Three-loop robust autopilot design for bank-to-turn missiles

For bank-to-turn missiles, a combined optimal/classical approach is brought out to design the autopilot. A three-loop autopilot of the pitch/yaw mix channel is designed using optimal control; meanwhile the singular value of the open-loop system is tested in frequency domain, to have the robustness of the system insured, and the obtained three-loop autopilot has the characteristic of simple structure, so it is more practical. Finally, the simulation results demonstrate the tracking performance and robustness of the autopilot, and also show that it satisfies the requirements for coordinate bank-to-turn.