L1 adaptive dynamic inversion missile autopilot with PI structure and adaptive sampling

An L
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adaptive controller with piecewise continuous (PC) adaptation law augmenting a nonlinear dynamic inversion (NDI) autopilot has been applied to a highly agile, tail-controlled missile. Here proportional integral (PI) structure has been used in inner loop for better tracking and robustness. Adaptive sampling has also been introduced for less computational load. Firstly a two time scale separated NDI autopilot is designed to control the pitch and yaw accelerations in the body-fixed frame while maintaining a desired roll angle. The baseline NDI autopilot is augmented with proposed L
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Adaptive autopilot using PI structure and adaptive sampling to overcome the potential performance degradation due to modeling uncertainties. The advantages of proposed autopilot are demonstrated via simulations of a high-fidelity six-DOF missile model, in which worst case uncertainties are considered.