Dynamic Multi-Axis Calibration of MEMS Accelerometers for Sensitivity and Linearity Assessment

A set of triaxial MEMS (Micro-Electro-Mechanical Systems) accelerometer, of commercial type, has been calibrated on a test bench, which is based on a rotating table. The bench has been designed for this specific purpose and it allows to calibrate contemporaneously all accelerometer measuring components, by realizing accurate reference accelerations in the frequency range 0 to 8 Hz. A working model of the calibration set-up and procedure is described to realize a complete and detailed uncertainty budget of the reference and of the sensor accelerations. Experimental uncertainty assessment of all the accelerometers has been carried out, allowing to obtain all the linearity and sensitivity data, accelerometer by accelerometer, axis by axis. Data processing has been carried out and interesting information is get about the level of uncertainty which is achievable, depending on the way the calibration data are evaluated, taking into account or not differences of sensitivity data for each other accelerometer and/or considering differences among measuring components of a single accelerometer.