参数曲线的自适应插补算法

摘要

参数曲线插补是高性能CNC系统实现复杂轨迹控制功能的重要技术基础。文中提出了一种CNC系统参数曲线的实时插补算法，基于参数预估、误差控制及参数校正的策略，实现了参数曲线的高精度快速插补。理论分析与仿真表明，该算法与现有的插补算法相比，不仅速度误差小、实时性好，而且插补速度能随曲线曲率的变化自适应调整，确保加工精度达到给定要求。此外，本算法具有良好的实现通用性，可以适用于样条等各种参数曲线。%To improve the capability of CNC machines in handling complex parts, modern interpolators in CNC systems are required to be capable of generating curves. In this paper a real-time interpolation algorithm for parametric curves in CNC systems is presented,which interpolates parametric curves by applying parameter predicting, error controlling and parameter correcting. In contrast to the existing interpolators, the proposed algorithm can result in smaller feed-rate errors, require less computing time, and can be implemented less dependent on the curves. Particularly, the accuracy of the interpolator is monitored in real-time, and the feed-rate adapts with the curvature of curves to limit the contour errors in the desired values, which can satisfy the interpolation requirements of high accuracy machining with high speed.