Direct sensing of rough road conditions are used to modify operation of a
wheel slip control system. At least one suspension sensor (139) senses an
operating parameter of the suspension system. A road surface classifier is responsive
to the suspension pension sensor (139) for generating a road surface signal
representing a roughness of a road surface over which the vehicle travels. A braking
system includes a wheel speed sensor and a brake actuator. An active braking control
detector wheel slip in response to the wheel speed sensor (108) during at
least one of braking or accelerating of the vehicle and modulates the brake actuator
in response to the detected wheel slip. The active braking control is responsive
to the road surface signal for modifying modulation f the brake actuator as a function
of the road surface signal.