Using a more control-oriented terminology, the point-to-point motion task is a stabilization problem for an (equilibrium) point in the robot state space. For a car-like robot, two control inputs are available for adjusting four conguration variables, namely the two cartesian coordinates characterizing the position of a reference point on the vehicle, its orientation, and the steering wheels angle. More in general, for a car-like robot towing N trailers, we have two inputs for reconguring n = 4+N states. The error signal used in the feedback controller is the di erence between the current and the desired conguration
