EP1555643B1 - Mobile information preventive system with respect to speed - Google Patents

Abstract

The device has a processing unit for extracting and recognizing a registration number of a vehicle from an image acquired by a camera (103). The camera acquires the image if vehicle speed measured by a speed detector is greater than a threshold. The camera and the detector are mounted on a post comprising an upper part (100b) that revolves around a horizontal axis till its rear side contacts with rear side of a lower part (100a). An independent claim is also included for a land vehicle identification and speed detection system comprising a land vehicle identification and speed detection device.

Description

The invention relates to a mobile system for detecting and possibly displaying the instantaneous speed of vehicles and their registration number ("plate number"). More specifically, it concerns a system designed for preventive purposes, to encourage users of roads and highways to slow down when approaching sites where other areas in which a temporary speed limit is in force. Although this is not its main purpose, such a system may also have a repressive function, making it possible to observe speeding offenses.

Patent Application JP 6068376 discloses a system comprising a speed detector radar, a camera, an automatic license plate reading system and a variable message sign simultaneously displaying the speed and registration number of a vehicle . However, this is a fixed system, which is suitable when it is necessary to permanently incite road users to limit their speed, such as when approaching a dangerous turn, but not suitable for temporary use, such as on a job site that can be as short as one or two days.

U.S. Patent 5,231,393 shows a cart that can be transported near a job site and that includes a speed sensor radar and a variable message sign for displaying the speed of a vehicle. This device does not include means for acquiring, reading and displaying the registration number. In addition, the fact of fixedly combining the speed sensor and the display panel has major disadvantages. Indeed, even if the speed detectors can function effectively up to a distance of several hundred meters, such a distance does not allow the acquisition of an image with a definition sufficient to allow the reading of the plate (in all case, when the use of a flash is necessary, the image must be acquired at a close distance). It follows that a sign at the same location that the detector can display the speed of a vehicle at best a few moments before its passage: the driver does not have time to read the message, let alone recognize its plate number.

Substantially the same remarks are valid for Patent Application FR 2 601 144. This document presents two embodiments of the same device; the first embodiment is not easily transportable and the second embodiment is integrated with a vehicle. This latter solution allows for easy transportation, but requires expensive immobilization of a vehicle and limits the ability to choose the best location for the system.

Patent Application EP 1 148 457 describes a compact, transportable and equipped with wheels, comprising a speed detector and a camera and a flash triggered by the latter. However, this document does not mention automatic means of reading license plates or variable message sign to display the speed of vehicles and their plate number. A module of this type has the disadvantage that, to avoid excessive clutter, the camera is located at a relatively low level relative to the ground and can not be oriented freely (it is located inside the module, behind a window). This is an important limitation for an application in correspondence of a construction site, where many obstacles could intervene between the camera and a vehicle: people, tools, piles of earth or gravel.

In conclusion, none of the known devices of the prior art seems well suited to provide an easily transportable and positionable system for detecting and possibly displaying the speed of a vehicle and its registration number, particularly in the environment of the vehicle. a road or motorway project.

The present invention relates to a mobile device for speed detection and identification of land vehicles consisting of a carriage on which are arranged a camera and a speed detector, also comprising electronic control circuits for acquiring the speed of a vehicle measured by the detector and, if this speed exceeds a predefined threshold, triggering the camera to acquire an image of said vehicle, characterized in that it also comprises means for for extracting and recognizing the vehicle registration number of the image acquired by the camera, and in that the camera and the speed detector are mounted on a support extending vertically from a base which ensures the stability of the whole.

• le support comporte une partie inférieure fixée à la base et une partie supérieure connectée à ladite partie inférieure par des moyens de pivotement de manière à pouvoir pivoter d'environ 180° autour d'un axe horizontal, ce qui permet de replier le dispositif pour en réduire l'encombrement lors de son transport et de son entreposage;
• la caméra et le détecteur de vitesse sont fixés à la partie supérieure du support ;
• le support est un mât ;
• le support a une hauteur comprise entre 2 m et 3m, de préférence d'environ 2,50 m, car le présent inventeur s'est rendu compte que, sur un chantier, il est avantageux de placer la caméra et le détecteur de vitesse à une hauteur relativement élevée ; le support étant pliable, l'encombrement du dispositif lors de son transport et de son entreposage reste réduit;
• la base contient des batteries d'alimentation, ce qui rend le dispositif autonome du point de vue énergétique ; accessoirement, les batteries peuvent avoir une fonction de lest ;
• la base comporte des roulettes pour faciliter le transport du chariot ; et
• le support comporte des moyens de pivotement permettant un pivotement d'environ 90° autour d'un axe horizontal par rapport à la base, de manière à se disposer en position horizontale pour réduire ultérieurement l'encombrement du dispositif.

According to advantageous embodiments:

• the support has a lower part fixed to the base and an upper part connected to said lower part by pivoting means so as to be able to pivot about 180 ° about a horizontal axis, which allows the device to be folded in order to reduce congestion during transportation and storage;
• the camera and the speed detector are attached to the upper part of the support;
• the support is a mast;
• the support has a height of between 2 m and 3 m, preferably about 2.50 m, because the present inventor has realized that, on a site, it is advantageous to place the camera and the speed detector at a relatively high height; the support being foldable, the size of the device during its transport and storage remains reduced;
• the base contains power batteries, which makes the device stand-alone from an energy point of view; incidentally, the batteries may have a ballast function;
• the base has rollers for easy transport of the carriage; and
• the support comprises pivoting means allowing pivoting about 90 ° about a horizontal axis relative to the base, so as to be arranged in a horizontal position to further reduce the size of the device.

The experiments carried out by the applicant have demonstrated that the psychological effect of the display of the speed is substantially reinforced by a "personalization" of the message by simultaneously displaying the vehicle registration number.

• le dispositif mobile de détection de vitesse et d'identification de véhicules terrestres et au moins un panneau à message variable sont disposé au bord d'une route ;
• au moins un panneau à message variable est disposé en aval, dans le sens de la circulation, par rapport au dispositif mobile de détection de vitesse et d'identification de véhicules terrestres, et il est orienté de façon à être facilement visible depuis la route ;
• au moins un panneau à message variable reçoit du dispositif mobile de détection de vitesse et d'identification de véhicules terrestres la vitesse et le numéro d'immatriculation d'un véhicule qui roule à une vitesse supérieure à un seuil prédéfini et les affiche d'une manière lisible pour le conducteur dudit véhicule.

For this reason, another object of the present invention is a mobile speed detection and identification system of land vehicles for displaying their speed and their registration number, comprising a mobile device for detecting speed and for identifying land vehicles as previously described and at least one variable message sign, in which:

• the mobile device for detecting the speed and identification of land vehicles and at least one variable message sign are disposed at the edge of a road;
• at least one variable message sign is disposed downstream, in the direction of the traffic, with respect to the mobile device for detecting speed and identification of land vehicles, and is oriented so as to be easily visible from the road;
• at least one variable message sign receives the speed and registration number of a vehicle traveling at a speed above a predefined threshold from the mobile speed detection and land vehicle identification device and displays them in a legible way for the driver of said vehicle.

• la figure 1 montre une vue générale du système comprenant un chariot mobile et un panneau d'affichage, positionné sur un chantier autoroutier ;
• la figure 2 montre, plus en détail, le chariot mobile en position dépliée, prêt à l'usage ;
• les figures 3A et 3B montrent ce même chariot en position repliée, prêt pour être transporté ; et
• la figure 4 montre comment un seul opérateur peut transporter et positionner le chariot par roulement.

Advantageously at least one variable message panel is placed on a trailer equipped to be able to also contain and transport the mobile device for speed detection and identification of land vehicles.
Other characteristics, details and advantages of the invention will emerge on reading the description made with reference to the accompanying drawings given by way of example and in which:

• Figure 1 shows a general view of the system comprising a movable carriage and a display panel, positioned on a highway project;
• Figure 2 shows, in more detail, the carriage in unfolded position, ready for use;
• Figures 3A and 3B show the same carriage in the folded position, ready to be transported; and
• Figure 4 shows how a single operator can transport and position the carriage in rotation.

Figure 1 is a perspective view of a system according to the invention when used in correspondence of a motorway project. A carriage 1 is disposed on the emergency stop strip of the motorway, preferably in the initial part of the site, oriented in the direction of origin of the vehicles. A variable message display panel 2 is also disposed on the emergency stop strip, downstream in the direction of traffic relative to the carriage, and is oriented so as to be easily visible to the motorists. The distance between the carriage 1 and the panel 2 is typically between a few tens and a few hundred meters, its exact value being determined by considerations of space, visibility and safety.

In a preferred embodiment the panel 2 comprises a fixed panel "building site", two flashing orange flash and two or three lines of 10 variable characters, a height of 200 mm.

Preferably the panel 2 is mounted on a trailer 20, to be transported to the job site and positioned easily. Advantageously, the trailer 20 includes panel 2 power supply batteries (minimum autonomy of 24 hours) and can accommodate the carriage 1 in the folded position (see FIGS. 3A and 3B).

When a vehicle 3 enters the area covered by a speed sensor ("radar") 101 mounted on the carriage 1, it measures its speed. If the latter exceeds a predetermined threshold, an infrared flash 102 is triggered and a camera 103 takes an image of the vehicle 3. Then the image is processed by means 104 to extract the registration number ("plate""). The registration number and the speed of the vehicle are transmitted, preferably by radio link or GSM, at panel 2 which displays them, with an invitation to slow down; the message is maintained for a time sufficient to allow its reading, which may be fixed or dependent on the speed of the vehicle 3. When no speeding vehicle is detected, the panel 2 remains off, or it displays a reminder the speed limit.

The processing means 104 generally comprise a universal computer and an image processing and character recognition program. Such means are known, for example, from US 4,817,166 and US 4,878,248. It is important to note that, in a preventive application, a relatively high error rate on recognition of the registration number is permissible, which is not true in the case of a repressive application. By way of example, it can be estimated that a plate recognition rate of 90% with an intensity of 100 vehicles / hour and 60% with an intensity of 1500 vehicles / hour would be sufficient for the present application.

It is observed that the speed sensor 101, the flash 102 and the camera 103 are positioned in height to have an unobstructed view of the road, despite the presence of the beacons and traffic signs 4. This is a preferred element implementation of the present invention.

Of course, the recognition of the registration number makes it possible to use the system to sanction speeding, but this application encounters regulatory, rather than technical, obstacles: therefore, only the preventive use is considered in detail in this document.

The mobile carriage 1 is now described in detail with reference to FIG. 2. It comprises a mast 100 of metal profile, with a height of 2 to 3 m and preferably of approximately 2.50 m, which is fixed on one side before 130 of a base 130. The mast 100 is composed of a lower portion 100a and an upper portion 100b, preferably connected by a hinge 120, located on the rear side of the mast 100, and by a fastening system 121, located on its front side. The upper part 100b of the mast 100 is shorter than the lower part 100a, and the difference in length is greater than the height of the base 120: this allows the folding of the mast, as shown in Figures 3A and 3B.

At the top of the mast 100, a camera 103, integrated in a waterproof and dustproof enclosure according to IP66 and equipped with a sun visor, is fixed by ball joint, in a steerable manner in elevation and in azimuth.

Near the top of the mast, on its rear side to not be an obstacle to the orientation of the camera, is also arranged an antenna 105 to provide a radio or GSM link with the variable message panel 2.

Below the camera 103, on the front side of the mast 100, is positioned a flash, particularly infrared, 102 which can be triggered at the same time as the camera to acquire an image of a vehicle in excess of speed.

Below the flash 102 is the speed detector 101, including a Doppler radar. Both the radar 101 and the flash 102 are integrated in waterproof cases IP66 and are preferably at least partially orientable.

The radar 101, the flash 102, the camera 103 and the antenna 105 arranged in height to function properly, in particular because of the obstacles that could intervene between the carriage and the portion of the road to control; for this reason they are attached to the upper part 100b of the mast.

• un ordinateur embarqué qui reçoit la valeur de la vitesse mesurée par le radar 101, la compare à un seuil prédéterminé et, si elle dépasse ce seuil, déclenche la caméra 103 et le flash 102, acquiert une image d'une voiture en excès de vitesse et, par l'intermédiaire des moyens (logiciels) d'élaboration 104 en extrait le numéro de plaque du véhicule ;
• un modem et un transmetteur radio ou GSM, pour transmettre la vitesse et le numéro de plaque de la voiture en excès de vitesse au panneau 2 ; et
• éventuellement d'autres circuits auxiliaires, tels qu'un stabilisateur de la tension d'alimentation de l'ordinateur embarqué, du modem, du transmetteur, du radar 101, du flash 102 et de la caméra 103 (12 V continu, en général) et une alarme pour prévenir des actes de vandalisme.

All electronic circuits that ensure the operation of the truck are assembled in a technical box 106, consisting of a watertight and dustproof box according to IP65. These electronic circuits include:

• an on-board computer which receives the value of the speed measured by the radar 101, compares it with a predetermined threshold and, if it exceeds this threshold, triggers the camera 103 and the flash 102, acquires an image of a car in excess of speed and, by the means (software) for producing 104 extract the plate number of the vehicle;
• a modem and a radio or GSM transmitter, for transmitting the speed and the plate number of the car in speeding to the panel 2; and
• possibly other auxiliary circuits, such as a stabilizer of the supply voltage of the on-board computer, the modem, the transmitter, the radar 101, the flash 102 and the camera 103 (12 V continuous, in general) and an alarm to prevent acts of vandalism.

The antenna 105 can be fixed to the technical box, instead of being positioned at the top of the mast.

Alternatively, the onboard computer can be integrated with the camera.

All devices and electronic devices mounted on the truck must be able to operate in a temperature range of at least -20 ° C to + 60 ° C, with a humidity level of up to 100%. Devices meeting these specifications are commercially available.

The technical box 106 is preferably provided with a socket 107 allowing the connection of a display console provided with a control keyboard 108 (for example a laptop), in order to program the on-board computer, for example. example by setting the threshold speed, the message to be displayed, the flash and camera delay, etc. If the box 106 also includes a radio receiver, it is also possible to perform the remote programming, via the antenna 105.

There is no reason to install the technical box 106 in height, on the contrary it is advantageous for the stability of the assembly to fix it to the lower part 100a of the mast, in a low position.

Above the technical box 106 is a rolling handle 109, the function of which will be explained with reference to FIG. 4.

The base 130 is essentially constituted by a watertight box 132 equipped on its right and left sides with two carrying handles 133, on its front side 131, two wheels 134 and on its side back of two feet 135. Inside the box 132 are placed batteries that power the electrical devices mounted on the carriage; it is preferably two batteries of 12 V, 100 Ah, disconnectable and rechargeable. Such batteries ensure, under normal operating conditions, a range greater than 24 hours.

The base 130 also has the function of making the carriage 1 sufficiently stable, even in the presence of wind and the movement of air induced by the passage of vehicles, despite the height of the mast 100. For this reason its dimensions may exceed the minimum necessary to contain the batteries. If the weight of the batteries proved to be insufficient to ensure the stability of the assembly, a ballast could be integrated in the base 130, in the form of a metal mass or other.

The electrical supply and signal cables which connect the different components of the carriage 1 preferably pass inside the mast 100. They must not be too tight, so as not to prevent the folding of said mast, and not not be ripped off.

Figure 3A shows the folding operation of the mast 100 to put the carriage 1 in the transport position. Firstly, it is necessary to unblock the fastening system 121 which prevents the mast 100 from folding when the system is in use and which may, for example, be constituted by a hook connected to the lower part 100a. which is introduced into a ring integrated in the upper part 100b. Once unlocked, the upper portion 100b of the mast pivots 180 ° about a horizontal axis passing through the hinge 120, until its rear side comes into contact with the rear side of the lower portion 100a. It is clear from FIG. 3A that the length of the upper portion 100b, including the camera 103 mounted on its end, must be at most equal to the length of the portion of the lower portion 100a that exceeds the base 130. In order not to constitute an obstacle to the folding of the mast, the antenna 105 may be pivotable, as shown in the figure, or telescopic. Possibly additional fastening means (not shown) may be provided to lock the upper part 100b in its folded position.

Figure 3B shows the same carriage 1 in the folded position, seen from its rear side.

Although not shown in the figures, it is possible to make the mast 100 pivoting about 90 ° about a horizontal axis with respect to the base 130, so that it can be positioned horizontally to subsequently reduce the the size of the carriage 1 during storage.

FIG. 4 shows how a single operator can easily move the carriage 1, by grasping it by the rolling handle 109, by tilting it so as to raise the feet 135 from the ground and by rolling it with the rollers 134 The base 130 has a counterweight effect that balances the carriage 1 and makes transportation easier.

If the vehicle transporting the trolley 1 from a storage warehouse to the site of use and vice versa is equipped with a ramp, only one person is sufficient to put the system in place. During its movement, the carriage 1 is preferably transported in the trailer 20 which supports the panel 2 or in the vehicle which tows said trailer.

When it is not possible to move the carriage 1 by rolling (presence of an obstacle such as a step, loading / unloading of a vehicle not equipped with a ramp, muddy or uneven ground ...) two Operators can lift the carriage 1 by grasping it by the carrying handles 133.

In both cases, the installation of the system takes less than half an hour, which is particularly advantageous in the case of short-term projects, or even a temporary limitation of speed due to an accident. In addition, in the case of sites extending over one day it is possible to dismantle the system in the evening, when no operator is no longer present on the site, to reinstall in the morning. This is particularly useful to prevent the carriage or display panel from being vandalized.

Claims (10)

1. Mobile device for detecting the speed of and identifying land vehicles, constituted by a carriage (1) on which there are arranged a camera (103) and a speed detector (101), also comprising electronic control circuits for acquiring the speed of a vehicle (3) measured by the detector (101) and, if that speed exceeds a predefined threshold, triggering the camera (103) in order to acquire an image of said vehicle (3), characterised in that it also comprises processing means (104) for extracting and recognising the registration number of the vehicle (3) from the image acquired by the camera (103), and in that the camera (103) and the speed detector (101) are mounted on a support (100) extending vertically from a base (130) which ensures the stability of the mobile device as a whole.
2. Device according to claim 1, in which the support (100) comprises a lower portion (100a) fixed to the base (130) and an upper portion (100b) connected to said lower portion (100a) by pivot means (120), so that it is able to pivot through approximately 180° about a horizontal axis.
3. Device according to claim 2, in which the camera (103) and the speed detector (101) are fixed to the upper portion (100b) of the support (100).
4. Device according to any one of the preceding claims, in which the support (100) is a mast.
5. Device according to any one of the preceding claims, in which the support (100) has a height of from 2 m to 3 m.
6. Device according to any one of the preceding claims, in which the base (130) contains batteries.
7. Device according to any one of the preceding claims, in which the base (130) comprises wheels (134) to facilitate transport of the carriage (1).
8. Device according to any one of the preceding claims, in which the support (100) comprises pivot means permitting pivoting through approximately 90° about a horizontal axis relative to the base (130), so that it can be disposed in a horizontal position.
9. Mobile system for detecting the speed of and identifying land vehicles, allowing their speed and their registration number to be displayed, comprising a mobile device (1) for detecting the speed of and identifying land vehicles according to any one of the preceding claims and at least one variable message sign (2), in which:

   the mobile device (1) for detecting the speed of and identifying land vehicles and at least one variable message sign (2) are arranged at the side of a road;

   at least one variable message sign (2) is arranged downstream, in the direction of the traffic, relative to the mobile device (1) for detecting the speed of and identifying land vehicles and is oriented in such a manner that it is easily visible from the road;

   at least one variable message sign (2) receives from the mobile device (1) for detecting the speed of and identifying land vehicles the speed and the registration number of a vehicle (3) which is travelling at a speed greater than a predefined threshold and displays them in such a manner that they can be read by the driver of said vehicle (3).
10. Mobile system for detecting the speed of and identifying land vehicles according to claim 9, in which at least one variable message sign (2) is placed on a trailer (20) which is so equipped that it is also able to hold and transport the mobile device (1) for detecting the speed of and identifying land vehicles.

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