Series Active Disturbance Rejection Autopilot Design for Hyper Velocity Projectiles

This article presents a series active disturbance rejection controller (ADRC) autopilot design scheme with mini pin actuators for nonlinear hyper velocity projectile (HVP) system. In order to accurately describe the flight dynamics of HVP, a new nonlinear model with mismatched disturbances is established considering the aerodynamic characteristics of mini pin actuators. For compensating mismatched disturbances, series ADRC method is incorporated into double-loop (angle loop and angular loop) autopilot design, i.e., in the angle loop mismatched disturbances are observed and compensated in the virtual control calculation; in the angular loop, the observed matched disturbances are compensated in the mini pin control. In addition, both the mismatched and matched disturbances are considered as lumped ones including external disturbances, model uncertainties, coupling terms, etc. Finally, comparative numerical simulations with some traditional nonlinear control methods indicate that the proposed series ADRC HVP system has good robustness performance.