JPH0610771B2 - Driving system for unmanned vehicles - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a traveling system for an unmanned vehicle, and more particularly, to an unmanned vehicle guided by a guide line from one line to the other line at the intersection of the guide lines. The present invention relates to a traveling system of an unmanned vehicle capable of stably automatically turning.

[Prior art]

A small low-frequency current is supplied to the guide wire laid along the road surface, and the low-frequency current flowing through this guide wire is detected by a pair of left and right pickup devices mounted on the body of the unmanned vehicle, and the detection results of both pickup devices are detected. A traveling system for an unmanned vehicle is known in which a steering motor of a steering system of an unmanned vehicle is amplified by correcting the deviation signal of (1) to correct a deviation from the guiding line to stably drive the unmanned vehicle along the guiding line.

Further, in such an unmanned vehicle traveling system, at the intersection of the guide lines, when a transition is made from one line to the other, conventionally, an appropriate turn command is issued near the intersection along the one guide line. The unmanned vehicle receives the signal, and at this time, the steering motor is driven along a certain turning locus by a turning command generated by a program turning operation means such as a function generator provided in advance in the unmanned vehicle to move the unmanned vehicle to the other side. The method is adopted in which the turning transition is made to the line No. 2 and the turning transition is ended when a constant signal generated from a predetermined position along the other line is received. For example, in the automatic turning system disclosed in Japanese Patent Laid-Open No. 50-20477, a proximity body indicating a turning start point and a turning end point is provided on a traveling road surface, and a pair of unmanned vehicle side detecting a guide wire is provided. By providing the above-mentioned proximity sensor other than the pickup device, the start and end of the programmed turning operation are detected.

[Problems to be solved]

However, in the automatic turning system at the crossing point by the above-described conventional unmanned vehicle running system, the turning end point is detected particularly during the process from turning start to turning end. Machines such as the traveling road surface condition near each intersection and the traveling drive system and steering system of an unmanned vehicle are adopted because a method that depends on a single detection signal that one sensor provided on the vehicle side detects in close proximity is adopted. It is difficult to perform stable detection according to changes in the system accuracy, and there is a problem that the unmanned vehicle cannot be accurately positioned at the central position of the guide wire at the end of turning.

Therefore, the object of the present invention is to eliminate the instability caused by detecting the end of turning with a single signal when turning from one line to the other at the crossing point of the guide lines on the traveling road surface, and smoothing is eliminated. It is another object of the present invention to provide an unmanned vehicle traveling system improved so that the unmanned vehicle is positioned in the center of the guide wire.

[Solution]

In view of the above-mentioned object of the invention, according to the present invention, there is provided a traveling control system for an unmanned vehicle, which guides an unmanned vehicle by sensing with a pickup device provided in a pair of left and right guiding lines laid on a traveling road surface. When the unmanned vehicle automatically turns from the one guiding line to the other guiding line, the output deviation of the pair of pickup devices converges to a substantially zero value, so that the unmanned vehicle moves and aligns with the other guiding line. The first detection circuit capable of detecting that the unmanned vehicle has derailed from the derailed state since the added value of the output absolute values of the pair of pickup devices has risen from a low level value to a high level value. A second detection circuit capable of detecting that the unmanned vehicle has recovered, and an automatic turning movement of the unmanned vehicle based on a logical product of both signals of the transition alignment detection signal and the derailment return detection signal obtained from the first and second detection circuits. An unmanned vehicle traveling control system is provided, which comprises an unmanned vehicle and a turn termination detection circuit that issues a termination signal for terminating a line, and is obtained from the first and second detection circuits.
Since the end of turning is determined according to the logical product of the signals of the states, a smooth and accurate turning transition is achieved at the intersection.

Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings.

FIG. 1 is a block diagram of one embodiment in the configuration of various means forming a traveling system of an unmanned vehicle according to the present invention, and FIG. 2 is a plan view schematically showing a traveling locus of the unmanned vehicle on a guide line.

First, referring to FIG. 2, a guide wire a, a guide wire b, etc. are laid on the traveling road surface, and the unmanned vehicle 10 positions the frequency current flowing through these guide wires a or b on both sides of the guide wire. A pair of left and right pick-up devices 12,
14 to detect. In addition, the unmanned vehicle 10 has a guide line a
Alternatively, each unmanned vehicle 10 has a plate detection sensor 16 for detecting an operation instruction mark plate at an operation instruction point M arranged at a key position along the line b, and the result of reading the mark plate pattern from the plate detection sensor 16 The microcomputer 18 mounted on the unmanned vehicle 1 generates operation commands such as acceleration, deceleration, stop, turn, etc.
0 drive mechanism is mainly controlled. On the other hand, the steering mechanism of the unmanned vehicle 10 also receives a control signal at the time of turning transition at an intersection described later by the operation instruction signal of the microcomputer 18 described above. The steering motor (not shown) is rotated forward and backward based on the detection signal, and the unmanned vehicle 1
A configuration is provided in which lateral displacements or deviations from the guide line in the 0 traveling direction are corrected and the vehicle is guided in the correct traveling direction. In FIG. 2, reference numeral 20a indicates steered wheels of the unmanned vehicle 10, and 20b and 20b indicate driving wheels.

With the configuration described above, at the intersection of the guide line a and the guide line b, when the unmanned vehicle 10 traveling on the guide line a reaches the vicinity of the intersection, when the turning transition to the guide line b is necessary, The operation instruction point M described above is arranged in the vicinity of the intersection, and the unmanned vehicle 10 reads from the mark plate pattern of the operation instruction point M that the vehicle should turn to the guide line b as an operation instruction. Then, when the program steering activation command generated from the microcomputer 18, that is, the activation signal of the turning transition action that follows a fixed turning locus is received, the turning transition is started.

Next, with respect to the unmanned vehicle 10 having the single steered wheel 20a shown in FIG. 2, referring to FIG.
The configuration and operation of the traveling system for performing the turning transition to the guide line b will be described. Note that, in FIG. 1, the same reference numerals as those in FIG. 2 indicate the same components.

In FIG. 1, the detection signals of the pickup devices 12 and 14, that is, the induced electromotive voltage signals 12a and 14a are amplified and detected and rectified by the corresponding amplification and detection circuits 22 and 24, respectively. After the two signals 12a and 14a have passed through the amplification detection circuits 22 and 24, the deviation signals of the two signals are the same as those of the unmanned vehicle 10 with respect to the steering control unit 26 and the zero cross detection circuit 40, that is, the guide line a or b (see FIG. 2). It is applied to a circuit that detects the state where the lateral displacement reaches the central position and the lateral displacement becomes substantially zero. On the other hand, the added signal of both signals 12a and 14a is input to the derailment detection circuit 38, the unmanned vehicle 10 derails from the guide line a or b, and the derailment state is generated according to the level change of the detection signals of both pickup devices 12 and 14. Detect. Steering control unit 2
Reference numeral 6 denotes a switching circuit 28, an amplifier circuit 30, a drive circuit 32, a steering mechanism 34 including a steering motor, a turning signal generating circuit 36 for generating a constant steering signal at the time of turning transition, that is, a program steering signal or a spin turn signal. Including the latter, the latter turning signal generating circuit 36 is adapted to input the above-mentioned steering signal when the switching circuit 28 is switched by the start signal for turning transition. The turning transition end detection circuit 42 is a program steering or spin turn start signal 18a or 18b from the microcomputer 18 via the OR circuit 41.
Is inputted, both the derailment detection circuit 38 and the zero-cross detection circuit 40 are inputted with both the signal indicating the derailment recovery state and the signal indicating that the lateral displacement has become substantially zero. At this time, it is a circuit for outputting a detection signal of the end of turning transition to the microcomputer 18. As described above, the microcomputer 18 is provided for controlling the operation instruction of the unmanned vehicle 10. When the mark plate pattern for instructing the turning transition is read at the operation instruction point M on the traveling road surface, the program steering or Generates a spin turn activation signal.

In the traveling system having the above-described configuration, the switching circuit 28 of the steering control unit 26 of the pickup detection device 12, 14 from the amplification detection circuit 22, 24 while traveling along one of the guide lines a or b. The deviation signal is switched to be received, and the deviation signal is amplified by the amplifier circuit 30 and then the steering motor of the steering mechanism 34 is driven through the drive circuit 32 to drive the steering wheel 20a (second wheel) of the unmanned vehicle 10.
(Fig.) Is controlled so that the vehicle is self-propelled along a correct traveling path along the guide line a or b.

When reaching the vicinity of the intersection of the guide line a and the guide line b and reading from the mark plate pattern of the operation instruction point M (FIG. 2) that it is the operation instruction for turning transition, the microcomputer 18 executes the program steering or the spin. Generates a turn activation signal. The latter spin turn is a turning method in which the unmanned vehicle 10 turns at an intersection centering on the vertical axis without turning along the locus. However, the operation of the steering control unit 26 is substantially the same as the program steering. It is the same as, and both are already known.

When the microcomputer 18 issues the program steering signal for turning transition or the activation signal 18a or 18b for spin turn, the switching circuit 28 is switched to the turning signal generating circuit 36, so that the turning signal passes through the amplifier circuit 30 and the driving circuit 3 is driven.
2 is input and the turning transition control for the steering mechanism 34 is started. That is, in the case of the program steering, the unmanned vehicle 10 is given a certain turning action along the turning transition locus shown in FIG. At this time, it goes without saying that the deviation signals of the two pickup devices 12 and 14 input to the switching circuit 28 are disconnected by the switching circuit 28.

On the other hand, the program steering or spin turn activation signal 18a or 18b is also input to the turning transition end detection circuit 42 via the OR circuit 41 to put the circuit 42 into an operating state. When the action of turning transition is started, the unmanned vehicle 10 gradually turns, for example, from the guide wire a toward the guide wire b.
Therefore, the derailment detection circuit 38 once detects a decrease in the signal level in this turning process, and then detects a return from the derailment state again as the guide wire b is approached. Detect by. Therefore, when the derailment recovery state reaches a signal level indicating that one of the guide wires a has been on the other guide wire b, a detection signal is output to the turning transition end detection circuit 42. Further, the zero-cross detection circuit 40 is positioned when the unmanned vehicle 10 is positioned at a position aligned with the guide line b, that is, the guide line b is located at the center of the left and right pickup devices 12 and 14 after passing through the turning transition locus. A signal indicating that the deviation signals of the pickup devices 12 and 14 have become substantially zero, that is, a zero cross signal, is also output to the turning transition end detection circuit 42. Thus, the turning transition end detection circuit 42 generates a turning transition end detection signal when both of the two kinds of status signals are received. This detection signal is sent to the microcomputer 18
Is input to inform that the turning transition has been completed. As a result, the microcomputer 18 generates an operation command for executing a normal traveling state along the guide line b, and resets the program steering start signal or the spin turn start signal. As a result, the switching circuit 28 of the steering control unit 26 is switched to the normal traveling system again.

Although the above description has been made regarding the turning transition in the case of the unmanned vehicle 10 having the single steered wheel 20a, when the steered vehicle has two steered wheels, the steering control unit 26 becomes the respective steered wheels. However, it should be noted that the detection operation of the end of the turning transition, which is the gist of the present invention, is completely the same even though it is different in that it is provided.

〔The invention's effect〕

According to the present invention as described above, the end signal in the turning transition process is detected from the logical product of the two kinds of status signals of the transition alignment detection signal and the derailment return detection signal, and the turning transition is ended. When a turning transition is made from one line to the other guide line, the guide line after the transition is surely and smoothly positioned at the position centered on the pair of pickup devices, and therefore, when normal traveling is started again from there. It is possible to start traveling stably without causing hunting operation. In addition, a smooth turning transition can be achieved regardless of the size and size of the unmanned vehicle 10.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of various elements and circuits forming a traveling system for an unmanned vehicle according to the present invention, and FIG. 2 is a turning transition of an unmanned vehicle from one guide wire to another guide wire. FIG. 3 is a plan view schematically showing a trajectory and a configuration of an unmanned vehicle. 10 ... unmanned vehicle, 12, 14 ... pickup device, 20a
... Steering wheels, 22, 24 ... Amplification detection circuit, 26 ... Steering control section, 18 ... Microcomputer, 38 ... Derailment detection circuit, 40 ... Zero cross detection circuit, 42 ... Turning transition end detection circuit, a, b ... Guide line.

Claims (1)

[Claims] 1. A traveling control system for an unmanned vehicle in which an unmanned vehicle is guided to travel when a pair of left and right pickup devices senses a guiding line laid on a traveling road surface. A first detection circuit that can detect that the unmanned vehicle has transitioned and aligned with the other guide line because the output deviation of the pair of pickup devices converges to a substantially zero value when the unmanned vehicle shifts automatically. And a second value that can detect that the unmanned vehicle has recovered from the derailment state to the derailment return state because the added value of the output absolute values of the pair of pickup devices has risen from the low level value to the high level value. A turning circuit that issues an end signal for ending the automatic turning transition of the unmanned vehicle based on a logical product of both the detection circuit and the transition alignment detection signal and the derailment return detection signal obtained from the first and second detection circuits. A completion detection circuit, an unmanned vehicle travel system, characterized in that is provided in the unmanned vehicle.