vehicle travels at the maximum turning angle until it is detected that the vehicle has been inverted, and then travels straight until it is detected that the start point of the next travel route k has been reached based on the detection information of the central magnetic field sensor 14. (Step 16).

At the start of the next traveling route,
As shown in FIG. 13B, based on the detection information of the side magnetic field sensor functioning as the magnetic field detector for the current traveling route k and the storage information stored in the memory M, the next traveling route is determined. It is necessary to move the vehicle forward while turning so as to be in line with the vehicle, and to perform the width adjustment. At this time, the magnetic field detection information for the next traveling route is in a bent state. The state is corrected to an appropriate state based on the detection information of the path and the detection information of the degree of change in the magnetic field as described above. After that, the guided traveling control is executed in a state along the traveling route.

After it is detected based on the detection information of the central magnetic field sensor 14 that the head of the next traveling route k has been reached, the detection value of the magnetic field detecting unit GK ₁ for the current traveling route and the target When the set time elapses after the deviation from the value (stored information) falls within the set range and the value is stabilized, the above-described setting of the control constant is executed. That is, the left and right side portions field sensor 13R in the current travel route, the difference value Zn of the detected value of each of 13L, based on the difference value Z ₁ and the reference control constants G ₁ in the first traveling path, above [equation 2 ], The control constant Gn in this traveling route
Is calculated. Note that the difference value Zn in the current traveling route
Is calculated based on the detection information on the start end side.

Thereafter, the above-described guided traveling control is executed. At this time, if the gain has been changed in steps 9 and 11, the amount of change in the detection information stored in the memory M is also changed. Is multiplied by a gain corresponding to the target value. Then, steps 2 to 15 are repeated to guide the work vehicle V sequentially along each traveling route k, and when the number reaches the set number of routes ns, the control ends (step 7).

In the current traveling route k, the strength of the magnetic field stored when traveling on the preceding traveling route k and the current traveling route k
Is controlled to be the same as the detected magnetic field at
Since the installation intervals of the side magnetic field sensors 13R and 13L are set to be narrower than the working width of the rotary tilling device 6 with respect to the ground, the working area of the rotary tilling device 6 wraps on each traveling path k. That is, no unworked area is generated. Also, each side magnetic field sensor 13
The installation intervals of R and 13L can be changed and adjusted freely.

[Another Embodiment] (1) In the above embodiment, the magnetic field change state detecting means is provided with a pair of magnetic field detecting sections provided at a set interval along the vehicle width direction. The magnetic field detecting section functions as the steering magnetic field detecting means, and the other magnetic field detecting section detects the magnetic field detecting section for the current traveling path when the work vehicle travels along the next adjacent traveling path. Although the configuration is such that the strength of the magnetic field for the next traveling route to be detected by the above is detected, the following configuration may be used instead of such a configuration.

In the above-described embodiment, the degree of change in the magnetic field may be detected by using the detection value of the other magnetic field detection unit and the detection value of the central magnetic field sensor. A magnetic field sensor provided separately at a distance may detect the degree of magnetic field change.

Further, a magnetic field sensor capable of detecting the strength of the magnetic field is provided on the working vehicle so as to be movable for a set distance along the lateral direction of the vehicle body. , The strength of the magnetic field may be sequentially detected, and the degree of change in the magnetic field may be detected. The magnetic field sensor may function as a steering magnetic field detection unit, or may be provided separately from the steering magnetic field detection unit.

(2) In the above embodiment, the control constant is obtained by correcting the reference control constant at the start end of each traveling route for which the control constant is to be obtained. You may do so.

When the vehicle is traveling on the previous route in the traveling route for which the control constant is to be determined, the magnetic field in the next traveling route is determined based on the information on the difference between the side magnetic field sensors 13R and 13L at that time. The degree of change may be predicted and set, or after such prediction and setting, the information of the difference value of the side magnetic field sensors 13R and 13L at that time during the traveling of the next traveling route. , The control constant may be corrected again.

(3) In the above embodiment, the reference traveling route is determined, and the correction to the reference control constant at that time is executed for each route. However, instead of such a configuration, for example, Appropriate control constants corresponding to the degree of change detected by the degree of change detection means are stored in advance as map data, and the control constants are determined directly on the basis of the detection information of the degree of change detection in each traveling route. It may be.

(4) In the above embodiment, a central magnetic field sensor is provided as a route end detecting unit to detect that the vehicle has reached the end of the traveling route, and to correct the control constant in accordance with the detection. However, instead of such a configuration, the operator may appropriately instruct the correction operation by manual operation.

(5) In the above-described embodiment, the end of the traveling route is detected by the central magnetic field sensor as the route end detecting unit. A laser beam may be irradiated in the lateral direction, and the end of the route may be detected by a sensor that detects the laser beam. The present invention may be implemented in various configurations such as a configuration instructing the side.

(6) In the above embodiment, the output gain of the steering magnetic field detecting means is automatically adjusted. However, the automatic gain may not be adjusted.

(7) In the above embodiment, the case where the guide lines are provided on both the left and right sides of the guidance target area has been described. However, the guide lines may be provided on only one side. May be guided sequentially from a traveling route closer to the guide line to a route farther away, or may be sequentially guided from a traveling route farther from the guide line to a route closer to the guide line.

(8) In the above embodiment, the working vehicle is a four-wheel type and the left and right front wheels are provided so as to be able to swing freely. However, all four wheels are provided so as to be able to swing freely, and the front and rear wheels are mutually connected. A configuration in which the vehicle turns with a small turning radius that rocks in different directions, or a configuration in which the front and rear wheels rock in the same direction and the work vehicle moves in parallel in an oblique direction may be adopted. Further, a configuration in which a pair of left and right crawler traveling devices are provided and a steering operation configuration for applying braking to one side may be employed.

(9) In the above embodiment, the working vehicle is provided with the rotary tilling device. However, the working vehicle may be provided with a seedling transplanting device, a chemical spraying device, or the like. It may be a mobile vehicle such as a transport vehicle that does not include the vehicle.

[Brief description of the drawings]

FIG. 1 is a plan view showing a guidance state.

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

FIG. 3 is a diagram showing a magnetic field intensity distribution.

FIG. 4 is a control block diagram.

FIG. 5 is a configuration diagram of a magnetic field detection unit.

FIG. 6 is a configuration diagram of a signal processing unit.

FIG. 7 is a plan view showing an installation state of a guide wire.

FIG. 8 is an electric circuit diagram of an induction wire.

FIG. 9 is a diagram showing output characteristics when the output gain is switched.

FIG. 10 is a flowchart of a control operation.

FIG. 11 is a plan view of a working vehicle.

FIG. 12 is a diagram showing a magnetic field detection state.

FIG. 13 is a diagram showing a turning control state.

[Description of Signs] 2 Guide wire 9 Steering operation means 10 Distance detecting means 12 Control means 13R, 13L Magnetic field detecting section 14 Path end detecting section GK Magnetic field change degree detecting means GK ₁ Steering magnetic field detecting means M Storage means V Work vehicle

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Katsuya Aburada, Inventor: 1-40-2 Nisshin-cho, Omiya-shi, Saitama Prefecture Within the Research Institute for Biological Sciences (72) Masada Suzuki, 1-chome, Nisshin-cho, Omiya-shi, Saitama No. 40 No. 2 Within the Organization for Promoting Specified Industrial Technology for Biological Sciences (72) Inventor Yoji Yamanaka 64 Ishizukitamachi, Sakai City, Osaka Prefecture Inside Kubota Sakai Plant (72) Inventor Hosei Fujii 64 Ishizukitamachi, Sakai City, Osaka Prefecture Inside Kubota Sakai Works (72) Inventor Yasuo Irie 64 Ishizukita-cho, Sakai City, Osaka Prefecture Inside Kubota Sakai Works (72) 64 Yukio Yokoyama, 64 Ishizukita-machi Sakai City, Osaka Kubota Sakai Manufacturing Co., Ltd. Inside

Claims (8)

[Claims] An induction wire to which a current is supplied is installed on the ground side, and a steering magnetic field detecting means for detecting a strength of a magnetic field formed by the current is provided on a work vehicle side; In each of the plurality of traveling paths along the longitudinal direction and parallel to each other, the steering operation means is controlled to guide the work vehicle along each of the traveling paths based on information detected by the steering magnetic field detecting means. Control means for performing the steering based on a deviation between a value detected by the steering magnetic field detection means and a preset target value, and a control constant for steering control. A work vehicle guidance control device configured to obtain an operation amount of an operation means, wherein the work vehicle is provided with magnetic field change state detection means for obtaining a change degree of the magnetic field strength along a vehicle body width direction. And the control means is Wherein the magnetic field changes on the basis of the detection information of the degree detecting means, the guidance and control apparatus for working vehicle that is configured to determine the control constants for the steering control. 2. One of the plurality of traveling routes is set as a reference traveling route to which a preset reference control constant is applied, as the steering control control constant. When traveling along a traveling route other than the reference traveling route, based on the detection information of the magnetic field change detection means,
The work vehicle guidance control device according to claim 1, wherein the reference control constant is corrected and set as a control constant for the traveling route. 3. The control means, prior to traveling along a travel route other than the reference travel route, at a start end of the travel route, detection information of the magnetic field change state detection means in the travel route, 3. The work vehicle guidance control device according to claim 2, wherein the reference control constant is corrected based on information detected by the magnetic field change state detection means on the reference travel route. 4. The magnetic field change state detecting means includes a pair of magnetic field detecting units installed at a predetermined interval along a vehicle width direction, and one magnetic field detecting unit detects the steering magnetic field. The work vehicle guidance control device according to any one of claims 1 to 3, wherein the guidance control device is configured to function as a means. 5. Each of the magnetic field detection units is provided in a state where the magnetic field detection units are installed at intervals so as to correspond to an interval between adjacent traveling routes, and one of the magnetic field detection units includes the plurality of magnetic field detection units. When the vehicle travels along one of the traveling routes, the control unit detects the strength of the magnetic field for the current traveling route to execute the guidance control along the traveling route during traveling. The strength of the magnetic field for the next traveling route that is detected by the magnetic field detecting unit for the current traveling route when the magnetic field detecting unit of the present invention travels the work vehicle along the next adjacent traveling route. 5. The work vehicle guidance control device according to claim 4, wherein the control device is configured to detect 6. The work vehicle is provided with a route end detection unit that detects that the traveling vehicle is at an end of the travel route, and the control unit is configured to control the traveling vehicle to detect a travel route by the route end detection unit. The work vehicle guidance control device according to any one of claims 3 to 5, wherein the control constant is corrected in accordance with detection of being located at a start end. 7. A distance detecting means for detecting a traveling distance of the work vehicle, and a magnetic field detecting unit for the next traveling route from when the end of the traveling route is detected by the route end detecting unit. A storage unit for sequentially storing the detection information in association with the detection information of the distance detection unit; and the control unit executes the steering control using the storage information stored in the storage unit as the target value. 7. The guidance control device for a work vehicle according to claim 6, wherein the guidance control device is configured to: 8. A target value of an output gain in the magnetic field detection unit for the current traveling route, based on detection information of a magnetic field strength detected by the magnetic field detection unit for the next traveling route. In the traveling route in which the magnetic field intensity is detected by the magnetic field detecting unit for the next traveling route, prior to the guidance traveling along the traveling route, the current traveling route Is configured to automatically adjust the output gain of the magnetic field detection unit to the target value, and when the output gain is adjusted to the target value, corrects the control constant to an appropriate state in accordance with the target value. The work vehicle guidance control device according to any one of claims 5 to 7, wherein the work vehicle guidance control device is configured to: