Bendix Supports Choice Of ESC At NHTSA Public Hearing For Proposed Stability Requirement
ELYRIA, OH… Bendix Commercial Vehicle Systems LLC endorsed the choice of full-stability technology by the National Highway Traffic Safety Administration (NHTSA) in the agency’s recent Notice of Proposed Rulemaking (NPRM) that would require stability technology for commercial vehicles. Fred Andersky, Bendix director of government and industry affairs, presented comments on the company’s behalf at NHTSA’s public hearing for the NPRM held at the Department of Transportation headquarters in Washington, D.C.
The NPRM, published on May 23, would require full-stability technology, known as Electronic Stability Control (ESC), on truck tractors and certain buses with a gross vehicle weight rating of greater than 11,793 kilograms (26,000 pounds).
In his presentation, Andersky compared the performance and effectiveness of ESC and roll-only – or Roll Stability Control (RSC) – stability systems. Bendix develops and supplies full-stability systems, which it markets as Bendix® ESP® Electronic Stability Program, and roll-only systems to commercial vehicle manufacturers as part of a full suite of active and supportive safety technologies.
“As a business, our preference is to let the market decide technology choices. It is our position, however, that if a stability control regulation is forthcoming, ESC is the best technology choice,” Andersky said. “It is the one stability technology that, in our expert opinion, delivers the power and performance needed to help commercial vehicle drivers mitigate both rollover and loss-of-control situations.”
Andersky said two key factors – information and interventions – support the Bendix recommendation for ESC over RSC. He added, “Extensive research and development – along with over seven years of solid customer experience – reinforces our position.”
Stability systems use sensors to provide information about vehicle behavior and driver intent. Full-stability systems employ two more sensors than the typical roll-only system. These extra sensors, Andersky said, help the stability system assess a potential crash situation sooner, which can lead to an earlier intervention.
If an intervention is required, the ESC system can respond by providing more braking power than a typical RSC system. The additional braking power is critical for both roll and directional stability, Andersky said. Full-stability systems achieve more powerful brake interventions by involving the steer, drive, and trailer axles, whereas roll-only systems typically apply the brakes only on the drive and trailer axles.
Citing “Road Map for the Future: Making the Case for Full-Stability,” a white paper that Bendix published in 2008, Andersky said that slowing the vehicle quickly helps mitigate rollovers faster, while slowing and redirecting can help the driver maneuver in loss-of-control situations. Both actions need support from the steer axle. He noted that with the recently enacted legislation requiring a 30 percent reduction in stopping distance, more braking power is now concentrated on the steer axle.
Andersky also addressed the effectiveness of ESC and roll-only systems. He pointed to NHTSA’s Preliminary Regulatory Impact Analysis, which indicated a 6 to 7 percent higher overall effectiveness for ESC over roll-only systems. The agency’s conclusions were drawn from studies that reviewed crashes where stability technology might have helped mitigate the situation, relying significantly on cases from the Federal Motor Carrier Safety Administration’s (FMCSA) “Large Truck Crash Causation Study” (LTCCS) published in 2006.
“While we agree with the general conclusion drawn from the NHTSA studies – that ESC is more effective than RSC – we believe the results are actually conservative,” Andersky said.
Drawing on more than 20 years of experience in commercial vehicle dynamics and stability control systems, Bendix updated its own original analysis of the LTCCS cases regarding the performance of ESC in both rollover and loss-of-control situations. The Bendix analysis, Andersky said, resulted in a significantly greater difference – 31 percent – between ESC and RSC effectiveness. Bendix provided its findings to NHTSA.
“A wider difference in effectiveness – using the cost estimates provided in the Preliminary Regulatory Impact Analysis, which accompanied the rulemaking – would likely result in a net benefit greater than originally estimated in the NPRM,” Andersky said. “We will explore this position further in our formal comments to the docket.”
Bendix was the first North American brake system manufacturer to make full-stability solutions widely available for the commercial vehicle market, introducing Bendix® ESP® in early 2005. The proven nature and wide availability of full-stability technology is a benefit to the industry, Andersky said. He noted that ESC is available from all truck manufacturers.
Andersky emphasized the importance of drivers as an integral part of the safety equation. A CDL holder himself, Andersky said he understands that crashes can happen in an instant – to even the best drivers. It’s in those moments, he said, that stability technology can make the difference between a crash and a close call, with Bendix believing that ESC can aid drivers in more instances than RSC.
“ESC – as the technology of choice for this rulemaking – will save more lives, reduce more injuries, and mitigate more crash situations than RSC,” Andersky said.
Bendix will release a complete response to NHTSA regarding the company’s position on stability technology in the time frame for comments provided.