JPH0951309A - Inter vehicle communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely transmit information that a specified vehicle has to the other vehicle even if a road becomes congested and the multiple vehicles form a line in a travel direction or when the distance between the vehicles in a freeway is considerably long and when the transmissvity of air between the vehicles is deteriorated due to rain and fog. SOLUTION: A front light projecting/receiving part 10 receiving or emitting a laser light signal from/to the front part of the vehicle and a rear light projecting/receiving part 20 receiving or emitting the laser light signal from or to the rear part of the vehicle are provided. A signal relaying means 30 relaying a signal between the front light projecting/receiving part 10 and the rear light projecting/receiving part 20 so that the laser light signal including the signal received by the front light projecting/receiving part 10 is emitted from the rear light projecting/receiving part 20 and the laser light signal including the signal received by the rear light projecting/receiving part 20 is emitted from the front light-projecting/receiving part 10 is provided. Thus, the successive transmission of the signal among vehicles is realized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle-to-vehicle communication system, and more particularly to an extremely high vehicle-to-vehicle distance even when a road is congested and a large number of vehicles form a line in the traveling direction. Even if it is very long or the air permeability between vehicles is deteriorated due to rain or fog, the information that a particular vehicle has is reliably transmitted to other vehicles, and the safety of the vehicle and automatic control The present invention relates to an inter-vehicle communication system that can contribute to smoothing and the like.

[0002]

2. Description of the Related Art Generally, the information obtained by a driver of a vehicle by his or her five senses is quite limited. Especially when the road is congested and there are other vehicles in front and behind, the visibility in front of and behind the vehicle becomes unclear. As for the road surface condition, etc., usually only the surroundings of the own vehicle can be discriminated, and the warning sound emitted by the emergency vehicle can hardly be heard when the window is closed and the radio is rang. This is also the case when various sensors are attached to the vehicle, and there is a limit to detecting the situation in front of or far behind the vehicle in advance, especially when traffic is congested or when driving at high speed. Accidents and troubles often occur due to lack of information.
Therefore, a vehicle-to-vehicle communication system for exchanging information by wireless communication between vehicles has been put into practical use. Conventionally, as this vehicle-to-vehicle communication system, a device simply using infrared rays or radio waves has been studied or put into practical use. However, there is no system capable of forwarding signals among a plurality of vehicles.

[0003]

Therefore, the conventional inter-vehicle communication system has the following problems. (A) In the case of using infrared rays, signal transmission is interrupted by an adjacent vehicle, so that communication with a vehicle further ahead or behind the adjacent vehicle is hardly possible. (B) In addition, if infrared rays are used, the communication distance cannot be sufficiently set (up to about 50 m), and if the vehicle-to-vehicle distance is long, such as when traveling at high speed, communication with the vehicle immediately before or immediately after is not possible. Is likely to become. Further, since it is easy to be attenuated by mere infrared rays, when the air permeability between the vehicles is deteriorated due to rain, fog, etc., the communicable distance is reduced, which is a practical problem. (C) On the other hand, the one using radio waves has a problem that it is highly possible that signals from an unspecified number of vehicles are received, and it is not possible to obtain necessary information by limiting the vehicles.

Therefore, the present invention provides, for example, when the road is congested and a large number of vehicles form a line in the traveling direction, or when the inter-vehicle distance is very long on a highway or the like, or when the inter-vehicle air permeability is high. Even if it is getting worse due to rain or fog,
It is an object of the present invention to provide a vehicle-to-vehicle communication system in which information held by a specific vehicle is surely transmitted to other vehicles, which contributes to vehicle safety and smooth automatic vehicle control.

[0005]

In order to achieve the above object, a vehicle-to-vehicle communication system according to a first aspect of the present invention includes a front light emitting / receiving unit for receiving or transmitting an optical signal to the front of the vehicle, and a rear light transmitting / receiving unit to the rear of the vehicle. A rear light projecting / receiving section for receiving or transmitting an optical signal, and an optical signal including a signal received by the rear projecting / receiving section while transmitting an optical signal including the signal received by the front projecting / receiving section from the rear projecting / receiving section So as to be transmitted from the front light emitting / receiving unit, and signal relay means for relaying a signal between the front light emitting / receiving unit and the rear light emitting / receiving unit. The vehicle-to-vehicle communication system according to claim 2 is characterized in that a laser light signal is used as the light signal.

An inter-vehicle communication system according to a third aspect of the invention is characterized in that an optical fiber is used as a signal transmission line constituting the signal relay means.

A vehicle-to-vehicle communication system according to a fourth aspect of the present invention comprises a situation detecting means for detecting a situation of a vehicle or the vicinity of the vehicle,
Optical signal generating means for converting the information indicating the situation detected by the situation detecting means into an optical signal transmitted from the front light emitting / receiving portion or the rear light emitting / receiving portion and outputting the optical signal.

A vehicle-to-vehicle communication system according to a fifth aspect of the present invention comprises a reading means for reading an optical signal transmitted through the signal relay means,
It is characterized in that it is provided with an informing unit for informing the driver or the passenger of the vehicle of the information read by the reading unit.

According to a sixth aspect of the vehicle-to-vehicle communication system, a reading means for reading an optical signal transmitted through the signal relay means,
And a control means for controlling the operation of the vehicle based on the information read by the reading means.

According to a seventh aspect of the vehicle-to-vehicle communication system, input means for a driver or a passenger of the vehicle to input information, and the information input by the input means is transmitted to the front light emitting / receiving section or the rear side. An optical signal generating means for converting into an optical signal transmitted from the light emitting / receiving unit and outputting the optical signal is provided.

The vehicle-to-vehicle communication system according to claim 8 is characterized in that it is provided with a signal adding means for adding the information transmitted through one vehicle to the signal transmitted through the signal relay means.

[0012]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram schematically showing a vehicle to which the vehicle-to-vehicle communication system of the present invention is applied. FIG.
FIG. 3 is a plan view showing a state where these vehicles are transmitting and receiving signals to and from each other. In FIG. 2, the solid line shows the laser light signal transmitted backward, and the half line shows the laser light signal transmitted forward. The front part of the vehicle 1 is provided with a front light projecting / receiving part 10 which receives or transmits a laser light signal to the front of the vehicle, and the rear part of the vehicle 1 receives or transmits a laser light signal to the rear of the vehicle. A rear light projecting / receiving unit 20 is provided. The optical fibers 31, 32, 33, 3 are provided between the front light emitting / receiving unit 10 and the rear light emitting / receiving unit 20.
Signal relay means 30 including 4, 35 is provided. In this example, the wavelength division multiplexing method is used as a multiplexing method for transmitting two laser light signals (a backward signal and a forward signal) with a series of optical fibers.

The front light projecting / receiving unit 10 includes an optical multiplexer / demultiplexer 11
And a light receiving unit 12 and a light projecting unit 13 connected to the optical multiplexer / demultiplexer 11 by an optical fiber. The optical multiplexer / demultiplexer 11 causes a laser beam having a first specific wavelength of the light incident from the front of the vehicle 1 to enter the optical fiber 31, and on the other hand, a second specific light that has propagated forward in the optical fiber 31. The laser light of a wavelength is demultiplexed and taken out. Light receiving part 1
Reference numeral 2 denotes an optical lens or the like that collects light incident from the front of the vehicle 1 as needed and guides it to the optical multiplexer / demultiplexer 11. The light projecting unit 13 demultiplexes the light by the optical multiplexer / demultiplexer 11. It is composed of an optical lens or the like that emits the generated second laser light of a specific wavelength in front of the vehicle at an appropriate emission angle. Similarly, the rear light projecting / receiving unit 20 includes an optical multiplexer / demultiplexer 21 and a light receiving unit 2 connected to the optical multiplexer / demultiplexer 21 by an optical fiber.
2 and the light projecting unit 23. The optical multiplexer / demultiplexer 21 causes the laser light of the second specific wavelength, out of the light incident from the rear of the vehicle 1, to enter the optical fiber 33, while the first specific light that has propagated backward in the optical fiber 33. The laser light of a wavelength is demultiplexed and taken out. The light receiving section 22 is composed of an optical lens or the like that collects the light incident from the rear of the vehicle 1 as necessary and guides it to the optical multiplexer / demultiplexer 21, and the light projecting section 2
Reference numeral 3 denotes an optical lens or the like that emits the laser light of the first specific wavelength, which is demultiplexed by the optical multiplexer / demultiplexer 21, to the rear of the vehicle at an appropriate emission angle. Here, as the optical multiplexer / demultiplexers 11 and 21, those using a prism, those using an interference film filter, or those using a diffraction grating can be used. Further, the light projecting units 13 and 23 do not necessarily need to be provided with optical lenses as long as they can emit laser light at an appropriate radiation angle 2θ as shown in FIG. For example, if the light receiving angle (numerical aperture) of the optical fiber to be used is sufficiently large, the laser beam of the second specific wavelength demultiplexed by the optical demultiplexer 11 or the optical demultiplexer 21 demultiplexes. The end face of the optical fiber that guides the laser light of the first specific wavelength may be desired as it is in front of or behind the vehicle.

The signal relay means 30 comprises optical fibers 31, 3
2, 33, 34, 35, optical switches 36, 37, optical multiplexer / demultiplexers 38, 39, electro-optical converters 41, 42,
It is composed of photoelectric converters 43 and 44 and a communication control circuit 50. The optical fibers 31, 32, 33, 34, 35 are, for example, multimode step index optical fibers, and in this case, the number of cores is one. The optical fiber 31 has one end connected to the optical multiplexer / demultiplexer 11 and the other end connected to the optical fiber 34 or the optical fiber 32 via the optical switch 36. The optical fiber 32 has one end connected to the optical fiber 31 via an optical switch 36 and the other end connected to an optical fiber 33 via an optical switch 37. The optical fiber 33 is
One end is connected to the optical multiplexer / demultiplexer 21, and the other end is connected to the optical fiber 35 or the optical fiber 32 via the optical switch 37. As the optical switches 36 and 37, for example, a mechanical type using a movable fiber or a mechanical type using a movable prism can be used. Also, the optical switch 3
In this case, 6 and 37 are controlled and switched by the communication control circuit 50, and unless the control signal is input, the optical fibers 31, 32 and 33 are maintained in a state of being sequentially connected.

The optical multiplexer / demultiplexer 38 applies the laser light of the second specific wavelength output from the electro-optical converter 41 to the optical fiber 3
4 is made incident, and on the other hand, the laser beam of the first specific wavelength propagating backward in the optical fiber 34 is demultiplexed and taken out. The optical multiplexer / demultiplexer 39 causes the laser light of the first specific wavelength output from the electro-optical converter 42 to be incident on the optical fiber 35, while the second laser light propagating in the optical fiber 35 in the forward direction. The laser light of a specific wavelength is demultiplexed and taken out. The electro-optical converters 41 and 42 are, for example, laser diodes, driven by the communication control circuit 50, and have different wavelengths (second specific wavelength or first wavelength).
Laser light of a specific wavelength). Also,
The photoelectric converters 43 and 44 are, for example, photodiodes, and the communication control circuit 50 uses the laser light signal demultiplexed by the optical multiplexer / demultiplexer 38 or the optical multiplexer / demultiplexer 39 as an electrical signal.
Is what you enter. Here, the electro-optical converter 4
1, 42 constitute the optical signal generating means of the present invention together with the communication control circuit 50.

The communication control circuit 50 is a drive circuit for the electro-optical converters 41 and 42 for generating a laser light signal, an amplification / shaping circuit for reading signals input by the opto-electric converters 43 and 44, and various types. The reading circuit, the optical signal generating circuit, and the control circuit of the present invention are constituted by an electric circuit including a processing circuit (for example, a microcomputer) for performing processing calculation. In this case, a notification unit 61, a status detection unit 62, and an input unit 63 are provided as devices connected to the communication control circuit 50 by an electric wire or the like. The communication control circuit 50 firstly switches, for example, the optical switches 36 and 37 at regular time intervals for a short time so that the optical fibers 31,
The laser light signal incident on and propagating to 33 is periodically read, and the read result is notified to the driver or passenger of the vehicle by the notification means 61, and based on the read result, each system (brake system etc.) of the vehicle is notified. It has the function of sending signals and controlling the vehicle. The communication control circuit 50
At this time, based on whether the information input from the opto-electric converter 43 or the information input from the opto-electric converter 44, the information to be notified is obtained from the rear of the vehicle or from the front of the vehicle. It is determined whether the obtained result is obtained, the result of the determination is utilized for the control of the vehicle, and the result of the determination is also notified.

Here, the information to be superimposed on the laser light signal is, for example, (a) that the vehicle ahead is suddenly decelerated,
(B) There are stopped vehicles, obstacles, etc. on the road ahead or in the vicinity, (c) The road surface in front or near is a bad road (snow road, frozen road, etc.), (d) Front Or, the weather around is bad (rain, fog, etc.), (e) there is large unevenness on the road surface in front or near, (f) that an emergency vehicle (ambulance, etc.) is approaching from the front or the rear, ( g) There is a tunnel or a sharp curve ahead, and (h) there is contact information between specific vehicles. The notification means 61 includes, for example, a display (specifically, a CRT, a liquid crystal display, a warning lamp, etc.) and a sound (speaker, etc.).
Further, in controlling the vehicle based on the reading result by the communication control circuit 50, for example, in the cases of the above (a) to (f), a command is sent to the brake system or the engine control system to forcibly control the own vehicle. Control processing for decelerating and maintaining low speed running, control processing for forcibly turning on the headlights and fog lights of the host vehicle in the cases of (d) and (g) above, and active suspension control system in the case of above (e) There may be a process that sends data indicating the presence or the degree of unevenness and enables more rapid and accurate suspension control such as control based on the preview sensor.

Secondly, the communication control circuit 50 receives an input signal from the situation detecting means 62 or the input means 63,
The electro-optical converters 41 and 42 are driven to generate a laser light signal on which the information represented by these input signals is superimposed, and the optical switch 36 or 37 is switched for a certain period of time to forward this laser light signal. Or rear light emitting / receiving section 2
It has the function of transmitting from 0 to the front or rear of the vehicle.
In the case shown in FIG. 1, the situation detecting means 62 is a sensor for detecting the road surface situation under the front part of the host vehicle, and specifically, a distance measuring sensor for detecting the road surface height and a road surface state (snow). A CCD camera or the like for determining a road, a frozen road, etc. In addition to this, as the situation detecting means of the present invention,
A distance-measuring sensor that measures the distance to the immediately preceding vehicle, a CCD camera that captures the surrounding situation, or a sensor that detects the operating status of the vehicle (acceleration, deceleration, stop, engine stop, brake abnormality, etc.) possible. The circuit (for example, an image processing circuit) that processes the signal from the status detection unit 62 may be provided inside the communication control circuit 50 or may be provided separately. The input means 63 is composed of, for example, a switch or a keyboard, a voice microphone, or the like, and the driver or passenger of the vehicle communication-controls a signal indicating the surrounding conditions such as (a) to (g) described above and contact information. It can be input to the circuit 50.

Thirdly, the communication control circuit 50 also has a function of amplifying a signal between the front light emitting / receiving unit 10 and the rear light emitting / receiving unit 20. That is, in the above-described reading operation, when it is determined that the intensity of the laser light signal that has entered the optical fibers 31 and 33 is lower than a value sufficient for spatial transmission, the optical switches 36 and 37. The optical fibers 31 and 33 are switched to the optical fibers 34 and 35.
Functioning as a relay amplifier that holds the state of being always connected to, and amplifies the signals input by the opto-electric converters 43 and 44 in this state, and outputs the signals as they are via the electro-optical converters 41 and 42, respectively. .

A vehicle to which the vehicle-to-vehicle communication system having the configuration described above is applied, for example, even when a road is congested and a large number of vehicles form a line in the traveling direction, and the vehicle-to-vehicle distance is very high on a highway or the like. Even if it is long or the air permeability between vehicles is deteriorated due to rain or fog, the information that a particular vehicle has can be reliably transmitted to other vehicles, and the safety of the vehicle and automatic vehicle control can be improved. It can contribute to facilitation. That is, the information detected by the situation detection means 62 of a specific vehicle and the information input by the driver of a specific vehicle are transferred to the front light emitting / receiving unit 10 or the rear by the above-described function of the communication control circuit 50 of the vehicle. The light is emitted from the light emitting / receiving unit 20 to the front or the rear as a laser light signal of sufficient strength. As is well known, laser light can realize much higher intensity, directivity, etc. than mere infrared rays, etc., so even when the distance between the vehicle where the signal is transmitted and the vehicles in front of and behind it is extremely long,
Even if the transmission characteristics in the atmosphere are poor, this laser light signal is surely received by the front light emitting / receiving unit 10 or the rear light emitting / receiving unit 20 of the front and rear vehicles and the communication control circuit 50 of the vehicle.
Is read. Then, this laser light signal is amplified as it is via the received optical fibers 31, 32, 33 of the vehicle, or is amplified by the function of the communication control circuit 50 described above when the intensity is lowered, The signal is transmitted to the side opposite to the side received from the light emitting / receiving unit (that is, the forward signal is forward as it is and the backward signal is backward as it is), and is sequentially transmitted to the vehicle in front or rear.

For this reason, the situation detecting means 62 of the specific vehicle
The information detected by the driver or the information input by the driver of a specific vehicle is blocked by the laser light signal emitted from the specific vehicle and is almost unreachable further forward or backward. Vehicle, and the vehicle in front of or in the rear of the vehicle. Therefore, it becomes possible to perform vehicle-to-vehicle communication that is far wider and more reliable than before, and for example, there are the following specific advantages. (1) When a specific vehicle is suddenly braked and suddenly decelerated while a large number of vehicles are running in a line, this situation is detected by the specific vehicle itself or a vehicle running immediately behind. Then, since the detection information can be forwarded to and transmitted to a vehicle further behind, the driver of the vehicle behind, which cannot see the specific vehicle due to the view of the vehicle on the way, is also notified by the notification means 61. By knowing the situation, it becomes possible to drive quickly and accurately, such as slowing down the speed in advance, and it is possible to reduce collisions and the like. Further, in this case, the brake system can be automatically controlled to reduce the speed in advance irrespective of the driver's operation, and a safer and more accurate auto cruise operation can be performed.

(2) If the road is a bad road such as a snowy road or an icy road, there are stopped vehicles or obstacles on the road, if there are large irregularities on the road, the weather in front or near When it is raining or fog, or when there is a tunnel ahead, this situation can be detected by a specific vehicle approaching in the vicinity and the detection information can be forwarded to the vehicles behind. Therefore, the driver of the vehicle behind, who cannot see this situation because the vehicle on the way is obstructing the field of vision or the distance is long, also knows this situation by the notification means 61 and slows down in advance. In addition, quick and appropriate operation such as turning on the headlights and fog lights can be performed, and slip accidents can be significantly reduced. In this case, a command is sent to the brake system, active suspension system, headlamps, etc. to reduce the speed in advance regardless of the driver's operation, suspension control such as control based on the preview sensor, headlamps, etc. Can be turned on automatically, which makes safer and more comfortable auto cruise driving possible. (3) When an emergency vehicle approaches, it can be detected by a specific vehicle in the vicinity of the emergency vehicle, and the detection information can be forwarded to further forward or rearward vehicles and transmitted.
This situation cannot be seen because the vehicle on the way is obstructing the field of view or the distance is too far away. The driver of the vehicle behind or in front of the vehicle, or the vehicle that cannot hear the warning sound of the emergency vehicle because the window is closed This situation can be surely notified to the driver of the vehicle by the notification means 61, and swift and accurate measures such as due to the shoulder of the road can be promptly performed, and the emergency vehicle competing for the moment cannot run smoothly or stops. Trouble can be reduced. In this case, the communication system is also applied to the emergency vehicle itself so that the emergency personnel of the emergency vehicle can input the information including the instruction of the approach of the emergency vehicle and the approach to the road shoulder from the input means 63, and the emergency vehicle itself. Therefore, a laser light signal on which this information is superimposed may be transmitted. In this way, even if the emergency vehicle does not approach any of the vehicles, the presence of the emergency vehicle can be notified to many vehicles that are traveling on the same road quickly and reliably, so that the emergency vehicle can run smoothly. It can certainly be achieved.

(4) Further, for example, a laser light signal (having a first specific wavelength in the case of this example) having information such as "there is a sharp curve ahead" and "there is a tunnel ahead" is run. If the laser light signal transmitting means for irradiating the front of the vehicle is installed on the road shoulder, etc. slightly in front of the place where there is a sharp curve, a specific vehicle will actually approach the place where there is a sharp curve. Even without it, it is possible to contribute to the prevention of vehicle accidents by notifying this information to a large number of vehicles traveling on the same road early and surely and realizing early brake operation and automatic brake control. (5) Further, for example, if this system is applied to a plurality of vehicles used for escorting important persons, etc.,
There is an effect that information can be exchanged reliably and in a wide range between the leading vehicle (vehicle on which an important person is boarding) and the vehicle that escorts the rear, and smooth escort can be performed. Further, in this case, only the laser light signal directed forward from the front vehicle and the laser light signal directed rearward from the vehicle at the rear end are set not to be emitted, and preferably the wavelength of the laser light signal or the superposition of signals is superimposed. If you set the method (modulation method) to a specific one that can not be used by the general public, ordinary vehicles or third parties on the ground will receive and read this information,
Since it becomes almost impossible as compared with the case of using radio waves, there is also an effect that contact information such as a course change when escorting an important person is surely prevented from being leaked to a third party.

In the example of the above embodiment, the front light projecting / receiving unit and the rear light projecting / receiving unit are relayed by using the optical fiber, but the signal relaying means of the present invention is not limited to this. For example, if the front light projecting / receiving unit and the rear light projecting / receiving unit are provided with the electro-optical converting unit and the opto-electric converting unit, the signal relaying unit may be composed of only an electric wire or an electric circuit connecting them. However, as is well known, when transmitting the same amount of information, an optical fiber is much thinner and lighter than an electric wire, which contributes to weight reduction and space saving. Further, as the optical signal of the present invention, mere infrared rays, visible rays or the like may be used instead of laser light. Even in this case, by sending signals among a large number of vehicles in sequence, it is possible to perform vehicle-to-vehicle communication with a wider range and more reliable than in the past. However, with laser light, higher output and higher directivity can be realized, so that there is an effect such that the communicable state can be maintained even when the inter-vehicle distance becomes extremely long. In this case, for example, an LED (light emitting diode) may be used as the electro-optical converter. Further, the multiplexing method for transmitting the backward signal and the forward signal through the series of transmission lines is not limited to the wavelength division multiplexing method as in the above example. For example, as in a second example shown in FIG. 3 described later, a space division multiplex system in which the number of cores of an optical fiber or the like is two may be used. In this case, each optical multiplexer / demultiplexer becomes unnecessary. Further, as in a second example shown in FIG. 3 described later, a communication control circuit is always interposed between the front light emitting / receiving unit 10 and the rear light emitting / receiving unit 20 to perform signal relay, amplification, processing, and the like. You may In this case, the optical switches 36 and 37, the optical fiber 32, etc. are unnecessary. Further, the communication control circuit 50 as the signal reading means or the optical signal generating means, the situation detecting means, or the input means is not always essential. For example, there may be a system in which these elements are mounted only in a specific vehicle such as a police car or an ambulance, and in a general vehicle only a front light emitting / receiving unit, a rear light emitting / receiving unit, and a signal relay unit are mounted. In this case, for example, police cars who are in a row of traffic jams and are distant from each other can use a general vehicle on the way as a relay device to reliably and extensively obtain business information and be intercepted by a third party. You can exchange information without having to.

Next, a second example of the embodiment of the present invention will be described with reference to the drawings. The same components as those in the above-described embodiment shown in FIGS. 1 and 2 are designated by the same reference numerals and the description thereof will be omitted. FIG. 3 is a diagram schematically showing a vehicle to which another embodiment (second example) of the inter-vehicle communication system of the present invention is applied. The front part of the vehicle 1 is provided with a front light projecting / receiving part 10a for receiving or transmitting a laser light signal to the front of the vehicle, and the rear part of the vehicle 1 receiving or transmitting a laser light signal to the rear of the vehicle. A rear light projecting / receiving unit 20a is provided. Then, the front light projecting / receiving unit 10a and the rear light projecting / receiving unit 20a.
Between the optical fibers 31a, 31b, 33a, 33
A signal relay means 30a including b is provided. In this example, the space division multiplexing method is used as a multiplexing method for transmitting two laser light signals (a backward signal and a forward signal) with a series of optical fibers.

The front light projecting / receiving section 10a includes an optical fiber 31.
The light receiving unit 12 and the light projecting unit 13 are respectively connected to a and 31b. Similarly, the rear light projecting / receiving unit 20a is
The light receiving unit 22 and the light projecting unit 23 are respectively connected to the optical fibers 33b and 33a. Signal relay means 30a
Are optical fibers 31a, 31b, 33a, 33b, electro-optical converters 41, 42, opto-electric converters 43, 44, and
It is composed of a communication control circuit 50a. Optical fibers 31a, 3
Reference numerals 1b, 33a, and 33b are, for example, multimode step index optical fibers, and in this case, constitute an optical fiber cable having two cores as a whole. Optical fiber 31
One end of a is connected to the light receiving unit 12, and the other end is connected to the photoelectric converter 43. The optical fiber 31b has one end connected to the light projecting unit 13 and the other end connected to the electro-optical converter 41. One end of the optical fiber 33a is connected to the light projecting section 23, and the other end is connected to the electro-optical converter 42.
One end of the optical fiber 33b is connected to the light receiving section 22, and the other end is connected to the photoelectric converter 44. Here,
The electro-optical converters 41 and 42, together with the communication control circuit 50a, constitute the optical signal generating means of the present invention.

The communication control circuit 50a is a drive circuit for the electro-optical converters 41 and 42 for generating a laser light signal, an amplification / shaping circuit for reading the signals input by the opto-electric converters 43 and 44, and a signal. The reading circuit, the optical signal generating circuit, the control circuit, and the signal adding circuit of the present invention are configured by an electric circuit including a processing circuit (for example, a microcomputer) that performs the processing and various processing calculations. in this case,
A notification unit 61, a status detection unit 62, and an input unit 63 are provided as devices connected to the communication control circuit 50a by an electric wire or the like. The communication control circuit 50a has a first
In addition, it has a function of relaying a signal between the front light projecting / receiving unit 10a and the rear light projecting / receiving unit 20a. That is, the optical fiber 31
a, 33b are incident on and propagated, and photoelectric converters 43, 44
It functions as a repeater that amplifies a signal input via the optical amplifier and outputs it as it is via the electro-optical converters 41 and 42, respectively. At this time, the communication control circuit 5
0a adds the information of passing one vehicle to the information to be relayed. Specifically, for example, a process of increasing the information (numerical value) indicating the number of vehicles passing through in the relayed laser light signal by one is performed.

Secondly, the communication control circuit 50a periodically reads the laser light signal which is incident on the optical fibers 31a and 33b, propagates, and is inputted through the photoelectric converters 43 and 44. The notifying means 61 has a function of notifying the driver or passenger of the vehicle and controlling the vehicle based on the read result. At this time, the communication control circuit 50a determines whether the information is obtained from the rear of the vehicle based on the information input from the photoelectric converter 43 or the information input from the photoelectric converter 44, or It is determined whether or not it is obtained from the front of the vehicle, this is utilized for the control of the vehicle, and the determination result is also reported. In addition, at this time, by reading the information indicating the number of vehicles passing through, it is also determined how many vehicles from the previous vehicle or how many vehicles the vehicle is coming from, and this is used for the control of the vehicle. Will be notified at the same time. Thirdly, the communication control circuit 50a receives the input signal from the situation detecting means 62 or the input means 63, drives the electro-optical converters 41 and 42, and superimposes the information represented by these input signals. It has a function of generating a signal and transmitting this laser light signal to the front or the rear of the vehicle from the front light projecting / receiving unit 10a or the rear light projecting / receiving unit 20a. At this time, the above-mentioned information indicating the number of passing vehicles is initially set to 1 and transmitted.

Also in the vehicle to which the vehicle-to-vehicle communication system having the above-described configuration is applied, as in the case of the above-described first example, for example, when a road is congested and a large number of vehicles form a line in the traveling direction, In addition, even if the distance between vehicles is very long on a highway, etc., or even if the atmospheric permeability between vehicles is deteriorated by rain, fog, etc., the information that each vehicle has is reliably transmitted to other vehicles, It can contribute to vehicle safety, automation of driving, and sophistication. Moreover, in this case, the transmitted / received laser light signal includes information (numerical value) indicating the number of passing vehicles, and when the signal is relayed in the communication control circuit 50a, one piece of information indicating the passing number is provided. Will be increased. Then, when the communication control circuit 50a reads the laser light signal, it is also determined based on this information how many vehicles have come from the vehicle or how many vehicles have come from this vehicle, and this is utilized for vehicle control. At the same time, this determination result is also notified at the same time. Therefore, in the case of this example, in addition to the advantages (1) to (5) described above, for example, the following advantages are specifically provided. (6) When there is a vehicle-to-vehicle communication informing of the presence of a vehicle that has suddenly braked in the front and suddenly decelerated, or when the road ahead is a bad road such as a snowy road or an icy road Even when notified by communication, or when an emergency vehicle approaches, etc., if the vehicle or place is located too far in advance, notification or automatic control of the braking system (forced braking) is performed. Can be no
Too quickly to avoid unnecessary notification or vehicle control,
More precise and comfortable vehicle driving operations and automatic cruise driving are possible. (7) Further, in communication between vehicles such as police cars traveling on the same road, it is convenient to know the position of each other vehicle (how many vehicles are behind or how many vehicles).

[0030]

According to the first aspect of the present invention, information can be surely and widely transmitted even when, for example, a road is congested and a large number of vehicles form a line in the traveling direction.
That is, in the case of a vehicle to which the vehicle-to-vehicle communication system is applied, information transmitted as an optical signal from the front or the rear of the vehicle is received by one of the front light projecting / receiving unit and the rear light projecting / receiving unit, and is transmitted by the signal relay unit. The signal is relayed and retransmitted as an optical signal containing the information from the other of the front light emitting / receiving unit or the rear light emitting / receiving unit. For this reason, this optical signal is surely forwarded and transmitted from the particular vehicle that has been transmitted to the vehicle ahead or behind in order. Therefore, the vehicle-to-vehicle communication that is far wider and more reliable than before can be performed. Particularly, according to the second aspect of the invention, a laser light signal is used as the light signal. As is well known, laser light can realize much higher intensity and directivity than infrared light, so even when the distance between the vehicle from which the signal is transmitted and the vehicles in front of and behind it is extremely long Even if the transmission characteristic inside is extremely poor, it is surely received by the front light emitting / receiving unit or the rear light emitting / receiving unit of the vehicle in the front or the rear, the above-mentioned signal forwarding is made more sure, and the communication reliability is further improved. To do.

According to the third aspect of the present invention, since the optical fiber is used as the signal transmission line constituting the signal relaying means, it is possible to realize space saving and weight reduction as compared with the case of using the electric wire.

According to the invention described in claim 4, the situation of the vehicle or the surroundings of the vehicle is detected by the situation detecting means, and the information indicating this situation is transmitted from the front light emitting / receiving section or the rear light emitting / receiving section by the optical signal generating means. The converted optical signal is output. For this reason, a specific vehicle automatically becomes a source of information about the surrounding situation without the driver's operation, and this information can be reliably used as a relay device for many other vehicles traveling on the same road. It can be transmitted over long distances.

According to the fifth aspect of the invention, the reading means reads the optical signal transmitted through the signal relay means, and the notifying means notifies the driver or passenger of the vehicle of the read information.
Therefore, the information transmitted from a specific vehicle or the like can be transmitted to the drivers and the like of many other vehicles traveling on the same road, which can contribute to the prevention of vehicle accidents and troubles. For example, it is safe to notify the driver of the vehicle behind by sudden deceleration of the vehicle ahead, the presence of obstacles on the road ahead, the fact that the road ahead is a bad road, etc. It becomes possible to drive. It is also possible to notify the driver of a vehicle at a long distance of the approach of the emergency vehicle in an early and sure manner, and quickly approach the road shoulder to ensure the smooth passage of the emergency vehicle.

According to the sixth aspect of the present invention, the reading means reads the optical signal transmitted through the signal relay means, and the control means controls the operation of the vehicle based on the read information. Therefore, smooth vehicle control can be realized by utilizing the information transmitted from a specific vehicle or the like to control a large number of other vehicles traveling on the same road. For example, based on information such as the sudden deceleration of the vehicle ahead, the presence of obstacles on the road ahead, the fact that the road ahead is a bad road, etc., the brake system of the vehicle behind can be activated early to automatically decelerate in advance. It enables safe and smooth auto cruise control. Further, by inputting information such as unevenness on the road surface in the front into the active suspension system of the vehicle in the rear early, it is possible to realize more comfortable and comfortable running.

According to the invention described in claim 7, the information inputted by the driver or the passenger of the vehicle by the input means is converted into the optical signal by the optical signal generating means, and the information is transmitted from the front light emitting / receiving portion or the rear light emitting / receiving portion. Sent. Therefore, the information sensed by the driver or the like can be reliably transmitted to a long distance by using a large number of other vehicles traveling on the same road as relay devices.
Therefore, for example, it is possible to contribute to the reliable communication of information between vehicles such as police cars and convoys that travel apart on the same road.

According to the invention described in claim 8, the information passing through one vehicle is added to the signal transmitted through the signal relaying means by the signal adding means. Therefore, from the transmitted optical signal, it is possible to identify from which vehicle in front or behind the information (excluding the added information) is transmitted, and more useful information can be utilized. It will be possible. For example, if there is a vehicle-to-vehicle communication informing of the presence of a vehicle that has suddenly braked in the front and suddenly decelerated, or if the road ahead is a bad road such as a snowy road or an icy road If the vehicle or place is located too far in front of the emergency vehicle, even if the vehicle is informed that the emergency vehicle is approaching, no notification or automatic control of the braking system (forced braking) is performed. Therefore, there is an effect that it is possible to avoid unnecessary notification or vehicle control too quickly and to perform more accurate and comfortable vehicle driving operation, auto cruise driving, and the like.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an inter-vehicle communication system that is an example of an embodiment of the present invention.

FIG. 2 is a plan view showing a signal transmission / reception state between vehicles to which the vehicle-to-vehicle communication system according to the exemplary embodiment of the present invention is applied.

FIG. 3 is a block diagram showing a configuration of an inter-vehicle communication system which is another example of the embodiment of the present invention.

[Explanation of symbols]

1 Vehicle 10, 10a Front light emitting / receiving unit 20, 20a Rear light emitting / receiving unit 31, 32, 33, 34, 35 Optical fiber (signal transmission line) 31a, 31b, 33a, 33b Optical fiber (signal transmission line) 50, 50a Communication Control circuit (signal relaying means, optical signal generating means, control means, signal adding means) 61 notification means 62 status detection means 63 input means

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁶ Identification number Internal reference number FI Technical indication H04B 10/22 (72) Inventor Yoshifumi Kawabata 10 Oenron, Hanazonocho, Ukyo-ku, Kyoto Within the corporation

Claims (8)

[Claims] 1. A front light emitting / receiving unit for receiving or transmitting an optical signal to the front of the vehicle, a rear light emitting / receiving unit for receiving or transmitting an optical signal to the rear of the vehicle, and a signal received by the front light emitting / receiving unit. Is transmitted from the rear light-emitter / receiver and the light signal including the signal received by the rear light-emitter / receiver is transmitted from the front light-emitter / receiver. And a signal relay means for relaying signals between the parts. 2. The inter-vehicle communication system according to claim 1, wherein a laser optical signal is used as the optical signal. 3. The vehicle-to-vehicle communication system according to claim 1, wherein an optical fiber is used as a signal transmission path which constitutes the signal relay means. 4. A situation detecting means for detecting a situation of a vehicle or the vicinity of the vehicle, and information indicating the situation detected by the situation detecting means in an optical signal transmitted from the front light emitting / receiving portion or the rear light emitting / receiving portion. 4. An inter-vehicle communication system according to claim 1, further comprising an optical signal generating means for converting and outputting. 5. A reading means for reading an optical signal transmitted through the signal relay means, and an informing means for informing a driver or a passenger of the vehicle of the information read by the reading means. 5. The inter-vehicle communication system according to any one of 4 to 4. 6. The reading means for reading an optical signal transmitted through the signal relay means, and the control means for controlling the operation of the vehicle based on the information read by the reading means. 6. The inter-vehicle communication system according to any one of 1 to 5. 7. An input means for a driver or an occupant of a vehicle to input information, and an optical signal transmitted from the front light projecting / receiving section or the rear light projecting / receiving section for the information input by the input means. The inter-vehicle communication system according to any one of claims 1 to 6, further comprising: an optical signal generating unit that converts and outputs the optical signal. 8. The vehicle 1 according to the signal transmitted through the signal relay means.
The vehicle-to-vehicle communication system according to any one of claims 1 to 7, further comprising a signal adding means for adding information that has passed through the table.