Multishaker Broadband Excitation for Experimental Modal Analysis

A new method of excitation for modal testing is described which combines the benefits of the two most often used techniques: multipoint sine dwell and single-point random. This new method--multishaker broadband excitation--employs an array of shakers to develop multiple sets of frequency response functions, which, as evidenced by their reciprocity and consistency, yield a more accurate representation of the structure's dynamics, resulting in a better modal model. Additionally, this new technology offers a significant reduction in time required to perform a modal survey. An example application to the space shuttle orbiter Enterprise is described.