Active disturbance rejection control for heavy cargo airdrop operations

Abstract

In view of the strong nonlinear and coupling characteristics of the airdrop operations, a novel control method is proposed based on the active disturbance rejection control (ADRC) for decoupling control strategy of the pitch angle and airspeed. The unknown disturbances, including aerodynamic uncertainty and nonlinear coupling effect between the aircraft and cargo dynamics, are estimated and compensated with the extended state observer (ESO). Meanwhile, the nonlinear law state error feedback (NLSEF) is adopted to restrain the compensation residual. Simulation and flight quality evaluation shows the satisfactory capacity and strong robustness of the proposed control method in guaranteeing the airdrop task and flight safety.

Safety Assessment of Transport Aircraft Heavy Equipment Airdrop: An Improved STPA-BN Mechanism

“…Methods focused on the risks of human contributions to the stability domain of this human-machine-environment closedloop system were proposed to study problems during a heavy equipment airdrop such as pilots operating too violently or airdropper's inappropriate decision making [4,5]. Focusing on mechanical risks, control methods have been proposed to study aircraft-cargo coupling characteristics, equipment blocking failure, equipment sliding disturbance, equipment stability under drastic changes during heavy equipment airdrop, and constraints between the extraction parachute and the equipment [6][7][8][9][10]. Focusing on risks posed by the environment, methods have been developed to improve the anti-interference of aircraft to ensure the robustness of heavy equipment airdrop to guard against effects of lateral wind, disturbed wind, and atmospheric turbulence during a heavy equipment airdrop [11].…”