Structural design challenges for a Shuttle-launched Space Interferometry Mission

摘要

The Precision Structure Subsystem (PSS) for the Space Interferometry Mission (SIM) is a large composite structure designed to house the interferometer optics in a structurally and thermally stable environment on orbit. The resulting design requirements of the PSS must be weighed against the demands of the baseline launch vehicle: the Space Shuttle. While a Shuttle launch provides new opportunities for the mission, it also presents new challenges. Many of these challenges are reflected in the design of the PSS, including structural stability for supporting the optics on orbit, launch vehicle interface considerations (acoustic and stress loads), minimization of launch mass to provide maximum payload to orbit, thermal control to achieve necessary structural stability and a stable thermal environment for the optics, and isolation of the optics mounts from jitter sources and microdynamics effects. Many of these design challenges result in inherently conflicting requirements on the design of the PSS. Drawing on our experience with large composite structures such as the Chandra X-ray Observatory, TRW has created a conceptual design for this structure that addresses these challenging requirements. This paper will describe that conceptual design including trades and analyses that led to the design.