Integrated time-space modelling based on correlated measurements for the determination of survey configurations and the description of deformation processes

该项目致力于以高空间分辨率分析变形过程。两个主要目标是发展一个空间连续的一致性变形模型，以代表这些过程和实施该模型的非线性敏感性分析。调查继续IMKAD I的研究课题，但也涉及新的课题。两个点云，代表同一物体在两个离散时间点的几何形状，不同的是纯刚体运动或由局部应变叠加的刚体运动，形成了项目的基础。变形模型的建立是双重的，因为它需要一个功能以及随机部分。后者的开发包括确定脉冲扫描器的合成协方差矩阵，并继续进行IMKAD I关于相位扫描器的相应研究，同时考虑到新的和更现实的研究结果。将使用一个显示激光跟踪几何形状的现有完整参考实验室来验证结果;除其他外，将有可能首次验证方差水平以及矩阵的相关结构。关于变形模型的功能部分的方法改进涉及估计的B样条曲面的资格，其表面参数的基础上进行划时代的比较。表面参数和控制点的联合估计是必要的，并且产生于IMKAD I中开发的模型选择方法的适应。在此基础上，利用曲面参数网格来确定刚体运动的要素。如果刚体运动被局部应变叠加，则必须通过识别、统计验证和排除变形区域来迭代地分离各个影响。开发的点云建模和变形分析的方法进行评估，在两个方面。一方面，它们通过标称值进行验证;另一方面，使用代表最新技术水平的算法进行评估。因此，在不同尺度下对三个尺寸的物体进行测量：试样，自由形状壳体和水坝。此外，大气的空间和时间的变化，特别是由于现场活动，新的变形模型，包括刚体运动以及三维应变，导致非线性灵敏度分析的修订，特别是相对于方法“观测组”和“分段线性化”。基于这些近似值，通过原型软件提供最佳扫描仪参数。该软件将以启发式和自动化的方式提供扫描仪相对于物体的位置、扫描质量水平和角度采样率。

This project addresses the analysis of deformation processes with high spatial resolution. The two main objectives are the development of a space-continuous congruency deformation model in order to represent these processes and the implementation of a non-linear sensitivity analysis of this model. The investigations continue the research topics of IMKAD I, but address new topics as well. Two point clouds, representing the geometry of the same object at two discrete points of time and differing in a pure rigid body motion or in a rigid body movement superimposed by local strain, form the project’s basis. The establishment of the deformation model is twofold as it requires a functional as well as a stochastic part. The development of the latter includes the determination of the synthetic covariance matrix of impulse scanners and the continuation of the respective investigations of IMKAD I concerning phase-based scanners, taking new and more realistic findings into account. An available complete reference laboratory showing laser-tracked geometries will be used to verify the results; among other things, a first-time verification of the variance level as well as of the matrix’s correlation structure will be possible. The methodological improvements regarding the deformation model’s functional part concern the qualification of estimated B-spline surfaces for an epochal comparison based on their surface parameters. A joint estimation of surface parameters and control points is necessary and yields to an adaption of the model selection method developed in IMKAD I. Based on these improvements, the grid of surface parameters is used to determine the elements of the rigid body movement. If the rigid body movement is superimposed by local strain, the respective influences have to be separated iteratively by identifying, statistically validating and excluding the distorted areas. The developed methods for point cloud modelling and for deformation analysis are assessed in two ways. On the one hand, they are validated by means of nominal values; on the other hand an evaluation is performed using algorithms which represent the state of the art. Therefore, measurements are performed at three objects with sizes at different scales: a test specimen, a freeform shell and a dam. Furthermore, atmospheric’s spatial and temporal variations can be particularly examined due to the field campaigns.The new deformation model, including rigid body movements as well as three-dimensional strain, leads to a revision of the non-linear sensitivity analysis, especially with respect to the approaches “observation groups” and “piecewise linearization”. Based on these approximations optimal scanner parameters are delivered by a prototype-software. The software will deliver the position of the scanner relative to the object, the scan quality level and the angular sampling rate in a heuristic and automated way.