Non-model-based control for a wheeled mobile robot towing two trailers

Abstract

In this paper, trajectory tracking control of a wheeled mobile robot (tractor) with two trailers including three nonholonomic constraints is analyzed. This system is a nonlinear, under actuated mechanical system subjected to nonholonomic kinematic constraints. First, system dynamic equations are obtained. A non-model-based control algorithm using PD-action filtered errors has been used in order to control the wheeled robot. Non-model-based controllers are always more appropriate than model-based algorithms due to lower dependency on dynamic models, lower computational costs, and also robustness to uncertainties. Asymptotic stability of the closed-loop system has been investigated using Lyapunov method and Barbalat’s lemma. Finally, in order to show the effectiveness of the proposed approach simulation and experimental results have been presented. Obtained results show that without requiring a priori knowledge of plant dynamics, and with reduced computational burden, the tracking performance of the presented algorithm is quite satisfactory.