疊代學習控制技術應用於五軸輪廓循跡控制

Iterative Learning Control Technology for Five-Axis Contouring Control

蔡秉寰(Bing-Huan Tsai)

指導教授 ： 林明宗

國立虎尾科技大學/工程學院/機械設計工程研究所/碩士(2013年)

https://doi.org/10.6827/NFU.2013.00013

摘要

本論文提出一五軸命令式疊代學習控制技術(Five-axis command-based iterative learning control, FCILC)結合使用刀具中心點控制功能(Tool center point control function, TCPCF)，用以大幅提升五軸重複輪廓加工之追蹤以及輪廓循跡性能。在不改變CNC運動控制器架構下，FCILC學習演算法利用前幾次加工程序的追蹤誤差來疊代更新輸入命令。此TCPCF技術可偵測刀具位置以及刀具軸向路徑之尖銳轉角以及不連續處，並依據切線以及軸向急衝度的限制來產生平滑之五軸命令軌跡。FCILC技術則可降低由系統伺服落後以及摩擦力所造成之追蹤及輪廓誤差，並消除外部雜訊的累積效應。最後，將此FCILC結合一零相位濾波器應用於一搭載PC-based控制器之擺頭搖籃型五軸雕刻機上，實驗結果顯示採用FCILC技術五軸刀具中心點之輪廓循跡精度可以被大幅地提升。

關鍵字

疊代學習控制 ； 五軸輪廓循跡 ； 輪廓誤差 ； 刀具中心點控制

並列摘要

In this paper, a five-axis command-based iterative learning control (FCILC) with tool center point control function (TCPCF) is proposed to improve the tracking and contouring performance for five-axis repetitive contour machining. Without changing the original CNC control architecture, the proposed FCILC utilizes the learning algorithm to updates the input commands based on the tracking errors from the previous process. The TCPCF can detect the sharp corner and discontinuity of the tool position and orientation, and generate smooth five-axis motion trajectories based on the constraints of tangential and axial jerk. The FCILC can reduce the tracking and contouring errors caused by servo lag and friction, and alleviate the effects of noise accumulation. Finally, FCILC with a zero-phase filter is applied to a C-type five-axis engraving machine using a PC-based controller. Experiment results validate that the contour errors of the TCP can be significantly reduced using the proposed technology.

並列關鍵字

Iterative learning control ； Five-axis contouring ； Contour error ； Tool center point control

參考文獻

[1]L. Andolfatto, S. Lavernhe and J. R. R. Mayer,“Evaluation of servo, geometric and dynamic error sources on five-axis high-speed machine tool,” International Journal of Machine Tools and Manufacture, vol. 51, no. 10-11, pp. 787-796, 2011.

[2]M.-T. Lin, M.-S. Tsai and H.-T. Yau, “Development of a dynamics-based NURBS interpolator with real-time look-ahead algorithm,” International Journal of Machine Tools and Manufacture, vol. 47, no. 15, pp. 2246-2262, 2007.

[3]Z. Qiao, T. Wang, Y. Wang, M. Hu and Q. Liu, “Bezier polygons for the linearization of dual NURBS curve in five-axis sculptured surface machining,” International Journal of Machine Tools and Manufacture, vol. 53, no. 1, pp. 107-117, 2012.

[4]A.-C. Lee, M.-T. Lin, Y.-R. Pan and W.-Y. Lin, “The feedrate scheduling of NURBS interpolator for CNC machine tools,” Computer-Aided Design, vol. 43, no. 6, pp. 612-628, 2011.

[5]X. Beudaert, S. Lavernhe and C. Tournier, “Feedrate interpolation with axis jerk constraints on 5-axis NURBS and G1 tool path,” International Journal of Machine Tools and Manufacture, vol. 57, pp. 73-82, 2012.