Suhel Khanb*, Yeswanth Saia, Mani Prabu S Sa, Palani I Aa, Pushpendra Singhc
Abstract:
In this investigation, a shape memory alloy (SMA) based aerodynamic composite Fin has been developed. In general, the missile fins play a crucial role in changing the direction of a conventional missile using motor arrangement. Therefore, SMA-based composite Fin might be a promising alternative to control the direction without using the motor. The composite Fin is made of laminated fiber polymer and SMA wire. Initially, rectangular composite structures have been developed with different wire pre-straining percentages, lengths, diameters, and configurations to understand their electrical actuation behavior. Based on the experiments, optimized parameters have been derived and applied to the composite fin. Adaptive composite actuation was performed via selective joule heating on the composite fin. Under optimized conditions, SMA-based composite structure shows maximum displacement of 65 mm with a maximum angle of 60 degrees before failure, where the diameter of 5% pre-strained SMA wire was 0.5mm at 6% of SMA to Composite ratio (volume of SMA/ volume of composite). Maximum displacement and failure analysis of the composite structure has been analyzed at optimized parameters.
Keywords: shape memory alloy (SMA), Nickel-Titanium (NiTi), UTM, adaptive stiffening.
Suhel Khanb, Vijay Choyala, Mani Prabu S. S.a, I. A. Palania and Pushpendra Singhc
Abstract:
Shape memory alloys (SMAs) offer an attractive way to build adaptive structures as their shape changes and remembered their shape under the applied external stimuli. The adaptive composite structures embedded with SMA wires have been developed using the hand layup process. In this work, the experimental investigation of the actuation behaviour of the SMA- based adaptive composite structures was carried out. This is achieved by imposing external active and passive heating. To investigate the actuation behaviour of the SMA-based adaptive composite structure different diameters of SMA wires and their configurations were considered. Based on the trial experiments, a voltage of 6V, a heating time of 5 sec, and a cooling time of 18 sec have been optimized for electrical heating. These heating conditions were used for all the thermomechanical analysis of SMA-based adaptive composite structures and all the samples were tested for multiple cycles of heating and cooling. The maximum deflection of 14 mm was observed for the composite structure embedded with 4 SMA wires of 0.5 mm diameter. Our fundamental study highlights the possibility of using SMA-based adaptive structures in electromechanical systems such as actuators and sensors.
Keywords: Adaptive composite structure; Actuation behaviour; Composite structure; NiTinol; Shape memory alloy (SMA).