環形陀螺儀模態振形之研究

Modal Analysis of Ring Gyroscope

盧志誠(Jr-Cheng Lou)

指導教授 ： 周傳心

共同指導教授 ： 謝發華

國立臺灣大學/工學院/應用力學研究所/碩士(2009年)

https://doi.org/10.6342/NTU.2009.10202

摘要

陀螺儀的發展至今已數十年，由於一個對稱元件在高速旋轉下，其方向不會改變的特性因而被廣泛應用於飛機、艦艇及衛星等軍事用途上，至現在更發展應用於汽車及電玩等民生工業；而陀螺儀的種類也由初期轉子式陀螺儀演變成現今振動式或光纖式陀螺儀。
不同於傳統轉子式陀螺儀，振動式陀螺儀具有使用期限較長且啟動時間短等優點；因而現行所使用及研究的陀螺儀多以振動式陀螺儀為主；振動式陀螺儀其結構上的設計形式也分為許多種類，包括音叉式、樑式及半球殼等，本研究中之陀螺儀以金屬圓環為主體，由壓電材料來驅動及感測，探討陀螺儀振動之振型及模態分析；進而讓此陀螺儀達到持振與節點抑制，以利將來可使用力平衡方式判定角速度與感測電壓間的關係。
根據實驗的結果，可以確定其第一共振頻率模態及此環的第一共振頻率數值，於此研究中並且利用設計之回授電路讓此環形陀螺儀達到持振與抑制節點振動，而往後也將使持振及抑制節點的振動頻率一致並減少雜訊的干擾，方便未來使用力平衡方式來檢測角速度訊號。

關鍵字

模態 ； 振動 ； 回授電路

並列摘要

Research of Gyro has been developed for many years. It is used on airplane、ship and satellite for military affairs a long time ago then now it is applied to car or game industry and kinds of gyro evolved from rotor gyro into vibrating gyro or fiber gyro.
The paper primarily study vibrating gyro because that can improve restrictions of rotor gyro including life and time of switch. There are all kinds of vibrating gyro include tuning fork gyro, rod gyro and hemispheres, and in this paper, the study main apply metallic ring which is driven and sense by piezoelectric material. So it can make the vibrating gyro vibrate without input signal and restrain vibrating in the node which can use force-balance method to check angular velocity between voltages in the future.
According to experiment result, it can make sure the first natural frequency of the vibrating ring-gyro and design feedback circuit to let the ring vibrate without inputting signal in the first natural frequency and restrain to vibrate in the node. From the result, the metallic ring can achieve my demands. It must improve signal in the circuit and reduce affect from noise which will make for sensing angular velocity between voltages with force-balance method in the future.

並列關鍵字

modal ； vibrate ； feedback circuit

參考文獻

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