KR0160302B1 - Control system for unmanned carrier vehicle - Google Patents

Abstract

The present invention relates to an unmanned vehicle, characterized in that when the steering control of the guideline system with high precision, it is possible to perform the steering control in relation to the traveling speed, the current steering angle by using a purge control device A signal, a traveling speed signal, and a departure signal from the guide line are input, and for the departure signal, a time differential signal is also created second.

The membership function is prepared in advance for each of these signals and the final values of the steering angle command signal and the speed control command signal, and based on these, the fuzzy inference is performed to output the optimum steering angle command and the speed control command.

This method works steering control and speed control in driverless car.

Description

Steering Angle and Speed Control Device of Unmanned Vehicle

1 is a schematic configuration diagram showing a steering angle and a speed control apparatus for an unmanned vehicle according to an embodiment of the present invention.

2 to 10 are diagrams for explaining the embodiment, respectively.

11 is a schematic configuration diagram showing a conventional unmanned carrier.

12 is a schematic configuration diagram showing a steering angle control device for the unmanned vehicle.

FIG. 13 is a schematic configuration diagram showing a speed control device for the unmanned vehicle. FIG.

* Explanation of symbols for main parts of the drawings

1: unmanned carrier 2: full text

3: steering motor 4: driving motor

6: steering angle detector 9: guide line

11: Mark Detector 12, 13: Amplifier

14 differential amplifier 18 drive circuit

19: control circuit 21: generator

25: steering angle detector 27: purge control device

28: preprocessing unit 29: purge inference unit

30: purge rule

The present invention relates to a steering angle and a speed control device for an unmanned transport vehicle running independently while detecting a guide line installed on a driving path.

In recent years, with the development of FA (Factory Atomation) such as factories, many automatic transport systems using unmanned transport vehicles have been introduced.

Steering angle control of the unmanned vehicle in such a system is mainly performed by a sensor attached to the vehicle body to detect the deviation from the guide line laid on the driving path and correct the deviation. The method of changing the is adopted.

On the other hand, in a curved part such as a curve, in order to perform a stable running, a method is employed in which a mark in which speed information is recorded is placed near the guide line before returning to the curve, and the speed information is read from this mark to change the speed. have.

FIG. 11 is a perspective view showing an example of a conventional unmanned vehicle 1, and FIG. 12 is a schematic configuration diagram showing a steering angle control system of the unmanned vehicle 1, and FIG. 13 is a schematic configuration diagram showing a speed control system of the unmanned vehicle 1. FIG.

First, in FIG. 11, 2 is a steering motor for setting the steering angle of the steering wheel 2, 3 is a driving motor for driving the steering wheel 2, 4 is a driving motor for driving the steering wheel 2, 5 is a control box, and from the steering angle detector 6 Reads the output signal of and controls the steering motor 3 according to this signal.

The steering angle sword 6 is formed in a substantially T-shape as shown in figure, and its proximal end is attached to the drive shaft of the steering motor 3, and it is made to swing in the horizontal direction according to the movement of the drive shaft.

In addition, detection coils 7a and 7b are attached to both ends of the distal end of the steering angle detector 6, whereby the detection of the magnetic tape (guide wire) 9 attached to the eighth path is performed.

At this time, the detection coil 7a is attached to the right side with respect to the traveling direction A of the vehicle body, and the detection coil 7b is attached to the left side with respect to the same direction A as shown.

The detection of the guideline 9 by the detection coils 7a and 7b uses the electromotive force generated by moving these detection coils 7a and 7b into the magnetic field of the guideline 9. As the electromotive force is separated from the guideline 9, Becomes smaller.

10 is a rear wheel, and rotation is attached freely.

11 is a mark detector and reads speed information from a mark (not shown) provided on the traveling surface near the guide line 9. FIG.

Next, in Fig. 12, 12 and 13 are amplifiers, respectively, and amplify the electromotive force induced by the detection coils 7a and 7b.

14 is a differential amplifier, and outputs a difference (hereinafter, a deviation signal) of the output voltages of the amplifiers 12 and 13.

At this time, the output of the steering angle detector 6 is negative when it is off to the left side with respect to the guide line 9, and when the steering angle detector 6 is off to the right, it is positive. Off to the right, when the outputs of the amplifiers 12 and 13 become 4v and 1V, the output becomes 3V.

The deviation signal output from differential amplifier 14 is supplied to differential circuit 15 and to proportional circuit 16 at the same time.

In the differential circuit 15, the time differential of the deviating signal is performed to obtain a deviating direction (the direction in which the vehicle body is deviated).

The output signal from the differential circuit 15 and the output signal from the proportional circuit 16 are added by the amplifier 17, resulting in (e.g., deviating to the left with respect to the induction line 9 and also to the left). Signal) is supplied to the driving circuit 18.

The steering motor 3 is controlled to correct the deviation by the drive circuit 18, and the steering angle of the steering wheel 2 is determined.

Next, in Fig. 13, 19 is a control circuit for controlling the rotational speed of the traveling motor 4, and the converter 20 is capable of setting the speed in four steps.

The setting of the converter 20 is made by the speed information detected by the mark detector 11.

21 is a generator and generates voltage according to the rotational speed of the traveling motor 4.

This generated voltage is supplied to the control circuit 19 as a speed feedback signal.

By the way, in the above-mentioned conventional unmanned vehicle 1, since the steering system and the speed are controlled by the control system which set separately, there existed a problem that a circuit became complicated.

Moreover, in the curve, since the vehicle is to be constantly driven at the speed determined according to the steering angle control ability at the most urgent place, there is a problem that the running efficiency does not increase.

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and the steering angle of an unmanned carrier vehicle which can be controlled by a control system having a common steering angle and a speed, and which can change the traveling speed on a curve according to the steering angle, and It is an object to provide a speed control device.

The present invention provides detection means for detecting the deviation of the guide line laid on the driving path, calculation means for calculating the deviation direction by time-differentiating the deviation signal output from the detection means, and detecting the steering angle of the wheel. And a steering angle detecting means for detecting a traveling speed, and a traveling speed detecting means for detecting a traveling speed. And a means for controlling the steering angle and the driving speed of the wheel according to the result of the inference.

According to the said structure, the deviation | deviation with respect to the guide line of an unmanned carrier is detected, and the direction of this deviation is calculated | required by calculation.

Further, the steering angle of the steering wheel is detected by the steering angle detecting means, and the running speed is detected by the speed detecting means again.

Then, purge inference is performed in accordance with the off-road, the off-direction, the steering angle, and the traveling speed at the present time, so that the steering angle manipulation amount and the speed control amount are obtained.

Then, the steering angle and the traveling speed are controlled in accordance with the operation amount obtained as a result of this calculation.

EMBODIMENT OF THE INVENTION Hereinafter, the Example of this invention is described with reference to drawings.

1 is a schematic configuration diagram showing a steering angle and a speed control apparatus for an unmanned vehicle according to an embodiment of the present invention.

Incidentally, in Fig. 11, the same reference numerals are given to the parts in common with Figs. 11 to 13 and the description thereof is omitted.

In this figure, 25 is a steering angle detector for detecting the steering angle, and is attached to the drive shaft of the steering motor 3.

The output signal of the steering angle detector 25 is amplified by the amplifier 26 and then supplied to the purge controller 27.

The purge control device 27 is configured as a preprocessing unit 28, a purge inference unit 29 and a purge rule unit 30, and the preprocessing unit 28 is a deviation indicating the deviation of the induction line 9 according to the output signal of the differential amplifier 14. The signal ΔD and its time differential Δ ² D are obtained and supplied to the purge inference unit 29, while the output signal of the steering angle detector 25 is spread to the current steering angle G and the current speed V which is the output signal of the generator 21. Supply to reasoning unit 29.

The purge inference unit 29 performs purge inference according to the purge rule (described later) at the deviation signal ΔD and the time differential Δ ² D, the current steering angle G, and the current speed V supplied from the preprocessor 23. Then, the steering angle operation amount DELTA U and the speed control DELTA S are obtained.

At this time, the purging rule is determined by a personal computer, such as ΔD = L, Δ ² D = L, G = L, V = PS, ΔU = PB, ΔS = NS (that is, deviation from the guide line 9). If the left side, the time differential of the deviation is to the left, the current steering angle is off to the left, and the current speed is a little faster, then turn the steering angle to the right and slow down a little.) Remember to fill in the fuzzy reasoning unit 29.

Here, the membership function of the deviation signal ΔD is shown in FIG. 2, the time derivative of the deviation signal △ ^2D is shown in FIG. 3, the membership function of the current steering angle G is shown in FIG. 4, and the steering angle control command. The membership function of is shown in Fig. 5, the membership function of the current speed is shown in Fig. 6, and the membership function of the speed control command is shown in Fig. 7.

In these figures, the upper and lower limits are both +1 for the sake of simplicity.

The symbols L, Z, R, NB, NM, NS, ZO, PS, PM, PB, and PL are labels of membership functions, respectively. In this embodiment, all of the triangle functions are used.

In addition, the meaning of the label of each membership function in a figure is as follows.

① Membership function of the escape signal △ D

L is off to the left of the guide line 9.

Z: It is almost center of guideline 9.

R is off to the right of the guide line 9.

② Time derivative of escape signal △ ² D membership function

L: It is moving leftward.

Z: The deviation is almost constant.

R: It is moving away in the right direction.

③ Membership function of the current steering angle G

L: It is bent to the left.

Z: Almost not bent.

R: bent to the right.

④ Membership function of steering angle control command

NB: Make a big turn to the left.

NM: Fold it halfway to the left.

NS: Turn small to the left.

ZO: Almost don't shoot

PS: Turn small in the right direction.

PM: Turn halfway in the right direction.

PB: Make a big turn in the right direction.

⑤ Membership function of current velocity V

PB: Very fast

PL: Medium speed

PS: A little faster

ZO: The speed is almost zero.

⑥ Membership function of speed control command

PS: Increase speed a bit.

ZO: Almost no increase in speed

NS: Slow down a bit

In addition, the purge control rule at the current steering angle G = L is shown in FIG. 8, the purge control rule at the steering angle G = Z is shown in FIG. 9, and the purge control at the steering angle G = R is shown in FIG. The rules are shown in FIG. 10, respectively.

In these diagrams, the zero direction deviation signal DELTA D and the time differential DELTA ^2D of the deviation signal DELTA D are shown, and the horizontal direction represents the current velocity V. FIG.

Also, there are 36 purge control rules. For example, the rule 1 at the steering angle G = L is "L, L, ZO", and the steering angle operation amount? U is "PB" and the speed control? S is "-"to be.

In addition, "-" means that it takes the same value as the set value, when control is performed previously.

Rule 2 is "L, L, PS", where steering angle operation amount DELTA U is "PB" and speed control DELTA S is "NS".

In addition, rule 3 is "L, L, PM", steering angle operation amount ΔU is "PB", speed control ΔS is "NS", and rule 4 is "L, L, PB", steering angle operation amount △ U is "PB" and speed control DELTA S is "NS". Hereinafter, as in FIG.

In the fuzzy inference method, the conventional "MAX-MIN logical" is used conventionally, and the "central method" is used as a determination method of an output.

By these methods, the steering angle operation amount DELTA U and the speed control DELTA S are obtained.

In addition, the detailed description of the fuzzy inference method by "MAX-MIN logical" is described in detail in the specification (the steering angle control device of the unmanned carrier) already filed on March 30, 2017 by the present applicant It is described.

In addition, the fuzzy inference method and the output determination method may employ | adopt methods other than the above.

The purge inference unit 29 spreads the deviation signal ΔD at the current steering angle (G = L, Z, R), the time derivative Δ ^2D of the deviation signal ΔD, and the current velocity V. The steering angle operation amount? U obtained here is amplified by the amplifier 33 and then supplied to the driving circuit 17.

In this way, the steering motor 3 is controlled to set the steering angle.

On the other hand, the speed control ΔS is amplified by the amplifier 34 and then supplied to the control circuit 19.

By doing so, the speed control of the traveling motor 4 is performed to set the speed.

In the above embodiment, the case of the forward of the unmanned vehicle 1 has been described, but in the case of Fuji, the steering angle and the speed are replaced with the steering sensor (not shown) attached to the rear of the unmanned vehicle 1, as in the case of the forward. Doing control of them goes without saying.

As described above, according to the steering angle and speed control apparatus of the unmanned vehicle according to the present invention, the fuzzy inference is performed on the deviation from the guide line, the time derivative of the deviation, and the current steering angle and speed. Therefore, the steering angle and the speed are controlled by the deviation from the guide line, so that the running efficiency is improved as compared with the conventional method of driving the curve at a constant speed.

This is effective when driving a route with many curves.

In addition, since there is no need to provide a mark for speed designation before entering the curve, the mark is unnecessary and the effect of lowering the price can be obtained.

Claims (1)

Detect means for detecting the deviation of the guide line laid on the driving path, Computation means for calculating the deviation direction by time-differentiating the deviation signal output from the detection means, Steering angle detection means for detecting the steering angle of the wheel And a traveling speed detecting means for detecting a traveling speed, and performing a fuzzy inference on the deviation and deviation directions, steering angles and driving speeds at the present time in an unmanned transport vehicle which is self-driving along the guide line. And a steering means for controlling the steering angle and the traveling speed of the wheel according to the inferred result.