當軸承以流體作為主要能量傳遞媒介時，可稱該系統為一液壓軸承，相較於採機械接觸元件作為技術核心的傳統軸承，液壓軸承往往具備更佳的精度、剛性及更長的生命週期，然而，相對昂貴的造價與繁雜的設計流程使其技術在國內仍不甚普及。舉例來說，液靜壓軸承對於環境溫度及供油壓力的變化較為敏感，需引入精密感測器及控制元件穩定操作環境，增加不少除軸承本體之外的設計製造成本。
通常，液靜壓軸承會外接一套液壓調節裝置作為供壓來源，藉由將油體打入靜壓腔內形成一高壓薄油層，並利用油腔壓力所產生的承載力使軸體浮升。然而，本研究發現，由於傳統供油系統往往不具備流量補償機制，是以在軸承參數設計階段視為定值的供油壓力，亦可能隨外界負載變化而不同，最終導致液靜壓軸承無法操作於穩定的環境中，甚至影響其剛性與精度表現。
為解決上述問題，本文採用電磁比例壓力閥作為主要壓力調控裝置，藉由即時監控回授訊號，迅速地補償油壓，期望壓力變動幅度盡可能地縮小。在控制系統方面，本研究利用dSPACE控制器及ControlDesk軟體，設計液壓調節系統之人機介面，搭配MATLAB識別系統模型與分析動態特徵。待數學模型建立完成後，搭配前饋與反饋等控制策略設計一套雙重迴路架構，利用模擬與實驗方法驗證控制設計，並探討控制前後液壓調節系統的穩壓表現。最後，連接液壓調節系統與液靜壓線性平台，觀察施予負載時系統之穩壓效果及剛性變化。
從實驗的結果中可以看出，相較於傳統供油裝置，加入雙重迴路控制後的液壓調節系統能夠迅速且穩定地追蹤參考訊號，達到穩壓的效果。未來亦可嘗試使用不同的控制方法，或是替換現有的液壓元件與元件間配置方式，進一步優化整體供油裝置的性能，提供液靜壓軸承一個更為穩定的操作環境。

As a system treated fluid as its medium between the slider and the guideway, we used to call it a hydraulic guideway ,or maybe a hydraulic platform. Comparing to those traditional bearings who utilize mechanical-contacted element as its core technology, hydraulic ones often equip better accuracy, rigidity and life cycle performance. However, relatively expensive cost and complicated design process make it not that popular in the country so far. For example, hydrostatic bearings are extremely sensitive to changes in ambient temperature and oil supply pressure, so it is necessary to introduce a large number of sensors and control components to stabilize its operating environment. Inevitably, it will take a lot of extra cost excluding designing and manufacturing.
In common, there is always a set of hydraulic regulators as an oil supply attached to hydrostatic bearings. The oil injected into the chamber will produce a thin oil layer with pressure between slider and guideway. Finally, the pressure difference between each chamber generate bearing capacity to float the slider. However, this study found that the flow rate of traditional oil supply system is far less than the rate of change in flow resistance. The above corollary make the hypothesis that supplied pressure is a constant value set at designing stage invalid consequently.
To solve these problems, in this study, proportional pressure valves had been used as main regulating devices of oil supply system. Using real-time monitoring technique, it is expected that the impact on system rigidity caused by pressure changes will be minimized. With MATLAB/ Simulink to identify the plant model and analyze its dynamic characteristics, this paper used dSPACE as controller and its derivative software ControlDesk to complete the man-machine interface design. Afterward, design inner and outer loop using control methods such as feedforward and feedback. Last but not least, comparing the simulation and experiment performance with each control strategies respectively.
It is obvious that comparing with conventional oil supply devices, the hydraulic adjustment system with double-loop control is able to track the reference signal faster, more accurate, and more stable. It also provide hydrostatic bearings better sources of pressure ,and achieve the above goal of this study as well.

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