Architecting Lunar Surface Exploration Systems using a Decision-based Approach
- Paper number
IAC-08.D1.3.8
- Author
Dr. Willard L. Simmons, Massachussets Institute of Technology (MIT), United States
- Coauthor
Mr. Wilfried Hofstetter, Massachussets Institute of Technology (MIT), United States
- Coauthor
Mr. Paul Wooster, Massachussets Institute of Technology (MIT), United States
- Coauthor
Prof. Edward Crawley, Massachussets Institute of Technology (MIT), United States
- Year
2008
- Abstract
NASA is currently engaged in developing a systems architecture for human exploration of the Moon as planned in the Vision for Space Exploration. This systems architecture includes surface habitation, surface mobility, power generation and management, and the lunar lander. The designs of these systems are strongly interrelated and there are a variety of applicable figures of merits, leading to a large design space from which it is difficult to evaluate and select design alternatives. This paper describes a novel approach for analyzing systems architectures by explicitly representing architecture as the result of a set of interconnected decisions. The paper shows that this approach provides useful insight in the architecture space for the lunar surface exploration system. The problem is modeled as a set of decision variables connected by constraints and property functions in the form of an Architecture Decision Graph (ADG). Each decision variable indicates a set of mutually exclusive architectural alternatives for the surface architecture. The constraints capture that certain combinations of decision variable assignments are incompatible. The property functions evaluate the performance of each set of decision variable assignments with regard to figures of merit. ADG’s simulation algorithm is used to enumerate and evaluate the space of feasible architectural configurations. The results include two measures of potential decision variable impact: the potential impact on system properties and the potential impact on other decision variables. These two measures give insight into how to prioritize architectural decision-making tasks. In particular, decision variables such as the existence of an intermediate outpost capability, whether the capability for pressurized connections exists, and whether habitats are offloaded from their landers to the lunar surface are shown to be significantly impactful. Therefore, we conclude that these decisions should be given a high-priority in the architecting process. Other decision variables, such as what communications strategy is utilized or whether or not there is a capability for long-sortie missions are found to be less impactful on the architecture space. We conclude that these decisions should be given a lower priority in the architecting process.
- Abstract document
- Manuscript document
(absent)