This project provides equipment, the MASSCOMP data acquisition and signal processing system, for support of structural dynamics research. Two projects, entitled Energy Flow in Mechanical Systems, and Wavenumber Processing Techniques will utilize the equipment. The first project addresses a set of unresolved structural dynamics issues. These include the ability to model structures with closely spaced modes whose resonant bandwidths overlap in the frequency domain, and damping mechanisms at structural interfaces. This project uses both a three dimensional space truss and a plate or shell like structure supported on a grid or truss system. Securing useful data requires placing arrays of twelve accelerometers at two locations on the structure. Twenty four simultaneous channels of data can thereby be acquired and processed by the MASSCOMP system. The second project focuses on developing practical experimental techniques for studying the phenomenon of mode conversion. This occurs when flexural motion associated with one mode in one part of a structure couples with longitudinal motion associated with a different mode in an adjoining part of the structure. The method used here is the spatial frequency or wavenumber processing technique. It also requires taking simultaneous samples of structural deformation data from an array of accelerometers and then processing the data through the MASSCOMP system.
