REAL-TIME MODAL PARAMETER-ESTIMATION USING SUBSPACE METHODS - APPLICATIONS

This article describes the underlying theory and hardware implementati on of a newly developed algorithm for online modal parameter identific ation. An online modal parameter estimation algorithm using subspace m ethods is applied to both model and experimental data for a 4-m labora tory truss structure. Experimental evaluation of this algorithm demons trates that the technique accomplishes the objective of tracking multi ple modes of a complex dynamical system using multiple sensors. The ti me-varying behaviour is captured in real time via a graphical display of the frequencies and damping ratios of the system. It is shown that the recursive algorithm provides results similar to the batch algorith m for a time-invariant system. In addition, it is shown that the batch algorithm used to derive the recursive algorithm performs similarly t o a newly derived batch algorithm that is closely related to the Eigen system Realization Algorithm. Details concerning the digital signal pr ocessor implementation and off-line monitoring are also presented. (C) 1998 Academic Press.