Theoretical Analysis of Stiffness Constant and Effective Mass for a Round-Folded Beam in MEMS Accelerometer

In this paper, the governing equations of stiffness constant and effective mass for a round folded suspension beam in Micro-Electro Mechanical System (MEMS) accelerometer are derived and solved. The stiffness constant is determined by the strain energy and Castigliano’s displacement theorem, whereas the effective mass is determined by the Rayleigh principle. The stiffness constant and the effective mass are solved separately by components and then combined by using the superposition method. The results obtained by the derived equations agree well when compared with the finite element results for several thickness values. The governing equations derived in this paper can be used to predict the natural frequencies and sensitivity of the MEMS-accelerometer