Test Track Lateral Stability Performance of Motorcoaches Equipped with Electronic Stability Control Systems.

摘要

The research detailed in this report supports The Motorcoach Safety Action Plan released by the Department of Transportation (DOT) on November 16, 2009 and ongoing safety research by DOT's National Highway Traffic Safety Administration (NHTSA). Electronic stability control (ESC), a crash avoidance technology was identified in the plan as a potential motorcoach safety enhancement designed to improve stability in rollover and loss-of-control scenarios. The research described in this report was performed by the NHTSAs Vehicle Research and Test Center (VRTC) from 2008-2010. The goals of this testing were to evaluate motorcoach lateral stability and understand how motorcoach ESC systems modify the handling and stability characteristics on the test track. Measures of performance from preceding commercial vehicle research with truck tractors were evaluated to determine their potential use in assessing lateral stability and responsiveness of motorcoaches equipped with stability control systems. Performance maneuvers evaluated were the sine with dwell, half-sine with dwell, ramp with dwell, ramp steer maneuver, slowly increasing steer maneuver, and the constant radius maneuver. These test track maneuvers are representative of lane changes, obstacle avoidance, or negotiating-a-curve crash scenarios. Using these maneuvers, three commercial Class 8 (air braked) motorcoaches were equipped with safety outriggers and tested with and without ESC enabled. The motorcoaches and ESC systems were evaluated lightly loaded and at a loaded weight with simulated passengers. Maneuvers were performed on high friction dry asphalt and reduced friction Jennite test surfaces. Using data from this test track research, several measures of performance were analyzed that have merit for use in evaluating the lateral stability performance of commercial vehicles.