Low-Cost Manufacturing of Composite Hybrid Isogrid Mirror (CHIM)

"The Air Force requires lightweight, stiff and stable mirrors for use in high quality, space-based optical observation and energy projection systems. The current state-of-the-art uses various types of honeycomb core material with optical and composite facesheets. The honeycomb material, while excellent in compression, does not transfer the bending shear loads efficiently enough for truly lightweight optical systems. Honeycomb mirrors also are slow and costly to manufacture.The proposed program will develop a novel mirror system that uses highly efficient truss structures to provide bending stiffness for a thin meniscus mirror face sheet. The Composite Hybrid Isogrid Mirror or CHIM uses purely axially oriented, high-modulusfibers to provide an efficient, dimensionally stable support structure. This structure provides even, distributed load to the face sheet and reduces the system mass by using truss elements to transfer load rather than honeycomb plates. The plannedmanufacturing techniques reduce and simplify the steps required and thus reduce production cost and schedule.Foster-Miller will develop the system through a careful plan of design, modeling, sectional manufacturing and testing and full prototype manufacture and testing. Complete development of this technology will provide a mirror system that will enable better,lighter, and less expensive optical instruments. (P-020085) In addition to the myriad of Air Force missions such a