Development of a Morphing Flap Using a Smart Soft Composite Actuator

Abstract

A morphing flap can change the trailing edge of a wing and act like a flap. The advantage of a morphing flap is that it can maintain the continuous surface profile of a wing, which can reduce turbulence, aerodynamic drag, vibration, and noise, versus the discontinuous geometry of conventional flaps and wings. The morphing technology, using smart materials, can be applied in various fields, such as biomimetic robots and aviation, Since it can achieve various deformations without complex mechanical components, such as motors and joints. These morphing technologies are advantageous to reduce the operating cost of the aircraft through weight saving. In this study, we designed and fabricated a smart soft composite (SSC) actuator, integrated with a shape memory polymer (SMP) scaffold and a shape memory alloy (SMA) wire. The fabricated SMP-SMA based SSC actuator can maintain a deformed state without additional current to heat the SMA. The measured maximum deformation angle of the actuator was 102° and the maintained angle was 70°. A morphing flap was then designed and fabricated using the SMP-SMA based SSC actuator. The aerodynamic performance of the morphing flap was evaluated in wind-tunnel experiments. The morphing flap generated additional lift force during actuation and the lift to drag ratio of the morphing flap was higher than that of a conventional flap

the maximum difference was 81% at 10°.