Six-axis accelerometer based on diamagnetic levitated resonator exploiting a coplanar capacitive sensing scheme

Abstract

The presence of wear, friction, and material stiffness limits the robustness and sensitivity of traditional accelerometers with mechanical connections between the base and the proof mass. The diamagnetic levitation system can achieve stable levitation at zero energy consumption and offers mechanical isolation between the magnet base and the levitated mass. Its intrinsically low stiffness makes it promising for the development of better accelerometers. In this project, an accelerometer is designed based on a diamagnetically levitated resonator that consists of a two-by-two magnet array in checkerboard layout and a 10×10×0.3 〖mm〗^3 pyrolytic graphite plate. The accelerometer explores a coplanar capacitive sensing scheme and achieves readouts with σ = 66.84 aF. The accelerations in all six degrees of freedom can be extracted with the results of FEM simulation and experiments. For the in-plane translation mode, it has a sensitivity of 30.28 fF/m∙s^(-2) and a resolution of 6.63e-3 m /s^2. Performances are also carefully characterized in static and dynamic scenarios. Being the first 6-axis levitation accelerometer, it verifies the great potential of the diamagnetic levitation system in the development of a high-performance functional device and indicates the feasibility of using coplanar capacitors for measurement of levitated objects.