Nonlinear Model-Assisted Control for Autonomous Parachute Precision Landing Recovery System

The application of circular parachutes for drones has gradually gained attention in civilian fields over the past decade, owing to their frequent usage at urban sites. This study developed an autonomous parachute precision landing recovery system (APPLRS) for risk mitigation in the large-scale use of drones. The system uses a nonlinear backstepping control algorithm based on a nonlinear dynamic system model for circular parachute control. Moreover, a nonlinear model-assisted extended state observer rejects disturbances caused by model uncertainties and wind. The simulation results demonstrate the anti-disturbance performance and verify the feasibility of APPLRS.