中点误差控制刀位算法的改进

Improvement of Middle-point-error-control Tool Path Generation Method

中点误差控制刀位算法通过引入抬刀量的概念,将刀具抬离曲面极小的距离,然后调整前倾角与侧偏角以提高刀具与曲面的贴合程度来获得较大加工行宽。文中提出一种将刀触点处侧偏角进行预处理的方法,以避免因一行刀轨内侧偏角不光顺带来的刀轨波动问题。首先对曲面进行分析并选取采样点,然后对采样点处进行刀位优化算得最优侧偏角,以采样点处侧偏角值构造侧偏角二维渐变模型,通过该模型可以计算曲面上任意刀触点处的侧偏角,再通过优化抬刀量和前倾角实现刀触点处行宽最大化。以某航空发动机叶片叶身曲面为例进行了刀位优化。实验结果表明,该方法生成加工刀轨较光顺,证实了该算法的有效性。

Cutter lifting amount is introduced in middle-point-error-control tool path generation method in this paper. Cutter is lifted a tiny distance from the surface, the incline angle and tilts angle are adjusted to achieve a wider machining width. This paper presents a method which can pretreat tilt angle to avoid the fluctuation of tool path due to the ram- smooth tilt angle on tool path. Firstly, we analyze the surface and select the sample points, then calculate the optimal tilt angle via the optimization of tool position on sample points where the gradual model is established. By calculating the tilt angle on every tool position, the uplift amount and incline angle is well-optimized to gain the maximum width on the tool position. This method is verified through generating the smooth tool path of a blade of an aero-engine.