FEA based opto-mechanisms design and thermal analysis of a dynamic SFS with an ultra-long exit pupil distance

Abstract

The dynamic star field simulator (SFS) reproduces the actual operating conditions for the star tracker (STR) to assess its performance along with the flight motion simulator (FMS) in the hard-ware-in-the-loop (HWIL) simulation. The exit pupil distance of a traditional SFS is extremely short, which limits its application to large FMSs. To project the liquid crystal on silicon (LCoS) output to the STR entrance pupil, a 1250 mm ultra-long exit pupil distance SFS, operating in the broad waveband of 450–900 nm, is designed and implemented. In this study, the opto-mechanisms design and thermal analysis of the SFS are evaluated. The detailed design for key assemblies is specifically addressed to suppress negative heat effects. From the finite element analysis (FEA) results under different thermal conditions, the Zernike coefficients of 16 deformed optical surfaces in the projection module are solved using singular value decomposition (SVD), and the temperature adaptability is verified using a ray-tracing software. The preliminary SFS assessment confirms the simplicity of manufacture and excellent performance. The closed-loop opto-mechanisms design significantly improves the SFS reliability and enhances its suitability for large FMS use.