Actuation of trailing edge flap in a wing model using piezostack device

Abstract

This paper presents a methodology to actuate trailing edge flap in a wing model using a high performance piezostack device. A composite wing model was built around this piezostack actuator with integrated mechanical amplification. The free displacement and block force of this high voltage actuator were respectively determined as 28 mil and 16 Ib at 1000 volts. The linear motion of the actuator was converted to rotary motion for flap actuation using a hinge offset mechanism. This model was tested to evaluate the performance of flap actuation without and with aerodynamic forces. The flap deflection was measured using a Hall sensor, and a maximum of 8.5 deg flap deflection was achieved. The influence of free stream velocity and angle of attack on flap deflection was examined. A 30% decrease in flap deflection at free stream velocity at 95 ft/sec was noticed. Angle of attack of 10 deg did not change the flap deflection. Flap deflection was predicted from forcedisplacement relation of actuator and calculated hinge moment and good correlation between experiment and prediction was achieved.