Coupled System Identification, Flight Controller Design, and Wind Sensing Using KHawk Flying-Wing UAS

Abstract

This dissertation focuses on new system and method development using KHawk flying-wing unmanned aircraft system (UAS) for system identification, controller design, and wind sensing applications. This dissertation attempts to provide a start to finish example for how to build and modify a low-cost remote controlled (R/C) aircraft for UAS research purposes, perform system identification to determine the dynamic aircraft model, design a robust lateral loop flight controller for disturbance rejection, estimate flow angles for stall detection, and measure wind data including both prevailing wind and turbulence. First, new design, building, and flight test procedures are provided for KHawk flying-wing UAS family including a series of small, low-cost, and durable UAS that can support atmospheric and aerospace researches. Next, a coupled system identification and robust controller design method is examined for the lateral loop of KHawk flying-wing UAS. A fractional order PID (FOPID) controller is also introduced and optimized for turbulence rejection using a genetic algorithm based multi-objective optimization approach. Then, a new stall detection method is introduced using a complimentary filter to determine the inertial angle of attack (AOA) of the UAS together with flight analysis of typical stall patterns of small flying-wing UAS. And finally, the developed KHawk flying wing UAS is used for prevailing wind and turbulence measurement while flying over a prescribed fire.