A robust trajectory tracking controller for four-wheel skid-steering   mobile robots
  A novel dynamic model-based trajectory tracking control law is proposed for a four-wheel differentially driven mobile robot using a backstepping technique that guarantees the Lyapunov stability. The present work improves the work of Caracciolo et al. (ICRA 1999), a dynamic feedback linearization approach, by reducing the number of required assumptions and the number of state terms. We also thoroughly investigate on a gain tuning procedure which is often overlooked for nonlinear controllers. Finally, the performance of the proposed controller is compared with the dynamic feedback linearization approach via simulation results which indicate that our controller is robust even in the presence of measurement noise and control time delay. 
Jae-Yun Jun (1 and 2), Minh-Duc Hua (1 and 2), Fa\"iz Benamar (1 and   2) ((1) Sorbonne Universit\'es, France, (2) CNRS, France)
math.OC