3786. Incorporating Non-Random Mass Properties Uncertainties



John Nakai: 3786. Incorporating Non-Random Mass Properties Uncertainties. In: 82nd Annual Conference, Cocoa Beach, Florida, pp. 74, Society of Allied Weight Engineers, Inc., Cocoa Beach, Florida, 2023.



Mass properties uncertainty analysis is used to compute uncertainty intervals for a system’s mass, center of mass, moments of inertia, and products of inertia. These uncertainty intervals are typically defined as plus and minus confidence level ranges about the mean (or predicted nominal) value. A comprehensive mass properties uncertainty analysis involves an assessment of all the factors that can cause variations of the mass and distribution of mass in the system. This assessment requires the Mass Properties Engineer to consider all the potential error sources, how each error source could affect the system, and how to properly combine the uncertainties of the system’s components to compute the total system’s mass properties uncertainties. This paper discusses both random and non-random sources of mass properties uncertainties. It presents examples of various manufacturing, economic, and environmental factors to consider, and discusses how to identify and characterize the types of uncertainties these factors may cause. Methods and algorithms to account for both random and non-random mass properties uncertainties in a system are presented.