Studying the stability of a four rotor helicopter prototype using the lifting operators

In this paper, a study of a four rotor helicopter prototype control is presented. Firstly, the different aspects of the prototype construction are described, making a special emphasis in the mechanics, the design of the sensorial and actuation systems and the prototype control. Next, the formalism of the lifting and inverse lifting operators is presented. As it will be shown, they can be applied to this multifrequency system in order to allow using a simple lineal method to analytically determine the closed-loop system stability.