FR2566349A1 - Static device for the dynamic identification of a vehicle passing over a track. - Google Patents

Abstract

Device for identifying vehicles, characterised in that each vehicle 2 has an electronic marking 1 in two zones, one fixed and the other movable, and in that an appliance 14 and 17 which is fixed relative to the track may read and write all or part of the contents of the badge.

Description

Various vehicle detection devices are known. We will quote
Among these
- passive induction loops which detect the passage of a mass
magnetic without being able to identify it.

 - the receiving antennas embedded in the roadway which receive permanent active emissions from certain vehicles, for example, buses to manage traffic lights or groups of traffic lights.

- pneumatic tubes or groups of tubes to detect the passage of axles
- piezoelectric sensors buried in the roadway which can be used to obtain the weight of the axles or to evaluate it with an accuracy of +/- lo%. This dlynamic sensor makes it possible to obtain the physical quantities described above during the passage of the vehicle.

 - capacitive sensor of the coaxial type giving results similar to piezoelectric sensors.

 - triboelectric sensor.

 - shape recognition.

The proposed technique - consists of electronically marking each vehicle and recognizing it when it passes. The marking of the vehicle can be carried out on the whole population or on groups or sub-groups of vehicles 9 for example: subscribers to a motorway company or a parking company or priority vehicles of a set of localities (buses, taxis, firefighters, police ...)
The marking will be done in two separate areas as needed
- fixed area allowing to recognize the vehicle and / or its type. This part will be indelele. Certain specific systems will allow the initial writing on the badge or the writing by an organization, authenticating certain data additional data that are significant in the life of the vehicle.

 - variable area that can be written, read or erased outside the vehicle and at any time, and can only be read from the outside.

 The description and the example of use which will follow will make it possible to better understand the operation of the inventions subject of this patent and its use.

 The electronic marking is in the form of a plasticized badge (1) containing an electronic system without external energy source fixed under the vehicle (2) by means of a fixing part (3). The badge badge does not contain any external or internal energy source except that which is picked up through the antenna (4) and carried by the Low Frequency wave received by the badge.

The "badge" is composed of the following elements (fig. 2)
- a receiving antenna (4) of low frequency code waves.

 - an energy storage system (6) making it possible to store part of the energy received by the antenna (4) at very low voltage.

 - a system (5) intended to decode a possible message transmitted by the LF wave received on the antenna (4).

 - the ineffaceable memory (7) which will be programmed at the start and some areas of which could be modifiable by certain organizations.

 - a memory area (8) which can be written from the amplitude and / or frequency modulations received by the antenna (4) and decoded by the system (5).

 - a high frequency wave transmission system (9) intended to transmit all or part of the content of the memories (7) and / or (8) to the outside through an antenna (10).

 - a logic and control unit (11) intended to control the whole operation of the badge.

Different external systems (fig. 3a and 3b) allow communication with the badge as follows
An antenna (12) formed for example by a loop of several turns buried in the ground (13) is connected to a generator (14), supplied with energy by the cabal (15).

 A vehicle passage detection system (18) which can also be buried in the ground, is connected to the generator (14). During the passage of a vehicle, the detector (22) (fig. 4), connected to the sensor (18) by the target (19) sends an impulse to the steering device (23) which then activates the power generator (24) whether or not coding the low frequency wave to be emitted p this electric wave is transmitted to the antenna (12) via the target (20). The Low Frequency broadcast is then received by the vehicle during its passage.

Depending on the case, the modulation of the Low Frequency carrier wave can be of several types
- without modulation: simple energy to power or refresh the badge.

 - modulation requesting a reading of the badge.

- modulation transmitting a very short message
The badge being devoid of internal energy, the wave train must have a variable shape in the. time.

- pure energy resignation wave
- energy emission wave with a message superimposed on it
The antenna placed in the ground or near the vehicle will be of sufficient size to transmit the maximum energy. It cannot however be too large so as to take into account only one vehicle at a time.

 In the first case, the energy will be stored in the storage capacity of the badge.

In the second case, the badge after having received a little energy emitted by (12) and received by (4), continues to store the energy emitted in (6) while decoding the message by (5) giving the total or partial transmission instruction with or without erasure of the temporary memory area (s)
The instruction received and decoded, the badge uses the energy stored in <6) to transmit by the amplifier (9) and the antenna (10) the partial or total content of the memories (7) and (8) L ' entire operation is managed by the unit (11),
The emission will be done in High Frequency so as to require little energy for a range of a few tens or hundreds of meters.

 The modulated waves will be received by the antenna (16) placed on the receiving device (17). The message will be decoded by the receiver (17) and can thus be directed to an appropriate processing device.

 In the third case, a message can be transmitted by the system (14) to the vehicle O The process will be the same as above and the message will be stored in the temporary and erasable memory (8).

 One can also imagine (see Figure S3) a device where the reception transmit antennas and the vehicle detection would be combined in a single system buried in the ground.

The list of applications below is not exhaustive and allows you to appreciate the wide field of application of the system.
1 / dynamic toll for motorways, tunnels ...

 The application - can be made either for all vehicles in circulation or for subscribers of different motorway companies.

 In the first case, the badge stores in immutable memory the vehicle number and its category and receives the station number as input.

At the output, we read the vehicle number, its category and its provenance. We can thus automatically determine the fees to be paid. Payment can be made at the outlet or monthly by invoicing.

In the second case, the badge carries by eymple in unalterable memory the subscriber number and receives as input the station number. At the output we read the reference of the vehicle and its provenance. B1 is thus able to automatically determine the rights to be paid and to carry out invoicing without stopping the vehicle for a moment. The gains brought by such a system are considerable
- toll staff
- reduction in waiting times at tolls, therefore increased traffic flow.

 2 / Access of certain vehicles to given areas.

 The badge carries an unalterable memory with an identification number and a number corresponding to the authorized zones. This data can allow access to different areas of a set by reserving certain parts for certain vehicles.

 The erasable part can receive the time entered in a zone, time which will be read out.

 3 / priority control of lights.

 The fixed data, which may be of the same nature as above, make it possible to switch to a priority vehicle of level O (firefighter, ambulance) on a priority vehicle (1), for example public transport.

 4 / Control of payment of the vehicle tax.

 The sticker system would be replaced by an annual marking of the badge with. a specialized body equipped to register the year of tax payment on the badge. The control could then be very automated and systematic.

 5 / Automatic verification of certain offenses.

 The infringing vehicle can be easily identified by its badge.

 6 / Monitoring of the vehicle space.

 One of the most common causes of motorway accidents is the small space between two vehicles following each other. The offense can only be noted if this small space is maintained for a sufficient distance, for example, 500 meters or t km. We can therefore imagine placing two stations (25 and 26) at a distance (29) of 500 m X 1 km. Each station is made up of a distance measurement device between vehicles (28) and a vehicle identification system (27). It is thus possible to know that the vehicle (A) follows the vehicle (B) at (25) and that it always follows it year (26) or that it has doubled it.

 7 / Technical monitoring of vehicles.

 This system could work in the same way as for the vehicle tax.

 During each technical visit, a special device would allow this visit to be recorded on the badge in non-erasable memory.

 8 / Follow-up of routes for the purpose of sizing roads.

 Manual surveys could very easily be replaced by such a system with much greater reliability.

 Interrogation and data collection devices (30) can be installed on the various access routes of a given route making it possible to know the route of the vehicles. Traffic flows can thus be perfectly identified.

Many other applications in the automotive and other fields can be considered.

Claims (5)

 1 / Vehicle recognition device characterized in that each vehicle carries an electronic system devoid of its own permanent energy source comprising an unalterable fixed memory area and a variable area and that the content of the variable area can be entered in writing from a device fixed relative to the roadway, the content of the fixed and variable areas can be read from the same device fixed relative to the roadway; the energy necessary for the operation of the device on board a vehicle is transmitted to it by an electric wave emission controlled and generated by the device fixed relative to the roadway.  2 / Device according to claim 1 characterized in that the activation energy of the on-board system is transmitted by a low frequency wave modulated or not.  3 / Device according to claim I characterized in that the messages sent by the on-board system are transmitted at high frequency.  4 / Device according to claim b characterized in that the messages tarnished by the on-board system are transmitted at very high frequency.  5 / Device according to claim 1 characterized in that all of the elements on board the vehicle are sealed in a sealed plastic envelope and fixed under the vehicle.