Abstract:

Current five-axis linear interpolation method for sculptured surface machining has the drawbacks of low-speed, low-accuracy and large Numerical Control (NC) file. To overcome these drawbacks, a five-axis CNC controller with fairing function for spline curve interpolation was proposed. The construction method of spline curve in this CNC controller and the real-time spline curve interpolation method were introduced. For machining of workpieces with streamline form, before real-time interpolation, fairness judgment of the sequence of cutting tool centre points, provided by CNC file, was carried out. Those tool centre points that did not satisfy the fairness judgment were modified. Machining case demonstrated that the proposed method can avoid all the drawbacks of five-axis linear interpolation method. Application showed that the new CNC controller can achieve good machining results for workpieces with streamline form.

Key words: technology of instrument and meter, five-axis machining, open controller , spline interpolation, fairing function