9.1.3 Modular Building Blocks for Manned Spacecraft: A Case Study for Moon and Mars Landing Systems

A method is presented for the selection of optimal modular building blocks for platforming of manned Moon and Mars landing systems employing modularity on the subsystem level; platforming shall here be defined as the reuse of designs across different systems. The motivation for platforming is the need to reduce overall Moon and Mars exploration architecture lifecycle cost by lowering spacecraft development, test, and fixed production cost, and to provide flexibility in system design to accommodate changes in the exploration architecture. The fundamental idea is to compute the surplus in functional attributes generated by using particular building block (module) sizes, then relate the surplus to a cost function, and finally select the building block sizes with minimal additional cost. Results are presented for modular crew compartments, propellant tanks, and engines. The proposed method is potentially helpful for platforming decision-making, as well as subsystem technology selection in a broad class of engineering systems.