Local testing and reduced model validation of thermal-formed thin-film polyimide panels

Stiff, ultra-lightweight thermal-formed polyimide panels considered here are examples of next-generation gossamer structures that resolve some of the technology barriers of previous, membrane-dominated gossamer designs while maintaining their low mass and low stowage volume characteristics. The research involved statically characterizing and modeling several of these panels to develop validated computer models which can be used to determine the effects of changing manufacturing parameters and scalability. Static characterization showed substantial local nonlinear behavior that was replicated by new physics-based finite element models in which the test data were used to define model parameters. These simple nonlinear spring models were significantly smaller than shell element models of the same structure and exhibited superior performance by closely matching the experimental data. Overall, the research contributes to the total knowledge base of gossamer technologies, advances stiff panel-based structures toward space qualification, and demonstrates their potential for use in apertures and other spacecraft.