Uncertain Bicausal Bond Graph and Adaptive Fuzzy PID Controller for Fault-Tolerant Control

In this paper, a new fault-tolerant control scheme for uncertain systems is proposed based on uncertain bicausal Bond Graph and Adaptive Fuzzy PID Controller. The main objective is to make the control system act faster and more effectively in the presence of the faults and uncertainties. The scientific interest of the present work remains in integrating the benefits of uncertain bicausal bond graph model-based fault estimation and Fuzzy PID controller for effective fault-tolerant control of uncertain dynamic systems. For this task, the uncertain fault estimation is generated from the uncertain bicausal bond graph with perfectly separate nominal part from the uncertain part. Second, a fuzzy inference scheme is proposed to tune the PID gains in real-time, where the estimated fault and the errors over the estimated fault due to the presence of uncertainties are used in the fuzzy inference as inputs. Finally, the required input that compensates the fault effects are delivered to the system. The proposed approach is compared with the conventional one through an experimental application to the traction system of an omnidirectional mobile robot. The results show the effectiveness of the proposed approach.