Dual Shaker Testing for Large Test ArticlesApril 27, 2018
Demand for large force shaker testing is increasing, particularly for our clients in the aerospace and satellite sectors. Large electrodynamic shakers like the T4000 are the workhorses of the NTS dynamics labs, but when the test article is so large that it simply will not fit on a large single shaker; our dual shaker systems provide a cost effective, and often better solution.
Advancements in multi-shaker control technology have made multi-shaker, single axis testing more practical, eliminating the concerns with asymmetrical dynamic responses and phase shifts which are a common with large and unbalanced loads. Multi-output control systems employ independently attenuated drive signals which provides a superior test control of a single drive magnitude which was not ideal for an unbalanced load.
Larger test articles can have large overturning moments caused by non-symmetrical loading or resonances in the fixture or test article, an additional benefit of dual shaker testing is that the two shakers can act to restrain overturning moments.
A dual shaker system can achieve equal or greater force and frequency range than a single large shaker and often mitigates the need to band split, resulting higher quality test results and profile characterization.