CNC五軸加工機B-spline切削指令應用研究

A study on Application of B-spline Cutting Command on 5-axis NC Machine

陳裕霖(Yu-Lin Chen)

指導教授 ： 蔡哲雄

國立臺北科技大學/機電學院/機電整合研究所/碩士(2008年)

https://doi.org/10.6841/NTUT.2008.00045

摘要

目前在CAD的設計大都是以自由曲線與曲面(NURBS、B-spline、Bezier曲線與曲面)來做為設計的依據。部份CNC控制器的NC-code如G06.2、BSPLINE指令已經可以承接這些數學參數式。使用B-spline指令可以解決線性插值法程式過多與因刀具執行單節直線切削指令結束時的減速動作，在加工路徑上造成切點的不連續的問題。本文以Matlab建立B-spline數學模型，對B-spline曲面做刀具切削路徑規劃，主要是將等參數法所求得的CL-data轉換成相對應B-spline的NC-code應用於三軸加工。然而大部分對於B-spline指令的處理僅限於三軸，很少是針對於五軸B-spline的處理。因此本文應用Siemens 840D控制器新式NC指令(ORICURVE)五軸加工的表示方法，對五軸側銑B-spline曲面做路徑規畫及加工程式設計，並於CNC五軸加工機台(Siemens 840D控制器)實作驗證。

關鍵字

Nurbs曲線 ； B-spline NC指令 ； 刀具路徑 ； 五軸加工

並列摘要

The Free-form curves and surfaces, such as NURBS (Non Uniform Rational B-Spline), B-spline, or Bezier, can be treated by most of CAD systems. Some NC controllers can handle NC data written in NURBS interpolated formula such as BSPLINE, NC code from Siemens controller, and G06.2 for Fanuc controller. The use of NURBS expression enables us to decrease the amount of NC data, to eliminate the error due to the linear interpolation and to get rid of rapid acceleration and deceleration. The paper using MATLAB to create B-spline mathematical surface model for B-spline tool path computation. According to CL-data (Cutter Location data) calculated from iso-parametric method, we could obtain corresponding data of B-spline NC code. However, less CAM systems can create NURBS interpolated NC data for 5-axis controlled machine tools. Therefore, this article also uses the new 5-axis B-spline NC-code, ORICURVE, on SIEMENS controller for 5-axis tool path computation and machining tests.

並列關鍵字

Nurbs curve ； B-spline NC-code ； Tool path ； 5-axis machining

參考文獻

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