Point cloud modelling
Point clouds acquired by means of a terrestrial laser scanner have a lower single point accuracy than tacheometrically determined signalised points. In order to achieve comparable accuracies in the analysis nevertheless, the redundancy of the point clouds is exploited to determine substitute surfaces. B-spline curves and surfaces have proven to be particularly powerful for this purpose, as they enable the modelling of a large number of artificial and natural objects. However, especially when modelling natural surfaces, the classical tensor product representation of B-spline surfaces reaches its limits. For this reason, we develop B-spline based strategies which allow for a satisfying approximation even of complex natural surfaces.
|Fig. 1: Laser scanning point cloud and approximating B-spline surface|