Adaptive Output Feedback Control of the IPMC Propelled Vehicle With Unknown High Frequency Gain Matrix

This paper presents model reference adaptive control (MRAC) of underwater vehicle propelled by the Ionic polymer metal composite (IPMC) actuator. Trajectories of the vehicle are controlled by simultaneously controlling the bias and amplitude of the sinusoidal voltage applied to the IPMC actuator attached at the real end of the vehicle. It is assumed that the system parameters as well as high frequency gain matrix are unknown. Using Lyapunov stability theory and factorization of the high frequency gain matrix, an adaptive output feedback control is designed for trajectory control of a heading angle and a speed of the vehicle. In the proposed approach, SDU (Square Diagonal and Upper triangular matrix) decomposition of the high frequency gain (HFG) matrix is used. Only signs of the leading principle minors of the HFG matrix are assumed to be known. Simulations results are presented to show that precise trajectory control of the heading and speed is achieved in spite of the coupling between controlled variables.