Classifications

• • G—PHYSICS
  • G08—SIGNALLING
  • G08G—TRAFFIC CONTROL SYSTEMS
  • G08G1/00—Traffic control systems for road vehicles
  • G08G1/01—Detecting movement of traffic to be counted or controlled
  • G08G1/04—Detecting movement of traffic to be counted or controlled using optical or ultrasonic detectors
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
  • B60W40/00—Estimation or calculation of non-directly measurable driving parameters for road vehicle drive control systems not related to the control of a particular sub unit, e.g. by using mathematical models
  • B60W40/02—Estimation or calculation of non-directly measurable driving parameters for road vehicle drive control systems not related to the control of a particular sub unit, e.g. by using mathematical models related to ambient conditions
  • B60W40/06—Road conditions
  • B60W40/064—Degree of grip
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
  • G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
  • G01S7/4804—Auxiliary means for detecting or identifying lidar signals or the like, e.g. laser illuminators
  • G01S7/4806—Road traffic laser detectors
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
  • G01V8/00—Prospecting or detecting by optical means
  • G01V8/10—Detecting, e.g. by using light barriers
  • G01V8/12—Detecting, e.g. by using light barriers using one transmitter and one receiver
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
  • G01V8/00—Prospecting or detecting by optical means
  • G01V8/10—Detecting, e.g. by using light barriers
  • G01V8/12—Detecting, e.g. by using light barriers using one transmitter and one receiver
  • G01V8/14—Detecting, e.g. by using light barriers using one transmitter and one receiver using reflectors
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
  • G01V8/00—Prospecting or detecting by optical means
  • G01V8/10—Detecting, e.g. by using light barriers
  • G01V8/20—Detecting, e.g. by using light barriers using multiple transmitters or receivers
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
  • G01V8/00—Prospecting or detecting by optical means
  • G01V8/10—Detecting, e.g. by using light barriers
  • G01V8/20—Detecting, e.g. by using light barriers using multiple transmitters or receivers
  • G01V8/22—Detecting, e.g. by using light barriers using multiple transmitters or receivers using reflectors
• • G—PHYSICS
  • G08—SIGNALLING
  • G08G—TRAFFIC CONTROL SYSTEMS
  • G08G1/00—Traffic control systems for road vehicles
  • G08G1/01—Detecting movement of traffic to be counted or controlled
  • G08G1/0104—Measuring and analyzing of parameters relative to traffic conditions
  • G08G1/0108—Measuring and analyzing of parameters relative to traffic conditions based on the source of data
  • G08G1/0112—Measuring and analyzing of parameters relative to traffic conditions based on the source of data from the vehicle, e.g. floating car data [FCD]
• • G—PHYSICS
  • G08—SIGNALLING
  • G08G—TRAFFIC CONTROL SYSTEMS
  • G08G1/00—Traffic control systems for road vehicles
  • G08G1/01—Detecting movement of traffic to be counted or controlled
  • G08G1/0104—Measuring and analyzing of parameters relative to traffic conditions
  • G08G1/0108—Measuring and analyzing of parameters relative to traffic conditions based on the source of data
  • G08G1/0116—Measuring and analyzing of parameters relative to traffic conditions based on the source of data from roadside infrastructure, e.g. beacons
• • G—PHYSICS
  • G08—SIGNALLING
  • G08G—TRAFFIC CONTROL SYSTEMS
  • G08G1/00—Traffic control systems for road vehicles
  • G08G1/01—Detecting movement of traffic to be counted or controlled
  • G08G1/0104—Measuring and analyzing of parameters relative to traffic conditions
  • G08G1/0137—Measuring and analyzing of parameters relative to traffic conditions for specific applications
  • G08G1/0141—Measuring and analyzing of parameters relative to traffic conditions for specific applications for traffic information dissemination
• • G—PHYSICS
  • G08—SIGNALLING
  • G08G—TRAFFIC CONTROL SYSTEMS
  • G08G1/00—Traffic control systems for road vehicles
  • G08G1/01—Detecting movement of traffic to be counted or controlled
  • G08G1/048—Detecting movement of traffic to be counted or controlled with provision for compensation of environmental or other condition, e.g. snow, vehicle stopped at detector
• • G—PHYSICS
  • G08—SIGNALLING
  • G08G—TRAFFIC CONTROL SYSTEMS
  • G08G1/00—Traffic control systems for road vehicles
  • G08G1/07—Controlling traffic signals
• • G—PHYSICS
  • G08—SIGNALLING
  • G08G—TRAFFIC CONTROL SYSTEMS
  • G08G1/00—Traffic control systems for road vehicles
  • G08G1/09—Arrangements for giving variable traffic instructions
  • G08G1/091—Traffic information broadcasting

Definitions

• the present invention is a device for automatically adapting the authorized speed limits on road according to the traffic conditions and to transmit the information to a receiver.
• the receiver can display information on the dashboard of a vehicle or on variable display signboards, or even transmit it to one or more speed cameras.
• the invention also relates to a device for the detection of water on the road, in particular by the use of a light beam transformed by refraction and absorption phenomena.
• the device is installed on the road; according to another embodiment, it is installed on a vehicle.
• traffic conditions are degraded. The rain hinders the driver's vision, the road becomes wet or even wet, by reducing the grip of the wheels, increases the braking distances and can even lead to a loss of control of the vehicle.
• the Highway Code provides for a reduction in the speed limits allowed during rainy weather. In France for example, the speed limit is reduced from 130 km / h to 110 km / h on
• motorways from 110 km / h to 100 km / h on expressways, from 90 km / h to 80 km / h on non-urban roads.
• infrared detection systems are used to determine the road surface conditions and is able to determine the difference between snow, ice and dry or wet, etc.
• An infrared beam emitter is mounted on a cross-piece overlooking the road surface from a central pillar.
• a sensor is used to detect the reflection directly from the surface, one for incident light and one for monitoring the surface temperature.
• An ambient temperature sensor is coupled to the processing unit.
• the reflector outputs are compared to reference values to identify the different conditions of the road surface.
• the device according to the invention is based on the use of a light beam transformed by refraction and absorption phenomena for the detection of water in the road.
• the vehicle is used as a witness of this rainy weather. Indeed, the wheels of a vehicle passing on a wet pavement generate splashes behind them. This shower of water can only occur if the road is really wet and not just wet as with condensation. Its existence is irrefutable proof of the notion of "rainy weather" and can not be challenged by the courts. Its detection makes it possible to automate the maximum speed reduction allowed on fixed radars, without human intervention. Due to its lack of sensitivity, this criterion is favorable to the driver because the short rainy weather will not be detected. There is therefore no possibility of false positives and the offender will not be able to invoke a system failure. In addition, the legislator will have full latitude to adjust the sensitivity of the device to retain only more water sprays or smaller.
• the device according to the invention makes it possible to provide a solution to the problem of compliance with speed limits in all circumstances.
• the device according to the invention uses the passage of the wheels which raises behind them, when the road is wet, splashing or even shower of water.
• the splashes, the sheaves consist of more or less large drops of water and in more or less abundant quantity.
• a light beam, visible or not, through them will undergo, depending on its wavelength, several phenomena that can also accumulate. These are the phenomena of refraction and absorption.
• we will speak of a light beam any type of focused electromagnetic beam for example of the laser type or using an LED-lens system or any other system well known to those skilled in the art.
• the device for the detection of water in the road uses a light beam and is installed on the road.
• a focused light beam is emitted by a light emitter on one side of the road and received by a sensitive surface on the other side serving as a light receiver.
• the light beam passes a few centimeters above the road to be able to meet any splashing in the immediate back of the wheels.
• a reflective system consisting of a single mirror or a retro-reflector may be arranged on the other side of the road and returns the radius of the road. transmitter to the receiver.
• the light beam will be abruptly interrupted by the flanks of the wheel and then its passage is again as brutally possible.
• the microcomputer connected to the sensitive surface of the receiver will record the data received therefrom and virtually construct a curve in a marker having the time for abscissa and the intensity of the received electrical signal or the amount of illuminated pixels for ordinate.
• the curve thus obtained will be of "square" type.
• the light beam In a sufficiently wet weather to generate splashes, the light beam will be abruptly interrupted by the flanks of the wheel, then its
• the device can be connected directly to one or more mobile radars and send them by wire link, radio or other, a signal indicating the "rainy weather” so that they adjust accordingly.
• the light receiver is placed at the bottom of an opaque tube to the lengths of waves used and perpendicular to its axis.
• the diameter and the length of the tube are designed to allow the light beam, normal or degraded, to reach the receiver but limit the parasitic radiation not coming from the transmitter.
• the inside of the tube is covered with a substance that absorbs unwanted rays in order to prevent their reflections to the bottom of the tube, for example matt black in the case of the use of wavelengths in the visible spectrum .
• the tube is obviously perfectly directed to the transmitter so that the beam reaches the receiver.
• the light beam is emitted with a frequency and amplitude modulation known only to the receiver
• pattern in order to be able to discriminate parasitic rays. This pattern thus makes it possible to avoid treating parasitic rays.
• the device is insensitive to the emission impairments of the light beam (dirt, drop in emission intensity for example) because what characterizes the wet road is not an overall decrease in the received signal, but a very precise change in the shape of the curve just after the passage of the wheel.
• the measured value serves as a reference and is found immediately (dry road) or some time (wet road) after the passage of the wheel. The gradual decline of this absolute value will however trigger a repair of the device (cleaning of the elements, control of the quality of the transmitter, etc.)
• the emitted light beam must be focused to be sufficiently
• the light beam may be in a visible or invisible radiation spectrum. Although focusing by lens system can be used, the laser is the most suitable beam. An infrared laser will probably be preferred because it does not bother the motorist and is easily available and cheap.
• the device for detecting water on the road by the use of a light beam is attached to the vehicle.
• the emitter of the light beam is disposed on one side of the wheel and the receiver on the other side, the two parts being fixed
• the receiver consists of a sensitive surface and a microcomputer that interprets the data transmitted by the sensitive surface.
• the sensitive surface may consist of one or a few photoreceptors, for example photovoltaic cells distributed over a small area.
• the light beam is directed precisely at the receiver and the diameter of the light beam is at least equal to the diameter of the sensitive surface of the receiver. This type of receiver will record the intensity of the signal produced by the photoreceptors. When the light beam passes through a water projection zone, the light beam by refraction and absorption phenomena will see part of its photons deviated or absorbed and these will therefore no longer reach the sensitive surface of the receiver.
• the receiver By dry road the receiver thus records a nominal intensity which is maximum and which will drop by wet road.
• the receiver When the receiver consists of many photoreceptors placed on a surface whose diameter is much greater than that of the light beam, the device will record the amount of photoreceptors excited by the light.
• the light beam On a dry road or when the vehicle is stationary, the light beam is intense and focused and the nominal amount of excited photoreceptors is minimal.
• the light beam passes through a zone of water splashes, the refraction phenomena will deflect part of its photons. The diameter of the light beam will then increase exciting more photoreceptors.
• the signal recorded in this type of receiver then increases in rainy weather.
• the emitter of the light beam is then fixed under the vehicle and is directed towards the ground behind the wheels.
• the light receiver may be a camera attached under the vehicle that records the image formed by the beam on the ground.
• This camera consists of a receiving surface comprising one or more photoelectric sensors (photo diode) and an optical system focusing the image on the sensitive surface.
• photoelectric sensors photo diode
• the image will be modified.
• the image is then processed by a microcomputer using for example image processing algorithms, which will notably focus on highlighting changes in sharpness, shape, surface and light intensity of the image. This change will depend on the amount of water projected.
• the refraction will cause an increase in the surface of the image or its displacement by the refraction phenomena compared to the reference image recorded on dry road or when the vehicle is stopped.
• An absorption phenomenon if the length Wavelength of the light beam corresponds to a water absorption band will cause a decrease in the luminous intensity of the recorded image.
• the light beam is emitted with a frequency modulation and known amplitude of the single receiver (pattern), in order to be able to discriminate parasitic signals.
• This pattern makes it possible to avoid dealing with spurious images.
• To form the reference image it is possible to
• the image used as reference varies in time and depending on weather conditions because of this soiling. It is optionally provided a device for cleaning these sensitive surfaces for example through the use of materials with "self-cleaning" qualities and or pressurized spraying devices or ice wiper type or other devices well known in the art. skilled in the art.
• the road being very heterogeneous, another configuration uses two light beams from two transmitters or one whose primary light beam is separated by an optical device, composed for example of mirrors and prisms, into two identical secondary beams.
• a beam is directed behind the wheel to highlight any projections while the other is directed at a distance and rather laterally to the wheel or before the passage of the wheel for reference.
• Two images recorded by one or two cameras are formed. Note that on dry road or at a standstill, the two images are virtually identical. When the vehicle rolls and its wheels raise water droplets on wet roads, the two images are different, depending on the amount of water sent by the wheels. This differentiation signifies the wet road condition.
• the device may also be supplemented with a radio transmitter which sends the signal "rainy weather" to one or more fixed receivers placed on the route or mobile fixed to other vehicles not equipped to inform other vehicles
• variable message display panels for "rainy weather” conditions.
• Figure 1 shows a front view of the fixed device in situation
• Figure 2 shows a profile view with visualization of the shower of water behind the wheels
• Figure 3 shows the characteristic curve of a dry road
• Figure 4 shows the characteristic curve of a wet road for intensity measurement.
• Figure 5 shows the characteristic curve of a wet road for a surface measurement of the spot.
• Figure 6 represents the vehicle of profile with the emitter of the light beam arranged on one side of the wheel and the receiver on the other side
• Figure 7 represents the vehicle seen from below with the emitter of the light beam arranged on one side of the wheel and the receiver on the other side
• Figure 8 represents the vehicle in profile with the device attached under the vehicle with a transmitter and two cameras
• Figure 9 represents the vehicle seen from below with the device fixed under the vehicle with a transmitter and two cameras
• Figure 10 represents the vehicle profile with the device attached under the vehicle with two transmitters and two cameras
• Figure 11 represents the vehicle seen from below with the device fixed under the vehicle with two transmitters and two cameras
• FIG. 1 shows a view of the device in situ with the vehicle (1) from the front, perpendicular to the light beam (7) with its wheels (2) on the road (3), the light beam (7) passing through it at a height a few centimeters above the road (3) and parallel to its surface.
• the height is defined so that the light beam (7) passes under the underbody of the vehicles and under the mudguard devices and is not impeded by surface defects of the vehicle.
• the light beam (7) is emitted by the transmitter (5) crosses over the road (3) and then passes through the tube (6) along its length and touches the sensitive surface (8) of the receiver (R).
• Figure 2 shows in profile the light beam (7) pass through the shower of water (4) caused by the passage of the wheel (2).
• the receiver (R) consists of an opaque tube (6) at the bottom of which is placed perpendicularly to the axis of the tube (6), a sensitive surface (8).
• the tube (6) may be, for example, an opaque plastic material of the PVC type, the internal wall of which is covered with a substance preventing the reflection of parasitic rays not parallel to the axis of the tube (6), for example a matte black paint. .
• the diameter and the length of this tube (6) are defined by those skilled in the art to limit the parasitic rays.
• the sensitive surface (8) consists of a photovoltaic system for example CCD sensors.
• the senor functions as a photovoltaic cell which will transform the quantity of photons received in the normal target area of the light beam (7) on the sensitive surface (8) into one an electrical signal whose intensity will be proportional to the quantity of photons received.
• the receiver In the case where the size of the surface of the spot produced by the light beam (7) on the sensitive surface (8) is measured, the receiver consists of multiple sensors, type CCD for example forming pixels. The quantity of pixels activated by the light beam (7) is proportional to the surface of the spot and thus makes it possible to know the surface of the spot.
• These electrical signals are then processed by a microcomputer and a "rain time" signal is transmitted by wire or electromagnetic waves to the fixed radar, which will then adjust its maximum allowed limit.
• a hygrometer can be coupled to this device. Only the presence of humidity in the air (atmospheric hygrometer) or on the road (surface hygrometer) triggers the commissioning of the device.
• the microcomputer will construct a square type signal ( Figure 3) when a wheel passes in front of the light beam (7).
• Figure 3 the quantity of electromagnetic energy received or the quantity of photoreceptors activated by the light beam (7) and on the abscissa the time in milliseconds, for example.
• FIG. 4 shows the curve produced in the case where the quantity of photons received by the sensitive surface (8) with this intensity in ordinates and the time in abscissa.
• Figure 5 shows the case where the receiver (R) measures the surface of the spot produced by the light beam (7) on the sensitive surface (8), this value being used as an ordinate.
• a light beam emitter (5) is fixed under the vehicle (1) behind the wheel (2) by example in the wheel arch at the level of the fender on one side of the wheel (2). It is possible to use one or more wheels (2).
• a receiver (R) consisting of
• the transmitter (5) sends a light beam (7) with an emitted electromagnetic pattern with a known frequency and amplitude modulation the only receiver (pattem), in order to be able to discriminate parasitic signals.
• This pattern makes it possible to avoid processing parasitic lights on the receiver (R) and thus to limit parasitic phenomena.
• the receiver (R) registers a signal with a nominal intensity on the receiving surface or a nominal surface when the receiver focuses on recording the surface excited by the light beam (7).
• FIGS 10 and 11 show a system in which a single transmitter (5) directs its light beam (7) on the roadway which forms an image (18) behind the wheel (2).
• a camera (19) records the image (18) and sends it to a microcomputer equipped with image processing algorithms and compares it to a reference image. This reference image is obtained by filming the image (18) obtained when the vehicle (1) is stopped. Without changing anything in the operation, one skilled in the art could prefer an architecture with two transmitters (5, 20) each producing an identical light beam.
• Figures 8 and 9 show a system with a transmitter (5) and two cameras (19, 23) filming at the same time the two images (18,22) produced by the light beams (24, 25) on the roadway.
• the primary light beam (7) produces two identical secondary light beams (24, 25) by passing through an optical device (26).
• This is for example composed of a mirror which directs the beam (7) towards the roadway and a prism which separates the primary beam (7) into two secondary beams (24, 25).
• the secondary beam (24) measurement is directed on the pavement just behind the wheel (2).
• the reference secondary beam (25) is directed on the roadway laterally to the wheel (2) so as to be almost protected from the water projections (4) raised by the wheel (2) when the road is wet.
• a camera (23) records the image (22) of the secondary reference beam (25) on the roadway while the other camera (19) records the image (18) of the secondary measurement beam (24).
• the images (18, 22) are then sent to a microcomputer equipped with image processing algorithms that compare them.
• a difference between the reference image (22) and the measurement image (18) signifies the existence of water projections behind the wheel (2) and highlights the wet state of the road.
• Lens cleaning devices of the one or more cameras (19, 23) or the receiver (R) and the transmitter (s) (5, 20) are provided in order to limit soiling which disturbs the transmission of the light rays. They consist for example of pressurized sprinkler system or ice wiper blades for example.
• self-cleaning glasses by depositing on them, for example, a photocatalytic layer based on titanium dioxide may also be envisaged.
• the device according to the invention is connected by wire or radio to the computer or computer of the vehicle (2) which can then send an alert message to the driver or directly adjust the speed of the vehicle (2) in view of the conditions of degraded traffic.
• the device sends the information to the calculator.
• the calculator translates this information into the maximum speed allowed under these degraded conditions and sends this value to one or more digital billboards.
• the panel or panels then show the drivers the maximum speed allowed in these degraded conditions.
• the device according to the invention can be used in a set of deterioration detectors driving conditions connected via a computer to one or more variable display speed limitation panels (LED or LCD type by example) and whose display is changeable remotely, the latter or these indicating in real time the authorized speed limit adapted to traffic conditions.
• the set of detectors for impairment of driving conditions comprises one or more detectors arranged within one or more housings.
• the set of conduct condition deterioration detectors- is composed of all or some of these centralized detection elements within a single detection box or in several systems and connected to a computer that centralizes the information collected by each of the detection systems and sends the signal adapted to the degradation observed to the display panels and radar or billboards which themselves transmit it to radar.
• a complete system is composed for example of a detector of "rainy weather", a detector of rain, of a detector of wet road or icy, a detector of the number of vehicles per hour, a detector of decline of visibility, a detector of pollution
• the calculator can also send information simultaneously to billboards and radars.
• the calculator or billboard or radar sends the information to the regional or national central office to inform the authorities about the real-time traffic situation.
• the links between the detectors, the computer, the panel, the radar and the central unit are made via a wired system or by electromagnetic waves.
• the communication system according to the LoRaWAN protocol Long Range Wide-Area Network
• LoRaWAN protocol Long Range Wide-Area Network
• the device according to the invention is particularly intended for road safety.

Landscapes

• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Chemical & Material Sciences (AREA)
• Analytical Chemistry (AREA)
• Life Sciences & Earth Sciences (AREA)
• General Life Sciences & Earth Sciences (AREA)
• Geophysics (AREA)
• Engineering & Computer Science (AREA)
• Optics & Photonics (AREA)
• Automation & Control Theory (AREA)
• Transportation (AREA)
• Mechanical Engineering (AREA)
• Multimedia (AREA)
• Mathematical Physics (AREA)
• Computer Networks & Wireless Communication (AREA)
• Radar, Positioning & Navigation (AREA)
• Remote Sensing (AREA)
• Traffic Control Systems (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=61972076

Family Applications (1)

Country Status (8)

Families Citing this family (3)

Family Cites Families (6)

• 2017
  • 2017-04-11 RO ROA201700216A patent/RO132860B1/ro unknown
• 2018
  • 2018-04-10 EP EP18717508.8A patent/EP3610473A1/de not_active Withdrawn
  • 2018-04-10 JP JP2019554698A patent/JP2020516998A/ja active Pending
  • 2018-04-10 CN CN201880021330.5A patent/CN110520914A/zh active Pending
  • 2018-04-10 CA CA3056988A patent/CA3056988A1/en not_active Abandoned
  • 2018-04-10 WO PCT/EP2018/025105 patent/WO2018188811A1/fr unknown
  • 2018-04-10 KR KR1020197028589A patent/KR20190139858A/ko not_active Application Discontinuation
  • 2018-04-10 US US16/498,388 patent/US20210110712A1/en not_active Abandoned

Also Published As

Similar Documents

Legal Events