A New Algorithm for ABS to Compensate for Road-Disturbance

The present ABS is controlled by the slip ratio and the wheel acceleration. On rough roads, the slip ratio is weighted to eliminate the wheel velocity fluctuation. That results in poor performance of the ABS, Therefore a new algorithm is investigated without the slip ratio.

The algorithm consists of major two concepts. One of which is to shift the wheel acceleration threshold which determines the initiation of the brake-pressure reduction by the road friction coefficient and the disturbance. The other is to determine the proper duration for the pressure reduction by the road friction coefficient at same time.

The new algorithm was estimated by computer simulations. Therefore, the reduction of velocity-fluctuation, more effective steerability and a shorter stopping-distance can be expected.