System and method for closed loop speed control for stop and go applications

摘要

A system and method for closed loop speed control for stop and go applications allowing adaptive cruise control operation at low speeds below vehicle idle speed by use of traction control system braking. The system comprises: proportional controller to hold the vehicle speed at the desired vehicle speed; integral controller to reduce vehicle speed when the adaptive cruise control cuts off speed control; stopped controller to overcome static friction after a vehicle stop; open loop controller to hold the vehicle speed a set speed below the vehicle idle speed. The system also provides a switch to set the torque command to zero for large positive speed control errors, such as when the desired speed is above the vehicle idle speed, and a transition logic to provide a smooth transition between alternate control mode operation and speed control mode operation.