摘要: |
The Common Habitat is a large habitat that uses theSpace Launch System core stage liquid oxygen tank as itsprimary structure. It has a gravity-independent internalarchitecture, such that identical units can be used on the lunarsurface, Mars surface, and in microgravity. In developing thehabitat, two key architectural questions emerged. Should theinternal layout use a vertical or horizontal orientation of thetank? Should the crew size be four or eight? This led to thedesign of four variants: a four-crew horizontal, four-crewvertical, eight-crew horizontal, and eight-crew vertical. Theprimary consideration applied for down-selection was the crewexperience living and working in the habitat, inclusive of crewproductivity, well-being, and survivability. Based on thisconsideration, a series of seven assessments was performed tocompare the four variants. A stowage assessment developed astandard logistics module and then considered the amounts ofwater to be stored in each variant. It then estimated how muchstowage could be carried onboard each Common Habitat andhow many logistics modules are required by each variant for agiven mission duration. A functional analysis identified andcompared the living and working functions across the fourhabitat, ranking them relative to each other. A crew timeassessment first estimated the total crew time, building a weeklycrew timeline for both four and eight-person crews. It thenallocated time to activities linked to living and workingfunctions, comparing how much time was available for eachfunction in each variant. A science productivity assessmentdeveloped a relative metric using crew time, science stowage,and assumed rates of experiment consumables use toanalytically compare the four variants. It also comparativelyranked the habitats with respect to a number of subjectiveparameters and a workstation acceptability rating. Amaintenance capacity assessment identified and comparedeleven generic maintenance capabilities across the four variantsand also ranked the variants for their predicted ability tocomplete twelve fabrication, maintenance, and repair scenarios.A contingency responsiveness analysis examined twelve seriousin-flight contingencies. For each scenario, the number of crewneeded to respond was predicted and acceptability of variousaspects of contingency response was evaluated, comparing thefour variants against each other. Finally, in a habitabilityassessment, 120 habitability characteristics reflecting 13 majorcategories were evaluated for each habitat. These results werecompared to identify the most acceptable habitat in eachcategory. Ultimately, the data was shown to favor the horizontalorientation over the vertical and an eight-person crew over four.Implications of selecting this variant are discussed, includingspecific architectural challenges that result from the use of thefull SLS liquid oxygen tank. |