Physical Parameter Estimation of Non-classically Damped Systems from Spatially Incomplete Modal Parameters

摘要

In this paper, an approach is developed to identify the physical parameters of a class of non-classically damped systems in the situation of incomplete instrumentation, i.e., when not all active degrees of freedom (DOFs) of the system are instrumented (excited/observed). The proposed method starts with the initially identified spatially incomplete complex modes, and sequentially considers each row of the complex eigenvalue problem, to estimate the complete set of physical parameters, along with the complete complex mode shapes. It is shown that only two consecutively instrumented DOFs are theoretically sufficient for identifying the complete set of physical parameters. The proposed method is validated using a numerical example, also considering the effect of noise in the initially identified modal parameters.