Design of Robust H∞ Combined with PID Controller Using Fuzzy Logic for a Missile Autopilot

This paper presents the synthesis results of a robust H∞ (H-infinity) loop-shaping controller combined with a PID (Proportional-Integral-Derivative) controller using fuzzy logic for the pitch autopilot of a tail control missile. The results take into consideration the change of mass, moment of inertia, and aerodynamic coefficients. The combination of the control signal of the robust controller and the PID controller is formed on the basis of adjusting the membership function of fuzzy logic according to the ITAE (Integral of Time-multiplied Absolute value of Error) optimization criterion. The performance and robustness of the missile autopilot are verified by nonlinear simulation.