微機電陀螺儀之設計與實現

Design and Implementation of MEMS Vibratory Gyroscopes

任頡(Ren, Jye)

指導教授 ： 李昇憲

國立清華大學/工學院/奈米工程與微系統研究所/碩士(2015年)

摘要

本研究包含微機電陀螺儀的設計、模擬、製作與量測，並且分別從結構及整體系統的角度探討設計理念、各項參數與應用規格之關係。本研究利用台積電CMOS-MEMS整合平台下線，設計濾波感測模態陀螺儀(Filter-Sensing Mode Gyroscope, 簡稱FSMG)，預期能同時保有較大頻寬及較高敏感度；本研究也以SOI製程設計、製作環耦合陀螺儀(Ring Coupled Gyroscope, 簡稱RCG)，此陀螺儀在同尺寸中能有較大的電容傳感面積，並保有環結構的優勢，如：抗加速度、振動的能力，以及先天頻率匹配的特性，具有潛力應用至下一代陀螺儀。製作完成之環耦合陀螺儀之共振頻位於約135 kHz，兩共振頻之差異最小為13 Hz，達成∆f/f≅0.0096%之結果。在真空、空氣中的Q值分別約為3000-10000、30-60。本研究也以運算放大器開發了用於控制與量測微機電陀螺儀之印刷電路板，RCG搭配此電路板達成驅動模態的自我振盪，並且在旋轉平台上於常溫、常壓量得之敏感度為2.2 mV/°/s，而Angle Random Walk為15.8°/√hr。

關鍵字

陀螺儀 ； 微機電 ； 濾波感測模態 ； 環耦合

並列摘要

This work reports the design, simulation, fabrication, and measurement of MEMS vibratory gyroscopes. The relationship between specification and parameters is also discussed from the viewpoint of the whole system. The first design, Filter-Sensing Mode Gyroscope (FSMG), based on TSMC’s MEMS Platform can reach larger bandwidth with sufficient sensitivity. The theory shows that the parameters in FSMG are not sensitive to the environmental damping coefficient. Moreover, the tuning fork structure in FSMG provides better shock resistance and error reduction. The robustness makes FSMG very suitable for automotive applications. The second design based on an SOI fabrication process is also developed. Ring Coupled Gyroscope (RCG) takes advantages of the symmetric ring structure, while increasing the transduction areas. This design makes the ring structure without increasing its size or reducing its transducer’s gap to achieve satisfactory capacitive coupling coefficient. By adopting the in-plane and n = 3 mode, the resonant frequencies (i.e., driving and sensing modes) of RCG are inherently matched. Therefore, it has great potential for the next generation gyroscopes. The fabricated RCG has the smallest frequency split as ∆f/fres≅0.0096% at the resonant frequency of 135 kHz. The quality factor is about 3000-10000 in vacuum and 30-60 in air, respectively. The PCB for the proposed gyroscope is also designed for control and measurement purpose. The driving loop with AGC is achieved. The measured sensitivity is 2.2 mV/°/s, and the angle random walk is 15.8°/√hr.

並列關鍵字

Gyroscope ； MEMS ； Filter-Sensing Mode ； Ring Coupled Mode

參考文獻

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