Nonlinear Bank-To-Turn / Skid-To-Turn Missile Outer-Loop / Inner-Loop Autopilot Design with Θ - D Technique
Nonlinear bank-to-turn / skid-to-turn missile outer-loop / inner-loop autopilot design with theta - D technique
In this paper, a new nonlinear control method is used to design a full-envelope, hybrid bank-to-turn (BTT)/skid-to-turn (STT) autopilot for an air-breathing air-to-air missile. Through this new approach, called the θ − D method, we find approximate solutions to the Hamilton- Jacobi-Bellman (HJB) equation. An interesting and important feature of this new technique is that the nonlinear feedback law can be expressed in a closed form. In this autopilot design, a θ − D outer-loop and inner-loop controller structure is adopted. A hybrid BTT/STT autopilot command logic is used to convert the commanded accelerations from the guidance laws to reference angle commands for the autopilot. The outerloop θ − D controller converts the angle-of-attack, the sideslip, and the bank angle commands to body rate commands for the inner loop. An inner-loop θ − D nonlinear controller converts the body rate commands to fin commands. The nonlinear design is evaluated using a detailed six-degrees-of-freedom simulation. Simulation results show that the new controllers achieve excellent tracking performance and exhibit insensitivity to parameter variations over a wide flight envelope.
M. Xin et al., "Nonlinear Bank-To-Turn / Skid-To-Turn Missile Outer-Loop / Inner-Loop Autopilot Design with Θ - D Technique," Proceedings of the AIAA Guidance, Navigation, and Control Conference and Exhibit (2003, Austin, TX), American Institute of Aeronautics and Astronautics (AIAA), Aug 2003.
AIAA Guidance, Navigation, and Control Conference and Exhibit (2003: Aug. 11-13, Austin, TX)
Mechanical and Aerospace Engineering
Naval Surface Warfare Center
Keywords and Phrases
Autopilot; Bank to Turn; Hamilton-Jacobi-Bellman Equation (HJB); Skid to Turn; Angle of Attack; Sideslip; Six Degrees of Freedom Simulation
Article - Conference proceedings
© 2003 American Institute of Aeronautics and Astronautics (AIAA), All rights reserved.
01 Aug 2003