Modular tracking controller for N-trailers with non-zero hitching offsets

The paper presents the concept and stability analysis of a trajectory-tracking feedback control system for truly N-trailer robots equipped with arbitrary number of trailers interconnected by the non-zero hitching offsets. Thanks to application of the cascaded-like control structure the considered solution is modular and highly scalable with respect to a number of trailers. Formal analysis of the closed-loop system provides sufficient conditions for asymptotic tracking of a whole set of the so-called segment-platooning reference trajectories with constant as well as time-varying curvature under assumption of sign-homogeneous hitching of trailers. Generality of the concept description together with formal analysis presented in the paper fills in some extent the gap which arose in the literature in the context of trajectory tracking with N-trailers of differentially non-flat kinematics. Simulation examples validate utility and modularity of the control method.