JPS6327203Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a running control device for an unmanned vehicle that controls the running of the vehicle by signals from a guide wire laid on the floor.

Conventionally, driving control in unmanned vehicles has been
As shown in the figure, an alternating current is passed through the induction wire 4 laid on the floor, and the magnetic field generated by the induction wire 4 is detected by two pickup coils 2a and 2b attached to the vehicle body 1, and the induced voltage of these two pickup coils is The steering of the vehicle was controlled based on the difference between the two. Furthermore, in order to run the vehicle stably, it is necessary to install a pick-up coil in front of the fixed wheels 5 in the direction of travel. Therefore, forward pickup coils 2a, 2b and reverse pickup coils 3a, 3b are provided so that these pickup coils can be switched at the same time as the vehicle is switched between forward and backward movement. When such an unmanned vehicle moves forward, the distance Ls between the pick-up coils 2a, 2b and the axle of the fixed wheel 5 is
The larger the value, the more stable the running condition will be. however,
There is a limit to the size of distance Ls due to the structure of the vehicle body.
Therefore, in order to compensate for this drawback, the forward pick-up coils 2a and 2b are each set at a predetermined angle with respect to the center line of the vehicle body to detect the mounting attitude angle. With such a pick-up coil, a detected value can only be obtained as a value of distance from the cable or a mixture of distance and angle (attitude angle) components, and furthermore, the detected value of the pick-up coil, that is, the induced voltage is It is easily affected by fluctuations in the current flowing through the guide wire and induction disturbances, such as changes in magnetic permeability around the cable, making accurate running control difficult.

The present invention was developed with the aim of eliminating the above-mentioned drawbacks of the conventional system, and uses a single sensor to detect the components of the magnetic field generated from the guiding wire in three mutually orthogonal directions, and performs steering control based on each of these detected values. The present invention provides a driving control device for an unmanned vehicle.

Hereinafter, the present invention will be described in detail based on one embodiment of the accompanying drawings.

Figure 3 shows the detector S used in the control device of the present invention.
In the figure showing an example, the detector S includes two coils arranged in parallel with each other in X, Y, and Z axes directions perpendicular to each other, and coils 7 arranged in parallel with each other with their polarities matched in the directions of these axes. ,8,9,10,11,1
2 are combined with each other as shown in the figure, and the outputs of the two coils facing the same axis are added together. This detector S is connected to vehicle A.
Position H on the longitudinal center axis P on the floor of the vehicle body 1
(FIG. 4), the detector S is mounted so that the direction of the central axis P and the Y-axis direction of the detector S coincide with each other.

Now, for example, as shown in FIG.
When the angle between the center of the detector S and the guide line 4 (this is called the attitude angle) is l, and the horizontal distance between the center of the detector S and the guide line 4 (this is called the deviation) is l, the coil 7 of the detector S _X1 , e _X2 in the coil 8, e _Y1 in the coil 9, e _Y2 in the coil 10, e _Z1 in the coil 11, and e _Z2 in the coil 12 are generated. Then, the signal obtained by adding the outputs of the two coils facing the same axis is e _X ,
If e _Y , e _Z , e _X = e _X1 + e _X2 , e _Y = e _Y1 + e _Y2 , e _Z
It is expressed as =e _Z1 +e _Z2 . The attitude angle and the deviation l are expressed as follows using these induced voltages e _X , e _Y , and e _Z .

=a tan ^-1 e _Y / _{e X} ...(a) l=b cos×e _Z /e

As shown in the above formulas (a) and (b), the attitude angle is set by coil 9,
The deviation _{l is calculated based on the ratio between the output e Y of} coils 11 and ₁₂ and the output _e For example, even if the induced magnetic field is disturbed due to fluctuations in the current flowing through the guide wire 4 or due to the influence of magnetic objects existing near the guide wire, the influence of this disturbance of the magnetic field will appear in the calculated values of the attitude angle and the deviation l. do not have.
For example, due to the disturbance of the induced magnetic field mentioned above, the voltage of equation (a)
If e _Y is multiplied by K, the voltage _e The value is also not affected by the disturbance of the magnetic field.

FIG. 6 is a diagram showing an example of a control circuit, in which noise is removed from the output signals e _X , e _Y , and e _Z of the detector S through band pass filters 15, 14, and 13, respectively. _{The signal e}
After being synchronously rectified at , the signal is input to the arithmetic circuit 19 .
Further, the signal e _Z is synchronously rectified by the synchronous rectifier 17 in accordance with the signal e _X , like the signal e _Y , and then input to the arithmetic circuit 20. The arithmetic circuit 19 executes the arithmetic operation of the above formula (A) using the signal e _Y and the signal e _X , and e ₂ ==a tan ^-1
An attitude angle signal e ₂ of e _Y /e _X is calculated and applied to the forward/reverse changeover switch 23 . The arithmetic circuit 20 outputs the signal e _Z and the signal
Execute the calculation of the above formula (b) using e _X , e ₁ = l = b
A deviation signal e ₁ of e _Z /e _X cos is calculated and applied to the side input of the differential amplifier 24. The deviation setting device 21 is used to preset the amount of deviation between the guide wire 4 and the vehicle body 1, and applies a deviation setting signal e ₀ to the side input of the differential amplifier 24. The differential amplifier 24 amplifies the deviation between the signal e ₁ and the deviation set value e ₀ and applies it to the side inputs of the differential amplifiers 25 and 26 as the attitude angle set value.
The forward/reverse discriminator 22 determines whether the vehicle is moving forward or backward, and applies a control signal to the forward/reverse selector switch 23 to switch the forward/reverse selector switch 23 to the contact 23a when the vehicle is moving forward, and to the contact 23b when the vehicle is going backwards. . The forward/reverse selector switch 23 outputs the attitude angle e ₂ to the side input of the differential amplifier 25 when the vehicle moves forward.
When moving backward, the signal is inverted by the sign inverter 27 and then applied to the side input of the differential amplifier 26. The differential amplifier 25 applies a deviation signal e between the attitude angle setting value and the attitude angle to the side input of the differential amplifier 28 during forward movement. Further, the output -e of the differential amplifier 26 is applied to the side input of the differential amplifier 28 when the vehicle is moving backward. The differential amplifier 28 outputs the deviation e between the signal e〓 or -e〓 and the feedback signal e _f and applies it to the steering control device 29 . The steering control device 29 performs steering control of the vehicle A in response to the input signal e, and causes the vehicle A to travel along the guide line 4.

Note that when performing travel control in which the center of the vehicle coincides with the guide line 4, the set deviation amount is zero.

For example, assume that the position of the detector S of the unmanned vehicle A that is moving forward is _l1 away from the guide line 4, as shown in FIG. 7a, and that the attitude angle of the vehicle A is ₁ . Also, when the deviation setting amount is zero,
The deviation signal _e1 directly becomes the original signal for the attitude angle setting value. A deviation signal between this attitude angle setting value and attitude angle ₁ is applied as a steering angle setting value to the side input of the differential amplifier 28, and at the same time, a steering angle signal e _f corresponding to the current steering wheel steering angle θ ₁ is input. It is applied to the side input of differential amplifier 28. Then, the output signal of the differential amplifier 28 controls the snake angle of the steering wheel 6, and both the deviation and the attitude angle change. Then, the deviation signal and attitude angle signal change every moment according to the control, and continue until l==0, that is, until the vehicle A is in the state shown in FIG. 7b.

As explained above, according to the present invention, the X, Y, and Z components of the induced magnetic field can be detected simply and accurately by a single detector. Even if the induced magnetic field is disturbed due to a fluctuation in the current flowing through the induction wire or a magnetic object existing near the induction wire,
Since the attitude angle and deviation of the vehicle can be detected with high accuracy, the vehicle can be properly guided to travel regardless of the disturbance of the induction magnetic field.

[Brief explanation of the drawing]

1 and 2 are diagrams showing a conventional example of an unmanned vehicle, FIG. 3 is a perspective view showing an embodiment of a detector used in the travel control device for an unmanned vehicle according to the present invention, and FIG. 4 is a diagram showing a conventional example of an unmanned vehicle. , A diagram showing an example of installing the sensor shown in FIG. 3 in an unmanned vehicle according to the present invention, FIG. 5 is a diagram explaining the principle of snake steering, and FIG. 6 is an unmanned vehicle according to the present invention. FIG. 7 is a block diagram showing an embodiment of the travel control device according to the present invention, and FIG. 7 is an explanatory diagram of the steering control by the control device according to the present invention. 1...Vehicle body, 5...Fixed wheels, 6...Switching wheels,
7, 8, 9, 10, 11, 12...Coil, 1
3, 14, 15...Band pass filter, 16,
17...Synchronous rectifier, 18...Rectifier, 19,2
0...Arithmetic circuit, 21...Difference setting device, 22...
Forward/forward discriminator, 23... Forward/forward switching switch, 2
4, 25, 26, 28... Differential amplifier, 27...
Sign inverter, 29...Snap steering control device, S...Detector, A...Vehicle.

Claims (1)

[Scope of Claim for Utility Model Registration] In a travel control device that detects a magnetic field generated from a guide wire to control the steering of an unmanned vehicle, the respective axes are in the vehicle width direction X, longitudinal direction Y, and vertical direction of the vehicle. first, second, and third pick-up coils for detecting induced magnetic fields disposed close to each other on the vehicle in a manner facing Z; and the magnetic field detected by the first and second pick-up coils, respectively. a first calculation means for determining the attitude angle of the vehicle with respect to the guide line based on the ratio of the magnitudes of the magnetic fields detected by the first and third pickup coils, respectively; The present invention is characterized by comprising: second calculation means for determining the deviation of the vehicle with respect to the guide line; and means for controlling the steering of the vehicle based on each output of the first and second calculation means. Travel control device for unmanned vehicles.