Abstract: Dynamic model issues of micro electromechanical systems (MEMS) with electrostatic field coupling are studied. Firstly, input/output model with two terminal pairs of electrostatic field is given. Selection and analysis method of independent variable pairs for MEMS are discussed. Secondly, two typical micro structures, which are developed in our lab, including SEM photos, vibration modals of finite element analysis, and simplified model, are described, Thirdly, The electrostatic field and its force expressions, dynamic equations, and open loop & close loop transfer functions of MEMS sensors are analyzed. Fourthly, The frequency responses and equivalent model parameters obtained from tests are given, and some significant conclusions are presented based on the results of analysis and tests mentioned above.

Key words: Dynamic model, Electrostatic field coupling, Micro electromechanical systems