Missile Roll Autopilot Redesign Based Advanced Fin Actuation System Modeling

The design of missile autopilot is an essential issue as it always shares several challenges. The accuracy of impact is highly affected by designed controller accuracy and robustness against the target maneuver and missile nonlinearity resources. The design of autopilot controllers is highly affected by the derived system transfer function as much as it expresses the detailed system dynamics and nonlinearity resources. In this paper, we highlight the importance of advanced actuation system modeling considering nonlinearity resources. The nonlinear model parameters are derived, identified, and evaluated through simulation of missile roll autopilot. Inserting the developed system model to the three-loop missile autopilot presented a poor performance for the time and frequency stability parameters so in this paper a redesign procedure is proposed for designing a more realized controller. The gain scheduling PID controller based optimized genetic algorithm is developed for selected trim points based on missile dynamic pressure and trajectory parameters. The simulation of roll autopilot loop results presents sufficient efficiency and robustness for the selected trim points different input signals with rapid amplitude and frequency changes for high dynamics systems.