本文研究目標主要在於討論如何改良液壓滑台之摩擦力對定位精度的影響，改良方式可以設計低摩擦硬體與控制補償。本文所設計的低摩擦油壓伺服滑台，是以使用聚四氟乙烯(PTFE)滑動密封的油壓缸並以線性滑軌以便達到油壓滑台的低摩擦目標，經由量測滑台於各種工作條件下之摩擦特性與多點定位控制實驗結果，本文所設計之低摩擦滑台相較於一般油壓滑台於各項響應性能均較佳，但是在達到目標點以後易因中位飄移發生滑動。根據系統摩擦特性，對低速運動時易發生之黏滯摩擦設計補償訊號。由實驗結果可知，無論最大靜摩擦增益補償或是顫震訊號的控制器均可使一般的滑台也能達到1μm定位精度。

The purpose of this paper is to discuss how to improve the position accuracy effect by the friction force. The improving methods can be designing a low-friction hardware and compensation in controller. The hydraulic slider designed in this paper is with the PTFE slipper-seal and linear guide so it can achieve the low-friction goal. After measuring the friction force of the slider in each kind of working condition and multi-point positioning, the control performance of the slider designed in this paper is better than the general hydraulic slider, but when the slider reaches the goal position, it slips easily because of the null point draft. According to the friction character of the system, we can try to design the compensation signal for the stick friction due to the low working velocity. In the result of the control experiment, the controller with either the max static friction compensation or the dither signal can let the general slider achieve 1μm position accuracy.

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