Description_of_the_Experiment

3.2.1.2 Description of the Experiment

To observe the inherent static frequencies of circular saw blades, two saw blades – one full saw blade with diameter D = 300 mm, thickness of 2 mm, and one saw blade with two apertures with diameter D = 300 mm and thickness of 3 mm – were used.

The observed saw blades were firmly fixed in the flanges of the fixture. The position of the fixture with the saw blade mounted in the holographic table is displayed in Fig. 3–22.

To excite the saw blades we used the electro-magnetic exciter mounted on the back side of the fixture. The detection of resonance frequencies was realised by the real-time holographic interferometry where the interference fringes were adjusted to the finite fringe width obtained by displacement of the fixture in the vertical axis direction.