A Description Of Nbs Calibration Services In Mechanical Vibration And Shock

A description of NBS calibration services in mechanical vibration and shock

A Description of Nbs Calibration Services in Mechanical Vibration and Shock (Classic Reprint)

Excerpt from A Description of Nbs Calibration Services in Mechanical Vibration and Shock There are two principal categories of measurement used in the calibration of accelerometers and reference exciters at the National Bureau of Standards: comparison and absolute. When the calibration factor is obtained directly from a measurement of quantities which form the base units of a system of units, the calibration is called absolute The comparison method involves simultaneous measurement of the outputs of the transducer under test and a reference transducer of known and stable characteristics, with both devices subject to the same excitation. The comparison method has been implemented by constructing a vibration exciter with a built-in or attached transducer and a space for mounting an accelerometer to be tested. A test accelerometer can be readily calibrated by direct comparison of its voltage to that of a standard. The comparison method is very simple and relatively inexpensive, compared to the absolute methods of calibration, which can be very time consuming. This survey document describes the methods of calibrating vibration pickups by comparison with nbs standards, including a special shock calibration service, and absolute methods used primarily in the calibration of the reference standards. A summary is given of the various calibration procedures, beginning with the comparison calibration procedures using electrodynamic, air-bearing, and piezoelectric exciters which cover the low, mid, and high-frequency ranges, respectively. A shock calibration service which employs analog-to-digital converters and fast Fourier transform analysis to calibrate a test accelerometer in terms of a reference accelerometer is then described. The last section describes the absolute calibration procedures which are primarily used to calibrate the reference exciters and accelerometers. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.

Handbook of Noise and Vibration Control

Two of the most acclaimed reference works in the area of acoustics in recent years have been our Encyclopedia of Acoustics, 4 Volume set and the Handbook of Acoustics spin-off. These works, edited by Malcolm Crocker, positioned Wiley as a major player in the acoustics reference market. With our recently published revision of Beranek & Ver's Noise and Vibration Control Engineering, Wiley is a highly respected name in the acoustics business. Crocker's new handbook covers an area of great importance to engineers and designers. Noise and vibration control is one largest areas of application of the acoustics topics covered in the successful encyclopedia and handbook. It is also an area that has been under-published in recent years. Crocker has positioned this reference to cover the gamut of topics while focusing more on the applications to industrial needs. In this way the book will become the best single source of need-to-know information for the professional markets.