Road surface condition detection system for motor vehicles with ABS derives state of road surface from smoothed, integrated absolute values of detected wheel speed fluctuations

摘要

The system has wheel speed sensors for all wheels and a control and regulating unit that processes the wheel speed signals from each sensor. The unit contains a wheel speed fluctuation arithmetic computation stage (a), an absolute value computation stage (b) for the wheel speed fluctuations, an absolute value integration stage (c), an integrated value smoothing stage (d) and a road surface state determination stage (e) that derives the state from the smoothed values. An Independent claim is also included for an ABS system that uses a road surface condition detection system