Hardware Double-Integration for Acceleration to Displacement Conversion with MEMS Accelerometers Under Harmonic Excitation

The accurate measurement of displacement is essential for assessing the performance and the safety of various mechanical systems. One promising approach to achieve this is the use of accelerometers and double integration of the signal to convert acceleration data to displacement. MEMS-type accelerometers are highly sensitive and compact devices that are widely used for measuring acceleration. This study explores hardware-based acceleration-to-displacement conversion by using microelectromechanical system accelerometers under harmonic excitation. A hardware system for double-integration, employing operational amplifiers, has been designed. The well-known equations that relate these two quantities have been also used. High-pass filters have been implemented between each conversion stage in order to avoid errors caused by the signal drift. Vibration tests have been performed by using a closed-loop controlled electrodynamic shaker, and an inductive sensor served as the position reference. Results show that hardware integration is well suited for reliable position measurements, whereas it has been observed that mathematical conversion consistently overestimated velocity and displacement, particularly at low frequencies.