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Shaker (testing Device)
A shaker is a device used in vibration testing to excite the structure, either for endurance testing or modal testing. References *Tongue, Benson, ''Principles of Vibration'', Oxford University Press, 2001, *Inman, Daniel J., ''Engineering Vibration'', Prentice Hall, 2001, *Rao, Singiresu, ''Mechanical Vibrations'', Addison Wesley, 1990, *Thompson, W.T., ''Theory of Vibrations'', Nelson Thornes Ltd, 1996, *Hartog, Den, ''Mechanical Vibrations'', Dover Publications, 1985, See also * Vibration Vibration is a mechanical phenomenon whereby oscillations occur about an equilibrium point. The word comes from Latin ''vibrationem'' ("shaking, brandishing"). The oscillations may be periodic, such as the motion of a pendulum—or random, su ... Tests {{technology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vibration Testing
Vibration is a mechanical phenomenon whereby oscillations occur about an equilibrium point. The word comes from Latin ''vibrationem'' ("shaking, brandishing"). The oscillations may be periodic, such as the motion of a pendulum—or random, such as the movement of a tire on a gravel road. Vibration can be desirable: for example, the motion of a tuning fork, the reed in a woodwind instrument or harmonica, a mobile phone, or the cone of a loudspeaker. In many cases, however, vibration is undesirable, wasting energy and creating unwanted sound. For example, the vibrational motions of engines, electric motors, or any mechanical device in operation are typically unwanted. Such vibrations could be caused by imbalances in the rotating parts, uneven friction, or the meshing of gear teeth. Careful designs usually minimize unwanted vibrations. The studies of sound and vibration are closely related. Sound, or pressure waves, are generated by vibrating structures (e.g. vocal cords); the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Modal Testing
Modal testing is the form of vibration testing of an object whereby the natural (modal) frequencies, modal masses, modal damping ratios and mode shapes of the object under test are determined. A modal test consists of an acquisition phase and an analysis phase. The complete process is often referred to as a Modal Analysis or Experimental Modal Analysis. There are several ways to do modal testing but impact hammer testing and shaker (vibration tester) testing are commonplace. In both cases energy is supplied to the system with a known frequency content. Where structural resonances occur there will be an amplification of the response, clearly seen in the response spectra. Using the response spectra and force spectra, a transfer function can be obtained. The transfer function (or frequency response function (FRF)) is often curve fitted to estimate the modal parameters; however, there are many methods of modal parameter estimation and it is the topic of much research. I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vibration
Vibration is a mechanical phenomenon whereby oscillations occur about an equilibrium point. The word comes from Latin ''vibrationem'' ("shaking, brandishing"). The oscillations may be periodic, such as the motion of a pendulum—or random, such as the movement of a tire on a gravel road. Vibration can be desirable: for example, the motion of a tuning fork, the reed in a woodwind instrument or harmonica, a mobile phone, or the cone of a loudspeaker. In many cases, however, vibration is undesirable, wasting energy and creating unwanted sound. For example, the vibrational motions of engines, electric motors, or any mechanical device in operation are typically unwanted. Such vibrations could be caused by imbalances in the rotating parts, uneven friction, or the meshing of gear teeth. Careful designs usually minimize unwanted vibrations. The studies of sound and vibration are closely related. Sound, or pressure waves, are generated by vibrating structures (e.g. vocal cords); t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
