An inner-loop/outer-loop architecture for an adaptive missile autopilot

We use retrospective cost adaptive control (RCAC) with a constant forgetting factor (CFF), variable forgetting factor (VFF), and Kalman Filter (KF) to control a planar missile with nonlinear dynamics and aerodynamics. RCAC/CFF, RCAC/VFF, and RCAC/KF are used within an inner-loop/outer-loop control architecture, where the normal acceleration command is used to update the pitch-rate command for use by the pitch-rate servo loop. This control architecture is necessitated by the fact that, except for circular arcs with constant velocity, the appropriate pitch-rate command cannot be inferred from the normal acceleration command. Aggressive commands are used to compare RCAC/VFF and RCAC/KF with RCAC/CFF.