Abstract
The present paper examines a method for the design of a spatial filter for suppressing modal observation spillover. A type of modal filter was proposed for eliminating several selected modal amplitudes from structural vibration responses. This filtering methodology can be realized by a small number of sensors, relative to the number of dominant modes in the frequency range of interest. The proposed filter can be designed using sensor placement to realize that the two subspaces, which are respectively spanned by a spatial filter vector and the selected target modal vectors, are orthocomplementary. The observation modal spillover associated with these selected modes is then suppressed. The effectiveness of the proposed filter was verified numerically for a cantilever beam and simulation results demonstrated potential for suppressing spillover in vibration control and health monitoring.
