Design and experimental analysis of an active and passive camber morphing system for rotor blades

Abstract

Modern helicopters are equipped with rotor blades with exposed linkages, swashplates, and mechanical components. While such rotor blades have proved to be highly reliable, they are the leading cause to generate noise and vibration. In addition, the drag due to exposed linkages and hinges affects the helicopter performance. To overcome these issues and improve flight quality, researchers have worked on various techniques. One promising way to mitigate noise and vibration and replace the conventional control mechanism of the rotor blade is to use a trailing edge flap. Additionally, having a morphing trailing edge flap brings the opportunity to enhance rotor performance with even better flow quality over the rotor blade surface and is potentially lightweight. Consequently, the actuation of amorphing flap at higher frequencies helps tomitigate noise and vibration. However, morphing solutions are generally hard to implement even for fixed-wing aircraft because of the conflicting requirements of flexibility, strength, and weight. For rotorcraft, the concept to the physical realization of morphing solutions is even more challenging due to the complex loading environments, smaller blade volumes, and centrifugal forces. This is the first issue that the author tries to address with the present dissertation, i.e., to design, develop and do a feasibility study of an active trailing edge camber morphing system for rotorcraft....