A wet-road braking distance estimate utilizing the hydroplaning analysis of patterned tire

A wet-road braking distance estimate for the vehicles equipped with ABS (anti-lock brake system) is presented in this paper. The entire speed interval at braking is divided into several uniform sub-intervals, and the energy conservation law is applied to individual sub-intervals to predict the intervalwise braking times and the resulting velocity profile at braking and the total braking distance. The proposed method is based on a numerical-analytical approach such that the frictional energy loss of the patterned tire is computed by 3-D hydroplaning analysis while the other at the disc pad is analytically derived. The operation of ABS is numerically implemented by controlling the tire angular velocity such that the preset tire slip ratio on the wet road is maintained. The tire hydroplaning is analysed by generally coupling an Eulerian finite volume method and an explicit Lagrangian finite element method. Illustrative numerical experiment is presented to support the validity of the proposed estimate. Copyright q 2006 John Wiley & Sons, Ltd.