Reduced-Order Dynamic Modeling and Stabilizing Control of a Micro-Helicopter

Soldier-portable UAVs enhance combat situational awareness by providing an over-thehorizon surveillance platform. This advantage can be multiplied by using multiple microhelicopters (< 20 g, < 20 cm) that operate cooperatively to obtain synoptic vantage points. Cooperative control of multiple helicopters using theoretically justified control laws requires a mathematical model of micro-helicopter dynamics, which can be quite complex. This paper describes an idealized 3D dynamic model of a micro-helicopter whose control input is the thrust of the main and tail rotors. We use the dynamic model to synthesize trackingcontrol algorithms for altitude and yaw or altitude and yaw-rate. We further validate the closed-loop model by experimentally demonstrating altitude control of a single helicopter using motion-capture feedback. By leveraging existing results for cooperative control of the closed-loop helicopter model, this paper provides the foundation for the design of a cooperative micro-helicopter surveillance network.