Modeling and Simulation of MEMS-Based Comb Drive Actuator for Development of Single Axis Gyroscope, Using Bond Graph

Abstract

Abstract-A comb drive is an important component of MEMS-based actuators used in many applications such as a dispenser and a fluidic pump, and as a sensor in an accelerometer and in MEMS gyroscope. These energy systems, generally called mechatronic systems, are coupled multi-domain. Modeling and simulation of mechatronic systems is a challenging task. For coupled multidomain energy systems recently Bond Graph Method (BGM) has emerged as a method of choice. The system is seen as an interplay ofpower and energy variables, thus introducing the immortal concept of cause and effect. The two primary forces, electromechanical and electrostatic, are cast into the cause and effect paradigm whilst expressing power into effort and flow variables. In this research work the main focus is on the investigation of the control parameters of laterally vibrating electrostatic comb-drive actuators. 20-SIM, a commercial bond graph package, is used to investigate the influence of control parameters on performance of the comb drive. The design process of system-on-chip (SoC) MEMS can be improved by this type of analysis. The comb-drive is represented here as a main source of actuation which is vibration in lateral direction. The work can be used as any design application as a cooling system for microprocessors used in space vehicles or a drug delivery system based on fluidic pump in on-a¬chip systems. The multi-physics system of a robust comb-drive is modeled and solved using the 20-SIM, a commercial bond graph software. In this model, the driving voltage is taken into account. The comb drive displacement and electrostatic force are in direct relation to the square of the driving voltage. In this method, a model based on BGM is developed and then directly simulated using 20-SIM (a commercial software of Bond Graph modeling). Since bond graph is a precise mathematical model, the state-space equations of physical dynamic system can be solved. The bond graph simulations lead to the desired state space equations, which unfold the dynamic response of the physical system.