2409. Addressing Uncertainty in Weight Estimates

Paper

Abstract

At the conceptual design stage, parameters used for weight estimating are subject to significant uncertainty. One can choose to ignore uncertainty or attempt to address uncertainty in some fashion. This paper describes a methodology to explicitly address uncertainty related to a weight estimation task. The methodology utilizes expert judgment to quantify uncertainty associated with weight estimation parameters. A risk analysis is then possible utilizing the data generated by the methodology. An example case for a launch vehicle design is evaluated. Results from the risk analysis are expressed as a range of estimates or a cumulative probability distribution for the estimated value. Results in this form that may be useful for other downstream users such as cost estimating. The primary elements of the methodology were validated by a group of weight estimating/conceptual design engineers. The methodology proved to be a practical and useful technique for addressing uncertainty. Other issues related to the practicality of the methodology and the usefulness of the methodology are discussed in the paper.