Study on the Rotational Sensors in Ground Measurement and Application
           

- 指導教授 黃漢邦 博士 研究生 林欽仁

- Advisor :Dr.Han-Pang Huang Student : Chin-Jen Lin

Lab. of Robotics., Department of Mechanical Engineering, National Taiwan University, Taiwan

Abstract:

As progress of rotational sensor, it had been extensively applied to several fields, like aerospace, consumer electronics, robotics, structure monitoring, seismology, etc. There are various rotational sensor technologies available including micro-electro-mechanical, fiber optic gyroscopes, ring lasers, and molecular electronic transducers. Rotational sensor can be classified either low-pass or band-pass systems depending on whether their pass-band reaches DC or not. Different application requires rotational sensor with different specification, e.g. robotics measures rotational motion with rapid and large amplitude, while seismology records slow and tiny ground rotation. Therefore, choosing an adequate rotational sensor to meet various requirements is important.

This dissertation investigates the rotational sensor extensively, including instrument calibration and application. For the instrument calibration, we propose a novel mechanical design of rotational shake table and calibration methodology. We also use AerotechTM ARMS-200TM simulator to calibrate eentecTM R-1TM rotational sensor in detail. We compare array rotation and point rotation, and we point out several advantages from 6 degree-of-freedom (DOF) recordings for teleseismic and near-field earthquake. To prove the theory we proposed, we discuss the rotational motion between array-derived and direct measurement from translational and rotational array in TAIPEI 101, analyze the first 6-DOF ground motion for a teleseismic, and make experiment by attaching 6-DOF sensors on the robotic arm. We also implement the attitude estimator and North finder by using a rotational sensor.

Finally, this dissertation made several conclusions for rotational seismology. We proposed the specification requirement of a strong-motion rotational sensor for seismology, point out the merit that wave direction and wave velocity can be derived from 6-DOF ground measurements at one station, correct rotational effects on accelerometer to derive permanent displacement, and demonstrate that the North finder for finding the true North will not be affected by environment variation.





中文摘要:


隨著科技的進步,旋轉感測器已經廣泛地應用在各個領域,包含航太、消費性電子、機器人產業、結構物觀測、地震觀測…等等。從運作原理來區分,有微機電、光纖、環型雷射、電化學…等等;從頻率響應來區分,有直流型和帶寬型。各種應用領域所需要的規格亦不相同,如機器人運動需要量測快速的旋轉變化,而地震觀測則是量測微小的地動旋轉變化,因此,依照不同的應用,來選擇適合的旋轉感測器是一件重要的事。

本論文旨在對旋轉感測器作全方面的探討,內容包含儀器檢驗及其應用。儀器檢驗方面,本文提出創新旋轉檢驗平台的機構設計及旋轉感測器的檢驗方法,亦利用AerotechTM 公司的ARMS-200TM 旋轉平台,詳細地檢驗eentecTM公司的R-1TM旋轉感測器。應用方面,討論陣列旋轉量與單點旋轉量的差異,並提出對於遠場地震以及近場地震同時觀測其地動平移量以及旋轉量的好處,分別透過擺放於TAIPEI 101的旋轉感測器以及地震儀陣列、所記錄之遠震的六自由度資料、以及機器手臂六自由度量測的實驗,來驗證本論文提出的理論。最後使用旋轉感測器,來實現姿態估測器以及尋北儀兩項裝置。

最後,本文的結論著重於旋轉地震學領域,提出地動旋轉量觀測所需要的儀器規格,說明單站同時觀測地面的平移量以及旋轉量能夠得到地震波的方向、速度等優點,量測六自由度運動能夠修正加速度計的旋轉效應進而得到位移軌跡,以及利用尋北儀來尋找正北方向不會受到環境限制的優點。