JPH06318913A - Position detecting method for spatial transmission light communication equipment and mobile communication body - Google Patents

Abstract

PURPOSE:To enable not only the transmission/reception of communication data but also the position detection and navigation of a mobile communication body at a simplified equipment by enabling spatial transmission light communication without any law reguration by using a spatial transmission light communication equipment. CONSTITUTION:A photodetector 1 mounting a light receiving element 3 detects the direction of light from the light emitting element of a communication target according to received light intensity distribution while being rotated by an actuator 7 by using a rotary position detection sensor 2 fitted to the rotary part of the photodetector 1. On the other hand, an optical communication antenna 6 mounting a light emitting element 4 for data transmission and a light receiving element 5 for data reception can change the direction as well by using an actuator 8, information showing the direction of the other communication target provided by the photodetector 1 is fed back, and the transmission/ reception of data is performed while continuously matching the direction with that direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spatial transmission optical communication device capable of detecting the position of a mobile body while communicating data by spatial transmission optical communication in a communication system including the mobile body.

[0002]

2. Description of the Related Art Conventional communication transmission systems are roughly classified into three types. There are methods of laying electric wires and optical fibers, there are methods of radiating radio waves, and there is also a method of spatial communication using light.

[0003]

In the conventional communication transmission system having the above-mentioned structure, the following problems occur. Those laying electric wires and optical fibers and emitting radio waves are regulated by the Wired Telecommunications Law and Radio Law, respectively, and cannot be used freely personally.

Further, in radio communication, the risk of interference due to deterioration of the radio environment is increasing, and moreover, since the directivity of radio waves as a communication medium is low, it is possible to perform communication involving mobile objects, but on the other hand, Since it is very difficult to detect the position of a moving body using radio waves having such characteristics, when the moving body is included, the position detecting means and communication must be considered separately.

On the other hand, since spatial communication using light has a strong directivity, it is difficult to use it for communication including a mobile body, and it has drawbacks such as low reliability. Therefore, in the technology of spatial transmission optical communication that is not in practical use to date, the arrangement of light emitting parts is increased, the number of light emitting parts is increased, the area of light receiving parts is increased, and the optical system is devised. By doing so, we aim to reduce the influence of the directivity of the light and widen the reception range. An apparatus having a light emitting unit tracking function using this technique has also been proposed. With this device, only the direction of the moving body can be known.

These are disclosed in, for example, Japanese Patent Laid-Open No. 62-276932, Japanese Patent Laid-Open No. 1-120138, Japanese Patent Publication No. 2-57380 and the like. However, in these technologies, the focus is on simply solving the technical problem of how to reliably receive light so as not to interrupt communication.

There have also been considered methods for positively utilizing the directivity of light to detect the position of a moving body, etc. JP-A-4-315085, JP-A-2-57843 and JP-A-59 -6
As shown in Japanese Patent Publication No. 7476, etc., there is only the function of detecting the position by utilizing the directivity of light, and spatial transmission optical communication cannot be performed.

[0008] That is, by utilizing the directivity of light, it is considered to be applied to a short-distance communication system including a moving body which requires navigation as a technique for measuring the position and direction of the communicating body, together with a data transmission technique. However, at present, the apparatus and method for achieving this have not been established. In addition, in a conventional communication system including a mobile communication body, a complicated communication method and a complicated position detecting mechanism, a sensor, a circuit, etc. are required for the navigation.

[0009]

The present invention has been made to solve the above-mentioned technical problems, and a communication system in which a fixed communication body and at least one mobile communication body coexist and communicate with each other. In the space transmission optical communication device mounted on these communication bodies for use in the above, a detecting unit for detecting a light emitting direction from another fixed communication body or a mobile communication body that performs bidirectional communication, and the other fixed communication body. Alternatively, the space transmission light is provided with a communication unit for performing space transmission optical communication with a mobile communication body, and a control unit and a drive unit for making the communication unit follow the light receiving direction as the light emitting direction changes. It is a communication device.

In the position detecting method of the mobile communication unit, the position of the mobile communication unit is detected from the principle of triangulation by using the light emission direction from the other space transmission optical communication unit detected by the space transmission optical communication unit. Is a method for detecting the position of a mobile communication body.

[0011]

With the above-described structure, the space transmission optical communication device of the present invention enables space transmission optical communication in a communication system including a mobile body, and at the same time, a mobile communication body equipped with the present space transmission optical communication device. The position can be detected.

[0012]

1 shows a spatial transmission optical communication device according to a first embodiment of the present invention. The photodetector 1 equipped with the light receiving element 3 receives light from the light emitting element of the communication target according to the received light intensity distribution while rotating by the actuator 7, and searches for the direction of the communication target. And the direction is the photodetector 1
This can be known by the rotational position detection sensor 2 attached to the rotating part of the. On the other hand, an optical communication antenna 6 equipped with a light emitting element 4 for transmitting data and a light receiving element 5 for receiving data
The actuator 8 can also change the direction, and by feeding back information on the direction of another communication target obtained by the photodetector 1, the direction is continuously adjusted to that direction and data is transmitted and received. A flowchart showing the situation is shown in FIG.

Specifically, as shown in FIG. 3, the light received by the light receiving element 9 of the photodetector is amplified by the amplifier 10 and converted by the A / D converter 11 to check the intensity of the light. The light is input to the CPU 15 via the input side 14 of the I / O, and the received light is recognized. Then, even if the actuator 16 is driven by the driver 13 via the output side 24 of the I / O according to the instruction of the CPU 15 and the light of the light emitting element to be communicated moves, the light receiving element 9 of the photodetector is turned to the light direction. can do. The amount of change in orientation is recognized by the CPU 15 by the encoder 12 that is a rotational position detection sensor.

Next, in the optical communication antenna, the position information of the communication object fed back from the optical detector is sent to the CPU 1
5 and analyze it via the I / O output side 24
The actuator 25 is driven by 3 to align the direction with the optical communication antenna to be communicated. The amount of change in orientation is recognized by the CPU 15 by the encoder 22 that is a rotational position detection sensor. It should be noted that the CPU 15 monitors the directions of the photodetector and the optical communication antenna so that the amount of change is the same.

On the other hand, as described above, from the light emitting element 17 directed to the optical communication antenna of the other communication target, the transmission of the signal processed by the CPU 15 and amplified by the amplifier 18 via the output side 24 of the I / O. Signal light is emitted toward the other optical communication antenna and photodetector to be communicated. In addition, the light receiving element 19 for receiving from another communication object
The light received by is amplified by the amplifier 20, and the waveform shaping unit 21
Encoded by the CPU 15 via the input side 14 of the I / O
Entered in. Spatial transmission optical communication is performed by such a series of operations.

If only the light receiving element 5 of the optical communication antenna 6 can detect the light emitting direction of another communication target from the received light intensity and further the communication data can be received, the photodetector 1 becomes unnecessary. . Alternatively, while the light receiving element 5 of the optical communication antenna 6 is communicating, the photodetector 1 is rotated to search for the direction of the light from the light emitting element of the communication target that is not currently communicating. By searching for the direction of light from the light-emitting element of the communication target that is not currently communicating, the communication can be continued even if the communication that is currently being performed is interrupted.

FIGS. 4 and 5 show a second embodiment of the present invention, which is a first embodiment of the present invention, and which is a method for detecting the position of a mobile communication device equipped with the above-mentioned spatial transmission optical communication device. The communication system here may have a fixed communication body 26 and a mobile communication body 27 as shown in FIG. However, the total number of communicators shall be four or more. Each communication body is equipped with the above-mentioned space transmission optical communication device 27 and can communicate with each other. A two-dimensional coordinate system 29 is provided in this communication system, and the position of each communication body is shown in this coordinate system.

Here, the mobile communication unit 3 which is the object of position detection
0 must detect the communication directions 31a to 31f by the photodetector of the space transmission optical communication device 28 in order to transmit / receive data to / from other communication objects. FIG. 5 shows a case in which the directions of at least three other communication objects and the coordinates of the positions of the three communication objects are clear with respect to the mobile communication object 13 in this process. The position coordinates of each communication body are previously acquired by the fixed communication body 32/33 as map information for the fixed communication body 32/33, and the mobile communication body 34
Regarding the above, it is assumed that the mobile communication body 34 itself has acquired by communication with a fixed communication body or a mobile communication body other than that shown in FIG. Here, the communication direction of the mobile communication body 30 which is the object of position detection is 31g to 31i.

Then, the coordinate A of the fixed communication body 32 is set to (X ₁ ,
Y ₁ ), the coordinate B of the fixed communication body 33 is (X ₂ , Y ₂ ), the coordinate C of the mobile communication body 34 is (X ₃ , Y ₃ ), the mobile communication body 3
The coordinate D of 0 is (x, y), the distance between DB is L ₁ , the distance between AB is L ₂ , the distance between BC is L ₃ , and the distance between DA is L.
_4. Assuming that the angles are as shown in FIG. 5, the value of each variable in FIG. 5 is calculated from the following formula using the principle of triangulation from the coordinates A, coordinates B, coordinates C and θ ₁ and θ ₂ . Can be specifically obtained.

[0020]

[Equation 1]

[0021]

[Equation 2] Therefore, the coordinates D (x, y) of the mobile communication unit 13 can be obtained from these expressions as follows.

[0022]

[Equation 3] Here, the sign (positive or negative) of [Equation 3] changes depending on the positional relationship between the mobile communication body 30 and the fixed communication body 32, and the positional relationship is the map information previously acquired by the fixed communication body 32.
It is determined by the detection order of the fixed communication body 32 with respect to other communication bodies by the photodetector.

From the principle described above, the position of the mobile communication body 30 equipped with the spatial transmission optical communication device 28 can be calculated by communicating with the other three communication bodies and detecting their directions. Is possible. FIG. 6 shows a flowchart showing the state of this processing.

First, when it is necessary to immediately detect the position of the mobile communication unit 30, the mobile communication unit 30 and three or more other communication units are required.
Preferentially performs communication only for detecting the direction and position of the other communication body. Then, three communication bodies to be used for position detection are determined from among them, and the map information held by these communication bodies is received by communication to confirm the three positional relationships. Next, the positional relationship between the mobile communication unit 30 and the other three communication units described above is confirmed to confirm the mobile communication unit 30.
And θ ₁ and θ ₂ that occur between the other three communication objects described above are calculated. Finally, the position of the mobile communication body 30 is detected from the position data of the three communication bodies and θ ₁ and θ ₂ .

When it is not necessary to detect the position of the mobile communication unit 30, the mobile communication unit 30 and three or more other communication units perform normal communication including information such as control of speed and traveling direction, In the process, the position of the mobile communication body 30 is detected through the process described above.

The spatial transmission optical communication device having one optical detector and one optical communication antenna as shown in FIG. 1 has been described above. From now on, the optical detector and the optical communication antenna will be described. A spatial transmission optical communication device according to the third embodiment having two of each will be described. In this embodiment, the case where there are two optical communication antennas capable of detecting the light emitting direction of another communication target from the received light intensity will be described as an example, but the number of optical communication antennas is not limited to two, and a plurality of optical communication antennas may be provided. It is the essence. As will be described in advance, it is possible to detect the position of the communication object according to the above-mentioned principle even by using the spatial transmission optical communication device according to the third embodiment.

FIG. 7 shows a spatial transmission optical communication device according to a third embodiment of the present invention. Here, two light emitting elements 36a and 36b for transmitting data and a light receiving element 37 for receiving data are respectively provided.
Optical communication antennas 35a and 35b equipped with a and 37b
Receives the light from the light emitting element of the communication target according to the received light intensity distribution while rotating by the actuators 38a and 38b, and searches for the direction of the communication target. Then, the direction can be known by the angle detection sensors 39a and 39b attached to the optical communication antennas 35a and 35b. Then, by feeding back the information of the direction of the other communication target obtained by the light receiving elements 37a and 37b, the direction is continuously adjusted to the direction and the data is transmitted and received.

If the light receiving elements 37a and 37b of the optical communication antennas 35a and 35b alone cannot detect the light emitting direction of another communication target from the received light intensity, a plurality of photodetectors are required.

By using the spatial transmission optical communication device of the third embodiment, it is possible to surely perform communication even when performing communication while moving. Specifically, in the communication between the communication bodies equipped with the spatial transmission optical communication device of the first embodiment, the orientation of the optical communication antenna 6 is corrected so as not to interrupt the communication. If the following does not catch up or if there is an obstacle in the communication optical path, there is a disadvantage that the communication is temporarily interrupted.

In order to eliminate this inconvenience, fourth to sixth embodiments, which are communication methods using the third embodiment, can be considered. First, the fourth embodiment will be described in detail with reference to FIG. In the following embodiments, the reference numerals of the third embodiment will be used as they are for the optical communication antenna.

As shown in FIG. 8 (a), a fixed communication body 41 and a mobile communication body 4 equipped with the spatial transmission optical communication device of the third embodiment.
Consider a case in which the two communicate with each other using the optical communication antennas 35a and 35b, and the mobile communication body 42 is moving in the direction of arrow 43.

When the mobile communication body 42 moves in the direction of the arrow 43, an obstacle 44 exists between the fixed communication body 41 and the mobile communication body 42 as shown in FIG. 8B. Communication failure occurs temporarily.

In order to prevent such a situation, in this embodiment, when the fixed communication body 41 and the mobile communication body 42 are communicating with each other using the optical communication antenna 35a, FIG.
As shown in (c), the mobile communication body 42 has the optical communication antenna 3
If communication preparation for the other fixed communication body 45 is performed using 5b, it is possible to prevent the occurrence of the above-mentioned temporary communication failure, and it is possible to continue communication. In this embodiment, the optical communication antenna 35a and the optical communication antenna 35
The emission channel (frequency band) of b may be the same,
It can be different.

Here, it is assumed that the same communication content managed by a central management unit (not shown) is transmitted from the fixed communication units 41 and 45. Next, as a fifth embodiment, FIG.
As shown in (a), the fixed communication body 46 and the mobile communication body 4 each equipped with the spatial transmission optical communication device 40 of the third embodiment.
Consider a case where the mobile communication body 47 and the mobile communication body 7 communicate with each other using the optical communication antennas 35a and 35b, and the mobile communication body 47 is moving in the direction of the arrow 48.

When the mobile communication body 47 moves in the direction of the arrow 48, the optical communication antenna 35a of the mobile communication body 47 is moved by the movement of the mobile communication body 47 as shown in FIG. It may happen that the orientation of the optical communication antenna 35a of 46 does not match, and at that time, a communication failure occurs temporarily.

In order to prevent this, as shown in FIG. 9C, the fixed communication body 46 and the mobile communication body 47 respectively use the optical communication antenna 35b to perform communication in parallel with the communication by the optical communication antenna 35a. The optical communication antenna 3
The communication by 5a can be compensated. Therefore, it is possible to prevent the occurrence of the above-mentioned temporary communication failure, and it is possible to continue communication. In this embodiment, the light emitting channels (frequency bands) of the optical communication antenna 35a and the optical communication antenna 35b may be the same or different.

Further, as a sixth embodiment, as shown in FIG. 10, the fixed communication body 49 and the mobile communication body 51 and the mobile communication body 50, which mount the spatial transmission optical communication device of the third embodiment, communicate with each other. Therefore, consider a case where the mobile communication body 50 is moving in the direction of arrow 52 and the mobile communication body 51 is moving in the direction of arrow 53.

In this case, the optical communication antennas 35a and 35b of the spatial transmission optical communication device of the third embodiment can select a plurality of light emitting channels (frequency bands), and the optical communication antenna 35 can be selected.
Since a and 35b use different light emitting channels, one communication body (here, mobile communication body 50) simultaneously communicates with a plurality of communication bodies (here, fixed communication body 49 and mobile communication body 51). be able to.

That is, for example, the light emitting channel when the mobile communication body 50 communicates with the fixed communication body 49 using the optical communication antenna 35a, and the mobile communication body 50 communicates with the mobile communication body 51 using the optical communication antenna 35b. By changing the light emitting channel when performing the communication, the fixed communication body 49 and the mobile communication body 51 and the mobile communication body 50 can simultaneously communicate with each other.

By using such a communication method, a plurality of mobile communicators 50 and 51 are fixed communicators 49 serving as hosts.
Even when the work content from the mobile communication body 50 is communicated with the work content from the mobile communication body 50, the mobile communication bodies 50 and 51 can communicate with each other to avoid a collision and perform a predetermined work without collision.

If the device has a mechanism for detecting the direction of the communication object, it is possible to detect the position of the communication object according to the above-mentioned principle without using the space transmission optical communication devices 28 and 40 of the present invention.

Then, not only the transmission / reception of communication data and the position detection of the mobile communication unit, but only the position detection of the mobile communication unit is used for navigation of the mobile communication unit by light,
When other means such as radio is used for communication, the optical communication antenna becomes unnecessary, and the mobile communication body to be the position detection target may include only the photodetector. At this time, all the other communicators are fixed communicators and do not perform the spatial transmission optical communication but merely play a role of a lighthouse and thus have only a light emitting function.

However, since the communication target cannot be specified by the communication of the optical communication antenna in the mobile communication body which does not have such a space transmission optical communication function, the mobile communication body of the position detection target is specified only by the optical detector. Therefore, it is necessary to differentiate the fixed communication body by setting a different light emitting channel (frequency band) for each fixed communication body.

The position detection of all mobile communication objects described in the above embodiments is premised on the two-dimensional position detection, but the spatial light corresponding to the three-dimensional position detection is utilized by utilizing the position detection principle of the present invention. It is also possible to manufacture a transmission device.

As a method of using this spatial transmission optical communication device, specifically, navigation and speed control of an unmanned transfer robot in a factory, contact with a control center when an abnormality occurs, unmanned transfer robot It can be considered to be used for optimal placement.

[0046]

By using the space transmission optical communication device of the present invention, space transmission optical communication without legal restrictions is possible, and not only the transmission / reception of communication data but also the position detection of the mobile communication body can be performed by the simplified device. It is also possible to perform the navigation. At the same time, it becomes possible to communicate with a plurality of communicators, and even if there is an obstacle, reliable communication becomes possible.

[Brief description of drawings]

FIG. 1 is a perspective view of a spatial transmission optical communication device according to a first embodiment of the present invention.

FIG. 2 is a flowchart of a communication processing process according to the first embodiment of this invention.

FIG. 3 is a block diagram showing an outline of constituent parts of a first embodiment of the present invention.

FIG. 4 is a configuration diagram of a communication system assumed in a second embodiment of the present invention.

FIG. 5 is an explanatory diagram of a position detection principle of a communication system assumed in the second embodiment of the present invention.

FIG. 6 is a flow chart of a position detection process of a communication system assumed in the second embodiment of the present invention.

FIG. 7 is a perspective view of a spatial transmission optical communication device according to a third embodiment of the present invention.

FIG. 8 is a configuration diagram of a communication system assumed in a fourth embodiment of the present invention.

FIG. 9 is a configuration diagram of a communication system assumed in a fifth embodiment of the present invention.

FIG. 10 is a configuration diagram of a communication system assumed in a sixth embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Photodetector 2/12/22 ... Rotation position detection sensor (encoder) 3/5/9/19 / 37a / 37b ... Light receiving element 4/17 / 36a / 36b ... Light emitting element 6.35a / 35b ... Optical communication antenna 7/8/16/25 / 38a / 38b ... Actuator 10.18 / 20 ... Amplifier 11 ... A / D converter 12.13. 23 ... Driver 14 ... I / O input side 15 ... CPU 21 ... Waveform shaping section 24 ... I / O output side 26, 32, 33, 41, 45, 46, 49 ... Fixed communication body 27, 30, 34, 42, 47, 50, 51 ... Mobile communication body 28, 40 ... Spatial transmission optical communication Device 29 ... Two-dimensional coordinate axes of communication system 31a, 31b, 31c, 31d, 31e, 31f, 31g, 31h, 31
i ... communication direction 39a / 39b ... angle detection sensor 43.48.52.53 ... arrow 44 ... obstacle

Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location // G05D 1/02 P 9323-3H

Claims (5)

[Claims] 1. A communication system in which a fixed communication body and at least one mobile communication body coexist and are used for communication with each other,
In the space transmission optical communication device mounted on these communication bodies, a detecting unit for detecting a light emitting direction from another fixed communication body or a mobile communication body that performs bidirectional communication, and the other fixed communication body or the mobile communication body. A spatial transmission optical communication device comprising: a communication unit that performs spatial transmission optical communication with respect to the optical communication unit; and a control unit and a drive unit that cause the communication unit to follow the emission direction as the emission direction changes. 2. The spatial transmission optical communication device according to claim 1, comprising a plurality of detection units, communication units, and drive units. 3. The spatial transmission optical communication device according to claim 2, wherein the communication unit has a plurality of emission frequency bands. 4. The space transmission optical communication device according to claim 2, wherein the communication unit simultaneously performs a plurality of communications. 5. A method for detecting a position of a mobile communication body using the space transmission optical communication device according to claim 1, wherein the other space detected by the space transmission optical communication device is used. A method for detecting the position of a mobile communication body, characterized in that the position of the mobile communication body is obtained from the principle of triangulation using the light emission direction from the transmission optical communication device.