JPS604950B2 - Mobile position detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mobile body position detection device for constantly monitoring the current position of a mobile body such as a crane moving on a fixed travel path from a ground-fixed side.

Conventionally, absolute position detection devices that utilize guide wires have been proposed, but there are problems such as insufficient detection accuracy.

The present invention has been made in view of this point, and will be explained in detail below using examples. FIG. 1 is a diagram showing the configuration principle of an example of a mobile object position detection device according to the present invention, and in the figure, 2 and 3 are two-frequency signal generators (transmitters) and transmitting antennas mounted on the mobile object, respectively. or transmitting coil, others belong to fixed equipment. 1 is a position detector, 4
and 5 are inductive wire (antenna) couplers, which include band-wave antenna couplers (with center frequencies of 〆 and 〆2, respectively).
BPF) are combined.

6 and 7 are a pair of parallel two-wire guide lines extending along the traveling path of the moving object, and are A, B, C, D, etc. along the traveling path. In this example, the process of bringing the two lines very close to each other and separating them by a certain distance d is repeated for each small section such as .

8 and 9 are terminal resistances of the guide wires 6 and 7, respectively.

It is assumed that the antenna 3 approaches the guide wires 6 and 7 and moves parallel to the plane of the guide wires, and also receives two frequency signals from the transmitter 2. Assuming that the outputs of antenna 3 and antenna 2 are simultaneously radiated from antenna 3 with the same magnetic field strength, the signal voltage from antenna 3 increases greatly in sections A and C of guiding wire 6 when the moving body moves. In sections B and D, the guide line 2
Because the lines are close together, the signal voltage yield is much higher than in sections A and C. In the guidance line 7 of the aircraft, the induced voltage was large in sections B and D, and extremely small in sections A and C. In addition, if the two-wire approach section of the guide wire is composed of 4 pitches, lacquered wires, the induced voltage can be considered to be zero in practice. Now, the line currents due to the voltages induced in the induction wires 6 and 7 are guided to the couplers 4 and 5, respectively, but from the coupler 4, the frequency . From the coupler 5, only the component of frequency 2 is extracted and sent to the detector 1. Note 4,5
The coupling insertion loss of both couplers is assumed to be equivalent, so that the induced voltage ratio of the inductive wires 6 and 7 is directly transmitted to the detector 1. Further, although the frequencies Na and Na2 may be arbitrarily selected, it is desirable in the design of the detector that the frequencies be as close as possible so that they can be separated by a bandpass filter in the coupler. FIG. 2 is a block diagram of a more detailed configuration example of the position detector 1.
The position sensor 1 includes three functions 10, 11, and 12.

1 0 is amplifier A, and from couplers 4 and 5, ``2 of 2
Amplify frequency components to the required level with the same amplification degree.

Reference numeral 11 denotes a common amplitude limiter (COML) for two frequencies, which limits the amplitude of the summed synthesis level of the two-frequency inputs from the amplifier A to a constant value.

12 is a frequency discriminator (DIS) that selects the differential synthesis type of the frequency discriminator (DIS), and the frequency discrimination characteristic that matches the center frequency (denoted as "o") of the two, and the zero output point at the center. It can also be called a vessel.

Then, an output corresponding to the input level difference of each component of inputs Na and Na2 from COML to this DIS is obtained at the output 13, and address detection is performed as described later. Please note that COML
A common AGO can be used in place of the frequency limit and na. It is generally undesirable to provide each of the two amplifiers separately, and the deviation value of the amplification degree of each individual amplifier deteriorates the accuracy of the apparatus. Next, a position detection operation when a moving body moves will be explained.

In FIG. 1, it is assumed that the transmitting antenna 3 of the mobile body moves on a two-dot chain line a along the travel route. If the moving object is, for example, in the center of section A, the signal from the antenna 3 is strongly induced in the guide wire 6, but only a small induced voltage is generated in the guide wire 7. If the moving object is located in the center of section 8, for example, the signal from antenna 3 will be strong on guide wire 7, and the signal on guide wire 6 will be strong.
is only slightly induced. FIG. 3 is a level diagram of each part in FIG. 2, and the 4th and 5th inputs are the input levels e from the guide lines 6 and 7 of the couplers 4 and 5, respectively, and their output levels are also similar to this. Note that the moving objects are A, B...
At the dividing point of each section (the point where the interval between two guide wires changes), due to the matching characteristics of the antenna 3 and each guide wire, a sudden change in the input level e cannot be obtained, and the forehead slope characteristic as shown in the figure. However, if the shapes sandwiching the dividing points of each concession line are similar, coupler 4
, 5 have almost the same inversion characteristics. As the mobile object moves, the inputs of the couplers 4 and 5 change as shown in Figure 3, and the outputs of the couplers 4 and 5 also change in a similar way. After being superimposed and linearly amplified, the common limiter 11 suppresses the larger amplitude of the two input frequency components compared to the smaller amplitude, and the combined level is controlled to a constant amplitude as an output. A waveform such as the output 11 in FIG. 3 is sent to the frequency discriminator 12.

For example, the frequency discriminator 12 outputs a negative voltage (1 e) if the input is a frequency limit, and a positive voltage (10 e) if the input is a frequency limit of 2.
At the dividing point of the yield line, the output becomes zero. This output 1
As is well known, 3 can be converted into digital symbols 1" and 0. Above, we have explained the basic operation when sending a signal from a moving object and detecting a position on the fixed side. An example of the case where detection is performed will be explained. Fig. 4 is a diagram showing a configuration example of the device of the present invention, where the sections are A, B, C, and D4 guest rooms, and the only equipment on the mobile side is the antenna 3, and the transmitter 2 is omitted from the diagram. did.

In this case, if 6 and 7 in FIG. 1 are considered as one pair, the guide wires to be laid out along the moving body are two pairs, that is, 6a, 7a, and 6.
b and 7b are used because the binary code of the address given to the section A to D is 2 bits, so if a 3-bit code is given, 3 pairs of guide lines can be laid. . In the case of Fig. 4, since it is 2 bits, the pattern of each guide line is determined according to the address of each section (the bottom row of the figure), and 6a, 7
Since a corresponds to the first bit and 6b and 7b correspond to the second bit, 6a and 7a are the division points of B and C, and 6b
and 7b cross-invert the gain of the induced electromotive force at each division point of A and B and C and O. Further, 14 and 15 are detectors including all of the couplers 4 and 5 and the position detector 1 in FIG. 4 as the moving object moves? It will be easily understood that the output and the output are obtained according to the explanation of FIGS. 1 to 3. It should be noted that the antenna 3 only needs to apply a frequency limit of approximately the same strength and a magnetic field of the same strength to all the guiding wires facing each other, one or more antenna coils are used, and the group of yielding wires is actually Attach printed wiring, for example, to insulating plates placed along the road, and
Alternatively, electric wires or metal strips may be attached according to the designed pattern, making it easy to manufacture and install. Now, in the case of Fig. 4, the outputs of 20 and 21 indicate that there is a moving object in each section of 1, A if 1, B if 1, 0, C if 0, 0, D if 0, 1. Since the point can be accurately detected by utilizing the fact that the output 13 becomes zero as explained in FIG. 3, the position can be detected with high accuracy even if the length of the section is made small.

Furthermore, if such a configuration is used, even if the route is long, n
By providing a pair of guide wires and n number of detectors, it is possible to detect the position of a moving object with a small section distance and high segmentation accuracy. In reality, a display device or the like is attached to the position detection device that displays the address directly or by converting the output for each bit (me~2n output) into a 1-bo Hayabusa code, but these are well known and will not be explained here. has been omitted. As explained above, the device of the present invention not only detects the position of a moving object for each address, but also has high detection accuracy.

In other words, since the present invention uses a combination of a pair of intersecting parallel two-wire guidance lines that intersect at a section division point and an antenna on a moving body that is evenly coupled to these, "two-frequency induction near the division point" The amplitude balance of the voltage is always maintained well without being affected by changes in the relative position between the induction wire and the antenna.In addition, the two-frequency induced voltage is increased by a common intensifier, especially when the common amplitude limit is Since the amplitude is limited by the frequency discriminator, the output characteristics of each frequency discriminator centered around the center frequency of the two frequencies are made steeper, so the position detection accuracy is increased, and addresses can therefore be divided finely. Therefore, the present invention has great effects on the operation of automation systems such as remote control of moving objects.

[Brief explanation of the drawing]

FIG. 1 is a diagram of the configuration principle of the device of the present invention, FIG. 2 is a block diagram of a configuration example of the position detector in FIG. 1, and FIG. 3 is a level diagram of each part in FIG. 2.
FIG. 4 is a diagram showing an example of the configuration of the apparatus of the present invention. 1, 14, 15...Position detector, 2...Two-frequency generator (transmitter) of a mobile object 3...Transmission antenna of a moving object, 4,5... ......Coupler including band reactor, 6, 7, 6a, 6b, 7a, 7b...Induction wire, 8,9...Terminal resistor, 10...Amplifier, 11...Common limit, 12...
・Frequency discriminator, 13...Binary code output. Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] 1. A group of mutually parallel guiding wires with a logarithm equal to the number of bits of the address of the binary code given to each section of the traveling path, laid along the traveling path of the moving object, and It consists of a position detector connected to one end, a two-frequency generator placed on a moving body, and one or more transmitting antennas that provide the two-frequency magnetic field, and one pair corresponding to each bit of the above address. The parallel two-wire guide wires are laid in such a way that whenever the sign of the bit is reversed in each of the above sections, the two wires are separated and approached at a fixed interval in opposite phases, and each of the position detectors is a filter that extracts only one of the two frequency induced voltages for each of the pair of parallel two-wire induction wires, an amplifier that commonly amplifies the output of the filter for each of the induction wires; A movement characterized in that it is equipped with an amplitude limiter common to two frequencies and a frequency discriminator whose center is centered on the center frequency of the two frequencies, and outputs a binary code for each pair of guide wires to obtain the address of a moving object. Body position sensing device.