本研究針對使用線性馬達的大負載雙推龍門平台進行超高精度定位技術的研發。此平台除了必須達到奈米水準的硬體定位精度極限以及到位擺動極限外，也必須能進行明確、流暢的連續式微步定位，包括持續不間斷的單格步進定位。同時，即使平台上之負載具有動態平移及轉動運動，平台偏轉角仍須維持在次弧秒以下。針對這些需求，本研究完成了以下的成果：(1) 研發出大功率線性驅動器，以推動大負載進行快速運動。此驅動器除了雜訊極低可滿足奈米定位所需外，同時改進了一般大功率線性放大器的高耗能與熱功耗問題。(2) 針對長距離連續微步定位以及其他實際應用需求，需深入解析摩擦力的動態行為，並根據二個接觸面間接觸點之材料特性與冷銲作用機制建立新的摩擦力分析模型。藉由長期大量的數值模擬與實際實驗驗證，此模型除了展示出目前所發現在各種運動條件下的摩擦力定性行為外，也指出了一些與目前摩擦力觀念相違背的現象，以及新的現象。透過數值模擬與實驗結果，我們也得以明瞭在各種定位條件，包含長距離連續微步定位時的摩擦力行為，以及產生機制，這是建立系統理論模型與擬訂定位控制策略的關鍵。(3) 將龍門平台之運動解耦為平移與旋轉，並分別對此兩運動進行控制。這種做法使得位置與偏轉角的性能表現與各自控制律參數的關聯性更明確，參數調整變得直接，這在控制實務上是非常重要的。
經由反覆長時間驗證，在定位精度與到位擺動量上，實驗平台已達到系統硬體允許的極限(± 4nm)。長距離連續微步定位與單格步進定位的穩定平順表現也都與預期相符，同時偏轉角在所有測試中皆能保持在0.6弧秒以內，在穩態時更能達到0.01弧秒以下。

This research is intended to develop positioning techniques for a dual-drive linear motor gantry stage carrying a heavy load. It is required that this stage not only can do positioning with nanometer precision, but also that it maintains the smallest in-position vibration. Furthermore, it must have the ability to do successive micro-step positioning including successive count-by-count positioning in a positive, smooth and responsive way. In the meantime, the yaw angle of the stage must be maintained at under a sub-arc-second even if the load is moving and rotating on it. In order to fulfill these requirements, a lot of issues have to be studied. However, the following achievements have been attained. (1) A linear driver that can generate a large amount of power to manipulate a heavy load has been developed. This driver does not have the heat dissipation problem of a traditional large power linear driver. More importantly, the noise of this driver is very small, so it is capable of doing positioning with ultra-precision. (2) To fulfill the special requirement that the table should be able to do successive micro-step positioning for a long distance smoothly, the friction dynamics are studied in depth. For this purpose, based on the material properties of contacting asperities, a model is built to simulate the friction mechanism. It has been shown that this model can exhibit qualitative behaviors of friction observed during the pre-sliding phase, slipping phase and the phase in between. Furthermore, some new phenomena that contradict well-known concepts are also revealed. Although these phenomena are not in evidence, they are the key issues to achieve ultra-precision positioning. This model also elucidates how the friction evolves during the process of successive micro-step positioning from the mechanical point of view. Knowing this is crucial for designing control strategies for this case. (3) By dividing the stage motion into translation and rotation parts, a decoupled control strategy is adopted in this research; stage positioning and yaw motion regulating are executed separately. With this kind of control scheme, it is much easier to tune the gains to adjust the system performance and to achieve stringent precision specifications. This tuning capability is very important from the point of view of a controlled engineering practice. All these works have been extensively and repeatedly verified using the gantry stage designed for this research. The nanometer positioning precision and in-position vibration have reached the limit that this system can possibly achieve. The successive micro-step positioning and count-by-count positioning are functioning as expected. The yaw angle of the stage is less than 0.01 arc-seconds at steady state and is 0.6 arc-seconds entire positioning process.

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B. Conference Proceedings
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C. Book
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D. Dissertation/Thesis
Chang, Po-huai (張博懷). 2006. "運用有限元素法設計單軸短行程微奈米定位系統." 碩士論文, 國立台灣科技大學.
Chou, Po-Huan (周柏寰). 2011. "智慧型同動控制之龍門式定位平台." 博士論文, 國立東華大學.
Ko, Ming-Hsien (柯明賢). 2005. "同軸向雙線型馬達同步運動控制之設計與實現." 碩士論文, 國立成功大學.
Lin, Wei-Ming (林緯明). 2007. "雙線型馬達同動工具機之追蹤控制研究." 碩士論文, 國立成功大學.
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D. Product catalog/Datasheet
Aerotech Inc. 2015, Product catalog, internet website http://www.aerotech.com/product-catalog/gantry-system.aspx. (USA)
Rockwell Automation Inc. 2006, Datasheet of Hercules Series Gantry. (USA)
Soonhan Engineering Corp. 2006, Product Catalog (Korea)