Dynamics research on actively controlled swashplateless rotor

This study presents the design, dynamic model, and dynamics research of a new cyclic pitch control strategy in motor-driven rotorcraft. In this strategy, the control response and flapping feature of conventional rotor systems can be obtained by imposing (1) a lag-pitch coupling on rotor blade and (2) an additional sinusoidal rotational speed of rotor shaft without any actuators or swashplate. This study establishes a refined nonlinear dynamic model including the effects of pitch motion, and figures out the fundamental dynamic characteristics of this novel configuration. Analyses of its mechanical stability, dynamic responses and stability in hover are also conducted. The model in this research, compared with the previous linear model, improves the predicting accuracies of dynamic responses remarkably. A preliminary understanding of this novel rotor's dynamic mechanisms is gained by this study.