Rapid Design & Control of Small Unmanned Aerial Systems

Abstract

As the Federal Aviation Administration (FAA) begins to allow commercial Unmanned Aircraft (UA) flights in the United States, businesses and organizations of all types are exploring a wide variety of potential applications. When compared to manned alternatives, these UA have the capability to reduce cost, improve efficiency, expand capabilities, and increase safety. One class of UA that shows particular promise is small Unmanned Aerial Systems (sUAS). These aircraft have lower takeoff weights and smaller form factors than manned alternatives. Yet they often have similar (or better) data-gathering capabilities at a fraction of the price. The benefits of this technology and the corresponding demand is clear. However, while unmanned aircraft are relatively low cost, they can still be a large expense. This is due to the high development, production, and implementation costs that frequently accompany flight vehicles.

One possibly significant source of expense in autonomous vehicle design is the development of the control system. This work presents a compilation of design methods, when taken as a whole, serve to reduce the time and expense of designing a control system for sUAS. The modeling methods presented include vehicle dynamics, vehicle aerodynamics, propeller aerodynamics, and electric motor dynamics. The modern H∞ control design method was used with the resulting high-fidelity 6 DOF model to produce controllers for hover and forward flight configurations of a tiltrotor sUAS.