A sliding mode missile pitch autopilot synthesis for high angle of attack maneuvering

A new approach to the synthesis of longitudinal autopilots for missiles flying at high angle of attack regimes is presented. The methodology is based on sliding mode control, and uses a combination of aerodynamic surfaces and reaction jet thrusters, to achieve controllability beyond stall. The autopilot is tested on a small section of the flight envelope consisting of a fast 180° heading reversal in the vertical plane, which requires robustness with respect to uncertainties in the system´s dynamics induced by large variations in dynamic pressure and aerodynamic coefficients. Nonlinear simulation results show excellent performance and capabilities of the control system structure