JPS59136814A - Detector of guide line for unmanned guide truck - Google Patents

Abstract

PURPOSE:To discriminate a normal guide state from a runaway state by constituting two bridges with combinations of two coils, reference coils and resistance which are arrayed on the same plane and rectifying the outputs of both bridges to perform addition and subtraction. CONSTITUTION:Two rectangular coils wound into the same form are set adjacently to each other on the same plane as detection coils 21 and 22 respectively. The 1st and 2nd bridges are formed with the coils 21 and 22, reference coils 51 and 52 and resistances 71 and 72, and the current is supplied to both bridges from a high frequency current source 8. The outputs of these bridges are set at 0 when the coils 21 and 22 are distant away from a guide line 3, and the output signals are increased as the coils 21 and 22 get closer to the line 3. The outputs of both bridges are amplified 91 and 92 and rectified 101 and 102 to be applied to a subtractor 11 and an adder 12. The output of the subtractor 11 is defined as the zero potential output for guidance of an unmanned truck. While the output of the adder 12 is used as a signal for detection of the presence or absence of the line 3. Thus it is possible to discriminate a normal guide state from a runaway state.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is directed to converting a guide wire for an unmanned guided vehicle into a detector.

Conventionally, magnetic detection guidance type tatami mats using aluminum foil or iron plates as guide wires for unmanned guided vehicles have been guided so that the output of the unmanned guided vehicle's detector becomes zero, so the detector It was difficult to distinguish between a normal guidance state and a runaway state in which the guidance line deviated from the guidance line using only the output signal.

That is, in Fig. 1, 1 is a detector attached to an unmanned guided vehicle, 2 is two detection coils wound inside the detector l for magnetically detecting the guide wire, and 3 is aluminum foil and stainless steel foil. , a guide line made of iron foil, etc., 4 is the floor on which the unmanned guided vehicle runs, and the position of the guide line 3 is detected by the detector eye located a certain distance from the guide line 3 pasted on the floor 4, and the unmanned In order to guide the guide car, when the detector 1 is moved left and right with respect to the guide wire 3, if the guide wire 3 is located directly below the position where the two detection coils 2 are adjacent, the output will be zero, and
As shown in A in Figure 2, when moving to the left (-e), a negative output voltage (-■) is required, and when moving to the right (+e), a positive output voltage (+V) is required. . However, the movement of the detector l with respect to the guide wire 3 is large (so that even if the guide wire 3 deviates from the detection range of the detector l, the detector l will have a zero output, so the two detection coils 2 are adjacent to each other). It was difficult to distinguish between a case where the guide line 3 was directly below the position (normal guide state) and a case where the guide line 3 deviated from the detection range of the detector 1 (runaway state).

Therefore, as shown by B in FIG. 2, the present invention provides an output voltage that is obtained when the guiding wire 3 is within the detection range of the detector 1, and a zero output outside the detection range, at the same time as the guided signal. In order to distinguish between normal and runaway states,
Two detection bridge circuits are constructed with two detection coils wound side by side on the same plane as one side, and after rectifying the outputs from these two detection bridge circuits, addition and subtraction are performed using an addition and subtraction circuit. The subtracted signal is used as a zero position detection signal for guiding the unmanned guided vehicle, and the added signal is used as a guide line detection signal for detecting the presence or absence of a guide line.

An embodiment of the present invention will be described.

As shown in FIG. 3, two rectangular coils wound in the same shape are arranged on the same plane so that one side of the same length touches each other to form detection coils 21° and 22.

As shown in FIG. 4, the detection coil 21, reference coil 51, and balance resistor 61.62 constitute a first bridge, and the detection coil 22, reference coil 52, and balance resistor 71.72 constitute a second bridge. do. 1st
Power is supplied to the second bridge from the high frequency power supply 8, and when the induction wire 3 is away from the detection coil 21, 22, the output of the first and second bridges is zero, and the induction wire 3 is connected to the detection coil 21. The output signal is set to increase as the value approaches .22. The output signals from the first and second bridges are amplified by amplifiers 91 and 92, demodulated by rectifier circuits 101 and 102, and then sent to subtracting amplifier 1.
1 and then take the difference between the output from the first bridge and the output from the second bridge. The value of this difference is the value of the detection coil 21.
When the guide wire 3 is at the point where 22 touches @23, the output is zero, and as it moves away from it to the left and right, the output increases to positive or negative.
A zero position detection signal Ill having the characteristics is obtained. - By adding the output signals from the first bridge and the second bridge demodulated by the power and rectifier circuits 101 and 102 to the summing amplifier 12 and adding them, the guide wire 3 deviates from the detection range of the detection coils 21 and 22. B in FIG. 2, where the output from the summing amplifier 12 becomes zero and only the output signal from the summing amplifier 12 is obtained when the guiding wire 3 is within the detection range.
A guiding wire detection signal 121 having the characteristics is extracted.

As mentioned above, in the magnetic detection guidance method using aluminum foil or iron plate as a conductive wire, only the zero position detection signal, which is the guidance signal for guiding the unmanned guided vehicle, was conventionally used. For example, since it is possible to detect the presence or absence of a guide line, when the unmanned guided vehicle deviates from the first guide line, the unmanned guided vehicle can be stopped by the first guide line detection signal, which is the guide line detection signal, and the unmanned vehicle can be stopped. It is possible to prevent the guided vehicle from running out of control, and by cutting a portion of the guide line, it is possible to stop the unmanned guided vehicle at any desired location.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram showing the arrangement relationship between the detector and the guide wire.
The figure is a curve diagram showing the detection characteristics when the guide wire moves left and right with respect to the detector, FIG. 3 is an explanatory diagram showing the arrangement relationship of the detection coil in one embodiment of the present invention, and FIG. FIG. 2 is a circuit diagram showing a connection configuration in one embodiment. 1 is the detector, 2, 21 and 22 are the detection coils, 23 is the position where the detection coils 21 and 22 touch, 3 is the guide wire, 4 is the floor,
11 is a subtraction amplifier, 12 is a summing amplifier, 51.52 is a reference coil, 61.62.71.72 is a balance resistor,
8 is a high frequency power supply, 91.92 is an amplifier, 101.102
is a rectifier circuit, 111 is a zero position detection signal, and 121 is a rust conductor detection signal.Patent Applicant Fig. 1? ? Figure 2 Figure 3 Nj −← Fraud=75− 1～m −～121

Claims (1)

[Claims] One of the bridges is a detection coil in which two rectangular coils wound in the same shape are arranged on the same plane so that one side of the same length touches each other, and each of the two coils is combined with a reference coil and a resistor. the first and second edges respectively
The output from the first and second bridges is set to zero when each coil is away from the induction wire, and increases as the coil approaches the induction wire. The output signals from the first and second bridges are respectively amplified and rectified and then added to addition and subtraction circuits, and the added signals are used as a guide wire detection signal,
A guide line detector for an unmanned guided vehicle, characterized in that the subtracted signal is used as a zero position detection signal.