Compliant design for flapping mechanism: A minimum torque approach

Compliant mechanisms are suggested as alternates for simplification of assembly and for miniaturization. It is shown here that a significant reduction in running torque could be achieved through proper design. The dynamics of a four-bar crank-rocker mechanism, suitable as a flapping mechanism and consisting of two flexural hinges is analyzed. The peak driving torque is minimized by modifying the stiffness of the flexural hinges and the unstrained positions of the flexural hinges. A reduction of the order of 2.85 in the peak driving torque is achieved in a specific mechanism considered.