摘要
提出了一种基于细分曲面等距面变形的逼近等残留高度刀轨生成算法。利用Catmull-Clark细分曲面具有的逐步逼近的多分辨率特性和误差公式,根据加工误差确定细分次数,并以此作为目标曲面生成等距曲面;根据等距面上点的曲率半径和倾斜角度确定变形率,利用其1-环领域得到变形系数并生成等距面的变形曲面,采用截平面法计算得变形后的刀轨,利用变形系数将刀轨进行逆变形得到原空间上的刀轨。实例证明:该算法在陡峭区域走刀间距变小,刀具路径变密,保证了加工精度。
A tool path planning method of constant scallop-height based on Catmull-Clark subdivision surface was proposed. With an efficient error estimating formula, one can predict how many steps of subdivision were necessary to meet a user-specified error tolerance without subdividing actually. Using the limit points, the normal vectors of subdivision mesh and the radius of the milling cutter, an offset surface was produced. The deformation surface was generated in accordance with the deformation coefficients, which were computed by the slope and the curvature of the offset surface. The tool path which was computed by slicing the deformed offset surface was inversely deformed by those deformation coefficients to a tool path with constant scallop-height. Two examples are used to demonstrate that the machined quality is much better than that of iso-planar machining. The results show that the tool step-over become smaller and the tool-path become closer in steep regions.
出处
《机械科学与技术》
CSCD
北大核心
2009年第9期1143-1146,共4页
Mechanical Science and Technology for Aerospace Engineering
基金
国防基础科研项目资助
关键词
细分次数
变形系数
变形曲面
等残留高度
刀轨路径
subdivision depth
deformation coefficients
deformed surface
constant scallop-height
tool path
