Measurement of large harmonic vibration amplitudes

Abstract

The greater the linearity of a transducer, the more suitable it is for vibration measurement. However, purely linear transducers are not available. It is very common to only use a transducer in a narrow range, where its converting characteristic is close to linear. Unfortunately, only a low signal level can thus be obtained. Therefore, the use of linear features in the measurement process causes non-linear distortions as well as a low signal-to-noise ratio. In this paper, a method for measurement of harmonic vibration amplitudes is presented that allows one to eliminate the above drawbacks. This method allows the extension of the range available for vibration measurement. It could be used, for example, in measurement of standing waves, calibration of devices, etc. This method also gives the ability to obtain maps of the vibration amplitudes with increased surface resolution. © 2003 Elsevier Ltd. All rights reserved.