Uncertainty characterization under measurement errors using maximum likelihood estimation: cantilever beam end-to-end UQ test problem

Abstract

One goal of uncertainty characterization is to develop a probability distribution that is able to properly characterize uncertainties in observed data. Observed data may vary due to various sources of uncertainty, which include uncertainties in geometry and material properties, and measurement errors. Among them, measurement errors, which are categorized as systematic and random measurement errors, are often disregarded in the uncertainty characterization process, even though they may be responsible for much of the variability in the observed data. This paper proposes an uncertainty characterization method that considers measurement errors. The proposed method separately distinguishes each source of uncertainty by using a specific type of probability distribution for each source. Next, statistical parameters of each assumed probability distribution are estimated by adopting the maximum likelihood estimation. To demonstrate the proposed method, as a case study, the method was implemented to characterize the uncertainties in the observed deflection data from the tip of a cantilever beam. In this case study, the proposed method showed greater accuracy as the amount of available observed data increased. This study provides a general guideline for uncertainty characterization of observed data in the presence of measurement errors.