Hidden diffusion processes of two-inertia systems

Two-inertia systems are an important model in most industrial applications. It contains the actuator and load parts. For applications, such as position or velocity controls, due to coupling engagement, the discrepancy between the actuator and load is expected. Usually, this difference is unobservable. In this paper, we employ the hidden diffusion process to model the effects between the actuator and load, which is coupled by a flexible shaft. The hidden process is modeled by probability and has its expectation. Crucial theories are given for evaluation and verification. Based on the proposed methodology, four theoretical findings are given to show the effects of the hidden process in a two-inertia system. These results are useful for applications in which the actuator and load of an operation process, which reveals the hidden stochastic behaviors.