摘要
为解决目前国内飞机蒙皮等自由曲面零件在机加工过程中无法精确定位的问题,在理论层面对其自定位方法进行了研究,即运用基于ICP(最近点迭代)算法的两级定位策略进行定位,达到精确求解定位矩阵的目的。该策略在粗定位时从工件CAD模型匹配至初始点云数据,精定位时从粗定位点云数据匹配至工件CAD模型。提出了一种精定位采点策略,有效地解决了ICP算法的匹配集合包含问题;建立了匹配算法的优化目标函数,并应用切平面法进行求解,通过仿真模拟验证了该定位策略和迭代算法的精度和可靠性。该方法可以指导蒙皮件在机加工中实现工件自定位。
Aimed at solving the difficulty of positioning the titanium aircraft skin precisely in machining process, self-positioning method was theoretical studied and thus a two-level localization method based on ICP（Iterative Closet Point） was proposed, in which the CAD model was matched to point cloud at coarse matching and the point cloud was matched to the CAD model at fine matching. A policy for mining points at fine matching, which effectively solved the inclusion problem between matching sets in ICP algorithm, was proposed. This thesis established an optimization objective function of matching algorithm, solved the function with the method of cutting plane, and finally, validated the accuracy and reliability of the positioning strategy and iterative algorithm with the help of simulation. This method can guide the skin pieces to achieve self-positioning in machining process.
出处
《模具技术》
2014年第2期6-9,22,共5页
Die and Mould Technology
关键词
飞机蒙皮
自由曲面
自定位
ICP算法
aircraft skin
freeform surface
self-positioning
ICP algorithm
