Analysis and Design of Active Morphing Units Based on SMA Actuators

Morphing wings can change their shapes in flight to optimize aircraft’s aerodynamics, which increases aircraft’s performance for a given flight stage. This paper introduces an active morphing unit (AMU) which can deform by the two-way actuator comprising two one-way shape memory alloy (SMA) elements. The mathematical model and the forward kinematics of AMU are established. The structure of AMU is design. Then, the paper demonstrates that the combination of AMUs can function as the main spar of distributed multi-freedom active morphing wing. Three different combination strategies of AMUs are analyzed by forward kinematics and realizable variable geometries of wing. A configuration sample of one-dimension morphing wing is presented to demonstrate a combination strategy. The rotation function and stiffness of AMU prototype are tested. Experimental results illustrate that AMU can realize desired deformation and has high stiffness. This research will lay the foundations of next generation morphing aircrafts.