FR2872330A1 - Method and system for monitoring vehicles in travel - Google Patents

Method and system for monitoring vehicles in travel Download PDF

Info

Publication number
FR2872330A1
FR2872330A1 FR0407027A FR0407027A FR2872330A1 FR 2872330 A1 FR2872330 A1 FR 2872330A1 FR 0407027 A FR0407027 A FR 0407027A FR 0407027 A FR0407027 A FR 0407027A FR 2872330 A1 FR2872330 A1 FR 2872330A1
Authority
FR
France
Prior art keywords
vehicle
vehicles
speed
image
radar
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
FR0407027A
Other languages
French (fr)
Other versions
FR2872330B1 (en
Inventor
Richard Leger
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
SAGEM SA
Original Assignee
SAGEM SA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by SAGEM SA filed Critical SAGEM SA
Priority to FR0407027A priority Critical patent/FR2872330B1/en
Publication of FR2872330A1 publication Critical patent/FR2872330A1/en
Application granted granted Critical
Publication of FR2872330B1 publication Critical patent/FR2872330B1/en
Application status is Expired - Fee Related legal-status Critical
Anticipated expiration legal-status Critical

Links

Classifications

    • GPHYSICS
    • G08SIGNALLING
    • G08GTRAFFIC CONTROL SYSTEMS
    • G08G1/00Traffic control systems for road vehicles
    • G08G1/01Detecting movement of traffic to be counted or controlled
    • G08G1/017Detecting movement of traffic to be counted or controlled identifying vehicles
    • G08G1/0175Detecting movement of traffic to be counted or controlled identifying vehicles by photographing vehicles, e.g. when violating traffic rules
    • GPHYSICS
    • G08SIGNALLING
    • G08GTRAFFIC CONTROL SYSTEMS
    • G08G1/00Traffic control systems for road vehicles
    • G08G1/01Detecting movement of traffic to be counted or controlled
    • G08G1/052Detecting movement of traffic to be counted or controlled with provision for determining speed or overspeed

Abstract

<P> A method of monitoring vehicles (9, 11, 12) traveling along tracks (V1, V2, V3), the speed being measured by a radar (2) from received reflection signals, for vehicles in the radar field of view, includes the steps by which the respective velocities of the vehicles in the field of view are determined; the calculated speed of each vehicle is compared to an authorized speed (Vmax). In the event of exceeding the speed authorized by one of the vehicles, an image representative of the field of view of the radar is captured and stored; from the reflection signals received by the radar, determining a number (N) of vehicles located in the field of view during the capture of the image; and process the captured image according to the determined number of vehicles. </ P>

Description

METHOD AND SYSTEM FOR MONITORING VEHICLES IN

MOVEMENT

  The present invention relates to the field of monitoring vehicles traveling on roadways.

  This monitoring generally comprises, on the one hand, the measurement of the speed of vehicles using devices such as a radar, a laser or a pair of pneumatic sensors located in the roadway. On the other hand, it includes, in the case of the demonstration of a violation relating to exceeding a maximum authorized speed, the triggering of a camera to provide at least one image of the vehicle in violation. The image or images thus obtained provide a representation o of the license plate and possibly a representation of the driver's face. They are then used for the identification of the vehicle and the driver, as well as for the establishment of the statement of offense.

  The radar is generally located at the edge of the road or at a height, so that the angle between the trajectory of the vehicles and the line of sight of the radar is of the order of 20 to 25 degrees. It measures the projection on its line of sight of the speed of the vehicle present in its field of view.

  Radars appeared, measuring not only the speed, but also the distance to the radar of a vehicle in the beam. These radars thus allow when there are several vehicles simultaneously in the beam and a vehicle has committed a speeding, to determine which of these vehicles is affected by the speeding.

  Document US Pat. No. 6,266,627 describes a technique for determining both the speed and the position of a vehicle using a pulsed Doppler monofrequency radar, that is to say, emitting pulsed signals. . Knowing the speed of propagation of the wave, we deduce from the time elapsed between the transmitted signal and the reflected signal the distance to the target.

  EP 0 933 648 discloses a traffic measurement system using a two-frequency Doppler radar. Such a type of radar emits successively signals with two adjacent frequencies. By analyzing the frequency offset between a signal transmitted by the radar and a signal received by the same radar and originating from a reflection on a vehicle of the transmitted signal, the Doppler frequency and thus the speed are determined. The distance is deduced from the phase shift between the signals reflected after successive transmissions at alternating frequencies.

  Generally, the subsequent processing of offense data, which includes captured images, calculated speeds and distances, and which are used to establish the official statement of offense, differs according to whether a vehicle or that several vehicles appear on the image. For example, some legislations do not allow the use, in an official statement of offense, of a photo representing several vehicles. However, the finding of the presence of more than one vehicle on the picture is generally carried out late. Indeed, it often takes place after an official agent has received all of the data in bulk and has reviewed the photos provided.

  The present invention aims at providing a method and a system making it possible advantageously to take advantage of the information delivered by a radar allowing the measurement of the speed and the distance of a vehicle situated in the field of view, in order to optimize the data processing of offense.

  For this purpose, according to a first aspect, the invention provides a method for monitoring vehicles moving along tracks. Velocity is measured by radar from received reflection signals for vehicles in the radar field of view. The method comprises the following steps: - the speed of vehicles located in the field of view is calculated; the calculated speed of a vehicle is compared to an authorized speed; The method further comprises the following steps in the event of an overspeed allowed by one of the vehicles: - an image representative of the field of view of the radar 30 is captured and stored to identify the vehicle; from the reflection signals received by the radar, a number of vehicles located in the field of view are determined during the capture of the image; and processing the captured image and the speed for the overtaking vehicle, according to the determined number of vehicles.

  The method according to the invention makes it possible to adapt the processing of the infringement data as soon as these data are generated, on the basis of the information available at this stage. The exploitation of the number of vehicles can be immediate to realize the adapted treatment. It is not necessary to wait for the intervention of an operator to do this.

  According to a second object, the invention proposes a system for monitoring vehicles moving along tracks, which comprises means for implementing a method according to the first aspect of the invention. Such a system thus comprises a radar measuring the speed from reflection signals received from each of the vehicles located in the field of view of the radar. It further comprises offense determination means for identifying an authorized speed override of one of the vehicles, image capturing means for capturing an image representative of the field of view and storage means for storing said image, means for determining a number of vehicles for determining the number of vehicles in the field of view during the image capture, and processing means for processing the captured image for each passing vehicle, and the speed measured associated, depending on the number of vehicles determined.

  Other features and advantages of the present invention will appear in the following description of nonlimiting exemplary embodiments, with reference to the accompanying drawings, in which: - the single figure shows an embodiment of the invention.

  In the single figure is shown a system 1 according to the invention installed on the edge of a road with three channels V1, V2, V3. It includes a 2-frequency radar Doppler effect whose technology is known. The radar 2 is for example similar to that described in document EP 0 933 648.

  The radar 2 is associated with a field of view extending around the line of sight U of the radar 2, about 5 degrees wide, which corresponds to a beam of waves emitted by a transmitting and transmitting antenna. 3. The U axis of view is at an angle of 20 to 25 degrees with the direction of channels V1, V2 and V3.

  The radar 2 comprises means for regularly switching the frequency of the signal emitted by the antenna 3, between a value f1 and a value f2. In one embodiment, for example f1 = f0 + AF / 2 and f2 = f0 OF / 2, with f0 = 24.125 GigaHertz (GHz) and AF = 800 kiloHertz (kHz). The frequency signal f1, respectively f2 is transmitted for a duration of one microsecond (1 low) before being switched to the frequency signal f2, respectively f1. Successive transmission of a signal to f1 and a signal to f2 constitutes a transmission cycle.

  Each vehicle traversing the field of view as it travels along the tracks respectively gives rise to reflected signals picked up by the antenna 3.

  The radar 2 comprises, among other things, signal processing means 4 operating on the signals emitted by the antenna 3 and on the signals received by the antenna and originating from the reflection on the vehicles crossing the field of view of the radar 2, transmitted signals. These signal processing means 4 make it possible to determine the speed of these vehicles and the distance separating them respectively from the radar 2.

  The system 1 further comprises a module 5 for determining the exceeding of a maximum authorized speed value Vmax. The speed Vmax is defined during a preliminary configuration operation of the module 5.

  The system 1 also comprises a camera 6 whose field of view is representative of the field of view of the radar 2. The field of view allows the reading of the number plates and / or the identification of the driver's face of the vehicles present in the field of view at the time of the shooting. In the embodiment, the camera 6 is a digital camera. It is equipped with a flash allowing the illumination of the scene during the shooting.

  The system 1 also comprises data storage means 7. These storage means 7 can store, for example, the data corresponding to the signals received or transmitted by the antenna 3, the image data captured by the camera 6, or calculated speeds and distances.

  The system comprises a module 8 for determining the number of vehicles present in the target field at a designated time, as well as means for constituting the offense data 10 for the subsequent establishment of the offense reports.

  The speed of a vehicle is calculated by determining in known manner the Doppler frequency generated by each vehicle present in the field of view.

  In the embodiment considered, the received signals and signals corresponding in frequency and phase to the transmitted signals, are combined in the signal processing means 4, to provide a signal o whose frequency is equal to the offset between the signal frequency. reflected and that of the transmitted signal. This Doppler frequency fD is representative of the speed of the vehicle at the origin of the reflections. Indeed it is equal to 2 * Vu / À, where Vu is the projection of the vehicle speed vector on the line of sight U and A is the wavelength of the transmitted signal. We deduce from it Vu, then the velocity V of the vehicle equal to Vu / cosa.

  The digital processing conventionally comprises a frequency transformation of the signals by Fast Fourier Transform (FFT). Each vehicle being in the field of view at a given moment therefore gives rise to a line appearing in the spatial domain, at the Doppler frequency fD representative of the speed of this vehicle.

  The signal processing means 4 are adapted to process the signals reflected by a vehicle, so as to extract, in addition to the speed, the associated distance value. This is calculated from the phase differences between reflected signals and signals emitted alternately at f1 and f2.

  Thus the distance is related to these phase differences by the following equation: 2 * d * 11A2 * 2n, where d is the distance between the radar and the% 1 * 22 vehicle, A1 and A2 are the wavelengths corresponding respectively to the signals of frequency f1 and f2, and where (PI, respectively 02 are the phase differences between the signals transmitted and received at the frequency f1, respectively f2.

  In the overshoot determination module 5, the calculated speed V for each vehicle is compared with Vmax.

  For example, with reference to the single figure, the velocity and the distance are measured for the vehicles 9, 11 and 12 respectively traveling on the tracks V1, V2 and V3 and crossing the field of view.

  In case of overtaking noted, for example for the vehicle 9, is triggered immediately taking a photo of the field of view by the camera 6 and stored in the storage means 7 a file with the digital photo taken , the speed V9 and the distance d9 calculated for the vehicle 9.

  According to the invention, during the observation of an authorized overspeed, the calculation, by the module 8, of the number of vehicles then present in the field of view of the vehicle is also triggered simultaneously with the shooting being triggered. radar 2.

  This calculation is made from the signals received by the antenna 3 of the radar and coming from the reflection on the vehicles crossing the field of view, from the signals emitted by the antenna and from the data resulting from the processing of these signals by the radar processing means 4.

  More or less complex calculations can be made according to the desired accuracy of the result.

  In one embodiment, for example, if the calculation of the speed V9 has been determined from signals reflected following the emission at a time T of a cycle (f1, f2), analyze the signals received by the antenna 3 which come from all the reflections following the emission at the instant T of this cycle (fi, f2). A spectral image is obtained which comprises respective lines at the Doppler frequencies determined for each of the vehicles having reflected this cycle of transmitted signals. From the number of lines, we deduce an estimate of the number of vehicles present at time T in the field of view. The number of vehicles is then taken equal to the number of rays.

  In another embodiment, a spectral image can be determined from signals of a cycle (f1, f2) received by the antenna 3, said cycle signals (f1, f2) being those reflected by the offending vehicle. at the time of the photo.

  In another embodiment, it is possible to reconstruct a spectral image of the field of view as it appears at the instant of taking the picture, taking into account, for the constitution of this spectral representation, the signals received by the antenna 3 and from the reflection of signals during a given number of cycles (fi, f2) preceding the instant of taking a picture.

  Once the number N of vehicles appearing on the photograph at the time of the shooting thus estimated from the signals received by the radar, it processes the file stored in memory 7 and consisting of the image, the distance and the speed measured for the infringing vehicle in the means of constituting the infringement data 10.

  If N = 1, a file is created for establishing an infringement contract using the image and speed data.

  If N is strictly greater than 1, in the case of use in a country where the law prohibits the sending to the owner of a vehicle of a statement of offense including an image where his vehicle is not not the only vehicle represented, stop processing, for example by destroying the corresponding data file.

  In another embodiment, a mapping of the channels has previously been recorded making it possible to deduce from a measured distance between a vehicle in the field of view and the radar, a corresponding channel. We have also previously established the correspondence between each channel, and the area where this path is represented in the photos.

  Thus, when constituting infringement data for an infringing vehicle by the means 10, it is determined from the distance d to the radar calculated by the signal processing means 4, for the infringing vehicle considered, the track on which he is.

  A process is then carried out to highlight the vehicle concerned by the infraction in relation to the other vehicles. For example, an automatic treatment surrounding the representation of the channel concerned by a red color and thus surrounding the vehicle in violation. In another embodiment, the zones corresponding to the representations of the tracks other than that on which the vehicle is located can be lightly grayed out.

  Then we establish a file for the establishment of the official statement of offense including the image thus treated and the speed of the vehicle found in violation.

  All the files for the establishment of the official statement of offense may be regularly transmitted to an official offense reporting center, for example through telecommunication links established between the system 1 and the center. . The identification of the vehicle will be done in this center.

  The passage of a vehicle in the field of view of the radar 2 gives rise for example to about 50 analyzes. Each analysis corresponds to a particular Doppler frequency. The result of each analysis includes the speed of the vehicle, the distance between the radar and the vehicle and possibly additional information such as the intensity of the received signal, an indicator of the quality of the analysis, the duration of the analysis etc. . In a particular embodiment of the invention, the module 5 for determining the overshoot triggers the picture by the shooting means 6 and the calculation of the number of vehicles by the module 8 at the end of a fixed number. analysis that has determined a speed greater than the maximum speed.

  Thus, a method and a system according to the invention allow automatic operations of monitoring and establishment of statements of offense adapted to the number of vehicles located a priori on the captured image. Since this number can be determined as soon as the images are taken, the treatments are optimized, for example by deleting the data comprising the image, the speed, etc. for cases for which the statements of offense can not be established when several vehicles appear on the image because of legislation or case law. Thus we reduce the number of useless data stored, and then transmitted on the communication links.

Claims (9)

    -9- CLAIMS
  1.   A method of monitoring vehicles (9, 11, 12) traveling along tracks (V1, V2, V3), the speed being measured by a radar (2) from received reflection signals, for vehicles located in a field of view of said radar, said method comprising the following steps: determining the respective speed of the vehicles in the field of view; the calculated speed of each vehicle is compared to an authorized speed (Vmax); and said method comprising the following steps in the event of an overspeed allowed by one of said vehicles: - an image representative of the field of view of the radar is captured and stored to identify the vehicle; from the reflection signals received by the radar, a number (N) of vehicles located in the field of view during the capture of the image is determined; and processing the captured image according to said determined number of vehicles.
  2.   2. Method according to claim 1, wherein if said number is strictly greater than 1, at least the captured image is deleted.
  3.   3. The method according to claim 1, wherein the distance separating them from the radar is calculated for the vehicles in the field of view of the radar, and if said number is greater than 1, elements of a finding of infringement by implementing the following steps: - it is determined on the image captured for the vehicle in excess of speed, using the distance calculated for the vehicle, the location of the representation of the vehicle concerned by the exceeding of speed ; a processing is carried out in order to highlight on the image the representation of the vehicle concerned with respect to the representation of the other vehicles appearing on the image; and the image thus treated is associated with at least the speed recorded for the vehicle, in order to establish a statement of offense element.
  4.   4. Method according to any one of the preceding claims, according to which measurements are made of the speeds and distances at determined measurement times and it is considered that a vehicle is exceeded in speed at a measurement instant when the speeds measured during the last moments of measurement and attributable to this vehicle are greater than a maximum speed value.
  5.   5. System (1) for monitoring vehicles moving along tracks (VI, V2, V3), comprising: a radar (2) measuring, from received reflection signals, the speed of vehicles located in a vehicle; field of view of said radar; - offense determination means (5) for comparing the calculated speed for each vehicle with a maximum allowable speed (Vmax) and determining an authorized overspeed; image capture means (6) for, in case of exceeding the speed allowed by one of said vehicles, capturing an image representative of the field of view to identify the vehicle and storage means (7) for storing said image; means (8) for determining a number of vehicles for determining, from the reflection signals received by the radar, the number of vehicles (N) situated in the field of view during the capture of the image; and processing means (10) for processing the captured image and the measured speed for each passing vehicle, as a function of said determined number of vehicles.
  6.   6. System (1) according to claim 5, wherein if said number (N) of vehicles located in the field of view during the image capture is strictly greater than 1, the means (10) for processing the image image and speed stop the processing of data relating to the vehicle or overtaking.
  7.   7. System (1) according to claim 5, further comprising: - distance calculating means (4) for calculating the distance separating the radar (2) from each vehicle situated in the field of view; means (10) for locating, when said number is greater than 1, determining on the image captured for a vehicle, using the distance calculated for said vehicle, locating the representation of said vehicle; - means (10) of highlighting to perform a treatment to highlight on the image compared to other vehicles shown in the image, the vehicle concerned and associate with the image thus treated at the speed recorded for the vehicle, in order to establish an element of a statement of offense.
  8.   8. System (1) according to any one of the preceding claims 5 to 7, in which the radar (2) measures the speed and distance of the vehicles in the field of view at given measurement times and in which the means (5) for determining the violation consider that a vehicle is over speeding authorized at a 12-moment of measurement, when the speeds measured during the last moments of measurement and attributable to this vehicle are greater than a speed value maximum.
  9.   9. System (1) according to any one of claims 5 to 8, wherein the radar is a dual-frequency Doppler radar.
FR0407027A 2004-06-25 2004-06-25 Method and system for monitoring vehicles in travel Expired - Fee Related FR2872330B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
FR0407027A FR2872330B1 (en) 2004-06-25 2004-06-25 Method and system for monitoring vehicles in travel

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
FR0407027A FR2872330B1 (en) 2004-06-25 2004-06-25 Method and system for monitoring vehicles in travel
AT05291339T AT420421T (en) 2004-06-25 2005-06-22 Method and system for monitoring vehicles in motion
DE200560012180 DE602005012180D1 (en) 2004-06-25 2005-06-22 Method and system for monitoring vehicles in motion
EP20050291339 EP1610279B1 (en) 2004-06-25 2005-06-22 Method and system for the surveillance of moving vehicles

Publications (2)

Publication Number Publication Date
FR2872330A1 true FR2872330A1 (en) 2005-12-30
FR2872330B1 FR2872330B1 (en) 2006-10-06

Family

ID=34946924

Family Applications (1)

Application Number Title Priority Date Filing Date
FR0407027A Expired - Fee Related FR2872330B1 (en) 2004-06-25 2004-06-25 Method and system for monitoring vehicles in travel

Country Status (4)

Country Link
EP (1) EP1610279B1 (en)
AT (1) AT420421T (en)
DE (1) DE602005012180D1 (en)
FR (1) FR2872330B1 (en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102007022373A1 (en) 2007-05-07 2008-11-13 Robot Visual Systems Gmbh Method for conclusively detecting the speed of a vehicle
CA2796110C (en) * 2010-02-08 2016-11-22 Obschestvo S Ogranichennoy Otvetstvennostiyu "Korporazija "Stroy Invest Proekt M" Method of determining speed and coordinates of vehicles with subsequent identification thereof and automatic recording of traffic offences and device for realising said method
DE102010056405A1 (en) 2010-12-23 2012-06-28 Jenoptik Robot Gmbh A method of creating an image document in which a vehicle appropriate to a radar apparatus can be identified and an image document created by this method
FR3027405B1 (en) * 2014-10-20 2016-11-18 Morpho Determining the direction of movement of a vehicle
CN105160885A (en) * 2015-07-31 2015-12-16 吉林大学 Vehicle safety driving waning device based on dangerous goods transporting vehicle identification

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2678412A1 (en) * 1991-06-28 1992-12-31 Laumonier Ateliers R Method for monitoring and, if approriate, automatically photographing objects moving on a predetermined trajectory, and device for implementing this method
DE19810302A1 (en) * 1998-03-10 1999-09-16 Wienand Hans Theo Method for measuring speed of motor vehicle
GB2389947A (en) * 2002-07-25 2003-12-24 Golden River Traffic Ltd Automatic validation of sensing devices in a road traffic monitoring system

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0935764B1 (en) 1996-04-01 2003-03-19 Gatsometer B.V. Method and apparatus for determining the speed and location of a vehicle
NL1008087C2 (en) 1998-01-22 1999-07-26 Chl Netherlands Bv Doppler radar traffic measuring system.

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2678412A1 (en) * 1991-06-28 1992-12-31 Laumonier Ateliers R Method for monitoring and, if approriate, automatically photographing objects moving on a predetermined trajectory, and device for implementing this method
DE19810302A1 (en) * 1998-03-10 1999-09-16 Wienand Hans Theo Method for measuring speed of motor vehicle
GB2389947A (en) * 2002-07-25 2003-12-24 Golden River Traffic Ltd Automatic validation of sensing devices in a road traffic monitoring system

Also Published As

Publication number Publication date
DE602005012180D1 (en) 2009-02-26
EP1610279A1 (en) 2005-12-28
EP1610279B1 (en) 2009-01-07
AT420421T (en) 2009-01-15
FR2872330B1 (en) 2006-10-06

Similar Documents

Publication Publication Date Title
US6266627B1 (en) Method and apparatus for determining the speed and location of a vehicle
EP0024430B1 (en) Vehicular anti-collision system
EP1371997B1 (en) Method for detecting stationary object on road by radar
CN101135558B (en) Vehicle anti-collision early warning method and apparatus based on machine vision
US8125372B2 (en) Driver assistance system and method for checking the plausibility of objects
US7260022B2 (en) Method and apparatus for detecting, evaluating and identifying a stationary or moving object
CN101467065B (en) Lane change assistance system for automotive
CN1808176B (en) Vehicle sensor system and process
JP3085987B2 (en) Method and radar systems for signal processing in a radar system for motor vehicles
US9079587B1 (en) Autonomous control in a dense vehicle environment
RU2175780C2 (en) Device and method for detection of disturbances of road traffic with dynamic guidance systems
JP2004301567A (en) Collision predicting apparatus
US6900754B2 (en) Signal processing method for use with scanning radar
US6035053A (en) Moving subject recognizing system for automotive vehicle
EP2820632B1 (en) System and method for multipurpose traffic detection and characterization
US8115670B2 (en) Method of verifiably detecting the speed of a vehicle
DE60213235T2 (en) Monitoring device for vehicles
US20090240432A1 (en) Vehicle-installation obstacle detection apparatus
DE102007020791B4 (en) Lane marker detection device
US6765523B2 (en) Stationary object detection method for use with scanning radar
EP1510833A1 (en) Radar
US9097801B2 (en) Obstacle detection apparatus and obstacle detection program
ES2393459T3 (en) Procedure for the detection and documentation of traffic violations at a traffic light
JP3577239B2 (en) Radar equipment
US9824277B2 (en) Pedestrian right of way monitoring and reporting system and method

Legal Events

Date Code Title Description
TP Transmission of property
TP Transmission of property
ST Notification of lapse

Effective date: 20110228