Calibration of tri-axial MEMS accelerometers in the low-frequency range – Part 1: comparison among methods

Abstract

Abstract. Two alternative experimental procedures for the calibration of tri-axial accelerometers have been compared with traditional methods, performed according the procedures stated in the standard ISO 16063-21. Standard calibration is carried out by comparison with a laser Doppler vibrometer (LDV), used as a primary reference transducer. The main sensitivities have been investigated and, where applicable, also transverse ones. Many aspects have been evaluated: the hypotheses about transverse sensitivities, the simplicity of the procedure, the number of measurements needed, and the effect of typology of transducer, depending on electrical and geometrical contributions. Two different accelerometers have been tested, a piezo-electric accelerometer and a capacitive MEMS accelerometer. A low-frequency range of vibration has been investigated, 3 and 6 Hz, with amplitude of acceleration ranging from 2 to 20 ms−2. A satisfactory reproducibility of methods has been verified, with percentage differences less than 2.5 %. Anyway, pros and cons of each method are also discussed with reference to their possible use for easy and quick calibration of low-cost tri-axial accelerometers.

Self-Made Tri-Axial Accelerometer Design Considerations for Validation of Simultaneous Multi Axis Accelerometer Calibration System

“…A multi axis calibration system based on [7], Method 2, was implemented and investigated at NMISA. Method 2 involves the simultaneous excitation of the three axes of the accelerometer under test.…”

A Review of the Capacitive MEMS for Seismology

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Reduction of calibration uncertainty due to mounting of three-axis accelerometers using the intrinsic properties model

“…However, the CCAUV’s key comparisons do not currently support tri-axial accelerometers. Towards this end there has been recent work by Prato et al [ 1 ] and others [ 2 , 3 ] in developing vibration calibration methods for tri-axial accelerometers based on vibration measurements for the simultaneous determination of main and transverse sensitivities in the frequency domain. Prato et al employ an inclined mount for the accelerometer that is placed on a shaker.…”