JPH09293194A - Communication system between vehicles - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inter-vehicle communication system, which controls travel while transmission/reception are frequently executed between a guide vehicle and following vehicles. SOLUTION: In the inter-vehicle communication system in which the guiding vehicle A and the plural following vehicles B1 travel in a line, the guiding vehicle A transmits information to the following vehicles B1 at every prescribed period and the respective following vehicles B1 return information to the front vehicle when they receive information from the front vehicle and transmits information from the front vehicle to the following vehicles B1 . At the time of returning information to the front vehicle next time, return information from the subsequent following vehicles B1 is returned, and the self vehicle is recognized as the last following vehicle when there is no return from the subsequent following vehicles B1 and returns information to the front vehicle. Thus, information is efficiently transmitted to the respective following vehicles from the guiding vehicle A as a synchronous source. The guiding vehicle recognizes that information is normally transmitted to the last vehicle.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication system between vehicles in which a leading vehicle and a plurality of following vehicles travel in a row, and in particular, a leading vehicle operated by a driver guides on a predetermined road (track, road). However, the present invention relates to a communication system between vehicles that guides a plurality of following vehicles.

[0002]

2. Description of the Related Art A vehicle group traveling system in which a leading vehicle and a plurality of following vehicles travel in a row (convoy traveling) has been conventionally studied in order to improve the efficiency of luggage and personnel transportation.

In this type of system, in order to ensure safe operation, it is necessary for the following vehicle to travel in accordance with the traveling state of the leading vehicle while maintaining an appropriate inter-vehicle distance between the front and rear vehicles. is there.

An example of such a vehicle group traveling system (this system is a premise technique of the present invention and is not known,
Naturally, this part also has novelty. 2) and FIG.
2 is an image outline diagram of this system, in which a beacon D for notifying the latitude and longitude received from a satellite E is erected at a predetermined interval on the shoulder of a premises road C such as a factory, and the premises The vehicle group traveling on the road C includes a leading vehicle A operated by a driver while grasping position information based on a signal from the beacon D, and an unmanned following vehicle B ₁ following the leading vehicle A _1.
The unmanned follower vehicle B ₁ ...

FIG. 3 is a block diagram of an automatic tracking system as a communication system of such a vehicle group traveling system, in which A is a leading vehicle and B ₁ and B ₂ are following vehicles (following vehicles). The leading vehicle A has an external environment sensor 11 for grasping a road surface condition, a steering wheel 13a operated by a driver 12, an engine 13b,
Each vehicle traveling state of the T / M 13c, the brake 13d, etc. is grasped on the basis of a sensor (not shown), and the sensor vehicle information is converted into a radio signal, which is transmitted to the following vehicle group via the in-vehicle communication device 15, The sensor vehicle information and the traveling information obtained from the beacon D or the like are transmitted to the adjacent one succeeding vehicle via the front-rear communication device 16.

A road-to-vehicle communication device 17 exchanges signals such as vehicle position information and road position information by transmitting and receiving between the beacons D. An emergency information communication device 18 receives emergency information 19 from the outside and operates an emergency stop switch 20 to perform an emergency stop. On the other hand, in the following vehicle (following vehicle B ₁ ...), unlike the leading vehicle A, front-rear communication devices 16 are provided on the front side and the rear side of the vehicle, respectively, and the control ECU is used instead of the driver 12.
24 is mounted, and based on the signal from the communication ECU 14, the steering 13a, the engine 13b, the T / M1
3c, the brake 13d, etc. are automatically controlled.

Reference numeral 23 denotes a relative position sensor provided on the front side of the vehicle. The reflector 22 provided on the rear surface side of the front vehicle reflects light, and the reflected light is received by the relative position sensor 23 to detect an inter-vehicle distance between adjacent vehicles. EC and control the signal
Guide to U24 and set the engine 1 so that the specified vehicle distance is achieved.
3b, T / M 13c, brake 13d, etc. are controlled.

In such a communication system, a vehicle in which one or a plurality of unmanned follower vehicles B ₁ ... are led to a leading vehicle A operated by a driver while exchanging traveling information between front vehicle information and rear vehicle information. There is no conventional communication method between them. However, a technique disclosed in Japanese Patent Laid-Open No. 241100/1992 is disclosed as a driving support device for preventing a rear-end collision of a plurality of vehicles traveling on a normal road.

Such a technique detects the running state of the vehicle,
Transmitting means for transmitting the detected traveling state as traveling data of the own vehicle, receiving means for receiving traveling data of the other vehicle transmitted from another vehicle, and traveling data received by the receiving means. Based on the traveling data of the other vehicle directly received by the receiving means, and the traveling data of the further vehicle received through the relaying means of the other vehicle, It proposes a technique provided with a command means for issuing an operation command to the own vehicle.

According to the present invention, not only other vehicles but also the traveling states of other vehicles can be detected through the relay means, so that the driving assistance such as the rear-end collision prevention is performed based on these traveling states. Is.

[0011]

However, the above-mentioned technique measures the distance between the vehicles operated by the driver independently of each other to prevent the rear-end collision, as shown in FIGS. 2 and 3 of the present invention. A plurality of following vehicles B ₁ ... are not led to follow the leading vehicle A operated by another driver.

Therefore, in the invention according to claim 2 of the prior art, there is provided a measuring means for measuring an inter-vehicle distance to a preceding vehicle, a transmitting means for transmitting inter-vehicle distance data acquired by the measuring means, and Receiving means for receiving inter-vehicle distance data between the other vehicle and a vehicle in front of the other vehicle transmitted from the vehicle, inter-vehicle distance data measured by the measuring means,
And command means for issuing an operation command to the vehicle of the own vehicle based on the inter-vehicle distance data received by the receiving means,
Based on the inter-vehicle distance data, the operation command means grasps the running condition of the vehicle, and when the inter-vehicle distance is close and there is a possibility of a rear-end collision, a brake operation or a deceleration command is issued to the own vehicle. It is configured to issue a command. Therefore, the communication method in the prior art does not need to acquire travel information between adjacent vehicles as frequently as in the present invention,
For this reason, the above-mentioned conventional technology performs indiscriminate transmission / reception without synchronizing signal reception.

Therefore, the present invention cannot be applied to the communication system of the device which frequently transmits and receives between the leading vehicle A and the following vehicle B ₁ ... Therefore, the present invention is directed to a leading vehicle A and a following vehicle B.
It is to provide an inter-vehicle communication method that can be effectively applied to a system that controls traveling while frequently transmitting and receiving between ₁ ... Another object of the present invention is to provide an inter-vehicle communication system capable of setting an effective transmission / reception interval by following the speed fluctuation of the leading vehicle A.

[0014]

According to the first aspect of the present invention,
In a communication method between vehicles in which a leading vehicle and a plurality of following vehicles travel in a row, the leading vehicle transmits to a following vehicle immediately after every predetermined period, and each following vehicle receives information from an adjacent preceding vehicle. Then, the reply from the preceding vehicle is transmitted, the information from the preceding vehicle is transmitted to an adjacent succeeding vehicle, and the previous reply information from the succeeding vehicle is returned when replying to the preceding vehicle.

According to this invention, the following vehicle, when receiving information from the preceding vehicle, sends a reply to the preceding vehicle and a transmission to the following vehicle. Since this reply and transmission are performed by each following vehicle, the information from the leading vehicle is sequentially transmitted to each following vehicle, but the reply information from each following vehicle is transmitted only to the immediately preceding vehicle. However, when each following vehicle replies to the preceding vehicle, it returns the previous reply information from the following vehicle, so that the immediately preceding vehicle is 2
It is possible to receive the reply information of one cycle before from the vehicle behind the vehicle (the vehicle following the vehicle following the vehicle). That is, the reply information returned to the vehicle ahead is transmitted to the vehicle further ahead in the next cycle, and reaches the leading vehicle by repeating the control cycle. In this way, since information is sequentially transmitted to each following vehicle using the leading vehicle as a synchronization source, transmission and reception do not interfere with each other. It is possible to confirm that the information has been normally transmitted, and it is possible to realize a communication system that is particularly useful, reliable, and efficient when three or more vehicles run in a row.

According to the second aspect of the invention, the leading vehicle transmits the vehicle data to the immediately following vehicle, and each of the following vehicles transmits the preceding vehicle data and the vehicle data when transmitting to the following vehicle. When sending a reply to the preceding vehicle, the host vehicle data and the following vehicle data obtained by the previous reply from the following vehicle are transmitted. As a result, each vehicle can accurately grasp the state of the other vehicle, and it becomes possible to efficiently lead the vehicle and improve the safety.

The third aspect of the present invention is characterized in that the following vehicle responds to the preceding vehicle by recognizing the own vehicle as the last vehicle when there is no response from the following vehicle.
According to this invention, it is possible to automatically recognize the tail car depending on whether or not there is a reply from the following car, and it is not necessary to set a special tail car recognition means on the tail car, and the tail car to the front car is not required. Car recognition information can also be transmitted.

According to a fourth aspect of the present invention, the leading vehicle is driven by a driver, and the following vehicles are automatically driven based on information obtained from the leading vehicle directly or via the forward following vehicle. Characterize. According to such an invention, only the leading vehicle can be manned and the following vehicle can be unmanned, which enables platooning with reduced labor and improves transportation efficiency.

According to a fifth aspect of the present invention, the leading vehicle sets the predetermined cycle to be shorter as the vehicle speed increases. According to this invention, the transmission / reception cycle of communication is shortened as the vehicle speed increases, the situation change of each vehicle can be grasped quickly and accurately at high speed, and the accuracy of lead driving can be improved, and the load of signal processing at low speed is increased. It will be reduced.

The invention according to claim 6 is characterized in that the communication between the adjacent vehicles is performed by using a light wave or a millimeter wave as a communication medium. In particular, the present invention requires reliable transmission and reception only between adjacent vehicles, and therefore, when a medium such as a radio wave that causes diffraction is used, the adjacent vehicles are skipped and erroneous communication with other vehicles occurs. May occur. Therefore, it is preferable to use a communication medium having a high linearity such as a light wave such as a laser beam or a millimeter wave (ultra short wave). Since such a communication medium is sequentially transmitted between adjacent vehicles, such a communication medium is used. Can reliably transmit information to the last car.

According to a seventh aspect of the invention, the leading vehicle allocates a time slot for each corresponding vehicle by time division of the predetermined period, and transmits to the following vehicle on the basis of the time slot. The following vehicle is characterized in that it responds to the preceding vehicle and transmits to the following vehicle based on the time slot assigned to each vehicle. According to this invention, since transmission or reply is made to an adjacent vehicle based on a time slot assigned to each vehicle, there is no possibility of causing interference even when there are many following vehicles, and information is transmitted even when frequent transmission and reception are performed. Transmission can be performed efficiently.

According to an eighth aspect of the present invention, in a communication system between vehicles in which a leading vehicle and a plurality of following vehicles travel in a row, the leading vehicle transmits to a following first following vehicle at predetermined intervals, and the first following vehicle transmits. When the first following vehicle receives the information from the leading vehicle, it returns the information to the leading vehicle and also transmits the information from the leading vehicle to the subsequent second following vehicle, and the second following vehicle transmits the information from the first following vehicle. When the information of is received, it will reply to the first following vehicle,
The first follower vehicle will receive the second vehicle when the next reply to the leading vehicle is made.
The feature is that the reply information from the following vehicle is returned. According to this invention, when the first following vehicle receives the information from the preceding vehicle, the first following vehicle transmits to the following second following vehicle, so that the information from the leading vehicle is sequentially transmitted to each following vehicle. In this control cycle, a reply is sent from the first following vehicle to the leading vehicle and from the second following vehicle to the first following vehicle, but the first following vehicle makes a next reply to the leading vehicle (when replying in the next cycle). To the second
Since the reply information from the following vehicle is returned, the reply information of the second following vehicle can be transmitted to the leading vehicle by repeating the control cycle.

As described above, since information is sequentially transmitted to each following vehicle using the leading vehicle as a synchronization source, transmission and reception do not interfere with each other. In the leading vehicle and each following vehicle, depending on the reply information, It is possible to confirm that the information has been normally transmitted up to the last car, and a highly reliable and efficient communication system can be realized. In the present invention, the number of following vehicles may be two or more (the number of vehicles traveling in a row is three or more). In that case, the second following vehicle transmits sequentially to the following vehicles, and the following vehicles send back a reply. The reply information may be sequentially transmitted by a similar method, and the tail car may not be transmitted and may be a reply only. According to this invention, when three vehicles run in a row, information can be efficiently transmitted to each succeeding vehicle by using the leading vehicle as a synchronization source, and the leading vehicle can normally transmit information to the last vehicle. You can confirm that it was transmitted.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be exemplarily described in detail below with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention unless otherwise specified, and are merely illustrative examples. Only. FIG. 1 is a main part configuration diagram showing a portion corresponding to the present invention extracted from the configuration diagram of the automatic tracking system of FIG.
On the rear surface side of the leading vehicle A operated by the driver 12,
The transmitter / receiver unit 16A of the front-rear communication device 16 is also provided on the front side and the rear face side of the follower vehicle B ₁ which is guided and steered by the leading vehicle A, respectively.
B is provided. In the drawings of the present embodiment, the characteristic portions are shown focusing on the functions of the leading vehicle A and the following vehicle B ₁ ... However, in an actual vehicle, each vehicle can be a leading vehicle or a following vehicle. It has the same configuration,
The vehicle to be the leading vehicle recognizes that the vehicle is the leading vehicle by a switch operation or a driving operation of the driver. Reference numeral 21 in FIG. 3 is a display unit such as an OCR.

FIG. 4 is a block circuit showing the internal configuration of the communication control unit 14 and the transmitting / receiving section 16A of the leading vehicle A. The communication control unit 14 includes a CPU 51 that performs central processing control, a ROM 52 that stores an operation program, an R that stores vehicle data and other company data.
AMs 53 and 30 are frame memories that store control data such as time slots in addition to the traveling data such as own vehicle data and other vehicle data stored by the RAM 53. As the own vehicle travel data, travel data of the brake 13d, the vehicle speed sensor 56, the engine 13b, the T / M 13c, the steering 13a, etc. is stored in the RAM 5 via the interface 571 or the like.
3 is stored.

Reference numeral 54 is a cycle setting circuit for setting the communication cycle t of the vehicle group, 55 is a cycle correction circuit for correcting the communication cycle t based on the vehicle speed signal from the vehicle speed sensor 56, 57.
Is a time division circuit that sets the time slot by time division of the corrected communication cycle t. Reference numeral 58A denotes a communication control circuit, which performs parallel / serial conversion of the data in the frame re-memory on the basis of the time slots time-divided by the time-division circuit 57, and the interface 6 of the transmitting / receiving unit 16A.
6 to the transmission control circuit 64, and based on the modulation data modulated by the transmission control circuit 64, the laser oscillator 6
5 is driven and data is transmitted to the following vehicle by optical communication. On the other hand, after the received light signal received from the following vehicle B ₁ ... Is converted into an ON / OFF signal by the light receiving sensor 62, the communication control circuits 58A, 58B are passed through the reception control circuit 61 during the corresponding time slot R ₁ . The data is transmitted to the RAM 53 through the RAM 53, rearranged in the RAM 53, and then transferred to the frame memory 30.

FIG. 5 is a block circuit showing the internal structure of the communication control unit 14 and the transmitting / receiving sections 16A and 16B of each following vehicle B ₁ . To describe the difference from FIG. 4, since the transceivers 16A and 16B of the front-rear communication device 16 are provided on the front side and the rear side of the follower vehicle B _1, ..., The communication control circuit 58A, Two 58Bs are provided, and since the time slot R _{1 for} transmission / reception is obtained from the leading vehicle A, the cycle setting circuit 54, the cycle correction circuit 55, and the time division circuit 57 are not provided. Reference numeral 60 is an interface, and 63 is a CPU.

FIG. 6 shows the structure of the frame memory 30,
SOF is the head control memory of the frame, and flag 1 is set here.
By grasping, it is understood that the data transmitted is the transmission data transmitted from the vehicle ahead. The second-order memory unit is the vehicle data storage unit 30A, which is a leading vehicle A and a following vehicle B.
Each vehicle traveling data of ₁ , B ₂ , B ₃ is stored at each predetermined address position. The CRC is a control code memory in which the communication cycle set by the leading vehicle A and the time slot R ₁ ... Data obtained by time-sharing the synchronization source are stored. EOF is a tail control memory of the frame, and by setting flag 1 here, it is understood that the data transmitted is reply data transmitted from the vehicle behind. In the vehicle data storage or EOF, the last following vehicle B
_It is better to provide bit data that indicates the type of ₁ ...

FIG. 7 shows the relationship between the time slots R ₁ ... And the communication cycle t. The time slot R ₁ is set by time-dividing the cycle t by at least one more than the number of vehicle groups. (In this embodiment, five time slots R ₁ ... Are set for three vehicles.) In the first period T ₁ , the leading vehicle A is time slot R _1.
In the frame memory 30 to the tracking vehicle B ₁ from the transceiver 16A
Send the data in. On the other hand, the follower vehicle B ₁ receives the signal in the time slot R ₁ , and in the time slot R ₂ , the leading vehicle A and the follower vehicle B from the transmitter / receivers 16A and 16B on the front and rear sides.
₂ data in the frame memory 30 to respectively send to, leading vehicle A and follower wheel B ₂ in the time slot R ₂ receives the signal. Further, the follower vehicle B ₂ transmits data in the frame memory 30 to the follower vehicle B ₁ and the rear side from the transceiver units 16A and 16B on the front and rear surfaces in the time slot R ₃ , but from the rear in the time slot R _4. Since there is no reply information from the following vehicle, it is recognized as the last vehicle.

The synchronization source period t is constructed so that it can be changed proportionally or stepwise in accordance with the vehicle speed of the leading vehicle A. For example, as shown in FIG. 8, the leading vehicle A vehicle speed v is 10
When the vehicle speed is less than km / h, the communication cycle t is 350 msec. When the vehicle speed v of the leading vehicle A is 10 to 20 km / h, the communication cycle t is 175.
msec, or less (v20 to 30 km / h) / (t: 11
7 msec) ...

The operation of the present invention will be described below with reference to the flow charts of FIGS. 9 and 10. FIG. 9 is a flow chart showing the operation of the leading vehicle A. After the vehicle speed of the leading vehicle A is detected, a cycle t based on the vehicle speed shown in FIG. 8 is set. (S
1) Next, the synchronization source is time-divided to set the time slots R ₁ ... Shown in FIG. (S2) The traveling data of the own vehicle is fetched from the interface 57 shown in FIG. 4, stored in the RAM 53 memory, and the content thereof is transferred to the frame memory 30 and updated. (S
3) Then, when the time slot is R ₁ , the frame memory data is transmitted from the laser oscillator 65 of the transmitter / receiver 16A to the following vehicle B ₁ as optical data, and the latest data of the leading vehicle is transmitted to the following vehicle B _1. It (S4) When receiving the optical data signal relating to tracking vehicle data from the following vehicle B ₁ in the time slot R _2, and stores the received data in the RAM53 memory, and update transferred to the frame memory 30 (S5) Further, a change in vehicle speed is further detected, and when the vehicle speed changes, the synchronization source cycle is corrected based on FIG. 8 (S6), and the process returns to step (S2) for time division.

On the other hand, when the optical data signal from the follower vehicle B ₁ is not received in the time slot R ₂ , it is determined that there is no follower vehicle (S7), and the process returns to (S1) and repeats the above operation. (In this case, if it is determined that there is no following vehicle by repeating a plurality of times, the transmission may be stopped.)

FIG. 10 is a flow chart showing the operation of the following vehicle B ₁ ..., Incorporating the traveling data of the own vehicle from the interface 57 shown in FIG. 5 (S11), and the RAM 53.
The contents are stored in the memory, and the contents are transferred to the frame memory 30 and updated. (S12) Then, when there is a reception from the leading vehicle A, first, the time slots R ₁ ... Are set in the communication control circuits 58A and 58B (S13), and further, the leading vehicle A data is stored in the RAM 53 memory, and at the same time, The contents are transferred to the frame memory 30 and updated. (S14)

Next, when the time slot is R ₂ , the frame memory data is transmitted from the laser oscillators 65 of the transmitter / receivers 16A and 16B on the front and rear sides of the vehicle to the leading vehicle A.
And transmitted to the following vehicle B ₂ as optical data. (S
15) When the optical data signal from the following vehicle B ₁ is received in the time slot R ₃ , the received data is stored in the frame memory 30.
Transfer to and update. (S16) On the other hand, when the optical data signal from the following vehicle B ₁ is not received in the time slot R ₃ , the own vehicle is recognized as the last vehicle and the information is transmitted to the frame memory 30. (S
17) On the other hand, the operation of the following vehicle B ₂ is the same as that in FIG. 10, and therefore its explanation is omitted. Here, as a result of the above-described operation, the frame memory updating operation executed in each vehicle will be described in detail with reference to FIG. 7. In the time slot R ₁ of the first cycle T ₁ , the information from the leading vehicle A will be described. Follower car B ₁
The data of the leading vehicle A in the frame memory of is updated to the latest value. In the subsequent time slot R ₂ , the following vehicle B ₁ portion of the frame memory of the leading vehicle A is updated to the latest value, but at this time the following vehicle B ₁ does not store the latest data of the following vehicle B ₂ , so the following vehicle The latest data of B ₂ is the leading car A
Is not remembered. At the same time slot R ₂ , the following vehicle B ₂ obtains the latest data of the leading vehicle A and the following vehicle B ₁ and updates the frame memory. Tracking vehicle B ₂ portion in the frame memory of the time slot R ₃ in tracking vehicles B ₁ continues to be updated to the latest data. Although basically the same operation is performed also in the subsequent second period T _2, in particular the time slot R _2, tracking vehicles B ₁ is received from the following vehicle B ₂ in the first period T _1, following vehicle B ₂ Data of the following vehicle is transmitted to the leading vehicle A, the frame memory in the leading vehicle A is updated with the latest data of the following vehicle B _{1 and} the data of the following vehicle B ₂ one cycle before. In this way, the information from the preceding vehicle is sequentially transmitted to the following vehicles. In addition, the information from the following vehicle is transmitted only to the preceding vehicle in the same cycle, but by repeating the cycle, it is sequentially transmitted to the preceding vehicle, so that each vehicle can accurately grasp the data of other vehicles, and the information transmission is ensured. The lead car can also confirm what has been done. As a result, the data of other vehicles stored in each vehicle is sequentially updated. Therefore, by utilizing the other vehicle data, the accuracy of platooning is improved. In the above-mentioned embodiment, the case where three vehicles run in a row has been described, but if a following vehicle that performs the same operation as the following vehicles B ₁ and B ₂ joins as a further succeeding vehicle, four or more vehicles follow. It is also possible to drive in vehicles.

[0035]

As described above, according to the present invention, the invention can be effectively applied to a system for controlling traveling while frequently transmitting and receiving between the leading vehicle A and the following vehicles B ₁ . Further, according to the present invention, an effective transmission / reception interval can be set even if the speed of the leading vehicle fluctuates.

[Brief description of drawings]

FIG. 1 is a main part configuration diagram in which a part corresponding to the present invention is extracted from the configuration diagram of the automatic tracking system in FIG.

FIG. 2 is a schematic view of an image of a vehicle group traveling system applied to the present invention.

3 is a configuration diagram of an automatic tracking system as a communication system of the vehicle group traveling system of FIG.

FIG. 4 is a block circuit showing an internal configuration of a communication control unit and a transmission / reception unit of the leading vehicle.

FIG. 5 is a block circuit showing an internal configuration of a communication control unit and a transmission / reception unit of each following vehicle B ₁ .

FIG. 6 shows a configuration of a frame memory.

FIG. 7 shows the relationship between time slots R ₁ ... And synchronization source T ₁ ... Cycle t.

FIG. 8 shows a relationship between a leading vehicle speed v and a synchronous source period t.

FIG. 9 is a flowchart showing the operation of the leading vehicle.

FIG. 10 is a flowchart showing an explanation of the operation of the following vehicle B ₁ .

[Explanation of symbols]

12 Driver 13a Steering 13b Engine 13c T / M 13d Brake 14 Communication control unit 16 Front-rear communication device 16A, 16B Transmitter / receiver 30 Frame memory 51 CPU 52 ROM 53 RAM 54 Synch source setting circuit 55 Synch source correction circuit 56 Vehicle speed sensor 57 hours Dividing circuit 58A, 58B Communication control circuit 61 Reception control circuit 62 Light receiving sensor 64 Transmission control circuit 65 Laser oscillator A Leading vehicle B ₁ ... Following vehicle t Synchronous source period R ₁ ... Time slot

Claims (8)

[Claims] 1. In a communication system between vehicles in which a leading vehicle and a plurality of following vehicles travel in a row, the leading vehicle transmits to a following vehicle immediately after every predetermined period, and each following vehicle is an adjacent forward vehicle. When receiving information from, it sends back information to the preceding vehicle and sends information from the preceding vehicle to an adjacent succeeding vehicle, and when replying to the preceding vehicle, returns previous reply information from the following vehicle. Communication system between vehicles. 2. The leading vehicle transmits its own vehicle data to an immediately following vehicle, and each of the following vehicles transmits the preceding vehicle data and the own vehicle data when transmitting to the following vehicle, and transmits to the preceding vehicle. The vehicle-to-vehicle communication system according to claim 1, characterized in that the vehicle data and the following vehicle data from the previous response from the following vehicle are transmitted at the time of reply. 3. The following vehicle according to claim 1, characterized in that when there is no reply from the following vehicle, the following vehicle recognizes itself as the last vehicle and responds to the preceding vehicle. Communication system between vehicles. 4. The leading vehicle is driven by a driver, and each of the following vehicles is automatically driven based on information obtained from the leading vehicle directly or via a forward following vehicle. A communication system between vehicles according to the first item of the range. 5. The vehicle-to-vehicle communication system according to claim 1, wherein the leading vehicle sets the predetermined period to be short as the vehicle speed increases. 6. The communication system between vehicles according to claim 1, wherein the communication between the adjacent vehicles is performed using a light wave or a millimeter wave as a communication medium. 7. The leading vehicle allocates a time slot for each corresponding vehicle by time division of the predetermined cycle, and transmits to the following vehicle immediately after based on the time slot, and each of the following vehicles transmits for each vehicle. The vehicle-to-vehicle communication system according to claim 1, wherein a reply to the preceding vehicle and a transmission to the following vehicle are performed based on the assigned time slot. 8. A communication system between vehicles in which a leading vehicle and a plurality of following vehicles travel in a row, wherein the leading vehicle transmits to a following first following vehicle at predetermined intervals, and the first following vehicle When the information from the leading vehicle is received, the information is returned to the leading vehicle and the information from the leading vehicle is further transmitted to the following second following vehicle, and the second following vehicle receives the information from the first following vehicle. Reply to the first following vehicle, and the first following vehicle will reply to the second vehicle when replying to the leading vehicle next time.
A communication system between vehicles characterized by returning reply information from the following vehicle.