Miniaturization Methods for Deep Space Microspacecraft

Due to the shrinking NASA budget, future scientific spacecraft programs will be driven by their "life-cycle" cost. This cost figure, which includes development integration, launch, and operation, can be reduced by making spacecraft smaller and more autonomous. Such miniature spacecraft allow the launch of several microspacecraft on a single launch vehicle or the launch of a single microspacecraft as a "piggy-back" rider on top a primary payload. Although each of these small spacecraft will not be capable of conducting the diversified science that is accomplished by such grand vehicles as Voyager and Cassini, a group of microspacecraft can conduct a composite of many different kinds of valuable science missions as well as enhance overall mission reliability. The methodology used in the design of microspacecraft is different than that which is used for traditional planetary spacecraft. This design approach involves the incorporation of advanced miniaturizing technologies as well as the modification of the system architecture so that it can support the desired small mass and size. The progress in miniaturization is evolutionary: size can be reduced from one design to the next by further modifying the system architecture and incorporating even more advanced technologies. This paper will cover the specific approaches used in the evolutionary miniaturization process as well as the advanced technologies needed to build a miniature spacecraft designed to accomplish an asteroid flyby mission. A concept for a 3kg microspacecraft and an associated launch strategy are presented.