Characterization of a Solar Sail Membrane for Abaqus-Based Simulations

Photonic solar sails are a class of advanced propellantless propulsion systems that use thin, large, lightweight membranes to convert the momentum of light from the Sun into thrust for space navigation. The conceptually simple nature of such a fascinating propulsion system requires, however, advances in materials, packaging, deployment, and control of a very large space structure. In this context, the finite element method (FEM), implemented in a robust and flexible software such as the commercial software Abaqus, represents a fundamental instrument to progress with the practical study of this promising propulsion system concept. In particular, in a typical (medium-size) square solar sail design process, the FEM-based analyses are used to better understand fundamental aspects of structural design, such as, for example, membrane pre-tensioning, deformations induced by Solar Radiation Pressure (SRP), and the buckling of reinforcing booms. The aim of this study is to describe an effective procedure to model a classical square solar sail structure into a typical commercial software for finite element analysis, such as the well-known suite Abaqus. In particular, we compare various membrane pre-tensioning techniques (useful for increasing the membrane's bending stiffness) and describe possible approaches to applying the SRP-induced load in a realistic way. Additionally, the flexibility of the structure under the solar sail loads and the criticality of section shape and boom size are taken into account, with particular regard to the problem of structural instability. In this context, performance and critical issues of different structural solutions are discussed and compared, allowing an improvement in the preliminary design phase of solar sails to be obtained.