Stabilization of the general two-trailer system

Existing methods for nonholonomic feedback stabilization can only be applied to exactly nilpotentizable or flat systems. In this paper, a car towing two off-hooked trailers is considered as a canonical example of robot that does not fall into the above class. We show that exponential convergence to arbitrary configurations can be obtained by means of an iterative steering technique based on a nonhomogeneous nilpotent approximation of the system. Simulation results illustrate the performance of the method