On September 18, 2006 the National Highway Traffic Safety Administration (NHTSA) announced a proposal that would require installation of electronic stability control (ESC) as standard equipment on all light vehicles by model year 2012 [1]. The decision to mandate ESC required that NHTSA develop an ESC compliance test and evaluation criteria. This paper describes the proposed test maneuver and discusses the methods proposed to interpret the data generated by that maneuver.

NHTSA’s ESC proposed compliance test maneuver, the Sine with Dwell, was used to produce all the data described in this paper. This maneuver is based on a single cycle, 0.7 Hz steering input, with a 500 ms pause between the third and fourth quarter cycles. Output from Sine with Dwell tests is used to evaluate both the lateral stability and responsiveness of ESCequipped light vehicles.

NHTSA proposes acceptable lateral stability be assessed with two performance criteria, intended to encourage yaw rate to decay in a controlled manner. These criteria compare the yaw rates measured 1.0 and 1.75 seconds after completion of the maneuver’s steering inputs to the first local yaw rate peak produced after the second steering reversal. These “yaw rate ratios” must be less than or equal to 35 and 20 percent, respectively.

To ensure that a balance between lateral stability and the ability of the vehicle to effectively respond to the driver’s inputs is maintained, NHTSA has proposed a responsiveness metric supplement that used to assess lateral stability. The proposed metric is based on vehicle lateral displacement calculated 1.07 seconds after initiation of the maneuver’s steering inputs.