Crash Warning System Tested

A laser-based ranging system has been developed to assess the performance of automobile collision warning systems. The technology could also be used to create new systems that can warn drivers of multiple road hazards simultaneously.

Engineers at the National Institute of Standards and Technology (NIST) in Gaithersburg developed and tested the technology, which will be used by researchers in industry and at the US Department of Transportation (DOT) to accelerate the development of safety systems that alert drivers to multiple and sometimes virtually simultaneous potential crash hazards from forward or side collisions as well as from running off the road.

A truck cab is equipped with NIST's laser-based ranging system for tests of collision warning systems. (Photo: NIST)

Preliminary tests of prototype collision detection systems using with the NIST technology have revealed both potential benefits and areas that need improvement.

According to DOT, of the 3.6 million rear-end, road departure and lane change crashes that occur each year in the US, 27,500 result in one or more fatalities -- about three-quarters of the nation’s yearly auto-related deaths. DOT estimates that widespread deployment of advanced integrated driver assistance systems may reduce such collisions by 48 percent. The department has formed a partnership with the automobile industry called the Integrated Vehicle-Based Safety Systems (IVBSS) initiative to hasten deployment of advanced warning systems in US vehicles.

To evaluate the performance of crash warning systems, which generally use radar, researchers needed an accurate measurement tool based on entirely different principles. NIST researchers developed an independent measurement system (IMS) consisting of a camera and microphone in the cab to detect the driver warning, a suite of calibrated cameras to measure the distance to lane boundaries and laser scanners to measure the distance to obstacles forward and to the side of the vehicle. The system can be mounted on cars or trucks with trailers and requires no modifications or connections to the warning system being tested. It can detect an object to within 33 inches at a distance of 197 feet and speeds up to 56 mph.

NIST used the IMS to evaluate the performance of two systems built by IVBSS industry partners for a light vehicle and a heavy truck. Researchers collected data in representative crash-imminent driving scenarios in which a crash warning should be issued as well as scenarios that might cause a system to issue a false alarm. Both systems passed most of the more than 30 tests conducted this fall in East Liberty, Ohio, and Dundee, Mich.

However, the IMS revealed some warning system problems in detecting whether forward vehicles were in lane or out-of-lane on curves or during lane changes. The IMS also measured significant warning delays that resulted in test failures. Such problems are common in automotive crash warning systems that must operate in real-time, at highway speeds, and use multiple low-cost sensors to measure complex 3-D scenes.

DOT is currently analyzing the IMS data and deciding if the system is worthwhile to pursue.The next step would call for the IVBSS to equip approximately 20 automobiles and 10 trucks with the warning systems. Volunteer motorists and truckers would use the vehicles on highways for a month, after which the DOT would analyze the data to estimate what the benefit would be if the system is deployed in most vehicles.

For more information, visit: www.its.dot.gov/ivbss