Application of an optimization methodology for multidisciplinary system design of microgyroscopes

Microgyroscopes integrated with micro-transducers, readout and control circuits in a common board normally form complex microsystems. Optimization of the design of such systems requires thorough understanding of the coupling effects of their working environments, their physical structural parameters, their construction of electronics, and their fabrication processes, etc. prior to any design verification by costly and time-consuming prototyping. A tuning fork gyroscope was taken as an example to demonstrate the principle for optimizing the necessary multidisciplinary design procedures in designing MEMS, typically including: the environmental quality factors, structural properties, readout circuits, and fabrication factors. It then used genetic algorithm (GA) to optimize the global sensitivity by a specifically designed searching methodology. The so obtained optimal results were further verified by a FEM modal analysis and by an experiment with an acceptable resolution.