ROAD SURFACE STATE PREDICTING DEVICE

摘要

PROBLEM TO BE SOLVED: To accurately predict the maximum road surface frictional coefficient without being affected by a variation in a road surface state and without providing excessive vibration to a vehicle. SOLUTION: Based on a brake oil pressure signal Pb in time series from a pressure sensor 16 and a wheel speed signalωw in time series from a wheel speed sensor 22, a braking force gradient predicting part 23 obtains an origin braking force gradientα0, an instantaneous braking force gradientα, and a braking force F at that time. The maximum braking force predicting part 24 calculates the maximum braking force Fmax by using the origin braking force gradientα0, instantaneous braking force gradientα, and braking force F at that time. Aμmax predicting part 25 obtains the maximum road surface frictional coefficientμmax by substituting the maximum braking force Fmax obtained in the maximum braking force predicting part 24 and a wheel load W.