中国机械工程
中國機械工程
중국궤계공정
CHINA MECHANICAl ENGINEERING
2014年
16期
2204-2212
,共9页
航空叶片%点云精简%特征保持%重聚类
航空葉片%點雲精簡%特徵保持%重聚類
항공협편%점운정간%특정보지%중취류
aviation blade%point cloud simplification%feature-preserving%re-clustering
针对现有点云精简方法在航空薄壁叶片叶缘高曲率特征区域及点云稀疏区域存在取样不足的问题,提出了一种基于重聚类策略的精简方法。通过移动最小二乘法定义点---曲面距离函数,区分高低曲率特征,建立了原始点云和精简点云之间的距离关系,在高曲率区域重聚类,实现叶缘高曲率特征保持;并在重聚类时判断点云疏密程度,对稀疏区域进行重聚类。航空叶片、铸造模具等典型复杂曲面测量点云的精简过程中,该方法相比于均匀采样法、层次聚类法,在高曲率区域可保持较高的几何精度。
針對現有點雲精簡方法在航空薄壁葉片葉緣高麯率特徵區域及點雲稀疏區域存在取樣不足的問題,提齣瞭一種基于重聚類策略的精簡方法。通過移動最小二乘法定義點---麯麵距離函數,區分高低麯率特徵,建立瞭原始點雲和精簡點雲之間的距離關繫,在高麯率區域重聚類,實現葉緣高麯率特徵保持;併在重聚類時判斷點雲疏密程度,對稀疏區域進行重聚類。航空葉片、鑄造模具等典型複雜麯麵測量點雲的精簡過程中,該方法相比于均勻採樣法、層次聚類法,在高麯率區域可保持較高的幾何精度。
침대현유점운정간방법재항공박벽협편협연고곡솔특정구역급점운희소구역존재취양불족적문제,제출료일충기우중취류책략적정간방법。통과이동최소이승법정의점---곡면거리함수,구분고저곡솔특정,건립료원시점운화정간점운지간적거리관계,재고곡솔구역중취류,실현협연고곡솔특정보지;병재중취류시판단점운소밀정도,대희소구역진행중취류。항공협편、주조모구등전형복잡곡면측량점운적정간과정중,해방법상비우균균채양법、층차취류법,재고곡솔구역가보지교고적궤하정도。
A novel point cloud simplification method was proposed to avoid insufficient sampling in aviation thin-walled blades’edge regions with high curvature feature and sparse regions with fewer points based on re-clustering strategy.To establish the geometric deviation between the original and simplified point cloud,point-surface distance function was defined to distinguish curvature information based on moving least-square method.The distance function was used to re-cluster the regions with high curvature feature to realize adaptive feature-preserving process.Moreover,the regions with sparse points was distinguished and subdivided to ensure sufficient points in sparse regions.Comparing with uniform sampling method and hierarchical clustering method,the method presented above has higher geometric precision for point-sampled blade surfaces or other complex surface point cloud,such as fan disk.