Developement of Piezo-Hydraulic Actuation Systems Technology for use on a Helicopter Trailing Edge Flap

Abstract

The purpose of this study was to create a proof-of-concept piezoelectric actuator system capable of meeting the performance requirements necessary for actuation of a trailing edge flap for a helicopter main rotor blade. Due to extremely small displacements produced by piezoelectric actuators, their output is amplified several times in order to produce the required displacement for this device. The amplification is accomplished in two stages. The first stage, mechanical amplification, uses differential length lever arms to increase the piezoelectric actuator output. The second stage, hydraulic amplification, is coupled to the first stage and uses differential area pistons to further amplify the output of the mechanical amplifier. The actuation systems force and displacement output is characterized based on frequency.