The objective of this project is to test the applicability of hierarchical decision model and process developed by Nathasit Gerdsri in his doctoral research in Systems Science/Engineering Management Ph.D. As a test case, the intent of the project is to replicate the decision making process at NASA for selecting the 2nd generation Reusable Launch Vehicle (RLV) technology known as the Orbital Space Plane (OSP) concept. There are three OSP concept alternatives currently under consideration. The alternatives each have unique design characteristics. To conduct a formal evaluation of the alternatives, the team quantified subjective judgments formed on the basis of conceptual, preferential and qualitative information gleaned from NASA and related sources. Six main decision criteria, selected from NASA Level-1 Requirements, are dissected into sub-criteria, defined by Gerdsri as factors, and weights are quantified for each factor by subjectively judging relative magnitude of importance using the principles of multicriteria decision making [1]. Each factor is then scaled from 0 to100 using the straight method of ratio scaling. Six different descriptive ranking continuums are used for the scale. The score of each scaled factor indicates the condition of the alternative relative to the factor. All combinations of the six main criteria are compared pairwise with each other with respect to relative importance. The multicriteria method allowed us to weight and score factors, and pairwise comparison provided a means to rank the relative importance of each main criterion. The result of the combined methods is a value indicating the optimal choice of the three OSP alternatives. This study is a hypothetical scenario based on actual concept designs and current events.
Note: The presentation associated with this report is included here as a supplemental file
