面向局部点云信息缺失的模型重构方法  

Research on Model Reconstruction Methods for Partial Point Cloud Information Loss

作　　者：常正平[1] 袁国帅 李玖桦 赵阳 王仲奇[1] CHANG Zhengping;YUAN Guoshuai;LI Jiuhua;ZHAO Yang;WANG Zhongqi(School of Mechanical Engineering,Northwestern Polytechnical University,Xi’an 710072,China)

机构地区：[1]西北工业大学机电学院,陕西西安710072

出　　处：《工程科学与技术》2025年第2期54-63,共10页Advanced Engineering Sciences

基　　金：陕西省自然科学基础研究计划项目(2024JC-YBMS-318);国家自然科学基金项目(52475539,52175450)。

摘　　要：面向新一代航空航天型号高性能制造需求,基于实测数据的性能预测方法愈来愈得到广泛应用。然而,受限于零件尺寸大、结构遮挡多和设备性能不足等问题,该方法难以获得零件完整的实测数据,影响了产品性能预测精度。为此,提出面向局部点云缺失的模型重构方法,构建扫描区域与点云缺失区域的拓扑关系,求得缺失区域的表面点集。首先,提取理论3维模型表面几何信息,并将其转换至拉普拉斯坐标系;其次,将扫描点云数据进行划分,结合粗配准与迭代最近点(ICP)精配准算法进行区域匹配,得到理论模型上与扫描点云对应的区域;然后,采用拉普拉斯网格变换使匹配区域驱动理论三角网格发生形变,并用扫描点云替换对应区域,得到零件完整点云。最后,以飞机起落架外筒为例,采用传统方法与本文方法进行对比,发现当扫描点云覆盖达到一定范围时,所提方法的最大偏差为0.145 mm,显著低于传统方法的0.717 mm,验证了该方法在重构模型精度上的提升。Objective With the increasing demand for improved assembly performance,conducting assembly performance analysis based on measured data has become increasingly important.At the present stage,assembly performance analysis requires model refactoring to predict assembly errors.The refactoring of a model of point cloud inverse reconstruction can reflect real physical information,which solves the deviation between simulation and actual results.However,large-sized and structurally complex parts face challenges such as blocks,which result in incomplete point cloud information.Therefore,the overall surface point cloud of the part cannot be fully obtained,preventing the refactored model from accurately representing real physical information.Therefore,research on model reconstruction methods without local point clouds is essential.This study proposes a Laplace mesh transformation method to deform the theoretical triangular mesh based on the scanned area.The corresponding region of the theoretical model is replaced with the scanned point cloud to obtain a complete point cloud of the part.Methods The theoretical model and the scanned area point cloud were used as data sources.The triangular mesh formed by the scanned region point cloud and the surface of the theoretical model constituted a two-dimensional manifold reference domain,ensuring that any point selected from the reference domain had a corresponding mapping in the triangular mesh.Then,the Laplacian mesh transformation was applied to achieve mesh mapping.This process utilized the Laplacian operator in the vertex differential equation of the discrete mesh model to express local features regarding the differential properties of the discrete scalar field on the surface.The reconstructed differential properties preserved the original meaning of the scalar fields,ensuring that the transformation process maintained the local feature details of the initial surface to the maximum extent.In other words,the mapped points of the triangular mesh on the reference domain could be p

关 键 词：局部点云 信息缺失 模型重构 拉普拉斯网格变换 

分 类 号：TP262.4[自动化与计算机技术—检测技术与自动化装置]