JPH1185271A - Guidance control unit for moving vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the precision of guidance control by finding the relative position reflation between a guide line and a vehicle body travel surface for an expected path from magnetic field detection information on the travel distance of a moving vehicle from a path start end position and correcting a target value with the relation. SOLUTION: Guide lines 2 are installed on the sides of the outer peripheral part of a field 1; and current supply sources 3 supplies AC currents of frequencies fa and fc to guide lines 2a and 2c and a current supply source 3 supplies an AC current of frequency fb to the guide line 2b. When the moving vehicle V travels along one of expected travel paths, the target value is set in advance and stored in a storage means. A target value correcting means finds the relative position relation between the guide lines and the vehicle travel surface fo the expected paths according to detection information of a magnetic detecting means corresponding to the travel distance of the moving vehicle V from the start end position of the travel path. Then the target value is corrected according to the relative position relation. A steering control means performs guidance control so that a detected value of the magnetic field detecting means reaches the corrected target value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steering operation means for changing the direction of a vehicle body on a moving vehicle side, in which a guide wire for supplying a current and forming a magnetic field is installed on the ground side. Steering control means for controlling the direction operation means, and a magnetic field detection means for detecting the distance from the guidance line as the strength of the magnetic field,
Distance detection means for detecting a traveling distance of the moving vehicle, wherein the steering control means travels along each of the plurality of scheduled traveling routes at different distances from the guidance line. Accordingly, the present invention relates to a mobile vehicle guidance control device configured to execute guidance control for controlling the steering operation means so that the detection value of the magnetic field detection means becomes a target value.

[0002]

2. Description of the Related Art Conventionally, in the above-described guidance control apparatus for a mobile vehicle, a target value when executing guidance control is configured to use a preset value as it is. Incidentally, as the target value, a configuration in which a theoretical value corresponding to the separation distance from the guide line is used for each scheduled traveling route, for example,
As shown in Japanese Patent Application No. 8-17402 by the present applicant, in a configuration in which the guidance control in the next traveling route is performed based on the detected value while sequentially detecting the magnetic field strength of the next traveling route, In order to correct the error of the detection value at the end of the route caused by the bending when entering the path during turning, the correction is used based on the information on the detection value at the end of the opposite route and used as the target value. There was a configuration to do.

[0003]

By the way, in the guidance control device having the above configuration, a guidance wire installed on the ground side is provided with:
The traveling surface of the mobile vehicle corresponding to the planned traveling route is not always located on the same plane with high accuracy, and the traveling surface may be inclined with respect to the installation state of the guide line. . For example, there is a case in which the route is inclined such that the route start end side is located relatively below the guide line and the route end side is located relatively upward with respect to the guide line. But,
While each scheduled traveling route is set based on the traveling surface of the moving vehicle, in the guidance control based on the target value as described above, the three-dimensional separation distance between the guidance line and the magnetic field detecting means is different. It will be controlled to reach the target value,
Due to the relative position change between the guide line and the traveling surface of the mobile vehicle as described above (relative inclination in the vertical direction, etc.), despite the execution of the guidance control based on the target value, the movement An error may occur between the actual traveling route of the car and the planned traveling route, and proper guidance control may not be performed (for example, see magnetic field data in FIG. 1).

Accordingly, the present invention has been made in view of such a point, and an object of the present invention is to use the detection information of the magnetic field detecting means to determine the relative positional relationship between the guide line and the traveling surface of the vehicle. It is an object of the present invention to provide a guidance control device for a mobile vehicle, which can correct a target value to improve the accuracy of guidance control.

[0005]

According to the present invention, when traveling along one of a plurality of planned traveling routes, the target value is set in advance and stored in the storage means. When the moving vehicle travels along one of the plurality of planned traveling routes, the target value correction unit detects the magnetic field detection unit corresponding to the traveling distance of the traveling vehicle from the route start position. Based on the information, the relative positional relationship between the guide line and the vehicle body running surface corresponding to the planned traveling route is obtained, and the target value is corrected based on the relative positional relationship. Then, the steering control means executes the guidance control so that the detection value of the magnetic field detection means becomes the target value corrected by the target value correction means.

The magnetic field detecting means detects the three-dimensional distance from the guide line as the strength of the magnetic field.
For example, if the strength of the magnetic field is divided into a plurality of magnetic field components such as a vertical component and a horizontal component and detected separately, guidance control is performed so that the combined magnetic field becomes a target value. Is performed, and the relative positional relationship can be obtained from the change in the ratio of those magnetic field components (vertical direction and horizontal direction) corresponding to the traveling distance. Alternatively, a plurality of magnetic field detection units may be provided at intervals in the horizontal direction, and the relative positional relationship may be obtained by a change in the detection value of each of the magnetic field detection units with respect to a change in the traveling distance.

Therefore, based on the relative positional relationship, the target value can be corrected to an appropriate value in accordance with the actual situation of the guide line and the running surface, and the guidance control is performed in an appropriate state with few errors. It becomes possible.

According to the second aspect of the present invention, when the moving vehicle travels along one of a plurality of traveling routes parallel to each other along the longitudinal direction of the guide line, the next traveling route is provided. 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 mobile vehicle travels along the next adjacent traveling route by the magnetic field detecting unit for the next traveling route. Is detected, and the detected value is sequentially stored in the storage unit as a target value in association with the traveling distance information detected by the distance detection unit. When the mobile vehicle travels along the next adjacent traveling route, basically, the target value, which is the last measured value stored in the storage unit, and the magnetic field detection unit for the current traveling route. Guidance control is performed based on the strength of the magnetic field detected by
When the moving vehicle reaches the end of the route, the steering operation means is controlled so as to make a turn toward the starting end of the next adjacent traveling route. That is, the steering control is performed so that the vehicle turns from the end of the route and enters the next route.

In the guidance traveling along the next adjacent traveling route, the traveling route on the opposite side of the information stored in the storage means is maintained until the vehicle travels a set distance from the end of the traveling start route. The mobile vehicle is guided to travel based on the stored information corresponding to the end and the detection information of the magnetic field detection unit for the current traveling route. This is because, as described above, the vehicle enters at the beginning of the route while turning, so that the turning traveling may be continued beyond the route start position until the traveling posture along the appropriate traveling route is attained. In such a state, the target value detected by the magnetic field detecting means for the next path is different from an appropriate value. Therefore, at a location corresponding to such a target value, for example, using detection information near the end of the first travel route (for each travel route each time the vehicle is separated from the guide line, a proportional calculation or the like is appropriately performed). While making corrections), proper guidance control can be performed.

[0010] The target value correcting means is a target value of the guidance control during traveling the set distance from the position of the end of the path on the traveling start side. By correcting the stored information corresponding to the end based on the relative positional relationship as described above,
Correct the error due to the relative positional relationship between the guide line and the traveling surface of the mobile vehicle, make the target value on the route end side appropriate,
Guidance control with high accuracy can be performed.

[0011] According to the characteristic configuration of the third aspect, the target value correcting means may be configured such that the moving vehicle is selected from a plurality of planned traveling routes.
It is configured to obtain a relative positional relationship between the guide line and the traveling surface of the moving vehicle on each of the planned traveling routes, based on detection information of the magnetic field detecting means when traveling along the planned traveling route closest to the guiding line. .

Since the strength of the magnetic field formed by the current is inversely proportional to the square of the distance from the guide wire, the change in the magnetic field with respect to the change in the distance increases as the distance increases.
As a result, the change in the detection result of the magnetic field detecting means with respect to the change in the relative positional relationship between the guide line and the traveling surface of the mobile vehicle as described above appears most prominently at a point closest to the guide line,
The relative positional relationship can be obtained as accurately as possible based on the detection information of the magnetic field detecting means when traveling along the planned traveling route closest to the guide line.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a guidance control device for a mobile vehicle according to the present invention will be described. The guidance control device for mobile vehicles
As shown in FIG. 1, in a rectangular field 1 as an example of a guidance area, a work vehicle V as an example of a moving vehicle is moved along each of a plurality of traveling paths k parallel to each other along the longitudinal direction of the field 1. It is configured so that the vehicle can be guided and guided in an unmanned state.

A guide wire 2 is provided on each side (ridge) in the outer peripheral portion of the field 1, and an AC current of a predetermined frequency is supplied to each of the guide wires 2 by a current supply source. 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 guide wire 2b which is supplied and installed in a circling state along the outer periphery of the field 1 has a frequency fb
(Hz) alternating current is supplied. The frequency is set to several hundred Hz to several tens KHz.

[0015] Each of the guiding line 2a, 2c includes a forward portion 2 _OL thereof, the current supplied from the current source 3 and a return portion 2 _FL for forming a closed loop flowing, suitably in a plan view It is installed on the ground side at a distance. Specifically, as shown in FIG. 3, the forward portion 2 _OL is positioned along the one widthwise side of ridge AZ in the field, the return portion 2 _FL along the widthwise direction other side of the ridge AZ There in a state of being placed on the ground the ground surface in a state that position and, the backward part 2 _FL, are installed to be parallel or substantially parallel to said forward portion 2 _OL. That is, ridge A
It is installed in a loop by effectively utilizing the boundary between Z and the field scene.

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 2 can be calculated. The strength of the magnetic field is inversely proportional to the square of the distance from the guide wire 2. Then, the reversed direction to each other and the forward part 2 the current flowing through the current and the return portion 2 _FL flowing through the _OL, the magnetic field to be formed acts as cancel each other in the opposite direction, the appropriate distance from one another in a plan view Since it is set apart, the change characteristic of the magnetic field strength with respect to the separation distance from the guide wire 2 is determined, and the magnetic field strength at a certain point in the field 1 becomes almost constant. . FIG. 4 shows actual measurement data by the present applicant.

As shown in FIG. 11, the work vehicle V is provided with a rotary tillage device 6 as a ground work device at a rear portion of a four-wheeled traveling vehicle body 5, and a ground work (plow work) of the field 1 while traveling. ) Is configured as an agricultural work vehicle. 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.

The working vehicle V has a traveling distance sensor 10 as a distance detecting means comprising a rotary encoder or the like, which detects the traveling distance of the vehicle body by detecting the number of revolutions of a drive shaft in a transmission mechanism to wheels. A directional sensor 11 as directional detecting means for detecting the azimuth of the vehicle body, a control device 12 using a microcomputer for controlling the operation 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, the strength of a magnetic field formed by an alternating current supplied to each of the guide lines is detected as information on the position (separation distance) of the work vehicle with respect to each of the guide lines. Four magnetic field sensors are provided on both sides of the vehicle body width direction. Of these, one of the left and right guidance magnetic field sensors 13R and 13L is provided on both sides of the field 1 along the longitudinal direction. Each guide line 2 installed along
The position information (separation distance information) from a and 2c is
a and a magnetic field formed by an alternating current having a frequency fc, and the other end left and right magnetic field sensors 14R and 14L are installed in a circumferential state on the outer peripheral portion of the field 1. It is configured to detect position information from the induction wire 2b as the strength of a magnetic field formed by an alternating current having a frequency fb.

The control device 12 moves the work vehicle V along each traveling path k on each of the plurality of traveling paths k based on the detection information from the guidance magnetic field sensors 13R and 13L as the magnetic field detecting means GK. And the end magnetic field sensor 14R, 1
Based on the detection information by the 4L, it is detected that the traveling route k has reached the end or the starting end, and when it is detected that the traveling route k has been reached, the work vehicle V is turned and the next traveling route adjacent to the traveling vehicle k is detected. It is configured to execute turning control for guiding the vehicle to enter. Then, after the guided traveling on each traveling route k is completed, the vehicle travels around the inner portion close to the ridge of the field and travels around the end of each traveling route to plow the roughened area by the turning traveling. Control is executed.

That is, as shown in FIG. 5, each of the guiding magnetic field sensors 13R and 13L, and the end magnetic field sensors 14R and 14R.
The output of L is given to the control device 12 after being processed by the signal processing unit 15, respectively, and based on the magnetic field detection information, the steering electric motor is driven so as to be guided along each traveling path k. 9 at the end of the traveling route k, based on the magnetic field detection information and the detection information of the direction sensor 11 and the traveling distance sensor 10, the steering electric motor 9 and the forward / reverse switching mechanism 7 for turning and traveling. And so on.

The end magnetic field sensors 14R and 14L are
As shown in FIG. 6, each of them has the same configuration, and as shown in FIG. 6, 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 2b, and an output of the detection coil 16a is amplified to a predetermined level. Amplifier 16b
And each of the induction wires 2b,
A band-pass filter BPF as a frequency filter for passing only an output corresponding to the frequency fb of the current flowing through 2d, and a DC conversion circuit D for converting the output to a DC signal
C and the like.

The guiding magnetic field sensors 13R and 13L are
A vertical direction detecting coil 17 for detecting a magnetic field component of the alternating magnetic field formed by the alternating current flowing through the induction wires 2a and 2c along the vehicle body vertical direction, a lateral direction detecting coil 18 for detecting a magnetic field component along the vehicle body lateral direction, Amplifiers 19 and 2 that amplify the output of each of these detection coils 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 such a 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 of the induction magnetic field sensors 13R,
13L is configured to output detection information corresponding to each of the frequency fa and the frequency fc. In the signal processing unit 15, the one having a higher detection level, that is, the work vehicle V The detection information closer to the corresponding guide line is selectively output. As shown in FIG. 7, the signal processing unit 15 includes the magnetic field sensors 13R,
13L is input to the control device 12, and the control device 12
Of the magnetic field sensors 13R and 13L determine the output of the higher detection level from the outputs of different frequencies, and select the analog switches AS _{1 and} AS ₂ so as to select the output.
Is provided to the selection signal.

The controller 12 detects the level of the guidance line 2b installed on the ridge along the short direction based on the detection information of the end magnetic field sensors 14R and 14L during the guided traveling on each traveling path k. , The distance from the guide line is calculated, and when the distance reaches a set value, it is determined that the work vehicle V has reached the end position of each of the traveling paths k.

Further, as shown in FIG.
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.

The signal processing unit 15 controls the output of the intensity of the magnetic field, which is detected by the magnetic field detecting means GK and is input to the control device 12, to an appropriate level for the control operation of the control device 12. A gain adjusting unit TU for adjusting the output gain of the magnetic field detecting unit GK is provided. More specifically, each of the guiding magnetic field sensors 13R, 1R
Each analog switch AS ₁ , A corresponding to 3L detection information
Amplification gain for amplifying the output of the S _2, the controller 1
It is configured to change and adjust in a plurality of steps (four steps) based on the switching information from step 2. That is, the control device 1 is connected to the analog switches AS ₃ and AS ₄ for inputting any one of the outputs of the four amplifiers 24, 25, 26 and 27 having different amplification gains to the control device 12.
2 is configured to instruct selection contents. As described above, the strength of the magnetic field formed by the current supplied to the induction wire greatly changes with the change in the separation distance, and when the amplification gain is kept constant, the strength is appropriate over the entire range. It is difficult to perform detection with a high resolution, and the detection accuracy may be reduced.
As shown in FIG. 9, for example, as shown in FIG. 9, an appropriate change in the strength of the magnetic field can be identified when the distance from the guide wire changes by a unit distance. That is, the amplification gain is automatically adjusted so as to have an appropriate output range.

Each of the above-mentioned induction magnetic field sensors 13R, 13L
Are installed at a set interval in the vehicle width direction,
One of the guiding magnetic field sensors is a work vehicle V,
When traveling along one of the plurality of traveling paths k, the magnetic field detection for the current traveling path for detecting the strength of the magnetic field to execute the guidance control along the traveling path k during traveling. parts function as GK _1, that other guidance magnetic field sensor, is 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 detecting the intensity of the magnetic field to be configured to function as a magnetic field detector GK ₂ for the next travel route.
That is, the other guiding 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.

Similarly, the end magnetic field sensors 14R and 14L are also installed at a set interval in the vehicle body width direction, and one of the end magnetic field sensors is set to the working vehicle V.
When the vehicle travels along one of the plurality of travel paths k, the end for the current path for detecting the strength of the magnetic field in order to execute the end position detection on the travel path k during the travel The other end magnetic field sensor functions as a detection unit, and the other end magnetic field sensor detects in advance the strength of the magnetic field to be detected by the current path end detection unit in the next adjacent traveling route k. Is configured to function as an end detection unit.

In the next traveling path k in which the magnetic field detection information is stored, the control device 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. travel distance based on the information, obtains a target value of the strength of the magnetic field at each point on the travel route k, and its target value, the guidance 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 detection unit 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 below the lower limit for gain adjustment, a selection signal is issued to the analog switches AS ₃ and AS ₄ so that an amplifier having a gain one stage higher than the current gain is selected. Has become. Each analog switch AS ₃ , A
Gain of S ₄ 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.

The control device 12 multiplies a deviation between the target magnetic field sensor, which functions as the magnetic field detector GK ₁ for the current travel route, and the target value by a control constant, and calculates a steering operation amount, that is, , The target operation amount of the electric motor 9 is determined. Then, the magnetic field detector G for the current traveling route
K ₁ and based on the magnetic field strength of the detection information detected by the magnetic field detector GK ₂ for the next travel path, as in when traveling the next travel path, the operation amount is within a proper range, the control constant Is corrected.

Further, in the guided traveling on each traveling route, when the detected value of the magnetic field sensor for the end functioning as the end detecting unit for the current route becomes a preset value, the control device 12 sets the traveling route. It is configured to determine that it is located at the end of the vehicle. Also, with the guidance traveling, the detection value of the magnetic field sensor for the end on the next route side is associated with the detection value of the traveling distance sensor 10. It is designed to remember.

Next, the control operation of the control device 12 will be described. When the work vehicle V is guided and driven in the field 1, the work vehicle V is driven by manual operation in the first travel path k in a state where the work vehicle V is along the appropriate travel path prior to the automatic guidance control by the control device 12. . then,
As the traveling is started from the starting end position of the traveling route k, the detection information of the guiding magnetic field sensor (the right sensor 13R in the case of FIG. 1) of the next traveling route and the end of the next traveling route are used. Each of the detection information of the magnetic field sensor (the right sensor 14R in the case of FIG. 1) is sequentially written and stored in the memory M in a state corresponding to the detection information of the traveling distance sensor 10. In the traveling by manual operation, traveling starts with the rear end of the rotary tilling device 6 located at one end of the field, and stops traveling when the front end of the aircraft reaches the other end of the field. In this way, the first run is performed without any hassle. 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 detection values of the left and right guidance magnetic field sensors 13R and 13L near the center of the travel route. The average value of the difference values of the sampling data α ₁ ... Α _n , β ₁ ... Β _n is obtained, and the steering in 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].

[0036]

(Equation 1)

Then, after moving the work vehicle to the start end of the next traveling route k, the guided traveling control is started.
As shown in 0, prior to, firstly, the current traveling magnetic field detector end magnetic field sensor which serves as an end detection section for the guidance magnetic field sensor and the current path acts as a GK ₁ for route (Fig. 1 In this case, the left side is initialized (step 1). At this time, the control constant applied to the travel route is also set. To explain the setting of the control constant, a difference value Zn between the detection values of the left and right guidance magnetic field sensors 13R and 13L at the starting end of the current traveling route is obtained. Based on the difference value Z _{1 and the} reference control constant G ₁ , a control constant Gn in this traveling route is calculated based on the following [Equation 2]. The difference values Zn, Z
Numeral ₁ is calculated as an average value of a plurality of detection values sampled at each set sampling time in each travel route.

[0038]

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.

When starting the guided traveling control, the turning position of the vehicle body and the rotary tilling are considered in consideration of the longitudinal length of the work vehicle V and the required distance from the turning traveling to entering the traveling route in a predetermined posture. The elevating operation position (appropriate position in the direction along the traveling route) of the device 6 is set in advance as distance information from the control start position.

As shown in FIG. 13, while the work vehicle V is traveling at the traveling speed for work, based on the magnetic field detection information stored in the memory M and the detection information of the traveling distance sensor 10, The target value of the magnetic field strength at the present time on the traveling route k is obtained, and the magnetic field detecting unit GK ₁ for the current traveling route is obtained.
The guided traveling control is executed based on the detection value of the guidance magnetic field sensor 13L functioning as the target value and the target value (step 3). In other words, the deviation between the detected value and the target value is multiplied by the control constant to determine the steering operation amount, and the steering operation amount is calculated as
The driving of the steering electric motor 9 is controlled. When the guided travel control is performed, and the detection information of the guidance magnetic field sensor following the travel path side that functions as the magnetic field detecting unit GK ₂ for the next running path, the magnetic field sensor end of the next traveling path side detection The information is sequentially written and stored in the memory M in a state where each of the information is associated with the detection information of the traveling distance sensor 10 (step 3).

As shown in FIG. 14, the detected value of the magnetic field sensor for the end as the end detecting unit for the current route is such that the rear end of the rotary tilling device 6 matches the stored value corresponding to the elevation position. Is detected, the rotary tilling device 6 is moved up and down (steps 4 and 5). In other words, the tilling work is started and the guided traveling control is continued on the route start side, and the cultivation work is stopped on the route end side, and the vehicle further travels and matches the stored value corresponding to the preset turning position. Then, it is determined that the work vehicle V is located at the end of the traveling route (step 6).

When reaching the end of the traveling route k, the number of traveling routes n is counted up (step 7). If the count value does not reach the set number of routes ns in the field 1 (step 8), the memory is used. strength maximum value Xm of the magnetic field which is written and stored in the M is, if beyond the gain adjustment set upper limit value S _GM, analog switches aS as amplifier 1 step lower gain than the current gain is selected ₃ , a selection signal is commanded to AS ₄ to change the output gain to a lower side (steps 9 and 10). If the maximum value Xm is less than the gain adjustment set lower limit value _SGL , a selection signal is sent to the analog switches AS ₃ and AS ₄ so that an amplifier having a gain one stage higher than the current gain is selected. And the output gain is changed to a higher side (step 11,
12). When the output gain is changed in this way, the control constant is also appropriately corrected according to the change amount (steps 13 and 14).

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

Next, the guidance 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 15). 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 starting end of the next traveling route k is executed (step 16). In this turning control, the azimuth sensor 11 is reset and the vehicle is turned at the maximum turning angle until it is detected that the azimuth of the vehicle body has been reversed by 180 degrees, and thereafter, the detection information of the end magnetic field sensors 14R and 14L is used. When it is detected that the vehicle has reached the start end of the next traveling route k, the turning control is stopped (step 16).

At the starting point of the next traveling route,
As shown in FIG. 14, detection information of a guidance magnetic field sensor functioning as a magnetic field detection unit for the current traveling route and the memory M
Is performed based on the stored information stored in the vehicle, and the vehicle body is turned so as to be in a state along the next traveling route and is moved forward while being narrowed. Then, the detection value of the end magnetic field sensor functioning as the end detection unit for the current route is
When it is detected that the rear end side of the rotary tilling device 6 matches the stored value corresponding to the elevating operation position, the rotary tilling device 6 is lowered to start the tilling operation.

In this way, the guided traveling is started, and the set time elapses after the deviation between the detected value of the magnetic field detector GK ₁ for the current traveling route and the target value (stored information) falls within the set range. When it is stabilized, the control constants are set as described above. That is, the difference value Z between the detection values of the left and right guidance magnetic field sensors 13R and 13L in the current traveling route.
Based on n and the difference value Z ₁ in the first travel route and the reference control constant G ₁ , a control constant Gn in this travel route is calculated based on the above [Equation 2]. The difference value Zn in the current traveling route is calculated based on the detection information on the starting 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.

In the travel route after the second step,
As described above, since the path is bent when entering the path, the information detected by the next path magnetic field detection unit at the path start end and stored in the memory M is information corresponding to the bent path. Therefore, if the guidance control is performed on the next traveling route based on the stored information, the work vehicle will bend similarly, so that the work vehicle will bend in such a region (the vehicle is set to the position corresponding to the elevation operation position by the set distance). In the area before the vehicle travels), it is possible to travel in a straight-line state as much as possible by using the stored information on the end side (see da in FIG. 14) of the stored information on the route of the second stroke. I have to.

That is, at the beginning of the route of the first stroke guided on the basis of the initial data in FIG. 14, proper straight running is performed, and the magnetic field for the next traveling route is at the end of the second stroke. magnetic field information detected by the detector GK ₂ (da see FIG. 14) will detect the value of the proper path. Therefore, using this detection information as reference information, the stored information (control target) near the end of the path having an error due to bending as described above is corrected. Note that, as the work process progresses, the separation distance from the guide line sequentially changes. Therefore, instead of applying the magnetic field information (da) in the second process as it is, the separation distance changes (stroke process). Is changed every time), the ratio is corrected to an appropriate value in consideration of the ratio of the difference Zn between the detection values of the left and right guidance magnetic field sensors 13R and 13L in the reference process and the relevant process. I have to.

Further, in such a process of replacing the target value, the control device 12 stores the target value of the guidance control in the memory M, which becomes the target value of the guidance control during the traveling of the set distance from the end of the route on the traveling start side. The stored information is corrected based on the relative positional relationship between the guide line 2 and the field scene 1 (work vehicle running surface). Therefore, the control device 12
, The steering control means 100 for controlling the steering electric motor 9 and the target value correcting means 101 are constituted.

The correction of the target value based on the relative positional relationship will be described. In this type of guidance control device, the guidance line 2
And the field scene 1 may not always be installed accurately on the same plane. Even if the guide line 2 and each traveling route k are set to be parallel in plan view, for example, FIG.
As shown in FIG. 5, the field scene 1
May be relatively inclined along the vertical direction. However, while each traveling path k is set to have a set interval based on the field scene 1, the strength of the magnetic field formed by the current supplied to the induction line 2 Since this corresponds to a three-dimensional separation distance (see FIG. 16), there is a possibility that an error occurs in the planar view between the one end and the other end of the traveling route even if the strength of the magnetic field is the same. There is.

Therefore, based on the detection information of the magnetic field when the vehicle travels along the travel route closest to the guide line 2 where the change in the relative position is most likely to be affected among the plurality of travel routes as described above, The relative positional relationship between the guide line 2 and the field scene (moving vehicle running surface) in each running route k is determined. In other words, as shown in FIG. 16, when the vehicle travels by the first manual operation, the vehicle travels with high accuracy substantially in parallel with the guide line 2, so that either the left or right guidance magnetic field sensor and the guide line 2 (the forward path and the return path) The distance L in a plan view from the theoretical guiding line by synthesis is constant, and the distance h in the vertical direction at the start and end of the route due to the inclination of the field.
₁ and h ₂ will be different. Therefore, the detection value H ₁ at the beginning of the path of the magnetic field sensor and the detection value H at the end of the path
₂ and the theoretical magnetic field strength (see Equations 3 and 4 below) according to the Biot-Savart equation, the ratio of the distance in the vertical direction is calculated as a relative positional relationship (Equation 5).
Based on the ratio, the stored information corresponding to the opposite path end is corrected and used as a new target value. In this way, guided traveling can be performed with an error caused by a change in the relative positional relationship as small as possible.

[0055]

H ₁ = α · I / 4πx ₁

[0056]

H ₂ = α · I / 4πx ₂ where α is a constant, I is the current value flowing through the induction wire, x ₁ , x
₂ is a three-dimensional separation distance.

[0057]

[Number 5] _{^{x 1 2 = L 2 + h}} 1 2

[0058]

X ₂ ² = L ² + h ₂ ²

In each of the subsequent traveling routes, the above-described process of replacing the target value is performed near the end of the route. However, as described above, the reference stroke (second stroke) is performed. And the ratio of the difference Zn between the detection values of the left and right guidance magnetic field sensors 13R and 13L, respectively, and the guidance line 2 and the field scene 1
(Working vehicle running surface) based on each of the relative positional relationship,
The stored information is corrected and used as a control target.

Then, steps 2 to 17 are repeated,
The work vehicle V is sequentially guided along each traveling route k, and when the set number of routes ns is reached, the guidance control for following the traveling route is terminated, and the process then shifts to circling control (steps 8 and 18). .

A description will be given of the orbital control. The orbital travel as shown in FIG. 2 is performed so that the detection value of the left or right end magnetic field sensor is maintained at a preset target value, and When the azimuth change of about 90 degrees at the corner is detected five times on the basis of the detection information, the transition is made from the first round running to the second round running. At this time, the change from the target value in the first lap to the target value in the second lap is made to change gently so as to suppress the roughening of the field due to a sharp turn.

In this manner, the tilling work is appropriately performed also in the area that is the unworked area in the guided traveling on each of the travel paths k, the good work is performed over the entire field, and the unworked area does not occur. It has become. The installation intervals of the magnetic field sensors 13R and 13L for guidance and the installation intervals of the magnetic sensors 14R and 14L for end portions are configured to be changeable and adjustable.

[Another Embodiment] (1) In the above embodiment, the strength of the magnetic field of the next scheduled traveling route is detected in advance, and is set as the target value for the next traveling route. Instead of the configuration, a control target value for each traveling route is measured in advance, or a target value based on a theoretical value is obtained by calculation, and stored in the storage unit in this manner, and stored in advance. The guidance control may be performed based on the set target value and the detection information of the magnetic field detection unit. In this case, the target value stored in advance may be appropriately corrected based on the relative positional relationship as described above.

(2) In the above-described embodiment, the relative positional relationship is obtained in the first travel route. Instead of such a configuration, the relative positional relationship is calculated every time the vehicle travels along each travel route. May be obtained, and the target value may be corrected each time, or the target value may be corrected using an average value of a plurality of measurement results of the relative positional relationship.

(3) In the above embodiment, when determining the relative positional relationship between the guide wire and the vehicle body running surface, the relative value between the detected value of the magnetic field sensor and the theoretical magnetic field strength according to the Biot-Savart equation is used. Although the positional relationship is obtained by calculation, the present invention is not limited to such a configuration.
At each of the start end and the end of the stroke, a difference value between the detection values of the left and right guidance magnetic field sensors 13R and 13L is determined, and the relative positional relationship is determined based on the ratio of these difference values at both ends. A configuration that is obtained for convenience may be used. Alternatively, guidance magnetic field sensors 13R, 13L on both the left and right sides
Of each sensor and the theoretical magnetic field strength according to the Biot-Savart equation, the actual distance between each sensor and the guide wire (a virtual guide wire in the case of a loop) is calculated. Based on the distance information and the known distance information between the two sensors, three-dimensional position information (height information h1, h2, etc. in FIG. 16) is obtained based on a triangular shape formed by the left and right sensors and the guide lines. It may be obtained by calculation.

(4) In the above embodiment, the guide wire is provided in the form of a loop. However, a single wire is used to ground both ends to the ground, and the current is returned using the ground. What constitutes a route may be used.

(5) As in the above-described embodiment, the configuration in which the magnetic field detection information is used for each of the guidance traveling control of the moving vehicle along each planned traveling route and the control for detecting the end of each planned traveling route. Alternatively, as a configuration of edge detection, for example,
A laser beam may be irradiated laterally at the end of the route, and the end of the route may be detected by a sensor that detects the laser beam. For example, a configuration to instruct the mobile vehicle that the end has been reached,
You may implement with various structures.

(6) In the above-described embodiment, the case where the guidance lines for guidance traveling are provided on both the left and right sides of the guidance target area is exemplified. However, the configuration may be such that the guidance lines are provided on only one side. In the control, the vehicle may be guided to a route that is farther away from the guide line, and may be sequentially guided to a route that is closer to the far side.

(7) In the above embodiment, the vehicle is a four-wheel vehicle and the left and right front wheels are provided so as to be steerable and swingable. However, all four wheels are provided so as to be steerable and swingable. It is possible to adopt a configuration that makes a turn with a small turning radius that swings in different directions from each other, and a running configuration in which the front and rear wheels swing in the same direction and the moving vehicle moves in parallel in an oblique direction. There may be. 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.

(8) In the above embodiment, the rotary tilling device is used as the moving vehicle. However, the moving 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 plan view showing a guidance state;

FIG. 3 is a diagram showing an installation state of a guide wire;

FIG. 4 is a diagram showing a magnetic field intensity distribution.

FIG. 5 is a control block diagram.

FIG. 6 is a configuration diagram of a magnetic field detection unit.

FIG. 7 is a configuration diagram of a signal processing unit.

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 moving vehicle.

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

FIG. 13 is a plan view showing a guidance control state.

FIG. 14 is a plan view showing a guidance control state.

FIG. 15 is a diagram showing a relative position change between a guide line and a field.

FIG. 16 is a diagram showing a change in the position of the magnetic field detection sensor when the relative position changes.

[Explanation of symbols]

 2 Guidance line 9 Steering operation means 10 Distance detecting means 100 Steering control means 101 Target value correcting means GK Magnetic field detecting means GK1 Magnetic field detecting section for current running path GK Magnetic field detecting section for secondary running path M Storage means V Mobile vehicle

Continued on the front page (72) Inventor, Yuki Yamanaka 64, Ishizukita-cho, Sakai City, Osaka, Japan Inside the Kubota Sakai Works, Ltd.

Claims (3)

[Claims] 1. A guide wire for supplying a current and forming a magnetic field is installed on the ground side, and a steering operation means for changing a direction of a vehicle body is provided on a moving vehicle side, and the steering operation means is controlled. Steering control means, magnetic field detecting means for detecting the distance between the guide line and the magnetic field strength, and distance detecting means for detecting the traveling distance of the mobile vehicle, the steering control means, In each of the plurality of scheduled travel routes having different distances from the guide line, to travel along each scheduled travel route,
A guidance control device for a mobile vehicle configured to execute guidance control for controlling the steering operation means so that a detection value of the magnetic field detection means becomes a target value, wherein the plurality of scheduled traveling routes When traveling along one of the plurality of scheduled traveling routes, the target value is set in advance and stored in storage means, and the traveling vehicle travels along one of the plurality of scheduled traveling routes. Based on the detection information of the magnetic field detecting means corresponding to the traveling distance of the moving vehicle from the route start position, obtaining a relative positional relationship between the guide line and the vehicle body traveling surface corresponding to the planned traveling route, A target value correction unit that corrects the target value based on the relationship, wherein the steering control unit causes the detection value of the magnetic field detection unit to be the target value corrected by the target value correction unit. Executing the guidance control Guidance control apparatus for a mobile vehicle that is configured to. 2. The strength of a magnetic field formed by the current when the magnetic field detecting means travels along one of a plurality of traveling paths parallel to each other along the longitudinal direction of the guide wire. And a next traveling to be detected by the magnetic field detecting unit for the current traveling route when the mobile vehicle travels along the next adjacent traveling route. A magnetic field detection unit for the next traveling route that detects the strength of the magnetic field for the route, wherein the steering control unit detects a value detected by the magnetic field detection unit for the next traveling route, the distance detection unit In association with the travel distance information detected by
The target value is sequentially stored in the storage means, and when the mobile vehicle travels along the next adjacent traveling route, the travel value is stored in the storage means until the vehicle travels a set distance from a route end position on the traveling start side. Based on the stored information corresponding to the end of the route on the opposite side of the stored stored information and the detection information of the magnetic field detection unit for the current traveling route, the mobile vehicle is guided to travel, and the set distance is set. After traveling, the mobile vehicle is guided to travel based on the storage information corresponding to the current position of the mobile vehicle among the storage information stored in the storage means and the detection information of the magnetic field detection unit for the current travel route. Further, when the moving vehicle reaches the end portion of each of the traveling routes, the steering device controls the steering operation means capable of changing the traveling direction of the vehicle body so as to make a turn toward the starting end of the next adjacent traveling route. Is configured as the above The target value correction unit is configured to be the target value of the guidance control during traveling a set distance from the route end position on the traveling start side, and the path information on the opposite side of the storage information stored in the storage unit is used as the target value. The guidance control device for a mobile vehicle according to claim 1, wherein the storage information corresponding to the unit is configured to be corrected based on the relative positional relationship. 3. The target value correction unit according to claim 3, wherein the moving vehicle travels along a planned traveling route closest to the guide line among the plurality of planned traveling routes. 3. The guidance control device for a mobile vehicle according to claim 1, wherein a relative positional relationship between the guidance line and the travel surface of the mobile vehicle on each travel route is determined based on the guidance line.