Measurement of natural vibrations of multi-degree-of-freedom systems with large damping by multi-point excitation using local feedback control

This study aims to develop a measurement method for natural vibrations of multi-degree-of-freedom systems with large damping. A design and condition monitoring of machines and structures based on physical models is usually used. The 1DCAE concept and digital twin using physical models have been developed for rapid design processes and condition monitoring. Here, parameters of a physical model of a large-scale structure with a large vibration damping system are difficult to identify from experimental measurements. The authors developed a measurement method for natural vibrations using multi-point excitation with local feedback control. In this paper, the influence of the number and locations of excitation points for measurement accuracy of natural vibrations of large-scale structures with large damping is investigated. First, an overview of the multi-point excitation method with decentralized control using local feedback is introduced. Next, the measurement accuracy of natural vibrations with a fully actuated system with local feedback control is investigated. It was confirmed that measurement accuracy of natural vibrations by local feedback control is high.