JPS5972242A - Data transmission system - Google Patents

Abstract

PURPOSE:To eliminate the need for a transmission line and to reduce the influence of noises by providing two opposite devices with optical transmitting means, receivers which receive part of a light signal and reflects the remainder to the opposite devices, and means which calculates the distance between the devices by using transmitted light and reflected light. CONSTITUTION:Distance measuring and data transmitting devices on a moving side 4 and a fixed side 4' are provided with projectors 5 and 5', photodetectors 6 and 6', distance measuring devices 7 and 7', and data transmitter and receivers 8 and 8'. The data transmitter and receivers 8 and 8' send out electric data signals ea and e'a to the projectors 5 and 5', which send out light data signals to the opposite-side photodetectors 6' and 6. The photodetectors 6' and 6 reflect part of the light data signals to the opposite-side photodetectors 6 and 6' and also receive and convert the remainders into electric data signals ea-2 and e'a-2. The distance measuring devices 7 and 7' generate electric signals eb and e'b for distance measurement and calculate the distance between both devices by using reflected signals eb-1 and e'b-1.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a data transmission system between two devices, at least one of which is movable and which are located opposite each other.

Conventionally, in data transmission between two devices, there is a method in which the two devices are connected via a transmission line such as a trolley wire, cabtire cable, or optical fiber, and data is transmitted by the transmission line. but.

Such a transmission system requires space for equipment to install the transmission line, increases costs, and requires maintenance. On the other hand, methods for transmitting data using radio waves have drawbacks such as interference with other wireless devices and the inability to achieve long transmission distances. However, the above data transmission methods cannot measure the distance between devices. For this purpose, there is a method of detecting the position of a moving object using, for example, a touch roller, but this method has the drawback of causing errors due to slipping, etc. Furthermore.

As described above, conventional data transmission and distance measurement between devices are performed using separate devices, which has the drawback of increasing the mounting space and increasing costs.

An object of the present invention is to provide a data transmission system that does not require a transmission line and is less affected by external noise.

Another object of the present invention is to provide a data transmission system that does not require separate special equipment for measuring distances between devices.

According to the invention, at least one is movable.

Each device provided facing each other includes an optical transmitting means for transmitting an optical signal including a data signal to the opposing device, and a light transmitting means for transmitting reflected light of the optical signal including the data signal reflected by the opposing device. Along with receiving.

an optical receiving means for receiving a part of an optical signal including a data signal transmitted from the opposing device and reflecting the remainder to the opposing device; A data transmission system is obtained which has a means for calculating the distance between the two points.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a front view showing the configuration when the present invention is applied to a mobile machine and a fixed station. The mobile machine 1 is opposed to the fixed station 2 via space, and moves in a direction toward or away from the fixed station 2. Two distance measurement and data transmission devices 4 used in the present invention are attached to a mounting base 3 installed on the mobile machine 1.

On the other hand, a distance measuring and data transmitting device 4' is also fixedly installed above the fixed stationary station 2. between these distance measurement and data transmission devices 4, 4'.

Optical signals including data signals are transmitted and received using space as a transmission medium.

FIG. 2 is a block diagram showing the configuration of one embodiment of the distance measurement/data transmission device of FIG. 1.

In the figure, reference numeral 4 indicates a distance measurement/data transmission device on the mobile machine side, and 4' indicates a distance measurement/data transmission device on the fixed station side.
and 4' are the light projecting devices 5 and 5', and the light receiving device 6, respectively.
and 6', distance measuring devices 7 and 7', and data transmitting/receiving devices 8 and 8'.

Next, the present invention will be explained in detail with reference to FIG.

The data transmitting/receiving device 8 (8') sends a data electric signal ea (ea') to the light projecting device 5 (5'). Light projector 5 (
5') receives the data electrical signal ea (ea') and sends the data optical signal ta (t,') to the other party's light receiving device 6' (6) through space.

Here, the data optical signal ta (ta') is transmitted to the light receiving device 6'.
The component za-1 (ta-, l') reflected by (6) and the component 7a that is not reflected and is received by the light receiving device 6' (6)
-2(ta-2') (not shown). That is.

The light receiving device 6' (6) receives the data optical signal ta (Aa'
) is reflected as reflected light ta-1 (za-i') to the other side light receiving device 6 (6'), and the remaining light ta-2 ( 4-
2') is received. The light receiving device 6' (6) converts the received light ta-, 2 (Aa-2') into a data electric signal (4-2
(ea-2') and data transmitting/receiving device 8' (8
).

On the other hand, the distance measuring device 7 (7') sends an electric signal eb (eb') for distance measurement (hereinafter abbreviated as distance measuring) to the projecting device 5 (5').
'), and the projector 5 (5') sends the ranging electric signal eb
(eb') to distance measuring optical signal 7b (tb') 1
．． -'C Send to the other party's light receiving device 6' (6). The light receiving device 6'(6') receives the reflected light tb of the ranging optical signal 1-b-(tb') reflected by the other party's light receiving device 6' (6).
-1 (tb-+') is received, and the reflected light tb-1 (tb-+') is received by the light receiving device 6 (6') as an electrical signal eb-1 (eb-1 (eb-+')).
-+') and sent to the distance measuring device 7 (7'). As a result, the distance measuring device 7 (7') receives the distance measuring electric signal eb (eb') and the reflected electric signal eb.
−+ (eb−+′) can be used to calculate the distance between devices.

In the configuration shown in FIG. 2, the light projecting device 5 (5') is
The distance measuring electric signal eb (eb
') and the data electric signal ea (e
It is necessary to multiplex the ranging optical signal tb(t
b') and data optical signal ta (ta') have the same optical wavelength, they are transmitted in a time-division manner.

Therefore, the optical signals tb (lb') and ta (ta'
) have different wavelengths, the other party's light receiving device 6' (6)
teeth.

Most of the optical signal tb (tb') is reflected using a corner cube, a photo sensor, etc., and the optical signal chi (la
') You can also receive most of them.

FIG. 3 is a block diagram showing a specific example of the data transmission method according to the present invention using the distance measurement/data transmission device shown in FIG. 2, taking into account the flow of signals.

In this example, data optical signals ta and ta' and ranging optical signals tb and tb' have the same optical wavelength, and these optical signals are transmitted and received in a time-division manner. Furthermore, this example employs a master-slave system. This mask slave method is
In this method, the slave device is switched between transmission mode and reception mode by a command from the master device, and data is exchanged between the master and slave devices. In this embodiment, the transmission mode consists of a data transmission mode and a ranging mode, and the reception mode consists of a data reception mode and a standby mode. In the figure, in order to make it easier to understand these modes, operating modes are shown with solid lines, and non-operating states are shown with dotted lines.

Here, the main device is a distance measuring and data transmitting device on the mobile machine side, and the slave device is a distance measuring and data transmitting device on the fixed station side.

Referring to FIG. 3(a), the main device and the slave device are indicated by 4 and 4', respectively, and the data transmitting/receiving device 8 (8') of each device has an input section 81 (81') and an output section 82. (8
2'). 9 (9') is a modulation/demodulation control unit that performs modulation/demodulation and switching control; here, the modulation unit 52 (
52') and demodulator 62 (62') are shown. Switching control is a control operation that decodes a predetermined command sent from the other device and sets the device to a predetermined mode, and also sends a predetermined command to the other device to set the device to the predetermined mode. and the switching control operation itself.

Since the control operation is similar to conventional control operations, it will not be described in detail here. 51 (51') is a floodlight, 61 (61')
indicates a light receiver, and the light emitter 5 (5') corresponding to Fig. 2
The device is composed of a light projector 61 (61') and a demodulator 62 (62'), which are composed of a projector 51 (51') and a modulator 52 (52'). 7 (7') is a distance measuring device as in the case of FIG.

FIG. 4 is a time chart for explaining the operation of FIG. 3. In Fig. 4, 1) shows the time chart of the distance measurement and data transmission device on the mobile machine side, which is the main device, and 2) shows the time chart of the distance measurement and data transmission device on the fixed station side, which is the slave device. ing. In each time chart, A is the data reception mode section,
B indicates a data transmission mode section, C indicates a ranging mode section, and D indicates a standby mode section. Needless to say, each of these modes is determined by the program of the main device 4 and the commands sent according to the program.

The operation of the data transmission system according to the present invention will be described below with reference to FIGS. 3(a) and 4. At time t1, the main device 4 is in data transmission mode B as shown in FIG.
Assume that the slave device 4' is in data reception mode A as shown in FIG.

At this time, the main device 4 receives the data electric signal e from the input section 81.
B is sent to the modulation section 52, and a modulated (for example, FM modulated) data electric signal is input to the light projector 51. Floodlight 51
transmits the modulated optical signal ta to the slave device 4'. In the slave device 4', a portion of the optical signal ta is reflected by the optical receiver 61' as an optical signal 1, 1, and the remainder is converted into a modulated data electrical signal. This modulated data electrical signal is demodulated by a demodulating section 62' and a data electrical signal ea-2 is outputted by an output section 8.
2'. The reflected optical signal 1,, is converted into an electrical signal modulated by the optical receiver 61 of the main device 4, and inputted to the demodulator 62. However, since the demodulator 62 is in an inactive state, the main device 4 does not receive electricity. No signal received.

When time t2 approaches, the main device 4 transmits a distance measurement execution command to the slave device 4'. At time t2, the main device 4 is set to distance measurement mode C by the modulation/demodulation control section 9 for a certain period of time (t6-t2) as shown in FIG. After decoding the distance execution command, the standby mode D is entered for a certain period of time (13-12) as shown in FIG. At this time.

As shown in FIG. 3(b), the main device 4 is a distance measuring device 7.
・From this distance measuring device 7, the distance measuring electric signal e%,
is transmitted to the modulator 52, and the modulated (for example, to a constant carrier frequency) electric distance measurement signal is input to the light projector 51.
1 converts this modulated ranging electrical signal into a ranging optical signal tb and transmits it to the slave device 4'.

In this state, the data transmitting/receiving device 8 of the main device 4 is disconnected from the modulation/demodulation control section 9. In the slave device 4', a part of the ranging optical signal Lb is reflected by the light receiver 61' as an optical signal Ab-+, and the rest is converted into a modulated electrical signal. This converted modulated electrical signal is given to the demodulator 62', but the demodulator 62' is in standby mode D and is inactive, so the slave device 4' does not receive the electrical signal. On the other hand, the optical signal tb-1 reflected by the optical receiver 61' is converted into an electrical signal modulated by the optical receiver 61 of the main device 4,
The signal is demodulated by the demodulator 62 and sent to the distance measuring device 7 as a distance measuring electric signal e b-4. The distance measuring device 7 measures the distance between the main device 4 and the slave device 4' using the transmitted distance measuring electric signal eb and the distance measuring electric signal eb-4 reflected and returned from the slave device 4'. . After completing the above operation between time t3 and t2, at time t3, the main device 4 returns to data transmission mode B as shown in FIG. The data reception mode A is entered as shown. Therefore, the operating state of each part of the main device 4 and the slave device 4' returns from the state shown in FIG. 3(b) to the state shown in FIG. 3(a).

As shown in the time chart in Figure 4 1), 2 hours and 11 tons
1 to time t4, the main device 4 is in transmission mode (B or C
), the slave device 4' is in reception mode.

The main device 4 is near the end of the transmission mode (B or C) (at time t).
4), the modem control section 9 transmits a data request command to the slave device 4' to enter the reception mode (A or D), and the slave device 4' decodes the data request command at the modem control section 9'. to enter the receiving mode (A or D). As a result, the main device 4 operates in the same manner as the receiving mode of the slave device 4' described above from time t4 to time t7, and the slave device 4'
operates in the same way as the transmission mode of the main device 4 described above.

During this period, the slave device 4' is operated for a certain period of time (t6-t
s) Immediately before time t5 to enter distance measurement mode, the modulation/demodulation control section 9' sends a distance measurement request data end command to the main device 4, and the main device 4 sends this distance measurement request data end command to the modulation/demodulation control section 9. for a certain period of time (t6 ts
), the mode becomes standby mode D, which is one of the reception modes. Then, near the end of the transmission mode (just before time t7), the slave device 4' sends a data end command from the modulation/demodulation control section 9' to the main device 4, and enters the reception mode. is decoded by the modulation/demodulation control section 9 to enter the transmission mode (B or C). In this way, the main device 4 and the slave device 4' exchange data while switching between the transmission mode and the reception mode, and measure the distance between the devices. At this time, the distance that can be measured is 10on~200m
It covers a wide range of areas.

As is clear from the above description, according to the present invention, not only can data be exchanged between devices, but also the distance between devices can be measured using reflected light. Furthermore, since it uses light, a data transmission system that is resistant to external noise can be obtained.

[Brief explanation of the drawing]

Figure 1 is a front view showing the configuration when the present invention is applied to a mobile machine and a fixed station, and Figure 2 is a front view showing the configuration of an embodiment of the distance measurement and data transmission device used in the present invention. 3(a) and 3(b) are block diagrams showing specific operational states of the data transmission system according to the present invention using the distance measuring data transmission device shown in FIG.
The figure is a time chart for explaining the operation of FIG. 3. Explanation of symbols 1: Mobile machine, 2: Fixed station, 3:
4 and 4' are the mounting base, 4 and 4' are the distance measuring and data transmission devices, 5 and 5' are the projecting devices, 6 and 6' are the light receiving devices, 7 and 7' are the distance measuring devices, and 8 and 8' are the data transmitting and receiving devices. , 9 , 9' are modulation/demodulation control units, 51 ,
51' is a floodlight, 52 and 52' are modulators, and 61
, 61' is a light receiver. 62, 62' are demodulating sections, 81, 8],' are input sections, and 82.degree. and 82' are output sections, respectively.

Claims (1)

[Scope of Claims] 1. Optical transmitting means, at least one of which is movable and is provided opposite to each other, for transmitting an optical signal including a data signal to the opposing device, and an optical transmitting means for transmitting an optical signal including a data signal to the opposing device, and a light transmitting means for transmitting an optical signal including a data signal to the opposing device, and a light transmitting means for transmitting an optical signal including a data signal to the opposing device; a part of the optical signal including the data signal transmitted from the opposing device; and a light that reflects the remainder to the opposing device. A distance between the device and the opposing device is determined using a receiving means, an optical signal including the data signal sent to the opposing device, and reflected light from which the optical signal is reflected by the opposing device. A data transmission method having a means for calculating. Remaining days below