System Identification of Post Stall Aerodynamics for UAV Perching

For a UAV to perch on a wire, aircraft control systems which operate far outside typical operating envelopes must be developed. The relevant transient aerodynamics at high angle of attack are not addressed today by control-accessible aerodynamic models. In this work, we present a set of physically-inspired basis functions which have enabled system identification of a nonlinear aerodynamics model along perching trajectories. Data is collected using a motion capture system which, critically, allows free-flight data from real system trajectories to be gathered. When simulated forward, the identified model accurately predicts the observed perching trajectories, making it an indispensable tool for designing feedback controllers that stabilize perching trajectories.