Modal Electrodynamic Shakers
Modal shakers are used in the study of vibration behavior of structures. No test specimen is mounted on such shakers. These shakers are mounted to the structure with a stinger and force is transferred from the shaker to the structure via this stinger. The structure under test and/or the modal shaker can be hung with components such as an elastic rope or spring during the test to simulate free-free boundary conditions. In this way it is possible to excite the test sample at different frequencies. As a result, the natural frequencies and mode shapes of the structure can be calculated with the vibration values measured over the structure.