Structural Research Of The Segmented Morphing Wing Based On The SMA Modular Actuator

Traditional actuation methods of morphing wing have some defects, such as structure bulky and low power density, while the emerging smart material technology has improved this aspect to some extent, with high sensitivity, efficiency and precision. Based on the research about the actuation property of Shape Memory Alloy (SMA) wires, this paper designed a double-V modular SMA actuator applied on a trailing edge segment wing structure, inducted the actuation mechanism of the actuator. The aerodynamic simulation was completed and it was found that this type of actuation design enable the improvement of the wing’s aerodynamic characteristics, which will provide both theoretical and practical directive significance for the application of SMA in morphing wing.The basic properties of SMA and shape memory mechanism were researched and the thermodynamics and dynamics during the phase transition of SMA were analyzed. The Tanaka one-dimensional model was selected to build the constitutive equation of SMA memory effect, which was used to analyze the morphing mechanism under three different reversion conditions. Based on the SMA property testing platform, the basic parameters of the0.5mm diameter SMA wire were measured, such as the phase transition temperature, the maximum reversion strain (approximately8%), and the maximum reversion pull (161.7N under4%strain), which lay the theoretical and experimental data foundation for SMA actuation modular.A trailing edge segment wing structure was designed to achieve the accumulative deflection of the trailing edge, based on a Double-V SMA actuator. Analyzed the displacement of the SMA actuator, established the basic model of the wing structure and the morphing process was simulated. The formular of the maximum deflection angle of the Double-V SMA actuatorand the accumulative deflection of the trailing edge were constructed. The mechanical model and output torque of the SMA actuator were analyzed. It was proved that the actuation capability can be adjusted rapidly through changing the fundamental dimensions of the actuator structure, while this design is quite convenient for removal and replacement. CATIA was used to build the three-dimensional model and to simulate the morphing process of the wing. The aerodynamic simulations of both the original and deformed airfoils were completed, which proved that this reconfigurable can effectively improve the lift efficiency of the original airfoil NACA4412under the attack angles from0°to10°, which proved that this reconfigurable can effectively improve the performance of the aircraft.