精微工具機之機上精密刀具定位系統改良及體積誤差檢測與補償系統之研究

Improvement of an On-Machine Tool Positioning System and Volumetric Error Measurement and Compensation for Micro Machine Tools

林志俊(CHIH-CHUN LIN)

指導教授 ： 王世明

中原大學/工學院/機械工程研究所/碩士(2009年)

https://doi.org/10.6840/cycu200901604

摘要

Non-MEMS精微加工技術已被視為是精密工業發展的重要關鍵項目之一，然而微型工件與微刀具不易準確定位，無法有效檢測與補償精微工具機的體積誤差，則是影響精微加工技術普及應用於產業上的重大瓶頸之一。本研究發展出具複合功能且可直接安裝於微型工具機上之非接觸式機上微型刀具定位與體積誤差檢測及補償系統，並透過靈敏度分析了解各誤差源對檢測精度的影響。微型刀具定位功能主要是利用Power Law Method強化影像和應用Canny Edge Method及影像投影法來準確辨識工件輪廓邊緣，以兩個CMOS即可檢測出微工件/微刀具的起始定位誤差。再透過自行發展的NC碼自動編譯系統產生一誤差修正NC程式，經由執行該NC程式，則微型刀具可被準確的定位以進行切削。體積誤差檢測及補償功能則是應用Canny Edge Method和齊次座標轉換法，結合使用標準校正模板來直接量測精微工具機的三維體積誤差，再利用此量測法支援建立Element Free Method所需的節點體積誤差資料庫，並結合Element Free Method、遞迴式誤差補償法和NC碼自動辨識與撰寫系統，則可對規劃的切削路徑進行誤差預測與補償。最後，也於研究室所開發的微型工具機上進行實機驗證，結果證明該二系統確實可提升微型工具機的加工精度。

關鍵字

誤差補償 ； 機上檢測 ； 微刀具定位 ； 體積誤差 ； 誤差預測

並列摘要

Non-MEMS micro machining technology has been regarded as one of the key technologies for the development of precision industry. However, difficulties in positioiung the micro cutter and in measuring the volumetric errors of a micro machine tool restrict the implementation of this technology to industry. An on-mahcine error measurement and compensation system that can accurately position a micro tool and meausure/compensate volumretric errors of a mcro machine tool was developed in this study. Sensitivity analysis was also adopted to analyze the influences of major error sources on the measurement accuracy. With using 3 COMSs, Power Law Method, Canny Edge Metho, and image projection method were adopted to develop the function of micro tool positioning. The initial positioning error of a micro tool can be inspected by the system and compensated through executing a NC program generated by the NC-code writing unit. With Canny Edge Method, Homogeneous Transformation Method, Element Free method, and use of the resolution targets, the volumetric error measurement method was developed and used to measure the volumetric errors at nodal points for Element Free Method. With integration of Element Free Method, the recursive error compensation algorithm, and the NC-code identifying and writing unit, the machining trajectory errors can be predicted and compensated. Experiments were conducted to verify the effectiveness of the developed system. The experimental have shown that the system can effectively improve the maching accuracy of a micro machine tool.

並列關鍵字

error compensation ； error prediction ； volumetric error ； micro tool positioning ； on-machine measurement

參考文獻

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