Satellite Imaging Optical Metering Structure
Application
Space. A high-resolution optical metering structure for a commercial satellite instrument.
Previous Limiting Technology
Near zero CTE precision optics for space applications have been prohibitively expensive for commercial ventures. Stiffness and CTE requirements mandated use of expensive materials and processes.
Challenge
Our customer had a tight schedule and constrained cost requirements. Some of the materials that would make the program possible did not have processing and structural data. Thermal and moisture stability, as well as specific stiffness, continued to be a concern. We believed we could find solutions with new composite materials being developed to support lower cost solutions.
Solution
At Rock West Composites, new combinations of composite materials are constantly being developed to support lower cost solutions. Our team collaborated with a broad base of suppliers and brought our in-depth knowledge of design and manufacturing processes to satisfy historically expensive design risks and help our customer’s engineering team through their analysis processes.
For the larger metering tube, we selected a newly developed 110mis pitch-based fiber, a 16K yarn version of what used to be made from a 2K Yarn. Combined with advanced fiber spreading technology, this yields a 0.005”/ply cyanate ester prepreg with spacecraft material quality. The material kept the cost contained while also meeting CTE and CME requirements. We brought this new material to flight-ready status through qual-level acceptance testing on the actual laminates used in the structural details. We also developed a new process for hand wrapping the large tube shape, which was technically challenging due to fiber stiffness.
For the primary support structure, a thick solid laminate, we used ultra high modulus pitch prepreg from our commercial off-the-shelf material supply. This 12K pitch fiber is 92 msi, is well characterized, has significant space heritage, and achieves very high stiffness isotropic laminates that help to reduce cost and schedule.
Rich Simons, Deep Sky Instruments
Doron Shterman, ImageSat International