Optimization of Terrestrial Laserscanning Networks

OPTIMIZATION OF TERRESTRIAL LASERSCANNING (TLS) NETWORKS BASED ON SENSITIVITY ANALYSIS (OPTITLS)

Sensitivity analysis as understood in engineering geodesy usually deals with the ability to detect small deformations based on an assumed or expected deformation model. In this project, deformations will be monitored by Terrestrial Laser Scanning (TLS) from different scanning sites (viewpoints). The challenge is to develop a multi-criteria optimization method for a first and second order geodetic design of a TLS network. This covers the number and positions of the viewpoints as well as the scanning settings (e.g. scan rotation velocity, angular resolution). The optimization should cover completeness and sensitivity. All this information can be provided in the planning phase for the viewpoint network.

Assuring completeness means that all surfaces, edges and corners of the object are visible in the registered joint point cloud and sufficient overlap among the individual scans for registration is guaranteed. The completeness optimization using e.g. Greedy algorithms  deliver a minimum number of TLS viewpoints together with their positions.

The objective function for the final optimization is the determinant of the covariance matrix in the direction of the deformation model. Scanning parameters like scan rotation rate and angular resolution, object-scanner distance and incidence angle, influence the sensitivity with respect to deformation models. A metaheuristic approach will be used for the sensitivity optimization.

PRINCIPAL INVESTIGATOR

Prof. Dr.-Ing. habil. Dr. h.c. Volker Schwieger
Institute of Engineering Geodesy (IIGS), University of Stuttgart

RESEARCHER

M.Sc. Pauline Speidel (IIGS)

FUNDING

German Research Foundation, DFG Sachbeihilfe