兩軸不匹配增益轉角循跡輪廓誤差控制之研究

王肇璋(Chao-Chang Wang)

指導教授 ： 林榮信

國立中正大學/工學院/機械工程學系/碩士(2014年)

摘要

隨著工具機發展越來越精良，如何提升加工精度以及加工效率成為首要改良的議題。加工時常見的誤差來源有:伺服延遲所導致的轉角輪廓誤差、各軸增益不匹配所造成的穩態輪廓誤差、背隙以及摩擦力等。
本論文主要探討工具機加工轉角時，因機台的伺服延遲與各軸增益不匹配所造成的轉角輪廓誤差與線段穩態輪廓誤差。傳統上欲改善工具機切削誤差，多為更改內部控制器參數為主，但過程較為繁複，需要花費較多時間才能將機台調整到較理想的狀態。本論文提出不匹配刀具路徑補償法，在不更動控制器內部參數以及保持轉角不減速切削的情況下，事先計算出機台伺服延遲誤差與線段穩態輪廓誤差，補償在原有的加工路徑中，藉由改變刀具路徑的方式，來改善轉角輪廓誤差與穩態輪廓誤差，並提升加工效率。
由機台實際擷取路徑資料驗證，以進給速率為2400(mm/min)加工正六邊形時，平均轉角輪廓誤差由0.2385mm降低為0.0108mm，改善倍率達95.47%；線段穩態輪廓誤差由0.0318mm降至0.0199mm，改善效率為37.48%。

關鍵字

刀具路徑 ； 轉角輪廓誤差 ； 伺服延遲 ； 增益不匹配

並列摘要

With the development of more sophisticated machine tools,how to improve the machining accuracy and processing efficiency is the primary issue.The common sources that makes contour errors includes machining system servo lag,the steady-state contour error caused by mismatched axial servo gains,backlash and friction and so on.
This thesis focuses on the corner machining,the tracking contour errors due to machining system servo lags and the steady-state contour error caused by mismatched axial servo gains.In traditional,to improve the cutting errors,mostly change the internal controller parameters,but the process is more complicated,it takes more time to adjust the machine to an ideal state.In this thesis,we hereby developed mismatchd tool-path compensation method,which improved corner tracking contour errors without modifying the controller parameters and reducing the machining feedrate.Calculate the axial servo errors and steady-state contour error in advance,compensate into the original machining tool trajectory,by changing the way to improve the corner tarcking contour error and steady-state contour error,and also improved the processing efficiency.
From the data of the actual path imformation retrieving by the machine,this method is demonstrated that a hexagon cutting experiment,in the situation of mismatched axial servo gains,with feedrate 2400(mm/min).The results shows that the average corner contour error can reduced from 0.2385mm to 0.0108mm,improve the ratio of 95.47%,line steady-state contour error can reduced from 0.0318mm to 0.0199mm,improve the ratio of 37.48%.

並列關鍵字

mismatched axial servo gains ； machine tool path ； corner contour error ； servo lag

參考文獻

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