基于曲率连续的混合曲线插补方法研究

Research on Interpolation Method of Mixed Curve Based on Curvature Continuity

为了保证数控机床能连续稳定地加工,需要对数控机床的刀具轨迹进行光顺和插值操作。由于加工轮廓的多样性,提出一种基于曲率连续的非均匀B样条和PH曲线混合插补算法。该算法在几何约束条件下,使用非均匀B样条曲线拟合小线段,并在拐角处使用5次PH曲线衔接,进一步提高加工轮廓的光顺性,通过弓高和加速度的限制对速度进行约束,完成平滑光顺的轮廓加工。通过实验对比和验证分析,所提算法相比PH曲线算法,加工效率提高6.5%;相比非均匀B样条算法,轮廓更精确。

In order to ensure the continuous and stable machining of CNC machine tools,it is necessary to smooth and interpolate the tool path of CNC machine tools.Due to the diversity of machining contour,this paper presents a hybrid interpolation algorithm based on curvature continuity for non-uniform B-spline and PH curve.With geometric constraints,the algorithm uses non-uniform B-spline curve to fit small line segments,and uses quintic PH curve to connect at the corner,further improving the smoothness of the processing contour,and constrains the speed through the restriction of bow height and acceleration to complete smooth contour processing.The test results show that,compared with the pH curve algorithm,the proposed algorithm improves the machining efficiency by 6.5%and the contour is more accurate than the non-uniform B-spline algorithm.