Effects of Canopy-Payload Relative Motion on Control of Autonomous Parafoils

摘要

An eight-degree-of-freedom model is developed that accurately models relative pitching and yawing motion of anpayload with respect to a parafoil. Constraint forces and moments are found analytically rather than using artificialnconstraint stabilization.Aturn rate controller common in precision placement algorithms is used to demonstrate thatnrelative yawing motion of the payload can result in persistent oscillations of the system. A model neglecting relativenpayload yawing failed to predict the same oscillations. It is shown that persistent oscillations can be eliminated bynreduction of feedback gains; however, resulting tracking performance is poor. A reduced-order linear model isnshown to be able to adequately predict relative payload dynamics for the proposed turn rate controller on the fullneight-degree-of-freedom system.