Concepts and results in the development of a hybrid tracking system for CAS

Abstract

We present the design and the results achieved in the development of a hybrid magneto-optic tracking system suitable for computer aided surgery. Our approach towards a reliable and accurate hybrid position sensor system that is not entirely dependent on an unobstructed line-of-sight between sensor assembly and patient is the combined use of an optical tracker with a direct current (DC) pulsed electromagnetic tracking system (EMTS). The proposed hybridization method aims at providing both accurate and uninterrupted position data by overcoming the drawbacks of both tracking technologies. Results presented include the preliminary assessment of algorithms for fusion of position data from both sensor systems, for calibrating the EMTS to the environment and for detecting systematic distortions in the DC tracking system caused by ferromagnetic materials in order to improve the reliability of the proposed system.