Digital Twin Output Functions and Statistical Performance Metrics for Engineering Dynamic Applications

One of the most common uses of digital twins is to provide information to a user to aid in the decision-making process. The process a digital twin undertakes to generate information can be considered a digital twin output function. These can involve predictive simulations, historical trends, and other types of analysis using the data gathered directly from the physical twin and the models contained within the digital twin. Because of this dependency on model simulations and gathered data, the concept of trust is highly relevant to the development of digital twins. To evaluate the trust of a digital twin, specifically the quantitative aspects, the calculation of uncertainty and performance metrics is vital. This chapter considers how performance metrics can be used to compare the output functions of a digital twin to the measured quantities of interest in the physical twin, and thus provide additional information to establish trust in the digital twin that aids in decision-making. This approach will be demonstrated using an engineering dynamics example related to vibration testing.