Resonant passive energy balancing of morphing helicopter blades with bend–twist coupling

Abstract With increasing demand for rotor blades in engineering applications, improving the performance of such structures using morphing has received considerable attention. Resonant passive energy balancing (RPEB) is a relatively new concept introduced to minimize required actuation energy. This study investigates RPEB helicopter with lag–twist coupling. The structure rotating blade moving mass at tip considered under aerodynamic loading. To this end, three-degree-of-freedom (3DOF) reduced-order model used analyse and understand complicated nonlinear aeroelastic behaviour structure. includes pitch angle lagging blade, along motion mass. First, 3DOF simplified single-degree-of-freedom dynamics examine effect important parameters on response. results demonstrate that coefficient coupling direction moment are two play roles controlling angle, particularly phase. Then, neglecting forces, system studied investigate sensitivity its changes system. structural analysis can be tune order use resonant reduce force. A then performed presence forces controllability amplitude phase angle. show bend–twist distance between centre rotation (representing magnitude moments) significant determining dynamics.