Noise characteristics of sensors for extreme low level vibration measurements

Abstract

Performing vibration assessment of structures and sites having stringent vibration requirements poses problems for vibration measuring equipment routinely used for measurements of vibrating structures for modal analysis. When vibration levels are required to be of the order of one micron per second or less, special consideration has to be given to the whole of the instrumentation chain for data acquisition and it is necessary to establish the performance limits of available sensor systems. This means devising methods for testing and presenting the noise characteristics of equipment and providing meaningful specifications of noise characteristics when using a third party for vibration assessment. Experiences are presented in using seismometer and a range of accelerometers for a number of low level structural vibration measurements.