Zero Rear-End Crashes in CAS Field Test, NHTSA Says

A yearlong federal field operational test of 150 Class 8 tractor-trailers equipped with collision avoidance systems had no rear-end crashes, according to the National Highway Traffic Safety Administration.

A total of 169 drivers from seven U.S. motor carriers drove on revenue-producing routes in 2013-2014 in heavy trucks equipped with either Meritor Wabco OnGuard or the Bendix Wingman Advanced crash avoidance systems.

“In over 3 million miles of data, no rear-end crashes of the type CASes are designed to prevent were identified,” the study concluded. 

"While fleets report up to an 87% reduction in rear-end crashes and about 89% reduction in rear-end crash costs with the previous OnGuard system, our newer OnGuardActive will be a further improvement,” Meritor Wabco President Matthew Stevenson said. “We'll take lessons learned from this study to strive for the prevention of 100% of rear-end collisions moving forward."

From the data, 6,000 CAS activations were sampled, including all automatic emergency braking events and all impact alerts, the study said.



“In order to estimate system reliability, these samples were analyzed to determine whether a valid object triggered the activation and required a crash avoidance maneuver, whether a valid object triggered the activation but did not require a crash avoidance maneuver and whether an invalid object triggered the activation,” the study said.

Fred Andersky, a Bendix executive who works on customer solutions and follows government affairs, said the study showed that the collision avoidance technology has come a long way and help drivers in a variety of potential crash situations.

“I think what was really great about the test is that they really designed it to be a real-world test,” Andersky told Transport Topics. “But as we’ve always talked about collision mitigation doesn’t replace the need for safe drivers and safe-driving practices.”

Andersky said that the tests were conducted with earlier-generation systems that have since been improved with the company’s Wingman Fusion system.

“The fact that they saw good results even with the previous-generation technology, really speaks well for what the expectations can be for the next generation technology,” Andersky said. “The only negative that came out of the test is that there still is an issue with false alerts and false interventions.”

The testing systems were developed by the Virginia Tech Transportation Institute to collect continuous video of the forward roadway, video of the driver’s face, CAS activations and vehicle network data whenever the trucks were in motion. About 85,000 hours of driving and 885,000 CAS activations were collected across all activation types.

NHTSA said that fleet safety managers reported they would recommend CAS technology.

“While the CAS user experience can be improved, and some activation types were found to be less reliable than others, the results from this study suggest that the overall systems work as intended,” researchers said.