Estimation of Clamp Force in Brake-by-Wire Systems: A Step-by-Step Identification Approach

Elimination of a clamp force sensor from brake-by-wire system designs is strongly demanded due to implementation difficulties and cost issues. In this paper a new method is presented to estimate clamp force using the motor angular position of the actuator that can be sensed by an internal resolver. The estimator is a dynamic nonlinear model that is derived from a system identification approach where frequency domain analysis is merged with nonlinear compensation. The designed estimator is able to accurately track a wide range of sinusoidal, ramp and random clamp force signals. It is particularly tolerable to high speed cases as demanded by ABS controls. This paper is concluded with further investigation detailed that is necessary to ensure a robust clamp force estimator is developed.