Une méthode de calibration simultanée des accéléromètres et des pots vibrants dans le plan transversal

Abstract
The cross-axis sensitivity of accelerometers that is of the order of a few hundredths of the main axis sensitivity, is a common concern in vibration measurements. Usually the manufacturers do not provide a complete information upon the transverse sensitivity of transducers. The transverse motion of mechanical shakers is subject to the same problem and lack of information. The method that we present here is aimed at calibrating at the same time both defaults relatively to the axial components. By mounting an accelerometer on a shaker so that the main motion is perpendicular to the main sensitivity, its response adds up two products of the same order of magnitude : the main motion x the cross-axis sensitivity and the main sensitivity x the transverse motion. These two quantities are separated when the accelerometer rotates around the main-motion axis. All relative components of transverse motion and cross-axis sensitivity are derived from a combination of orientations of the accelerometer relatively to the main-motion axis. Measurements made with a variety of accelerometers exhibit a good consistency of the results concerning the transverse motion of a given shaker. Conversely, a good reproducibility of results pertaining to the cross-axis sensitivity of accelerometers has been achieved. The range in which that method is easily used with good results is limited in the low-frequency region by the motion of the shaker base and attachment.