Distributed Tracking of Multiple Under-Actuated Lagrangian Systems with Uncertain Parameters and Actuator Faults

Abstract

A distributed adaptive controller is proposed for a class of under-actuated Lagrangian systems under a directed communication graph to control the actuated variables to track a dynamic leader and keep unactuated ones bounded. A finite time observer is introduced to estimate the leader’s velocity. Based on the two sliding variables defined for the actuated and unactuated channels, the adaptive controllers are designed for the under-actuated Lagrangian systems with or without actuator faults. The convergence of the proposed controllers is proved based on the separation principle between the estimation and control. Finally, experiments are conducted to verify the effectiveness of the proposed controllers.