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Modeling and Hovering Control of an Ducted-Fan UAV in Low Speed Crosswind

National University of Defense Technology has begun a research program to investigate and test ducted-fan propeller architecture for UAV designing. Development of a prototype continues to support ongoing research in the area of autonomous systems. In this paper, we build a nonlinear dynamic model of Ducted-Fan UAV for verifying appropriate controller behavior, and design a hierarchical controller for hovering flight of the UAV.