Analysis of liquid-type proof mass under oscillating conditions

Abstract

In this study, the spring constant of an accelerometer with a liquid-type proof mass was analyzed. Unlike a general solid-type microelectromechanical system accelerometer, the Laplace pressure is considered a restoring force in the analyzed accelerometer. Using a base excitation mathematical model, the sensor output could be estimated for a specific spring constant. Although the estimated sensor output data fit well with the experimental results, the spring constant of the device could also be determined dynamically (for oscillations below 5 Hz). Moreover, the damping constants could be inferred depending on whether sandblasting treatment was performed. Finally, the effects of the oscillation, surface condition, and volume of liquid metal droplets on the spring constant were analyzed.