基于走刀矢量优化的五轴加工路径设计

发布时间：2018-02-02 04:40

本文关键词： 复杂曲面矢量法刀具轨迹数控加工　出处：《大连理工大学》2016年硕士论文　论文类型：学位论文

【摘要】：目前,虽然传统汽车发展受到限制,着力发展新能源汽车,但是汽车覆盖件和汽车模具的发展仍然是汽车工业中不可小觑的部分。数控加工在工业生产中占据主导地位,复杂形状的零件和模具的加工依赖于数控加工,其过程是相当耗时。高质量的数控加工刀具轨迹对减少加工时间和提高加工质量有重要作用。针对目前多轴数控加工刀具轨迹设计方法存在的轨迹零散、重叠大和轨迹光滑性问题,论文提出了一种基于运用B样条基函数构成的流函数进行五轴数控加工刀具轨迹优化的矢量方法。论文基于给定的点云数据在参数域上进行刀轨的优化。首先采用插值法进行自由曲面的重构,接着将构建的三维曲面进行均匀采样,形成离散数据点并计算出每个采样点处优化的走刀方向。然后,在参数域进行刀具轨迹规划。包括走刀方向在参数域内的表达,运用流函数进行参数空间上的矢量场逼近和选择等值线方式规划出参数域上的刀具轨迹模型。最后,将参数域上的轨迹映射到原来曲面上,形成原来加工曲面的刀具的刀触点轨迹。根据选择的刀具参数对刀触点轨迹进行偏置,而形成刀位点轨迹并将其生成的文件导出,以便于进行数控加工的NX仿真。论文的整个算法过程都是借助于VS2010软件,使用C++语言、MFC等,对上面的算法进行了实现。论文中,采用平底刀建立计算模型,推导出有效加工轮廓计算公式,并计算出流函数值和等值线值,从而生成了刀具轨迹,将该轨迹导入NX,借助NX CAM进行了数控加工的仿真。结果显示,用矢量法规划出的刀具路径轨迹较为光滑、连续、整齐。
[Abstract]:At present, although the development of traditional vehicles is restricted, efforts to develop new energy vehicles. However, the development of automobile panels and dies is still an important part of the automotive industry. NC machining plays a leading role in industrial production, and the machining of parts and dies with complex shapes depends on NC machining. The process is very time-consuming. High quality NC machining tool path is important to reduce the processing time and improve the machining quality. Aiming at the current multi-axis NC machining tool path design method the trajectory is scattered. The problem of overlap and smoothness of trajectories. In this paper, a vector method of tool path optimization for five-axis NC machining based on the current function of B-spline basis function is proposed. The tool path is optimized in the parameter domain based on the given point cloud data. The free form surface is reconstructed by interpolation method. Then the constructed 3D surface is uniformly sampled to form the discrete data points and the optimized path direction at each sampling point is calculated. Then. The tool path planning is carried out in the parameter domain, including the expression of the cutter direction in the parameter domain. The vector field approximation in parameter space and the selection of isoline are used to program the tool path model in the parameter domain. Finally, the trajectory on the parameter domain is mapped to the original surface. According to the tool parameters selected, the cutter contact trajectory is biased, and the tool locus trajectory is formed and the generated files are exported. In order to facilitate the NX simulation of NC machining, the whole algorithm process of this paper is implemented with the help of VS2010 software and C language. The calculation model is established by using the flat-bottom cutter, and the calculation formula of the effective machining contour is deduced, and the value of the flow function and the isoline are calculated, thus the tool path is generated, and the trajectory is imported into NX. The simulation of NC machining with NX CAM is carried out. The results show that the path path is smooth, continuous and neat.
【学位授予单位】：大连理工大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：U466

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