Design and static testing of a trailing-edge flap actuator with piezostacks for a rotor blade

This paper presents the development of an actuator for a trailing edge flap on a full-scale helicopter rotor blade using a high performance piezoelectric stack device. The actuator was designed and constructed using two identical piezostacks that were selected among commercially available actuators through a systematic testing. To calculate the aerodynamic requirement of the flap actuator, an analytical model was formulated using quasi-steady aerodynamics. A new amplification device utilizing double-lever mechanism was designed and fabricated. An amplification factor of 19.4 and the constant response covering up to 8/rev were obtained experimentally under non-rotating condition. It was shown that the present flap actuator is capable of achieving the required flap deflection to actively control rotor vibration.