以撓褶式機構實現之新型六自由度電磁致動精密定位平臺

A Novel 6-DOF Electromagnetic Precision Positioner Utilizing Flexure Mechanism

吳兆開(Zhao-Kai Wu)

指導教授 ： 傅立成

共同指導教授 ： 陳美勇(Mei-Yung Chen)

國立臺灣大學/電機資訊學院/電機工程學研究所/碩士(2006年)

https://doi.org/10.6342/NTU.2006.00809

摘要

本論文提出一種新型、長行程、六自由度運動的精密定位平臺，用於長行程與精密定位之雙重需求的應用範疇。在本論文中，對於硬體機構設計、電磁致動器設計以及高效能的控制器設計都有完整的介紹。平臺主體係採用一體成型之平行撓摺式機構作為無乾摩擦力的導引機構；致動器系統採用各四組水平與垂直方向之電磁致動器來驅動平臺以達成六自由度運動;量測系統則是採用六組高精度光學位移量測器作為平臺位置訊號之回授。此定位系統期望達成三大目標：第一、擁有長行程的移動能力(此指公厘的範疇);第二、高精密定位的能力;最後，達到快速反應的需求。
本論文所設計的平臺之最大行程可達2mm×2mm×0.5mm，且定位解析度為10μm，平臺整體尺寸為150mm×150mm×20mm。在此系統中，共有八組永久磁鐵黏附在可移動的載台上，以及相對應的八個電磁鐵安裝在固定的基座上。本論文之整體控制架構描述如下：首先，利用六個位移量測器可得知平臺姿態資訊，再藉由調整電磁鐵的電流值以達到控制平臺六自由度姿態運動之目標。再者，在本論文中，為滿足系統強健性及穩定性之雙重目的，並確保定位及追蹤時平臺之六自由度運動皆能符合系統性能之要求，我們提出具強健適應性之可適性滑動模式控制器，在系統參數變化以及外在雜訊干擾之不確定因素下，能順利達成系統之控制目標。經由一連串令人滿意的模擬與實驗結果中，可以證實本論文所設計之六自由度精密定位平臺可以達成長行程、高精度以及低成本之目標。

關鍵字

平行撓摺式機構 ； 電磁致動器 ； 可適性滑動模式控制器 ； 精密定位 ； 六自由度定位器

並列摘要

A novel, six degree-of-freedom (DOF) compact positioner with large travel range and high resolution is proposed for precise positioning application. The precise positioner is composed of monolithic parallel flexure mechanism, horizontal and vertical electromagnetic actuators, and optical displacement sensors to achieve the 6-DOF motion. The concept of the system intends to achieve three goals: 1) large travel range, 2) high precision positioning, and 3) fast response. In our system, there are eight sets of permanent magnets attached to the moving platform, and eight sets of electromagnets mounted on the bottom platen. The whole control architecture is to take the six posture data measured by the six optical displacement sensors first and then to control the 6-DOF motion by regulating the current in the electromagnetic actuators. For the purpose of system robustness and stability, an adaptive sliding-mode controller is proposed to validate the system performance. The developed robust adaptive control architecture consists of two components: 1) sliding mode controller, 2) adaptive law. From the simulation and experimental results, satisfactory performances of the hereby developed system, including stiffness and precision, have been successfully demonstrated.

並列關鍵字

Parallel flexure mechanism ； Electromagnetic actuators ； Adaptive sliding-mode controller ； Precision positioning ； 6-DOF positioner

參考文獻

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