JPH02116907A - Running guidance device for unmanned car - Google Patents

Abstract

PURPOSE:To lay a guide line by a simple work by laying a guidance line, and also, providing an oscillator, a terminal which comes into contact with the guidance line, and a means for detecting a magnetic field generated by an electric conduction of the guidance line on an unmanned car. CONSTITUTION:A current is allowed to flow to a guide line 12 placed between terminals 17, 18 by an oscillator 19 for oscillating a high frequency. As a result, a magnetic field M1 is generated in the periphery of the line 12, by which a induced current flows to receiving coils 23, 24 loaded on an unmanned car. When the line 12 is positioned in the intermediate position of both the coils 23, 24, outputs of inducted currents of the coils 23, 24 become equal. Outputs of the coils 23, 24 are inputted to a comparator 27 through amplifiers 25, 28 and rectifiers 26, 29, respectively, a running position shift of an unmanned car is calculated in the comparator 27, and the speed of revolution of motors 4, 5 for correcting the shift is changed. In such a way, the unmanned car runs along the line 12.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a travel guidance device for an unmanned vehicle that is introduced in a warehouse or factory for the purpose of transporting articles.

[Conventional technology]

Conventionally, electromagnetic induction and optical guidance have been known as guidance methods for unmanned vehicles. The optical guidance method involves pasting highly reflective tape on the floor of the running path to form a line.
The unmanned vehicle illuminates the driving path, detects the line with a photodetector, and the unmanned vehicle travels along the line. In addition, with the electromagnetic induction method, electric wires are buried under the floor of the driving path, and the magnetic field generated by passing current through the wires is detected by a magnetic field detector mounted on the unmanned vehicle, and the unmanned vehicle moves along the wire. It is designed to run.

[Problem to be solved by the invention]

The two conventional guidance methods described above have the following disadvantages.

First, in the optical guidance method, the reflective line is easily soiled, and once it is soiled, there is almost no difference in the amount of reflected light between the line and the floor surface where the line is not attached, making it impossible to detect the line. There were factories where the interior had to be constantly cleaned, and what's more, it was impossible to introduce the optical guidance system itself.

Furthermore, in the electromagnetic induction method, it is necessary to bury the electric wire, which requires time and effort, and once the wire is buried, it is difficult to change the running route. Furthermore, in order to pass current, it is necessary to make the wires into a closed loop, and in order to pass current through the wires throughout the route, a high-output oscillator is required, and the control becomes complicated and costs increase. It was happening.

[Means to solve the problem]

In order to solve the above problems, an unmanned vehicle travel guidance device according to the present invention lays out a conductive guidance line on the floor along the travel path of the unmanned vehicle, and generates a current on the unmanned vehicle side. An oscillator, a conductive terminal connected to the oscillator and in contact with the guide line at least during running, and means for detecting a magnetic field generated by energization of the guide line were provided.

〔Example〕

Next, an embodiment to which the present invention is applied will be described based on the drawings.

FIG. 4 is a schematic plan view of an unmanned vehicle equipped with a travel guidance device according to the present invention. The unmanned vehicle (1) is provided with a pair of driving wheels (2) and (3) on the left and right sides at approximately the center in the longitudinal direction of the vehicle body, and the driving wheels (2) and (3) are equipped with driving motors (4) and (5).
) are directly connected to each other. The unmanned vehicle (1) moves straight forward or backward by rotating the left and right drive wheels (2) and (3) in the same direction at the same rotation speed, and turns by rotating the left and right drive wheels in the same direction at different rotation speeds. , left and right drive wheels (2
) (3) in the opposite direction at the same speed,
It is able to rotate and change direction at the same point.

The left and right drive wheels (2) and (3) each have the above-mentioned traveling motor (4).
) (5) In addition to brakes for deceleration or stopping (6)
(7) It has pulse generators (8) and (9) that detect the rotational speed of each of the drive wheels (2) and (3). (1
0) (11) is a guideline sensor, and the floor surface (
Guideline (F), which is a guidance line affixed to
12) Detecting the position.

(14) and (15) indicate a mark sensor to be described later, which reads a mark (16), which is a mark to be detected, attached to the floor surface (F) at the operation command position. Further, (17) and (18) are flexible terminals connected to an oscillator (19) mounted inside the vehicle body of the unmanned vehicle (1). Only one of the guideline sensors (10) (11) and mark sensors (14) (15) is activated depending on the direction in which the unmanned vehicle (1) is traveling.

(20) is a driven wheel supported by the vehicle body in the form of casters, and (21) is a bumper.

As mentioned above, there are two guideline sensors (10) and (11) after π, but the structure is similar, so we will only explain one guideline sensor (10) and the other (11).
1) will be omitted.

The guideline sensor (10) has a first receiving coil (23) and a second receiving coil (24) as shown in FIG. The first receiving coil (23) is connected to a comparator (27) via an amplifier (25) and a rectifier (26), and similarly, the second receiving coil (24) is connected to an amplifier (28) and a rectifier (29). It is connected to the comparator (27) via the.

The signal from the comparator (27) is sent to the left and right drive wheels (2) (3).
) Travel control circuit (30) for travel motor (4) (5)
<31) is done manually. In addition, the above rectifier (2
6) The signal from (29) is also input to the auto gain control amplifier (32), and the control amplifier (32) feeds back the amplification amount of both amplifiers (25) and (28).

Oscillator (27) IIJ frequency e UJ, tha 400KHz)
The oscillator (27) has a flexible terminal ( 17) Connected to (1g).

The flexible terminal (17) <IB) is conductive and has a brush-like shape. Flexible terminal (17
) (18) Since each of them is in contact with the guideline (12), the current generated by the oscillator (27) can only flow on the guideline (12) between the flexible terminals (17) and (18). ing.

The above-mentioned guideline (12) is attached to the floor using a conductive metal body, for example, aluminum tape. In addition, the installation state of the guideline (12) is such that the current flows only on the guideline (12) between the flexible terminals (17) and (18) as described above, so the guideline (12) itself needs to form a loop. do not have.

The mark (16) is a mark to be detected which is composed of a plurality of tuned circuits having different known tuning frequencies, and by changing the tuning frequency, the mark (16) can control the unmanned vehicle (1) to decelerate, stop, or stop. The instructions for turning right, turning left, etc. are changing. The mark sensors (14) and (15) read the instruction contents of the mark (16) and send the read instruction contents to the travel control circuits (30) and (31) of the travel motors (4) and (5).

Next, an unmanned vehicle (1) using the travel guidance device according to this embodiment
The running operation of the will be explained.

First, the flexible terminal (17) is connected by the oscillator (19).
(18) A current is passed through the guideline (12) between them. Here, an oscillator (19), flexible terminals (17) (18),
The guideline (1) between the flexible terminals (17) (18)
Since a closed loop is formed by 2), current can only flow within the closed loop. A magnetic field (M, ) is generated around the guideline (12) by the current flowing, and the magnetic field (Ml) causes the unmanned vehicle (1
) installed in the guideline sensor (10)
An induced current flows through the second receiving coils (23) and (24).

The output of the induced current flowing through the first and second receiving coils (23) (24) changes depending on the distance between the receiving coils (23) (24) and the guideline (12), and The maximum amount of output occurs when the guideline (12) is located, and the output gradually decreases as it moves away from the position directly below the guideline (12). Figure 2 shows this situation in the form of a graph, with the horizontal axis showing the guideline (12) position and the vertical axis showing the output of the induced current flowing through the receiving coils (23) and (24). The curve (Pl) represents the output of the induced current of the first receiving coil (23).
2) shows the output of the induced current of the second receiving coil (24). Guideline (12) connects both receiver coils (2
3) When located at the intermediate position of (24) (position shown by the two-dot chain line in FIG. 3), the outputs from both receiving coils (23) and (24) become equal.

Outputs from the first and second receiving coils (23) and (24) are input to a comparator (27) via amplifiers (25) and (28) and rectifiers (26 and 29), respectively. The comparator (27) calculates the travel position deviation of the unmanned vehicle (1), and a motor (4) for correcting the deviation.
(5) The rotation speed is changed. For example, if the guideline (12) is closer to the second receiving coil (24) as shown by the dotted chain line in Fig. 3 (actually, the guideline (11) is immobile, of course, and the unmanned vehicle (1) The movement causes the second receiving coil (24) to align with the guideline (12).
), the first and second receiving coils (
23) (24) Output from (Va) (Vb)
As is clear from FIG. 2, Va<Vb. On the other hand, if it were closer to the first receiving coil (23),
Va>Vb. Therefore both receiving coils (23)
By comparing the outputs from (24), the unmanned vehicle (1
) is located relative to the guideline (12) position.

In addition, since the amplification amount of the amplifiers (25) and (28) is feedback-controlled by the auto gain control amplifier (32), the unmanned vehicle (1) and in turn the guideline sensors (10) and (11) swing, causing the guideline ( This eliminates changes in the output of the induced current from the receiving coils (23) and (24) caused by approaching or separating from the receiving coils (23) and (24) in the vertical direction. For example, if the guideline sensors (23) (24) themselves are farther away from the floor than usual, the output from the receiving coils (23) (24) will decrease overall (as shown by the chain lines in Figure 2). ), the control amplifier (32) gives commands to the amplifiers (25) and (28) to increase the amount of amplification. As described above, the unmanned vehicle (
1) runs along the guideline (12), but there is a mark (16) affixed on the floor (F) at an arbitrary position.
The mark sensors (14) and (15) read the instructions contained in the marks (16), allowing the vehicle to stop, turn left or right, go sideways, go backwards, etc.

As can be seen from the above description, the travel guidance device for the unmanned vehicle (1) of the present embodiment forms a closed loop using the oscillator (19), the flexible terminals (17) and (18), and the guideline (12) between the terminals (17) (1g>). Furthermore, since the closed loop has a very short distance, the current flows efficiently, and the oscillator (19), which conventionally required a large output to flow the current throughout the guideline (12), has a small output. In addition, the guideline (12) itself no longer needs to be configured as a closed loop.

In addition, in this example, the flexible terminals (17) (18)
Although it has been explained that the guideline (12) is always in contact with the guideline (12), the same effect can be obtained even if the guideline (12) is in contact with the guideline (12) only while driving.

〔Effect of the invention〕

As is clear from the above explanation, according to the driving guidance device for an unmanned vehicle according to the present invention, a guideline can be laid with a simple operation, and the guideline will not become dirty and line detection becomes impossible. Furthermore, there is no need to form a closed loop.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing the configuration of the running transmission device for an unmanned vehicle according to the present invention, Fig. 2 is a graph showing changes in the output of induced current in the receiving coil due to changes in guideline position, and Fig. 3 is a receiving coil. FIG. 4 is a schematic plan view of an unmanned vehicle to which the present invention is applied. (1) Unmanned vehicle (10) (11) Magnetic field detection means (guideline sensor) (12) TS guideline guideline) (17) (18
) terminal (19) Oscillator (F) Floor (Ml) Magnetic field

Claims (1)

[Claims] A conductive guidance line is laid on the floor along the driving path of the unmanned vehicle, and an oscillator that generates a current is connected to the oscillator on the unmanned vehicle side, and the conductive line is in contact with the guidance line at least while driving. 1. A travel guidance device for an unmanned vehicle, comprising: a conductive terminal, and means for detecting a magnetic field generated by energization of the guidance line.