A constraint-based parameterization technique for B-spline surfaces
A constraint-based parameterization technique for B-spline surfaces
复制标题
基于约束的 B 样条曲面参数化技术
DOI：
10.1515/jag-2015-0003
复制
发表时间：
2015
影响因子：
1.4
通讯作者：
H. Neuner
中科院分区：
文献类型：
--
作者：
C. Harmening;H. Neuner
摘要 变形分析是工程大地测量学的经典任务之一。激光扫描仪的发展改变了数据采集以及分析策略；区域方法不再是基于点的方法，而是成为焦点。在本文中，提出了一个项目，旨在开发时空连续搭配以描述区域变形。除其他外，这种搭配还需要对确定性趋势进行建模，这在本研究中是通过估计 B 样条曲面来实现的。估计此类自由曲面的主要挑战之一是定义适当的参数形式，这是本贡献的重点。通过将获取的点云投影到称为 Coons patch 的基面上来获得初始参数化。通过重新参数化，这些初始参数被迭代地改进。为了处理不规则的点密度，开发、比较和评估了几种在平差中引入边界约束的策略。
Abstract Deformation analysis is one of the classical tasks in engineering geodesy. The development of the laser scanner has changed the data acquisition as well as the analysis strategy; instead of point-based approaches, areal ones move into focus. In this paper, a project is presented which aims to develop a spatiotemporal continuous collocation in order to describe areal deformations. The collocation requires among other things the modelling of a deterministic trend which is realized by the estimation of B-spline surfaces in the present study. One of the main challenges in the estimation of such freeform surfaces is the definition of an appropriate parameter form which is in the focus of this contribution. An initial parameterization is obtained by projecting the acquired point cloud onto a base surface called Coons patch. By means of a reparameterization, these initial parameters are improved iteratively. In order to handle irregular point densities, several strategies to introduce boundary constraints into the adjustment are developed, compared and evaluated.