Patent ID: 6266602
Filing Date: 2001-07-24
Classification: B60T

Abstract:
A road surface condition determination system for an automotive vehicle, comprising:wheel-speed sensors detecting wheel speeds of each of road wheels; anda control unit being configured to be electrically connected to said wheel-speed sensors for processing a wheel-speed data signal from each of said wheel-speed sensors, said control unit comprising:(a) a wheel-speed fluctuation arithmetic-calculation section which calculates a wheel-speed fluctuation of each of the road wheels on the basis of a previous value of the wheel-speed data signal and a current value of the wheel-speed data signal,(b) a first absolute-value arithmetic-calculation section which calculates an absolute value of the wheel-speed fluctuation of each of the road wheels,(c) a first integration section which produces a first integrated value of the absolute values of the wheel-speed fluctuations of the road wheels,(d) a smoothing section which makes a smoothing operation to the first integrated value to produce a smoothed value, and(e) a road-surface condition determining section which determines a road surface condition on the basis of the smoothed value.