Stability prediction method for real-time hybrid test system based on the measured dynamics of physical test system

Abstract

The stability analysis of real-time hybrid test (RTHT) is crucial for the division of numerical and physical substructures, performance evaluation of loading system controllers, and feasibility judgment of RTHT systems. Existing stability analysis methods involve the parameter identification and numerical modeling of physical test systems. In contrast, an RTHT involves conducting a physical test on the hard-to-model part. Therefore, it is difficult to accurately model the physical substructure as well as the loading and acquisition systems. In this study, an RTHT stability prediction method based on the measured dynamics of the physical test system was developed, which avoid the tedious numerical modeling of the physical test system. The effectiveness of the stability prediction method was verified through numerical simulation and the experimental testing of a multi-degree-of-freedom shaking table RTHT. The experimental results showed that the accuracy of the developed stability prediction method was higher than that of the model-based stability prediction method by 35.1 %. The stability prediction method developed in this study simplifies the stability analysis of RTHT and will help determine the feasibility of test in advance.