Accelerometer transverse sensitivity calibration; validation and uncertainty estimation

The National Metrology Institute of South Africa (NMISA) has implemented a system to measure the transverse sensitivity of vibration transducers. As a mechanical device, the principle sensing axis of an accelerometer is not 100 % perpendicular to the mounting axis. This gives rise to the effect that the accelerometer will produce an electrical output even when a mechanical input perpendicular to the principle measurement axis is applied. The quantification of this "defect" parameter is of importance when high accuracy acceleration measurements are performed using accelerometers. This paper gives a brief overview of the system developed by the NMISA to measure the transverse sensitivity of vibration transducers. The paper then explores the validation of the system along with the uncertainty of measurement associated with the calibration system.