JPH083752B2 - Information transmission method by induction magnetic field - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for transmitting information to a moving body such as an automated guided vehicle, and in particular, to a magnetic field generated in a guide line laid along a moving path of the moving body. The present invention relates to an information transmission system using an induction magnetic field for transmitting various information such as position detection information.

[Prior Art] Detecting a magnetic field generated in the above-mentioned straight line portion by laying an induction line in which winding portions are arranged in a straight line portion at a set interval along a moving path of a moving body and applying an induced current to the guide line. Then, the deviation amount from the moving path of the moving body is detected, the traveling direction of the moving body is controlled so that the deviation amount becomes zero, and the magnetic field generated in the winding portion is detected. A movement control system for a moving body is known which detects the moving position of the moving body.

[Problems to be Solved by the Invention] In the above-described conventional movement control system, the information obtained at the winding portion of the guide line is only one type of information such as position detection information relatively indicating the moving position of the moving body. Therefore, it is impossible to transmit a plurality of information to the moving body, such as information indicating a right turn or a left turn when the moving body reaches the T-junction, or position detection information detecting the moving position by an absolute address. Met.

Therefore, it is an object of the present invention to obtain an information transmission method capable of transmitting a plurality of different information in a wound portion of an induction line.

[Means for Solving the Problems] In order to solve the above problems, the present invention provides a winding section provided on a guide line laid on the ground at a set interval with respect to the ground surface (moving surface of a moving body). It is composed of a horizontal winding part wound in the horizontal direction and a vertical winding part wound in the vertical direction, and it is possible to select either the horizontal winding part or the vertical winding part. By detecting the induced magnetic field generated from the horizontal winding portion or the vertical winding portion of the induction line by the magnetoelectric conversion element (magnetic field detecting means) provided in the moving body, the plurality of information different for the moving body can be detected. When there are many kinds of information to be transmitted, one horizontal winding section is composed of a plurality of horizontal winding sections and vertical winding sections, and the horizontal winding section of each group is formed. A code for assembling information is constructed by combining a winding part or a vertical winding part. Things.

[Embodiment] All of FIGS. 1 to 6 show the constitution of an embodiment of the present invention. FIG. 1 is a diagram showing an outline of the system constitution and installation of an induction line, and FIGS. The figure which shows the structure of the winding part,
FIG. 4 is a block diagram showing the main part of the signal processing system, and FIGS. 5 and 6 are diagrams for explaining the operation of the signal processing system.

 First, the outline of the system will be described with reference to FIG.

In the moving path B of the moving body A, a guide line L partially having a winding portion is embedded in the center of the floor surface thereof, and the guide line L is concerned.
An induced current generator T is connected to the.

The guide line L has a plurality of winding portions l ₁ provided at set intervals.
And the linear portion l ₂ which is laid in a straight line by connecting the plurality of winding portions l _{1 to} each other are formed in a so-called one-stroke form by one line.

In addition, the winding portions l ₁ are generally provided at equal intervals, but the intervals are not necessarily so, and the moving body A receives position detection information and the like in the traveling direction of the moving body A (hereinafter ,
It is called information detection. ) Is set appropriately depending on the points that require.

Further, the induced current generator T is for generating a sine wave signal current having a single frequency set within the range of several 100 Hz to several tens KHz as an induced signal.

The moving body A has a magnetic field detector for detecting information (hereinafter, referred to as a first magnetic field detector).
It is called a magnetic field detector. ) A, and a pair (two) of magnetic field detectors (hereinafter, referred to as a second magnetic field detector) b and c for detecting a shift in both sides of the moving body are provided, which will be described later with reference to FIG. A signal processing device is installed.

In the above-mentioned configuration, as will be specifically described later, the winding part l ₁ of the guide line L is composed of two winding parts which are orthogonal to each other, and the first magnetic field detector a of the moving body A has the above-mentioned two winding parts. The second magnetic field detector b, which is basically composed of two magnetoelectric conversion elements set in a direction sensitive to the magnetic field generated in the winding part,
The c is composed of a pair (two) of magnetoelectric conversion elements provided on both sides across the linear portion l ₂ in a direction sensitive to the magnetic field generated in the linear portion l ₂ of the induction line L. The setting directions of the first magnetic field detector a and the second magnetic field detectors b and c are orthogonal to each other because the directions of the magnetic fields received by them are orthogonal to each other.

Further, as the magnetoelectric conversion elements used as the first magnetic field detector a and the second magnetic field detectors b and c, there are an inductance having a detected magnetic field polarity, a Hall element, a magnetostrictive electric conversion element, and the like.

An embodiment of the present invention will be specifically described with reference to FIGS. 2 and 3. The embodiment shown in FIG. 2 and FIG. 3 is not limited to simply detecting the position in the traveling direction, but information specific to that point (for example, information indicating the turning point of the moving body A, information indicating the stopping point of the moving body A). Etc.) (the embodiment of FIG. 2), or the movement point can be indicated by an absolute address (the embodiment of FIG. 3). It should be noted that FIGS. 2 and 3 show only one or one of a plurality of windings corresponding to the winding portion l ₁ in FIG.

First, the embodiment shown in FIG. 2 will be described. The winding portion (l ₁ shown in FIG. ₁ ) of the guide line L includes linear portions orthogonal to the straight portion l _2, and is provided on the surface of the moving path B. On the other hand, it is composed of a vertical winding part l ₁₁ wound in the vertical direction and a horizontal winding part l ₁₂ wound in the horizontal direction with respect to the surface of the moving path B,
One of the two winding parts l ₁₁ and l ₁₂ is configured to be disconnected and connected to the straight part l ₂ by the switch S.
Is provided with _two first magnetic field detectors a ₁ and a _{2 which} are set in a direction in which the magnetic fields generated in the winding parts l ₁₁ and l ₁₂ are sensed.

Next, the embodiment shown in FIG. 3 will be described. The guide line L is wound with the same structure by the combination of the vertical winding portion l ₁₁ and the horizontal winding portion l ₁₂ of the embodiment shown in FIG. A plurality of units, for example, three units are configured as one set. (L ₁₁₁
And l ₁₂₁ , l ₁₁₂ and l ₁₂₂ , l ₁₁₃ and l ₁₂₃ ). Although not shown in FIG. 3, a switch S for switching between the two winding portions is attached to each of them, as in the embodiment of FIG. Further, the moving body A has three winding parts l ₁₁₁ and l ₁₂₁ , l _112.
And l ₁₂₂ , l ₁₁₃ and l ₁₂₃ respectively, the first magnetic field detectors a ₁₁ and a ₂₁ set in the same direction as the first magnetic field detectors a ₁ and a ₂ of the embodiment shown in FIG. , A ₁₂ and a ₂₂ and a ₁₃ and a ₂₃ are provided.

The structure for detecting the shift of the moving body A in both directions in the embodiment shown in FIGS. 2 and 3 is the same as the structure described in FIG.

In the above-described two embodiments, for example, a system in which the moving body A moves on a track laid on the moving path B or the like in which there is no fear of lateral deviation during movement, the deviation detection is performed. Configuration (second magnetic field detectors b, c, etc. of mobile unit A)
Does not need.

Further, in FIGS. 2 and 3, the winding part is represented by a rectangular shape with the number of windings being 1, but the number of windings may be two or more, and the shape of the winding is not necessarily rectangular. There is no.

Further, in the embodiment, as for the winding direction, one winding portion is horizontal and the other winding portion is vertical with respect to the moving surface of the moving body in the embodiment. You don't have to follow this.

Next, the configuration of the signal processing system will be described with reference to FIG.

The signal processing system includes a ground facility 1 provided for the moving path B and a mobile device 2 provided for the mobile A.

The ground equipment 1 is an induction current oscillator 11 composed of an oscillator that oscillates a sine wave signal current of a single frequency set within a range of several hundreds Hz to several tens KHz, and power-amplifies a signal from the induction current oscillator 11. It is composed of a power amplifier 12 and an induction line 13 through which an induction current from the power amplifier 12 flows. The combination of the induction current oscillator 11 and the power amplifier 12 is the induction current generator T shown in FIG. 1, and the induction line 13 is the induction line L formed by partially forming the winding portion l _1. Is.

The mobile device 2 includes a first magnetic field detector that detects a magnetic field generated in each winding portion (corresponding to the above l ₁₁ , l ₁₂ , l _{111 to} l ₁₂₃ ) of the winding portion l ₁ of the guide line 13. 21 (above a ₁ , a ₂ , a
Corresponds to _{11 to} a ₂₃ . ), The first magnetic field detector 21 detects a magnetic field to detect the output signal current, and outputs an envelope signal of the envelope detector 22, and compares the output signal of the envelope detector 22 with a reference level. Comparator 23 for outputting a signal component exceeding the reference level as an information detection signal of the moving body A, and the straight line portion l _{2 of the} guide line 13
Pair of second magnetic field detectors 24, 25 for detecting the magnetic field generated in the
(Corresponding to b and c above), the second magnetic field detectors 24 and 25 detect the magnetic field and detect the output signal current, and output a DC signal of a level proportional to the strength of the detection signal. Ultra linear detector (hereinafter referred to as Nilia detector) 2
6, 27, a subtracter 28 that performs level subtraction processing on the DC signals output from the linear detectors 26, 27 and outputs a shift detection signal in both directions of the moving body A. The first magnetic field detector 21 , The envelope detector 22 and the comparator 23 are the information detection signal processing system, the second magnetic field detectors 24 and 25, the linear detector 2
The system composed of 6,27 and the subtractor 28 constitutes a shift detection signal processing system.

In the embodiment shown in FIG. 2, the information detection signal processing system has one system for each of the vertical winding section l ₁₁ and the horizontal winding section l ₁₂ .
In the embodiment shown in FIG. 3, a total of two systems are vertical winding parts.
A total of 6 systems are provided, one for each of the l ₁₁₁ , l ₁₁₂ , l ₁₁₃ and the horizontal winding parts l ₁₂₁ , l ₁₂₂ , l ₁₂₃ .

In addition to the above, the mobile unit 2 includes a functional part for obtaining the information detection signal and the shift detection signal to control the traveling of the mobile unit A, for example. Since the task is to obtain the detection signal, the functional part is not shown and its description is omitted.

 First, the operation of the embodiment shown in FIG. 2 will be described.

An induced current is constantly flowing through the induced line L (13 in FIG. 4: hereinafter, the symbols in parentheses indicate the symbols in FIG. 4) by the induced current generator T (see FIG. 1). That is, as shown in FIG. 4, the induction current oscillator (11) constantly generates a sine wave signal by the oscillating action, and the sine wave signal is power-amplified by the power amplifier (12) and then the induction line L ( 1
3) is being applied.

In the embodiment shown in FIG. 2, as described above, in the ground facility (1), the induction line (13) wound portion is wound and in the horizontal direction vertical winding portion l ₁₁ wound in a vertical direction it in a horizontal winding portion l ₁₂ was turned, in the mobile apparatus (2), the first magnetic field detector (21) are provided corresponding to the each winding unit l _11, l ₁₂ ( First magnetic field detector a ₁ and a ₂ ).

The magnetic field Hv generated in the vertical winding portion l ₁₁ has a ring shape in the vertical direction, and the magnetic field Hh generated in the horizontal winding portion l ₁₂ has a ring shape in the horizontal direction. Therefore, when the magnetic field Hv is generated by setting the switch S to the 1 side as shown in the figure, the magnetic field Hv is sensed on the a ₁ side of the _two first magnetic field detectors a ₁ and a ₂ from the setting direction. , also is sensitive in two first magnetic field detector a _1, among a ₂ side of a ₂ of when the illustrated switch S in the 2 side which is opposite by which the above magnetic field Hh. As described above, in the embodiment shown in FIG. 2, two different pieces of information can be transmitted to the mobile unit A from the ground facility side.

This embodiment can be applied to, for example, temporary stop control of the moving body A on the moving path B, traveling direction control of the moving path B on the T-shaped road, and the like. That is, for example, the switch S is set to the 2 side at the temporary stop point, the switch S is set to the 1 side at other points, and when the first magnetic field detector a ₂ senses the magnetic field Hh, the moving body is moved. If the mobile device (2) is configured to stop A (that is, stop information is transmitted to the mobile A), stop control of the mobile A can be performed by a command from the ground facility (1). Become. Further, for example, in the T-shaped path of the moving path B, when the first magnetic field detector a ₁ side is sensitive to the magnetic field, for example, turn right, and when the first magnetic field detector a ₂ side is sensitive to the magnetic field, for example, turn left. by configuring the mobile device (2) to (i.e., the traveling direction instruction information is transmitted to mobile a.), 2 single winding provided in the T-junction unit l _11, l
_By the switching control of the ₁₂ switching switches S, the traveling direction of the moving body A can be controlled in the ground facility (1).

 Next, the operation of the embodiment shown in FIG. 3 will be described.

In the embodiment shown in FIG. 3, as described above, in the ground equipment (1), the winding portion of the guide line (13) has the configuration of the embodiment shown in FIG. Is provided,
(L ₁₁₁ and l ₁₂₁ , l ₁₂₁ and l ₁₂₂ , l ₁₁₃ and l ₁₂₃ ), and in the mobile device (2), the first magnetic field detector (21) has the winding parts l ₁₁₁ and l _{121 respectively.} , L ₁₁₂ , l ₁₂₂ , l ₁₁₃ , l ₁₂₃ (first magnetic field detectors a ₁₁ , a ₂₁ , a ₁₂ ,
a ₂₂ , a ₁₃ , a ₂₃ ).

Each winding part l _{111 which} is felt with the first magnetic field detectors a _{11 to} a ₂₃
The relationship of the magnetic fields from 1 to ₁₂₃ is the same as that of the embodiment shown in FIG. That is, it is as shown in Table 1 below.

Here, the first magnetic field detector a ₁₁ ~a ₂₃ sign is formed by whether sensitive to magnetic fields, for example, performs weighting to each as follows in Table 2.

However, in the above-mentioned Table 2, it is assumed that the code formation is "0" without magnetic field sensitivity and "1" with magnetic field sensitivity.

The relationship between the combination of the first magnetic field detectors a _{11 to} a _{23 that} senses a magnetic field and outputs a signal according to the weight in Table 2 above and the number (quantization number) represented by the combination is as follows.
It looks like the table.

One example of the contents shown in Table 3 is that, for example, the switch S (see FIG. 2; hereinafter the same applies to the switch S) of the pair of winding parts l ₁₁₁ and l ₁₂₁ is switched to the 1 side and the vertical winding is performed. The part l ₁₁₁ generates a magnetic field Hv (see FIG. 2, the same applies to the following magnetic fields Hv and Hh), and the switch S of the pair of the winding parts l ₁₁₂ and l ₁₂₂ is switched to the 2 side, and the horizontal winding is performed. Part l ₁₂₂ is magnetic field
Hh has occurred a further winding portion l ₁₁₃ and l ₁₂₃ set of switches S 1 vertical winding portion have been switched to the side l ₁₁₃ magnetic field Hv
Is generated, the first magnetic field detector to be sensed is a ₁₁ , a
₂₂ and a ₁₃ , and the information (quantization number) expressed in this case is “2” (a ₁₁ + a ₂₂ + a ₁₃ = (0 ×
1) + (1 × 2) + (0 × 4) = 2).

According to the above configuration, eight kinds of information can be expressed by the combination of the first magnetic field detectors a _{11 to} a ₂₃ that are sensitive to the magnetic field, and thereby more complicated control regarding the traveling of the moving body A can be performed. This is possible from the ground facility (1) side, and the configuration shown in FIG. 3 makes it possible to detect points at absolute addresses (8 absolute addresses in the case of FIG. 3). When increasing the absolute address number, the guide line L
In the mobile device (2), the number of combinations of horizontal and vertical winding parts included in one set is increased, and the information detection signal processing system (in FIG. 4, "21", "22" and "2") is included.
It suffices to provide as many 3 "systems as the first magnetic field detectors (21) (twice the number of combinations of winding parts).

The signal processing operation after detecting the magnetic field by the first magnetic field detectors a ₁ , a ₂ , a _{11 to} a ₂₃ (21) in the two embodiments described above will be described with reference to FIG.

Since the first magnetic field detector (21) of the moving body A is sensitive to the alternating magnetic field Hh or Hv generated in the winding part l ₁ from the setting direction, the moving body A follows the moving path B, 1 magnetic field detector (2
The first magnetic field detector (21) each time 1) crosses the winding part l _1.
Outputs a signal as shown in FIG. 5 e _1. This signal is input to the envelope detector (22) and detected.
It becomes the envelope signal shown in e ₂ , and this envelope signal e ₂ is input to the comparator (23) and compared with the reference level, and the portion exceeding this is output as a rectangular wave signal as shown in FIG. 5 e ₃ . Then, this rectangular wave signal e ₃ becomes an information detection signal.

The information detection signal e ₃ is supplied to the winding parts l ₁₁ , l ₁₂ , l _{111 to} l ₁₂₃ shown in FIG. 2 or 3 by switching the switch S.
It will be obtained separately from each other.

Further, the operation for detecting the deviation amount in the traveling both directions of the moving body A, that is, the signal processing operation for detecting the magnetic field Hs generated in the straight line portion l ₂ of the guide line L to obtain the deviation amount. Will be described with reference to FIG. 6 and FIG.

The second magnetic field detectors b (24) and c (25) are sensitive to the alternating magnetic field Hs generated in the linear portion l ₂ from the setting direction thereof, and the second magnetic field detectors b (24) and c (25) are detected. 25) each generate a signal whose strength is proportional to the distance from the straight line portion l ₂ (distance in the lateral direction of the moving body A), and this signal is generated by the linear detector (2
6) and (27) are detected respectively, and the detection signal (DC signal) of the level corresponding to the strength of each signal is obtained.

These two detection signals are subtracted by the subtractor (28),
The shift detection signal e ₄ is obtained.

Explaining the shift detection signal e ₄ , the level-to-movement distance characteristic of the shift detection signal obtained by the subtraction processing of the two detection signals exhibits an S-shaped characteristic as shown in FIG. Good linearity is exhibited within a certain range (± d). Here, for example, if the level of the shift detection signal e ₄ is Va, the moving body A moves in a straight line of the guide line L at an equal distance from its lateral center position (equal distance from the pair of second magnetic field detectors b and c). Position where part l ₂ exists: It means that it is displaced to the right by d ₁ from the origin 0) shown in FIG. Here, if the position of the moving body A in the traveling side is controlled so that the level V of the shift detection signal is always zero, the moving body A moves in the laying direction of the guide line L (along the center of the moving path B). ) It will proceed correctly.

It should be noted that the above-described shift amount detection processing is not necessary for a moving body that is not likely to shift laterally during movement, as described above.

EFFECTS OF THE INVENTION As described above, according to the present invention, a winding portion including two winding portions that are orthogonal to each other is provided in the moving path of the moving body at a set interval, and two winding portions are provided for each winding portion. A magnetic field for information transmission is generated by selecting either one of the parts, and this is detected by the moving body, and it is possible to increase the types of information transmitted from the ground equipment to the moving body. Therefore, the control of the moving body from the ground equipment can be diversified, and the moving point of the moving body can be detected by the absolute address.

[Brief description of drawings]

Each of the drawings is a diagram for explaining an embodiment of the present invention. FIG. 1 is a system configuration diagram, FIGS. 2 and 3 are configuration diagrams of a winding section, and FIG. 4 is a block diagram showing a signal processing system. 5 and 6 are explanatory diagrams of the operation of the signal processing system. (Main symbols) L ...... induction lines _{l 1, l 11, l 12} , l 111 ~l 123 ...... winding portion l ₂ ...... straight portion T ...... induced current generator A ...... mobile, S ... … Switches a, a ₁ , a ₂ , a _{11 to} a ₂₃ …… First magnetic field detector b, c …… Second magnetic field detector 1 …… Ground equipment, 11 …… Induction current oscillator 13 …… Induction line 2 ...... Mobile device 21 …… First magnetic field detector 24,25 …… Second magnetic field detector.

Claims (4)

[Claims] 1. A plurality of winding portions formed by a combination of two winding portions that include linear portions that are orthogonal to each other and orthogonal to the moving direction of a moving body, are arranged at predetermined intervals along the moving path. Connect them in series and arrange them, and repeat the above 2 for each winding part.
One of the two winding portions can be selected, and a magnetic field generated in the selected winding portion is differentiated from each other in the moving portion by causing an induced current to flow through the winding portion. An information transmission method using an induction magnetic field, which is adapted to transmit a plurality of different pieces of information to the moving body by detecting the information. 2. A code for assembling information by combining a plurality of sets of two winding parts which are orthogonal to each other in series to form one winding part and by selectively combining the winding parts in each set. An information transmission system using an induction magnetic field according to claim 1, wherein 3. The two winding parts constituting the winding part, one of which is wound in a horizontal direction with respect to a moving surface of the moving body and the other of which is wound in a vertical direction, respectively. An information transmission system using an induction magnetic field according to the second item. 4. A guide line laid along a moving path of the moving body to control a traveling direction of the moving body is wound at set intervals so as to include a linear portion in a direction orthogonal to the guide line. An information transmission system using an induction magnetic field according to any one of claims 1 to 3, wherein the winding portion is formed by turning.