Actuator fault compensation tracking control for multi linked 2WD mobile robots

Abstract

In this paper, a control scheme for multi linked mobile robots is proposed to accommodate actuator faults which are uncertain in time, pattern and value. First, a configuration of Ν (Ν > 1) mobile robots with fixed links is described, and its kinematics and dynamics are modeled. Then, a multiple-model based control scheme is developed to compensate for actuator failures, consisting of a kinematic controller, multiple dynamic controllers and a control switching mechanism. The kinematic controller is based on the transformation of the considered kinematics into a chained-form system, after that a recursive technique is used to derive the kinematic control law for any Ν robots configuration, based on which, multiple dynamic controllers are designed considering all possible failure cases. From these dynamic controllers, an appropriate one is selected to generate the applied control signal by the control switching mechanism using multiple reconstruction dynamic signals to ensure desired system performance. Simulated fault scenarios are presented for four mobile robots with fixed links to illustrate the performance of the proposed approach.