JPS6057010B2 - Mobile position detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a device that uses guided radio to detect the position of a crane, cart, etc. moving on a fixed travel path from the ground side. The number of addresses obtained is calculated based on the number of guiding wires laid to form the address code. The major feature is that it has been increased compared to the previous method.

Conventional guided wireless moving object position detection devices are given an appropriate binary coded address for each section into which the driving route is divided, and the address is divided into multiple sections corresponding to the number of digits (bits) forming this address code. A plurality of parallel two-wire guide wires that are crossed according to the address code at points, and a parallel two-wire guide wire that is parallel to these and are used to obtain a reference phase signal are laid along the running route, A transmitter of a specific frequency and an antenna coupled to a group of guide wires are installed on the moving body side, and the phase of the antenna input by each of the crossed guide wires is calculated using the antenna input by the reference phase signal guide wire as the reference phase input. A method has already been proposed in which the location of a moving object is detected as an address code by detecting the address code.
In this method, between the number of addresses N and the number n of two-wire induction wires, N<
, 2゛-'' is required, and for example, even if a group of guide wires with n = 10 are used, only 512 addresses can be obtained.The disadvantage is that the number of addresses obtained is small compared to the number of guide wires used. It was hot.

The present invention has been made to improve these drawbacks, and is characterized by the fact that it does not use a standard phase signal guide wire, and it is possible to obtain a larger number of addresses by using a fixed number of guide wires. Detection accuracy is high even in noisy areas, absolute addresses can be obtained immediately upon initial operation of the device, and the number of guide wires required is significantly smaller than conventional methods, especially when the number of consecutive addresses, that is, the number of sections is large. This greatly reduces the economic burden.

The present invention will be specifically explained below. The device of the present invention consists of a guide wire system laid along a running route, a moving body side facility consisting of an antenna and a transmitter (or transmitter) installed on the moving body, and a position detection system installed on the ground fixed side (referred to as a ground station). It consists of ground station equipment, mainly ground station equipment.

Figure 1 is a diagram showing an example of the configuration of equipment on the mobile side.
is F.

A frequency divider that divides the wave frequency into 1/m (m is an integer of 2 or more), 3 is a sine wave amplifier, and 4 is an amplitude or frequency modulator (
AM or FM (:I)MOD) carrier wave F. wave FO
/m wave modulation. 5 is an amplifier, and 6 is an antenna coil that is coupled face-to-face to the guide wire group.

As is clear from the figure, F from oscillator 1. The wave is frequency divider 2
The signal is input to the modulator 4, but the frequency divider 2 converts it to FO/m wave and increases it to the required level in the next stage sine wave amplifier 3. Widthed F. /m waves are sent to modulator 4 as modulation input. If amplitude modulation is used, the carrier frequency is F. The output of the modulator 4 subjected to amplitude modulation of the l'FO/m wave is output to the antenna 6 via the output amplifier 5. The structure of the antenna 6 will be explained later. Although the modulation is amplitude modulation, the same applies to frequency modulation. Next, the guide wire system will be explained.

FIG. 2 is a diagram showing an example of the configuration of the guide line system. Each section divided along the route is given an (absolute) address code using an alternating binary code (Gray code), and according to this code, the lines of the parallel two-wire guide line are assigned as follows: Find intervals and intersections. Figure 2 shows the case where the address code is 6 digits (6 bits) shown at the bottom of the figure. &=? It can be used to divide up to addresses. Also, (a) to (64) at the top of the figure.
) represents the section division point number, 11 and 10 are the 2nd guide line.
Line spacing is 11>1. We will call them wide spacing and narrow spacing, respectively. In the conventional device, if the address code is 6 digits, 6 to 7 guide wires are required, but in this example, only 4 guide wires are used. In other words, in the present invention, a set of two guide lines corresponds to a three-digit code, and the interval between the guide lines is changed from wide (11) to narrow (10) at the section division point, and the J2 line is crossed. I'm taking advantage of that. In the example shown in Figure 2, the guide lines in the top row and the next row are the second number in the address code.
They are in charge of the digit (21) and the third digit (7), and each guide line intersects at the section dividing point every time the code of that digit changes, but at the same time, the first digit of the address code ( In accordance with 2)), for example, if the code of t is ゜“1゛, the respective lead wire intervals of 7 and 7 are set to 11 and 1, respectively.If the code is ゜゜0゛, conversely, it is set to Z. ．． 7, each lead wire spacing is 1. 、． 11
As shown in the figure, the changes in 11 and 10 occur at odd-numbered positions such as (1), (3), (5), etc. of the segment division points. The i-digit code is 4k.
-2, 7 digit code is sha-4 (k is 1, 2, 3...
The intersection is performed at the position of the segmentation point number (integer of ...). In this way, 7, ? with two guide lines for each digit, 2 and 7, as described below. , 7, 3-digit addresses, 7=8 addresses can be divided. In the same way, two guide lines that are crossed according to the 7-digit and t-digit address codes are made into a set, and ? If the digit code is ゜゜1゛, set the lead wire spacing between the 7th digit and the t digit as 11 and 1. If it is ゜゛0゛, then the opposite is 1. If you go to 11, you will get F. 3-digit number division of 2l, t is possible, and Z. ．．
By using four guide lines 7, 7, and t, it is possible to divide 7=64 addresses as explained below. 7. The intersection of each guide line of t is 32k-16 and 64k-32, respectively.
The line spacing is changed at the segment point number 16k-8. Also, one end of each guide wire is terminated with a terminating resistor (not shown), and the other end is 10,
It is connected to the position transducer of the ground station through a coupler (eg a coupling transformer) such as 11, 12, 13.

Further, each of the above-mentioned guide lines is arranged parallel to the running path, for example, in four rows so as to overlap each other. Therefore, although there is a slight difference in the distance between the moving objects and the antenna, the difference in coupling loss is very small. For this reason, care must be taken to arrange the guide wires close to each guide wire, and to cancel out interference over the entire section between each guide wire by making the crossing sections evenly spaced and using an even number of sections. FIG. 3 is a diagram showing an example of the configuration of a position detector.

7 in the diagram is F. /m wave extraction circuit, 8 is the frequency FO'' (F
9 and 18 are position detection circuits, and 12 and 15 are π/2 radian phase shifters (P
S), 16, 17 are phase synthesizers, A, b, c,
d is Z. Combination guide lines of f, a″, b″, c″, d″
are the position detection address code outputs of the combination guide wires 7 and t. In this example, 71 and 72 in the circuit 7 are amplitude modulation detectors, and 73 is an F. /m wave synthesizer, 74 is F. /m wave bandpass filter (BPF), 81 in circuit 8 is phase discriminator (PD), 82 is low frequency? filter (LPF), 8
3 is a 1/m frequency divider, 84 is an FJ wave oscillator, 9 in circuit 9
1 (91a to 91c) are phase shifters (PS), 92 is P
Dl93 is an LPF. The operation of the circuit of FIG. 3 is as follows. Now, in this example, coupler 1 from each guide wire 7, 7
F the two outputs through 0 and 11.

/m wave extraction circuit 7 and detectors 71 and 72 generate amplitude envelope detection outputs. These two detection outputs are combined by a combiner 73 and then F by a BPF 74. /m waves are extracted. The input of the reference phase signal generator 8 is this extracted FO/m wave, and 81 to 84 constitute a PLL (face-locked loop) oscillation circuit. In other words, the output of the (voltage controlled) variable oscillator (VCO) 84 of the FO'' wave is converted to FJ/m by the frequency divider 83.
It becomes one input of PD8l. Another input of PD8l is F from BPF74. /m wave, the phase difference output of both hands is input as a control voltage to the VCO 84 through the LPF 82, and its oscillation frequency FJ is F. Synchronous control is performed so that FJ/m<5f0/m is equal to FJ/m<5f0/m. And F of VCO84. The wave output is from position detection circuits 9 and 1.
Sent to 8th. On the other hand, the inputs from the couplers 10 and 11 are also given to the phase synthesizer 16, but the input from the z-guide line remains unchanged! Input from transparent wire is phase shifter (PS) 12
For example, by shifting the (+)π/2 radian phase and combining the two, the inputs from the couplers 13 and 14 are similarly input to the phase synthesizer 17 from the 7-lead wire, and from the t-lead wire. The inputs are synthesized by shifting the phase by, for example, (+)I radians in PS15, and the outputs of synthesizers 16 and 17 are sent to position detection circuits 9 and 18, respectively. Next, the operation of the position detection circuit will be explained using circuit 9.

The FJ wave of the reference phase signal is input to the phase discriminator PD92a, and is also input to the phase shifter PS9la, where the phase is shifted by, for example, (+) I radian, and input to the PD92b, and the output of PS9la is input to PS9lb, where it is input to the phase shifter PS9la. Then, input the phase shifted by (+)I radians to PD92c and input it to PS9lc, and here (+)
The phase is shifted by I radian and inputted to the PD92d. That is, the phase discriminator PD92a. ．． PD92b. ．． PD92c
．． The reference phase signal input to PD92d is, for example, 01π
There are phase differences such as /4, π/2, and 3π/4 to discriminate the phases of the signal waves from the phase synthesizer 16, and the outputs are passed through LPFs 93a, 93b, 93c, and 93d to A, b, and c. , d. Note that the reference phase signal of FJ is F for its generation. /m wave extraction circuit 7 and FJ
Since the wave generating circuit 8 is used, the combining circuits 16 and 1
In many cases, the phase does not necessarily match the output wave of 7.
It is actually necessary to insert a phase correction circuit on the output side of the signal generation circuit 8 to correct the ideal phase relationship. The operation of the circuit 18 is also exactly the same as that of the circuit 9.
Each output of d'' is obtained.This is the last explanation, but the position detection operation will be explained next.First, a mobile object equipped with a transmitter and an antenna as shown in Fig. 1 moves the antenna as shown in Fig. 2. When moving while connected to the guiding wires of the structure, the voltage induced in each guiding wire is guided to a position detector as shown in Figure 3 and converted into an address code, but Figure 4 is similar to Figure 2. Figure 5 is a vector showing the phase and magnitude of the induced voltage when the induced wire is configured, and the combined phase and address code using an alternating binary code. Figure 5 is a vector showing the operation of the phase synthesizer in Figure 3. 6 and 6 respectively show phase relationship diagrams of the phase discriminator PD of the position detection circuit in FIG. 3.Now, 7.
The guide wire has wide wire spacing (11
), narrow (10), a guided output as shown in the vector of FIG. 4 is generated. That is, the output is large in the interval 11, and the output is small in the interval 11. It can also be seen that the phase of the output becomes reversed each time it passes through an intersection point.
next! The output of the guiding wire is transferred to the phase shifter PSl as shown in Figure 3.
Since the phase is shifted by +I radian at 2, the output in FIG. 4 is shown as a vector after the phase shift. Note that the coupling loss between the antenna and the guide wire is inversely proportional to the line spacing of the guide wires, so
As shown in Fig. 1, the antenna 6 is composed of, for example, two coils, and the distance between their centers is made larger than 11).
When placed so as to face each line, 10〆1
If it is 1/2, the above coupling loss in 11 sections is 1. The coupling loss in the section is 112, and in the z-guide line, for example, the magnitude of the vector is 1a1/2 with the phase reversed.
≠71/2. Next, the output of the z-guide line and the output of the 7-lead line are phase-shifted by π/2 and are phase-combined in the phase synthesizer 16 shown in Fig. 3, as shown in the vector diagram of Fig. 5. a1 and B in Figure 4. is input and the phase composite vector φ
1, and from the original b1 vector ψ2, i0 and Kg
As the moving body moves, F is synthesized for each section as a vector ψ3. The phase of the waves changes one after another. In the example in Figure 5, if the moving object moves from section (0) to section (8), the composite phase vector rotates from φ1 to φ8, and then if it moves from section (8) to section (16), the guided phase vector rotates from section (8) to section (16). As is clear from the configuration, the composite phase vector rotates from ψ8 to ψ1 in the opposite manner to the above. Since eight phases, that is, eight position addresses are generated using the two guiding wires Z and 7 in this way, PS12 and PS16 can be collectively called an eight-phase synthesizer. Then, the phase synthesized signals of ψ1 to ψ8 corresponding to the coupling positions of these mobile antennas are sent to the phase synthesizer 16.
The signal is output from the position detection circuit 9 and input to the position detection circuit 9. This circuit 9
The reference phase signal of the other FJ is input from the circuit 8,
If the phase discriminator PD92a receives a phase signal of 0 as shown in FIG. Phase discrimination is performed between ψ1 to ψ8 for each existing section, that is, for each section where the antenna is coupled, and outputs as A, b, c, and d through each LPF. Table 1 below shows a code conversion table for a code converter (not shown) that converts this a-d output into an address code. ψ1, ψ
2, ψ7, ψ8 (see a in Table 1 and Figure 5) are output as ゜゜1゛, and ψ3, φ,, ψ,
, φ6 are output as "゜0゛".Similarly, the phase discrimination outputs when the reference phase signal is +π/4, +π/2, and +3・π/4 are as shown in B, c, and d in Table 1. Therefore, for example, in the section of the composite phase vector ψ1, A, b, c,
It can be seen that the output of d is 1110 and 1111 in the interval ψ2. Note that the signal guided from the antenna and phase-combined is F. Since the amplitude components of /m waves are superimposed, each phase discriminator 92 is F. It generates a superimposed output of /m waves, but it is F by the LPF93. /m wave is removed and the phase discrimination DC output of ψ1 to ψ8 in each section is A,
Output as b, c, d. Also, A, b, c in Table 1
, d can easily be outputted using a code converter to output eight phases as shown by ABC on the right side as an address code of a 3-bit alternating binary code. In this way, since the distance between codes in adjacent sections of both the Abcd code and the N°C code is 1 bit, generation of an error address is suppressed even when passing a dividing point. 7 and T
O) The same is true for the guide line, and as shown in Figure 4, in the section (a) to (8), the phase composite vector is ψ,,
(8) to (16) section: ψ2 (16) to (24) section: ψ3 (24) to (32) section: ψ4 (32)
~ (40) interval ψ5 (40) ~ (48) ψ6
(48) to (56) is φ, and (56) to (64) is ψ8, which is input to the position detection circuit 18 in FIG.
Input as in the case of 0, +7r/4, +π/2, +
The phase of the phase composite wave is discriminated at a phase of 3π/2, and outputs a'', b'', C'', and d'' shown in Table 1 are generated.

If you send this to a code converter, you will get the A″B″C″ codes in Table 1, so ABC for the division points (1) to (64)
It can be seen that a 6-bit address code can be obtained by combining NB"C". The above example is a combination of two sets of parallel two-wire guide wires that give classification codes to the 7 classification sections, but in this method, the total number of guide wires is n, and the section Number = If the number of addresses is N, then N = 2n + f (n is 2
(even numbers above), but if n is an odd number n'', two guiding lines of n''-1 constitute a 3-bit code as in the case of an even number, and the remaining one guiding line has 2 bits by crossing. If the value information is expressed, N=2(n''-1も(312)×2).In the conventional method, for example, to obtain N=51 tomorrow, 512=? and 10 guiding lines are required. It can be seen that there is a significant savings when n + 艮 = 9 to n = 6. In addition, in the present invention, in order to improve the detection accuracy of section division points, two lines of the guide line intersect at the division points. The phase of the induced voltage will change by 180 lines (π radians) when the antenna is applied to As a result, the phase shift of the phase-synthesized signal wave occurs sharply at the dividing point, making highly accurate position detection possible.

Next, an example of an antenna installed on a moving object is shown in Fig. 1. If a loop-shaped coil antenna is used, coupling in a direction perpendicular to the guiding wire will occur at the bent part, resulting in a phase change before and after the dividing point. Disturbance detection accuracy decreases.

Therefore, in the present invention, it is suitable to use, for example, a pair of coil antennas with magnetic cores, which do not have the above-mentioned connection at the right angle but are connected in a direction parallel to the guide wire. As explained in detail above, the device of the present invention significantly reduces the number of guide wires, which generally increase installation and maintenance costs in proportion to the number of addresses, and although the position detection circuit becomes somewhat complicated, overall It is extremely economical.

Furthermore, when automatically controlling cranes, trolleys, etc. equipped with this device, the location can be detected on the ground with high precision as an absolute address, which greatly helps improve control reliability.

[Brief explanation of the drawing]

Figure 1 is an example of the configuration of equipment mounted on a moving body, Figure 2 is an example of the configuration of a guide line group, Figure 3 is an example of the configuration of a ground-side position detector, and Figure 4 is the same as in Figure 2. FIG. 5 is a vector diagram showing the operation of the phase synthesizer in FIG. 3, and FIG. 6 is a phase relationship diagram of the phase discriminator 92 in FIG. 3. . 1...Oscillator (FO wave), 2,83...
・Frequency divider, 3, 5...Amplifier, 4...
Modulator, 6...Antenna, 7...FO
/m wave extraction circuit, 8... Reference phase signal generation circuit, 9, 18... Position detection circuit, 10, 11, 13
, 14... Combiner, 12, 15... π/2 radian phase shifter, 16, 17... Phase synthesizer, 71, 72
...Detector, 73...Synthesizer, 74...
...BPF, 81,92...Phase difference discriminator, 82,93...LPFl9l...π
/4 radian phase shifter.

Claims (1)

[Claims] 1 As a device for detecting the position of a mobile object moving on a fixed travel path on the ground fixed side, a predetermined frequency f
The carrier wave of _0 has a frequency f_0/m (m is an integer of 2 or more)
equipment on the moving body side, consisting of a transmitter that generates an output modulated by a frequency-divided wave of 2 for every 3 bits of the address code based on the alternating binary code given to the section division points of the road divided into N sections.
N=2^(^3^/
^2^)^n (n is an even number) or N=2^(^3^/^
2^)^(^n^-^1^) x 2 (n is an odd number) n/2 sets or n parallel two-wire guide wire groups, each guide wire having an assigned address In accordance with the sign of the bit of the code, the interval between the two parallel lines is changed reciprocally to widen or narrow for each set of the above two lines at the interval dividing point, or they are crossed, and one end is connected to a resistor and the other end is connected to a coupler. It is equipped with a ground-fixed position detector that inputs the output of each guide wire obtained through the coupler and outputs the above address code, and the position detector has two terminals that are being input. Modulated wave extraction and voltage controlled oscillators that generate a reference phase signal of frequency f_0, which is frequency-synchronized by modulated wave (f_0/m) components extracted from the outputs of the two or more guiding wires, and two voltage controlled oscillators for each of the above three bits. A phase synthesis circuit is provided for each input from one set of guide wires and generates eight types of phase signals from the combined signal, and the eight types of phase signals are discriminated from the output of the phase synthesis circuit and the reference phase signal output. What is claimed is: 1. A position detection device for a moving body, comprising: a position detection circuit that outputs a code; and a code converter that generates an alternating binary code from the code output.