Robust H a directional control for a sampled-data autonomous airship

A robust H (a) directional controller for a sampled-data autonomous airship with polytopic parameter uncertainties was proposed. By input delay approach, the linearized airship model was transformed into a continuous-time system with time-varying delay. Sufficient conditions were then established based on the constructed Lyapunov-Krasovskii functional, which guarantee that the system is mean-square exponentially stable with H (a) performance. The desired controller can be obtained by solving the obtained conditions. Simulation results show that guaranteed minimum H (a) performance gamma=1.4037 and fast response of attitude for sampled-data autonomous airship are achieved in spite of the existence of parameter uncertainties.