The design and manufacturing of an active twist rotor blade for vibration reduction in helicopters are presented. The rotor blade is integrally twisted by direct strain actuation through embedded piezoelectric fiber composite actuators distributed along the span of the blade. Highlights of the analysis formulation used to design this type of active blade are presented. The requirements for the prototype blade, along with the final design results are also presented. Detailed aspects of its manufacturing are described. Experimental structural characteristics of the prototype blade compare well with design goals, and bench actuation tests characterize its basic actuation performance. The design and manufacturing processes permit the realization of an active blade that satisfies a given set of design requirements. This is used to later develop a fully active rotor blade system.
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