Abstract
The performance, accuracy, and observability of a model-free angle of attack and angle of sideslip estimator are presented. The estimator does not require an aircraft dynamic model; rather, it only relies on measurements from a GPS receiver, an inertial measurement unit, and a pitot tube. The estimator is an inertial navigation system (INS)/GPS extended Kalman filter augmented with the states to account for wind and an additional measurement from a pitot tube. It is shown that the estimator is conditionally observable. Conditions (maneuvers) that enhance its observability are identified. A bound on the angle of attack and angle of sideslip estimate uncertainties is derived. The effect of INS/ GPS, horizontal and vertical wind uncertainty on the accuracy of angle of attack and angle of sideslip estimate is assessed. Simulation and flight-test results of the method are presented. The results show that the 1 − σ bound on a small, slow-flying unmanned aerial vehicle for angle of attack and sideslip angle estimates are about 5 and 3 deg, respectively.
Original language | English (US) |
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Pages (from-to) | 1471-1486 |
Number of pages | 16 |
Journal | Journal of Aircraft |
Volume | 56 |
Issue number | 4 |
DOIs | |
State | Published - 2019 |
Bibliographical note
Publisher Copyright:Copyright © 2019 by Kerry Sun, Christopher D. Regan, and Demoz Gebre-Egziabher. Published by the American Institute of Aeronautics and Astronautics, Inc.