五軸工具機加工軌跡動態輪廓誤差分析

Dynamic Contour Error Analyses For Five-axis Machining Trajectory

鄭光筌(Cheng, Guangquan)

指導教授 ： 林榮信

國立中正大學/工學院/機械工程學系/碩士(2012年)

摘要

近年來工業界對五軸CNC工具機加工技術的需求逐漸增加，以達到加工高精度、較少加工時間及複雜幾何形狀的工件。本研究針對五軸加工軌跡動態輪廓誤差與刀具向量誤差加以分析，動態輪廓誤差的主要因素是加工軸對伺服反應延遲造成。同時含旋轉軸的五軸同動比一般線性軸同動產生的更大輪廓誤差，故本研究分析多軸同動輪廓誤差。
本研究使用Matlab編譯程式模擬五軸CNC加工的伺服系統動態行為，並探討五軸工具機中各伺服軸的參數對輪廓誤差的影響，如伺服軸不匹配時，對加工軌跡的輪廓誤差之影響。最後本研究以實際機台實驗來驗證電腦模擬結果，進而分析空間曲線加工的輪廓誤差與刀具向量誤差，並且探討此二項誤差所造成之加工過切量。

關鍵字

加工軌跡 ； 輪廓誤差 ； 工具機

並列摘要

In order to have high precision machining, less machining time, and complex part machining capabilities, the five-axis machining technique has become more and more important in recent years. This research analyzes machining trajectory dynamic contour error and tool orientation error for five-axis machine tools. The major reason for causing contour error is the servo-lag on CNC system. In additions, the five-axis coordinated motion, including rotating axes, produces larger contour error than regular three-axis machine does. Therefore, this research focuses on the analyses for multi-axis coordinated motion contour errors.
This research uses Matlab software to simulate the dynamic behavior for five-axis CNC machining system, and studies the contour error changes due to the servo gain changes. In the end, the developed analysis method is implemented on a five-axis machine tool for verifying the computer simulation results. The result shows the machining contour error and tool orientation error for a real machine. The machining overcut is also analyzed due to these two errors.

並列關鍵字

trajectory ； contour error ； machining

參考文獻

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