—Due to the slow tracking of acceleration command for pitch autopilot, Robust Servomechanism Linear Quadratic Regulator (RSLQR), three-loop and two-loop autopilot design are driven based on LTI model of missile plant to stabilize the nonminimum phase static unstably missile airframe. Robust Servomechanism Linear Quadratic Regulator (RSLQR) is proposed to design a bank-to-turn (BTT) missile autopilot. Longitudinal autopilot designed using optimal control theory, and is augmented by robust servomechanism design model to further extend the performance and stability of the system. The simulation results using RSLQR approach are compared with two-loop and three-loop designs. The comparison indicated that RSLQR and three-loop topology gives better tracking and more robustly than two-loop with a cascade PI compensator at different value of stability derivative .
—Two-loop autopilot, three-loop autopilot, flight control system, robust servomechanism LQR.
The authors are with School of Automation Science and Electrical Engineering, Beihang University BUAA), Beijing 100191, China (e-mail:
Cite: Emad Mahrous Mohamed and Lin Yan, "Robust Servomechanism LQR Comparison with Two- and Three-Loop Autopilot Designs," International Journal of Modeling and Optimization vol. 7, no. 1, pp. 28-33, 2017.