Präzise Positionierung und Orientierung innerhalb von Gebäuden

Die vorliegende Arbeit entstand im Rahmen einer Forschungskooperation zwischen der Hochtief AG, dem Institut für Baubetrieb der TU Darmstadt und dem Geodätischen Institut der TU Darmstadt. Das Ziel dieser Arbeit war es, ein präzises, für Baustellen geeignetes UWB Positionierungssystem zu entwickeln. Zusätzlich zu der Position sollte auch die Orientierung einer Digitalkamera bestimmt werden, um Bildaufnahmen während der Ausführungs- und Betriebsphase von Bauwerken zu verorten. Als eine optimale Ergänzung und Unterstützung für die Positionierung wird ein auf quasistatischen Magnetfeldern basierende Positionierungsverfahren vorgestellt, dessen besonderer Vorteil darin liegt, dass es zusätzlich zu der Position die Orientierung ohne Einsatz von Antennenarray liefern kann. Ein wichtiger Schwerpunkt dieser Arbeit bestand zudem in der Entwicklung neuer Algorithmen für die direkte Lösung nichtlinearer geodätischer Probleme am Beispiel des räumlichen Bogenschnitts sowohl mit als auch ohne Überbestimmung. Dazu wird mit Hilfe der Spektralen Theorie auch ein neues Verfahren zur Lösung von räumlichen Streckennetzen vorgestellt

The rapid development of information and communication technologies in recent years has opened new fields of application, in which the localization plays a crucial role. The precise determination of the position and the orientation inside buildings is a particular technical challenge, since the classical positioning systems do not meet the specific requirements of precision in indoor environments. Numerous issues are still to be solved, for example: the availability of signals due to shadowing, the reliability of detection due to multipath effects, the accuracy of position and the ability to deliver the 3D or even more the 6D-Position. New technologies applicable for precise indoor localization are ultra wide band (UWB) and pulsed magnetic field. They allow the determination of distances in indoor environments with a very high spatial resolution even through building materials like walls. Thus, exact positioning methods could be applied. To verify the suitability of the UWB technology several stimulations are performed in this dissertation. They are based on a ray-tracing model developed using elementary propagation scenarios, such as direct propagation, reflection and diffraction. The research presented in this dissertation provides a high resolution ultra wideband (UWB) positioning system based on the trilateration principle. Due to the extremely large bandwidth of the UWB signal the developed UWB-ILPS (Indoor Local Positioning System, ILPS) provides a centimeter positioning accuracy in dense multipath indoor environments for the 3D localization. For the position estimation a novel algorithm was developed, which delivers a solution for over determined nonlinear systems of equations without using linearization methods or approximation solutions. In a recursive least squares method additional observations can be added gradually and an adjusted solution can be calculated. Furthermore, to solve n-dimensional dynamic distance networks a new method using the spectral decomposition and the rank properties of the matrix of distance squares, in which the coordinates of the grid points are computed is introduced. Thereby noisy measurements can be corrected and missing ones can be calculated. As an extension to the UWB-ILPS, a positioning system based on artificial magnetic fields is introduced. It is suggested to utilize alternating DC magnetic signals, which show no NLoS (Non Line of Sight) errors or multipath effects. For the computation of the 6D position of the mobile sensor new methods are developed that allow to ameliorate the update rate of the system. Magnetic field measurements are strongly affected by the interferences from the environment and the Earth's magnetic field. To minimize these negative effects, a noise reduction method is implemented by adaptive filtering and reference stations. Keywords: Ultra-wideband (UWB), Positioning, Ranging, Ray Tracing, Delay Estimation, Multipath Channel, Subspace Based Estimation, Adaptive Filtering, Real Time OS, Embedded Systems, Magnetic Field System, Indoor Local Positioning System