ROAD SURFACE STATE IDENTIFICATION DEVICE FOR VEHICLE

摘要

PROBLEM TO BE SOLVED: To discriminate between a sandy road and a pressurized snow road.;SOLUTION: An estimation value θ-hat of a pseudo maximum friction coefficient equivalent to an inclination of μ-s characteristic curve in the periphery of a slip ratio O based on a wheel speed estimation error ew and a car body speed estimation error ev and an estimation value μr-hat of a rolling resistance coefficient is calculated based on the car body speed estimation error ev so that the road surface state is estimated based on the pseudo maximum friction coefficient estimation value θ-hat and the rolling resistance coefficient estimation value μr-hat. The sandy road and the pressurized snow road having the similar road friction coefficients can be thus discriminated.;COPYRIGHT: (C)2001,JPO