Open and Closed Loop System Identification of the Stryker 200 UAV

View Video Presentation: https://doi.org/10.2514/6.2022-2405.vid The Stryker 200 UAV is a rudderless, elevon-controlled, flying-wing aircraft with a 63-inch wingspan whose primary mission is a flight control testing platform. The aircraft is flight tested to obtain longitudinal and lateral-directional models using frequency-response system identification. Piloted frequency sweeps are accomplished in pitch, roll, and throttle in both fly-by-wire and manual modes of the Ardupilot-based autopilot. System identification is performed using CIFER to obtain the state-space models from both autopilot modes using the servo position commanded by the flight controller as the control input to the model. The resulting flight dynamic models are verified against doublets performed in each axis in manual mode on a different flight day. Both models show close agreement the doublet data. Despite kinematic consistency differences between the autopilot modes, the cost functions, Cramer-Rao bounds, and insensitivity of both models are all within acceptably low bounds, validating the predictive abilities of the models obtained in each autopilot mode.