JPS63106014A - Detecting method for unmanned carrying vehicle - Google Patents

Abstract

PURPOSE:To surely detect the existence of an unmanned carrying vehicle with simple constitution, by obtaining an electrical output by detecting an a.c. magnetic field generated from a guide sensor of exciting type loaded on the unmanned carrying vehicle by an a.c. magnetic field detector provided on a road. CONSTITUTION:A guiding magnetic sensor 1 in a magnetic guiding system in which an exciting type sensor is used, is provided with an exciting coil 3 to magnetize a marker 2, and a detecting coil 4 to detect the magnetization of the marker 2, and those are arranged in a shielded case 5 only whose lower plane is opened. The a.c. magnetic field is radiated only to the lower plane, and a radiated magnetic field covers fully the marker 2. In this case, by arranging the a.c. magnetic field detector 6 on a traveling road, it is possible to sense the magnetic field radiated from the sensor 1 with the a.c. magnetic field detector 6 when the unmanned carrying vehicle on which the exciting type sensor 1 is loaded passes on the road, and to detect the approaching and passage of the vehicle 7. An induction coil, a Hall element, and a magnetic resistor, etc., are used as the a.c. magnetic field detector 6.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for detecting an unmanned vehicle from the road surface in an unmanned transportation system using a magnetic induction method.

[Prior art] There are various methods for unmanned vehicles used in unmanned transportation systems (for example, Japanese Patent Application Laid-Open No. 59-202512, Japanese Patent Application Laid-open No. 57-13020).
No. 0) has been developed and is already in practical use in factories. In conventional systems, a host computer determines the optimal route for the unmanned vehicle's next destination entered at the station, and gives instructions to the unmanned vehicle through a communication system installed at the station. In addition, arrival was confirmed by an unmanned vehicle at the destination station and communicating with the host computer. In this way, the route on the taxiway that an unmanned vehicle travels is generally managed by a host computer, which is rare.

[Problems to be Solved by the Invention] In recent years, systems that do not have a host computer have begun to appear. In this method, the destination is input directly into the unmanned vehicle, and the unmanned vehicle selects its own route according to its built-in map. Since this method does not have a host computer, the system becomes very inexpensive.

However, when this method is actually used, the means to notify nearby people of the arrival of an unmanned vehicle is to generate a sound, but is limited to emitting light. Therefore, under conditions where a station must be set up in a place where no sound should be emitted or where it cannot be seen, the method of notifying the arrival of an unmanned vehicle has become a major problem.

An object of the present invention is to provide a system that reliably recognizes the approach of a vehicle and generates an electrical output using a simple system.

[Means for Solving the Problems] The present invention provides an induction coil installed on a road surface that receives an alternating current magnetic field emitted from an excitation type guide sensor mounted on an automatic guided vehicle.
This is an automatic guided vehicle detection method characterized by detecting with an AC magnetic field detector such as a Hall element or a magnetoresistive element and obtaining an electrical output.

[Function] A magnetic sensor 1 for guiding in a magnetic induction system using an excitation type sensor generally includes an excitation coil 3 for magnetizing the marker 2 and a sensor for detecting the magnetization of the marker 2, as shown in FIG. The sensor has a detection coil 4 which is arranged in a shield case 5 with only the bottom surface open. The alternating magnetic field is emitted only to the lower surface, and the emitted magnetic field sufficiently covers the marker 2.

If the AC magnetic field detection device 6 is installed on the road surface as shown in FIG. 2, the magnetic field emitted from the sensor 1 will be detected when the automatic guided vehicle 7 carrying the excitation type sensor 1 passes over it. The alternating current magnetic field detection device 6 senses this and can detect the approach and passage of the transport vehicle 7. As the AC l'a lift detection device @6, an induction coil, a Hall element, a magnetic resistance, etc. are used.

[Example] Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a block diagram of an alternating current magnetic field detector 6 of a guided vehicle detection device using an induction coil as an example of detecting a guided vehicle according to the present invention. When the induction coil 8 receives a magnetic field generated from the excitation coil of the magnetic sensor, an induced voltage is generated. This induced voltage is received by a buffer 9, a filter 10 selects only the excitation frequency, and a rectifier circuit 11 converts it into a DC level change. Here, a suitable level comparator 12 performs a level comparison and outputs an ON-OFF electrical signal, which is used as a control signal to light up a signal lamp 13 as shown in FIG. Alternatively, a buzzer sound is emitted to notify the user.

Note that the filter 10 only needs to be used when there is a lot of noise at other frequencies. Further, the output may be directly linked to other control equipment. A Hall element or magnetic resistance can be used for the AC magnetic field detection part, but basically,
The signal processing after the filter is the same as for the induction coil, and a voltage application circuit is added to the Hall element and a bias circuit is added to the magnetic resistance.

As described above, since reliable detection can be performed with a simple structure, an extremely reliable guided vehicle detection device can be constructed.

[Effects of the Invention] As described above, according to the present invention, by detecting the presence of an unmanned vehicle, converting it into an electric signal, and notifying the user with a signal light or sound at the location where the user is present, the vehicle can be detected in a location where the driver cannot see the vehicle or where there is a loud noise. The arrival of an unmanned vehicle can be easily notified even in places where it is not possible to emit a signal, and this signal can also be used as an automatic door switch, allowing various applications to be realized at low cost. This is an advantage unique to a magnetic induction system using an excitation type sensor.

[Brief explanation of the drawing]

Figure 1 is a block diagram showing an embodiment of the detection device used in the method of the present invention, Figure 2 is a diagram showing the detection device of the present invention installed on a running road, and Figure 3 is the detection method of the present invention. 1 is a diagram showing the structure of an excitation type sensor used for.

Claims (1)

[Claims] (1) An automatic guided vehicle detection method characterized by detecting an alternating current magnetic field generated from an excitation type guide sensor mounted on the automatic guided vehicle with an alternating current magnetic field detector installed on the road surface and obtaining an electrical output. .