The Structure Design And Processing Technology Of High Sensitivity Butterfly Micro-Gyroscope

The micro gyroscopes have brought big changes for the modern war and the people's daily life. But due to the limitation of the structure, getting high-performance micro gyroscope is always a difficulty.Based on the butterfly gyroscope developed by our own laboratory as the research object, this dissertation proposes a novel method to improve its sensitivity. The content includes:1. The research background and respectively researches the foreign and domestic methods of improving the performance of the micro gyroscope are introduced. In the last, the dissertation summarizes the commonly used methods of improving the gyroscope's sensitivity.2. Based on the butterfly gyroscope, the hexagon section oblique beam is used firstly. The mechanics characteristics of the beam and the influence law between the oblique beam structure size and the modal resonance frequency difference are deeply analyzed. The relationship between the model resonant frequency difference and the gyroscope sensitivity is obtained by steady state response analysis. Finally this dissertation puts forward a novel method by designing reasonable size of the butterfly gyroscope oblique to increase the sensitivity.3. Through the theoretical analysis and simulation, the oblique beam size is finally determined. Then the article expounds the important processing technologies of butterfly gyroscope prototype, including the precision time-controlled multilayered pre-buried masks and laser trimming.4. This dissertation studies how the different errors of butterfly gyroscope processing affect the modal frequency difference. The main errors include silicon thickness error, double-side alignment error and the change of environmental temperature.5. The performances of butterfly gyroscope are tested. The experimental results show that the frequency differdnce is about 45 Hz, the scale factor reaches 18.7mV/°/s, which is about 8 times larger than the non-tuned gyroscopes, and the bias stability reaches about 0.85?/h, which is better than 1.64?/h of the non-tuned. Experiment validates the method proposed in this paper can effectively improve the sensitivity of butterfly gyroscope.