Leddar

LEDDAR (Light-Emitting Diode Detection And Ranging) is a proprietary technology owned by LeddarTech which combines LED lighting and 3D sensing to illuminate an environment, then detect and measure the distance of a wide range of objects in the zone of illumination through the analysis of the echo back signal of light reflected via backscattering.

Technology

LEDDAR technology integrates an LED lighting source and driver, optical detectors, processing unit and interface for the combination of illumination and sensing purposes. LED lighting can be either in the visible (white or specific color) or infrared spectrum, illuminating all objects in a specific environment. Optical multiple field of view detectors receive the light reflected via backscattering, then a processing unit digitizes and analyzes the echo back signal to produce a data output associated with a 3D position of objects in the detected area. LEDDAR’s detection is based on the time-of-flight of light principle, or phase shift method. Analyzing the return waveforms generated by all reflective surfaces within the entire light span emitted by LED lighting, the processing unit makes it possible to determine a specific signature from hard objects such as vehicles, pedestrians, cyclists and walls, and from soft objects such as fog, snow, rain and mist.

The data is compiled thousands of times per second, providing up to a few hundred frames per second and offering accurate and reliable information even in adverse weather and lighting conditions.

The multi-channel sensor also provides lateral discrimination of detected objects and this feature, with 3D measurements, provides the basis for object tracking.[1][2]

Applications

Smart Lighting

LEDDAR can be used in Smart Lighting applications. The LED lighting sensors measure the time to return light for mapping an environment with low resolution and detect animate or inanimate objects so as to provide real time data and detect any activity in a specific area, for energy saving, occupancy sensing and security applications.[3]

Advanced Driver Assistance Systems (ADAS)

ADAS refers to systems and technologies integrating sensors all around the vehicle and actuators that support the driving process in order to increase safety and comfort. The adoption of LED lighting in automotive[4][5] and the trend to integrate ADAS technology in mass market vehicles[6][7] are two enablers for LEDDAR technologies combining the lighting function and detection capabilities in such ADAS applications as a Blind spot (vehicle) detection system, Intelligent Parking Assist System and precrash system.[8]

Traffic management

LEDDAR has been used as a non-intrusive sensor for traffic light control and coordination at intersections to ensure traffic mobility and fluidity, minimizing delays to road users (drivers, cyclists and pedestrians). The LEDDAR sensor can be mounted directly to current traffic infrastructure with an onboard image processor, making possible the remote alignment and providing the capability to transmit video images back to the traffic operations center.[9] As an example, the City of Davis installed several LEDDAR sensors and was able to detect cars and bikes in more situations[10] in any kind of weather, notably fog, high wind and heavy rains.[11] The LEDDAR sensor is also used for traffic data collection.

Speed and red light enforcement

LEDDAR has also been used as a sensor for traffic detection in speed limit enforcement systems and red light enforcement systems. A LEDDAR sensor has been used as the entry/exit point detector for the average speed detection system deployed in France.[12][13][14]

Electronic Toll Collection

LEDDAR is also used for Electronic Toll Collection applications. The sensor generates an infrared light-curtain to provide 3D information to detect vehicles of all dimensions in order to generate vehicle profiles for automated vehicle classification. The recorded shape of the vehicle, which can help distinguish cars, trucks and trailers, is used to determine the charge rate related to the specific class of vehicle passing through the toll facility.[15]

Other uses

LEDDAR can also be used in industrial applications, notably to determine the level of a substance in a container (Level sensor)[16] and for object detection in an open aisle in mobile shelving systems.[17]

See also

Time of flight

Rangefinder

Laser rangefinder

LIDAR

Sonar

Radar

References

  1. ↑ US Patent 7855376 - Lighting system and method for illuminating and detecting object
  2. ↑ US Patent 8242476 - LED object detection system and method combining complete reflection traces from individual narrow field-of-view channels
  3. ↑ SMART LIGHTING SYSTEMS – ULTIMATE LIGHTING, The Smart Lighting Engineering Research Center, 2012
  4. ↑ Lighting the way: Perspectives on the global lighting market, McKinsey, 2011
  5. ↑ LED forward lighting market to almost double by 2020
  6. ↑ ADAS Market Trends: Kickstarting the mass market for ADAS - a review of the key market drivers 2011
  7. ↑ ADAS Vehicle Technologies Ride Up to Solid 60 Percent Revenue Growth in 2011
  8. ↑ Shining light on ADAS, Vision Zero International, June 2009
  9. ↑
  10. ↑ LEDdar, Daviswiki
  11. ↑
  12. ↑ Average Speed Detection System Launches At Intertraffic
  13. ↑ France deploys its first average speed cameras
  14. ↑ http://fr.wikipedia.org/wiki/Radar tronçon en France
  15. ↑ LeddarTech unveiling Leddar side-tec, a 3D detection system
  16. ↑ US patent 8159660 - Optical level measurement device and method
  17. ↑ WO/2012/011037 - 3D OPTICAL DETECTION SYSTEM AND METHOD FOR A MOBILE STORAGE SYSTEM

External links