Distributed output feedback consensus tracking control of multiple nonholonomic mobile robots with only position information of leader

Abstract

In this paper, distributed output feedback consensus tracking control of multiple nonholonomic mobile robots with limited information of leader is studied. Different from the existing results, the considered consensus problem has the following features: (i) each robot is described by a second-order dynamic model with parametric uncertainty and external disturbances, (ii) the global information of the directed graphs is not required, (iii) only the position of the leader is available for a subset of robots and thus its velocity information is no longer needed. To solve such a problem, an adaptive output feedback control scheme which involves estimator, observer and controller design is proposed. A fully distributed estimator is constructed to estimate the position of the leader for each robot. Based on the estimated information, an adaptive observer-based output feedback controller is designed to realize consensus tracking. It is shown that the boundedness of all the signals in the resulting closed-loop system is guaranteed, and the consensus tracking error of the system converges to an adjustable neighborhood of zero by appropriately choosing design parameters. Simulation results are provided to verify the effectiveness of the proposed scheme.