Self-rigidizable Kapton-SMA conical booms: A comprehensive numerical and experimental study

Abstract

Inflatable gossamer space structures require structural rigidity after partial or complete out-gassing of the inflation gases. The current study focuses on the rigidity generation in a fully deployed, out-gassed Kapton laminated conical boom. A novel approach is applied to produce out-of-plane structural stiffness in the gossamer structure using the shape memory alloy (SMA) wires embedded between Kapton laminate membranes. The finite element analysis is performed to find the generated stiffness in the system and validated with the experimental results. To this end, an experimental set-up is developed to provide a stable and uniform thermal environment with the inflation facility. Additionally, different measuring devices are also employed in the test set-up to note the readings of pressure, temperature, and displacement sensors. Moreover, the Kapton and SMA material properties are found experimentally, and their material models are validated with published studies. Furthermore, constitutive equations of the SMA-Kapton composite are also included in the study. After that, a parametric study is done to know the effect of design and material parameters on the boom's stiffness.