FR2470193A1 - ROAD SIGNALING DEVICE AND METHOD OF USING SAME - Google Patents

Abstract

COMPOSITE ROAD SIGNALING PROCESS AND DEVICE. ELECTRONIC TRANSMITTER-RECEIVER COMPONENTS, CALLED "SECONDARY RADARS", ARE PLACED ON BOARD VEHICLES V AND ARE SUITABLE TO EMIT ENERGY TO THE ROAD. PASSIVE COMPONENTS ARE ARRANGED IN A PREFABRICATED S, S BAND ON THE ROAD AND ARE SUITABLE TO RETURN THIS ENERGY TO THE RECEIVING COMPONENTS ON BOARD VEHICLES, PROVIDING ELECTROMAGNETIC INFORMATION.

Description

The present invention relates to a device which, as a whole, is

  formed from the association of several components

their respective active and passive electronic components,

joint, to provide information in electroma-

genetic, and horizontal signaling components suitable for providing optical information. The present invention

also relates to a process in view of the use of such a device.

  positive in the context of road signs.

As a result of the ever increasing increase in road traffic and the tendency to increase the speed of vehicles even more, the problem of road signs, which translates into complete information provided by the road to the drivers of vehicles, becomes more and more more difficult to solve? we consider it essential

to systematically structure this information, in order to

improve the reliability of the information that must be provided to drivers, to warn them, for example, of approaching dangerous crossings, equally dangerous passages or sections, etc. This problem is still far from being resolved, despite all the proposals and all the attempts that have been made. At the present time, it is mainly proposed to install active emitting components placed at critical points on the route and which are able to send the desired information

  k receiver components installed on board vehicles.

This solution is complex and extremely expensive, both because of the number of active components necessary to protect

critical points and locations, only because of the need

  sity of continuous operation and the problem of feeding

  tion and control. It goes without saying that the absence or non-

  reception of a critical signal may result in

very serious accidents.

  Furthermore, it must be recognized that the signa-

  current road layout, both vertical and horizontal -

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  the latter more effective - is still far from offering

a rational solution to the problem under consideration.

  Current signaling, with the exception of very rare cases of acoustic signals between vehicles, is based exclusively on the visual perception of the signals and on

  the constant attention of the eyes on the road to follow.

This visual perception is influenced by the conditions

  visibility, which is itself influenced by seasonal and weather factors; it is currently considered that the essential condition for the future of road traffic safety is to provide vehicles with means capable of receiving, decoding and signaling to the driver (and / or, possibly, the instruments of the

  vehicle) signaling information.

  The invention consists in the association of active emitting components installed on board vehicles, called

I secondary radars ", and passive components, in particular

  culier of dip8les selectively and appropriately placed

required under a prefabricated laminar signaling layer

  and placed on the road, or under (or in) the

layer carrying the signaling material, these dip8les

  receiving energy from the vehicle's secondary radar which is approaching

  che and return it, providing the information in the desired electromagnetic form, while the material

  signaling gives the required optical information.

We know that these secondary dip8les, called "responders" or "responders", can be constituted by very simple resonance circuits, formed, in their most

simple, with very thin metal plates, the size

  desired ion with respect to the wavelength of the energy

emitted by the secondary radar.

  It has been found that the prefabricated strips known for horizontal signaling constitute, as well as the corresponding sub-layers, load-bearing or sticky, put in place with the strip, an ideal support for these responder dipoles. These prefabricated bands or ribbons, with their secondary dipoles, oriented and staggered after their installation on the roads, preserve, without alteration,

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  their horizontal signaling function and form, with the di-ples placed under the signaling layer proper as many passive answering means, and, as such, they do not require any clean energy to power the resonance circuit.

To provide additional information, this circuit

  resonance baking will preferably be equipped with a variable oscillating circuit, provided with a "Schottky" diode, circuit

which modulates the response beam.

The importance and the advantages of the invention are as follows: The information received by the active receiving component, on board the vehicle, depends exclusively on the existence and the presence of the responder dip8le, which simply enters into resonance when it receives energy from the secondary radar

approaching.

  The amount of information can be increased not only by the modulation of the response beam but also by

additional resonance elements, also

killed by metal plates. The dip8les prescription

  secondary to be distributed along the route can be 9

encoded and decoded by a computer coupled to the active transmitting and receiving unit, to selectively and unequivocally provide the desired response. We know that we use

  more and more radar equipment to avoid colli-

sions in the fog; it is easy to understand the advantage that can be drawn from the transformation of such equipment into

view of their use according to the present invention.

  Important information can also be provided on weather conditions. For example, the presence of ice in a cavity placed on the circuit of the

  dip8le significantly alters the values of the

  ponse thus providing very important information (the presence of ice on the road) a

  Many other additional information can be obtained.

2470193 -

by associating with the system, in particular, the active component, a source of infrared radiation, which

  can be returned and duly modulated by passive components.

  In United States patent no. 4,129,397 in the name of the Applicant is described a signaling strip, comprising catadieptic elements, which can be easily transformed and adapted to reflect infrared energy. It is well known that with this energy, suitably modulated, we can

get endless types of information.

In addition, given the speed and simplicity with which it is possible to install the signaling strips, even temporarily, on road surfaces, the system which is the subject of the present invention not only makes it possible to obtain, on a continuous basis , localized information and

  preprogrammed, but can also provide provi-

evening and discontinuous, as, for example, signaling to the conduc-

  tutors of interruptions, works, ec.

  An embodiment of the invention is described below in relation to the drawings in which s - Figure 1 represents a section of road "A", carrying a signaling strip, equipped with a series of dip8les constituting as many resonance circuits;

- Figure 2 shows part of a strip "S" for-

view of an SD "dipole and consisting of a small aluminum plate

minium; FIG. 3 represents part of a variant of the dipole equipped with a variable oscillating circuit "DSut and - FIG. 4 represents, schematically and partially,

an example of additional coding.

We see in Figure 1 a vehicle "V" equipped with a secondary radar placed so as to present a dip8le antenna

mounted underneath the vehicle, the vehicle approving from

run the road "To", in the direction determined by the

horizontal signage.

The active component "R" is equipped to decode the information

mations provided by the waves re-emitted by the dip81es (examples of which are reproduced in FIGS. 2 and 3), which reopen in the signaling band "S" (for simplicity, we have indicated only one band along the road). This strip may be discontinuous or continuous, as indicated, by S1 and S2 respectively to indicate the information of authorized overshoot or of

No passing. The corresponding information (respec-

uninterrupted sequence of signals and short sequences of signals) is given to the vehicle by the component

active 'Rl ,.

  The above gives an example of basic cndago. Figure 4 provides an additional coding example, where various signal sequences, for example, a uniform CI sequence, relate the response to vehicle speed while various groupings G1, G2 and G3 have established coded meanings. The resonance circuit, made up of l1s dip8les, re-emits energy in several harmonics, of which, preferably, the third, that is to say the strongest, is exploited In order to give the antenna of the resonance circuit proportional dimensions, the band which contains, between its layers, the thin-striped dip81es, we naturally adopt rather high frequencies0 For example, the transceiver, that is to say the secondary radar, which, at vehicle edge, forms the active component

  of the system, preferably uses, in transmission, micro-

waves between 0.6 and 1.2 GHZ (Gigahertz).

In practice, for best results, the transmitting antenna and the resonance dipole are arranged transversely to the signaling band. This fact implies a limitation of the minimum frequency (a right dip8le, of

  cm long, corresponds to a frequency of 600 MHz).

- This limitation does not exist for high frequencies, apart from the higher cott, of a greater sensitivity to

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  humidity and increased material loss coefficients. In practice, these will be the frequencies

adopted for anti-collision radar equipment which deter-

  will undermine equipment frequencies.

  For example, with a 1 GHz transmitter, a power

0.5 Yatt, at a distance of 5 m from the signal strips

reading, we obtained, with a vehicle traveling at 20 km / h and

on a dry pavement, an answer, on the third harmoni-

  that, 1.4 microvolt, while, on a wet road, the

response was 1.55 microvolt.

  It goes without saying that the composite device has been described and represented by limiting itself to its essential components, by way of

indicative but not limiting example.

  The passive directions, indicated by the letter "D" in Figures 2 and 3, can have a different shape and design, while retaining their property of forming a resonance circuit, responding to the signal emitted by the secondary radar "R" . The same applies to the characteristics of the secondary radar, which may vary, while using

however frequencies.

  Similarly, the wagering methods may be modified.

passive dipoles, placed under the signature strip

prefabricated, possibly in the form of a ribbon

slipped into the sticky undercoat ("primer") of the strip.

  The installation of such a prefabricated strip,

  dant, under the signaling layer, the passive resonance elements, gives this band a double function z visually identifiable horizontal signaling and, through elements selectively in resonance with

  the secondary radar, information in electroma-

genetics

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Claims (10)

IONS CLAIMS   1. Composite road signaling device,   characterized by the association (a) of electronic components   ques (R) transceivers, called "secondary radas" intended to be placed on board vehicles (V) and capable of emitting energy towards the road (b) of passive components, arranged under a strip (Sp 82 ) prefabricated, provided on the   road, capable of returning this energy to the receiving components on board vehicles, providing electromagnetic information and, finally, (c) horizontal signaling components, capable of providing the motorist with optical information. Composite device according to claim 1 for providing signaling information on already existing roads. provided with horizontal signage materialized by   prefabricated signaling strips, distributed over the revS-   road structure, characterized in that passive components are directly associated with the signaling material formed by a ribbon.   3. Composite device according to claim 1 or 2 and / or 2, characterized in that the passive components are dip3les whose dimension and orientation are such that these components remnvoiemnt the energy to the receiving components on board the vehicle, 4. Composite device according to any one of   previous claims, characterized by the fact that said   components act in the radar frequency domain * Composite device according to claim 4, charac-   terrified by the fact that the passive responder components see signal harmonics   6, Composite device, according to any one of the re-   vendications 1 to 5, characterized in that the active components are constituted by secondary radars whose antenna is directional and is placed below the vehicle, in order to emit energy in the form of microwaves directed towards the passive answering components, placed on the roadway, in this direction. 7. Composite device according to any one of the res-   dications 1 to 6, characterized in that the component   receiver includes a computer for decoding and ex- use of the information supplied by the microwaves re-emitted by the passive answering components found on pavement.   8. Composite device according to any one of the res-   dications 1 to 7, characterized in that the passive responder components are provided with an oscillating circuit of variable resonance. 9. Method for the use of composite devices according to any one of claims 1 to 8, characterized   by the simultaneous operation of passive components, forming dip8les, placed under a signaling strip, to send signals produced by secondary radars mounted on vehicles, in order to provide them with signaling information in electromagnetic form, as well as a horizontal signal strip, in order to   provide these vehicles with optical information.   10. The method of claim 9, wherein the composite devices comprise passive dipoles buried in the signaling bands placed on the roadway, characterized by the use of the response signals of said dip8les, signals which correspond to visual signaling read by the horizontal signage in place.   11. Method according to claim 9 or 10, characterized by the exploitation of the information returned by the passive responder components, in order to obtain indications on the state of the roadway. 12. The method of claim 11 characterized by the detection of a freezing condition in a cavity associated with the dip8les circuit, to obtain information on the condition of the roadway, in particular, on the presence or absence ice on the road. 13. Method according to any one of the claims   9 to 12, characterized by the use of a computer for decoding the response signals from the dipoles, in order to obtain signaling information 14. Method according to any one of the claims   9 to 13, characterized by the use of auxiliary information binders provided by the msodulated reflection of infra-energy red, from reflectors arranged on the roadway and struck by the radiation emitted by an optical source placed on the vehicle, in order to obtain additional information shut up? those obtained by selective reflection of micro- radar waves 15. Composite DispasitUi to provide information signaling, on roads already equipped with a   horizontal position materialized by signaling strips   your prefabricated, distributed on the road surface   characterized by the fact that passive components are associated   directly to the signaling material formed by a tape.