Reducing Risk of Large Scale Space Systems Using a Modular Architecture

摘要

Future requirements may dictate the need for very large spacecraft architectures. At present, the only approach to placing large spacecraft into orbit is use of a heavy lift launch vehicle. But, given the new capabilities demonstrated by NASA's DART, and DARPA's Orbital Express, RASCAL, and FALCON, it is reasonable to envision an alternative means of placing large spacecraft into orbit, that being multiple responsive launches of discrete modules which are later assembled on orbit. An analysis was performed to compare the risks and benefits of single large spacecraft launch versus a multiple small module launch approach. The results of this probabilistic analysis show that fragmenting a system into modules can significantly reduce the deleterious cost and schedule impact incurred by possible failures. In short, a single launch of a monolithic spacecraft poses significant risk; should failure of a large spacecraft launch occur, the penalty is the significant sum total of both launch and spacecraft costs.