面向STL格式零件规则特征表面点元素拾取及其法向矢量估算方法  

Method of Picking Points on the Surface of Rule Feature and Estimating Normal Vector for STL Format Parts

作　　者：诸进才[1] 胡艳娥[1] Zhu Jincai;Hu Yan'e(School of Electromechanical Engineering,Guangzhou Railway Polytechnic,Guangzhou 510430,China)

机构地区：[1]广州铁路职业技术学院机电工程学院,广州510430

出　　处：《机电工程技术》2022年第12期61-64,共4页Mechanical & Electrical Engineering Technology

基　　金：广东省普通高校工程技术开发中心项目(编号:2019GGCZX008)。

摘　　要：分析了STL格式零件规则特征数字模型作为设计和检测模型的基准应用于接触式检测存在的表面点无法直接拾取和由此带来测点法矢无法精确计算等现实问题。以最常见的平面和孔特征为例,提出了平面和规则孔等规则特征表面测点快速获取策略及其法向矢量估算的方法,以及非规则孔侧壁任意测点的构造及其法矢估算方法,得到的法矢与三维软件法向矢量计算结果的对比结果表明这种方法得到的法矢精度较高,可满足在机检测对测点获取及其法矢精确度的需求。实现了STL格式零件规则特征应用于在机检测的可能,为其他规则特征作为设计模型应用于接触式检测提供了可借鉴的经验。The problems that the surface points can not be directly picked up and the normal vector of the measuring points can not be accurately calculated when the STL format digital model of regular parts was applied to on-machine measurement were analyzed. Taking the point elements on the outer surface of plane & hole features as example, the fast acquisition strategy of regular measuring points and the method of normal vector estimation were proposed. Compared with the calculation results of normal vector by three-dimensional software, it showed that the proposed method has high accuracy and can meet the requirements of on machine measurement for measuring point acquisition and normal vector accuracy. It realizes the possibility of applying the regular feature of STL format parts to on machine measurement and provides reference experience for other regular features to be applied to measurement as digital model.

关 键 词：STL 规则特征 在机检测 法向矢量 

分 类 号：TP274[自动化与计算机技术—检测技术与自动化装置]