Method and apparatus for minimizing driver disturbance in a limited by-wire active steering system

摘要

A method is provided for limiting a steering angle overlay applied by a steering actuator in a limited by-wire active front steering (AFS) system. The method includes determining a maximum rate limit for the steering angle overlay in order to minimize an undesired disturbance to the driver in the form of a torque and/or angle feedback while maximizing the rate of steering overlay allowed for a given set of vehicle operating conditions. The maximum rate limit is determined by a function of the input steering rate and braking level. A limited AFS system includes both steering and braking input devices, a steering actuator, and a controller having an algorithm. The controller uses the algorithm to calculate the maximum overlay rate limit and limits the steering actuator to the maximum overlay rate limit.