Steering Control of the Autonomous Vehicle: CajunBot

This paper describes the steering controller of the CajunBot II, an autonomous vehicle designed for the DARPA Urban Challenge. The autonomous vehicle is a modified Jeep Wrangler Rubicon equipped with INS/GPS for localization, three sets of sensors and three single board computers. The control objective is to make the lateral error at a certain point ahead of the vehicle zero. The distance of this point from the vehicle is called the look-ahead distance. A proportional Integral controller augmented with a moving average filter to dump the yaw internal dynamics is proposed to achieve this objective. The steering controller was tested under full-scale conditions and its dynamic performances are discussed here.