NURBS曲线高速高精度加工的插补控制

An Interpolator for NURBS Curve Machining with High-Speed and High Accuracy

针对复杂零件高速精密加工的需求 ,提出了一种 NURBS曲线的实时插补算法 .它基于 NU RBS曲线的矩阵表示 ,通过适当的插补预处理、运用参数预估计与校正的插补策略以及合理的近似计算方法 ,简化了插补的实时计算 ,保证了算法的实时性 .特别是引入了插补误差和进给加速度的实时监控 ,使进给速度能随曲线曲率自适应调整 ,实现了

NURBS has been widely used in CAD/CAM for modeling complex parts. To improve the capability of CNC machines in machining complex parts, modern interpolators capable of generating NURBS curves are required. In this paper a real time interpolator for NURBS curves based on parameter prediction and correction is presented. The proposed approach provides good performance in two respects to meet the requirements of high speed and high accuracy machining. First, the calculation time is significantly reduced by applying preprocessing, avoiding to compute the derivative and radius of curvature of curves. Second, feed rate can adapt to the curve's curvature to limit the contour error and feed acceleration within the allowable range.