Patent US 5,684,696

A system and method for enabling an autonomous vehicle to track a desired path plans a continuous path to return to the desired path when the vehicle deviates from the desired path. The continuous path is determined based on the vehicle's position, the desired path, and a lookahead distance. The lookahead distance is the distance on the desired path within which the continuous path and the desired path converge. The lookahead distance may vary as a function of vehicle speed. In one embodiment of the present invention, the continuous path is determined as a quintic polynomial.