Antilock brake system with closed loop apply bump

摘要

A vehicle antilock brake system provides an adaptive apply bump period at the beginning of the apply phase of a antilock brake pressure cycle that provides rapid recovery of the correct amount of pressure for all braking conditions. The apply bump period is established based upon the wheel acceleration and the peak acceleration attained by the wheel during recovery from an incipient wheel lock condition. In particular, the apply bump is initiated when recovery from an incipient wheel lock condition is first sensed and thereafter terminated when the wheel acceleration decreases to below a threshold value that is a predetermined function of the peak acceleration of the wheel during recovery from an incipient wheel lock condition in the ABS pressure cycle.