Marker-based quadri-ocular tracking system for surgery

This study presents a quadri-ocular tracking system, which is based on PC and infrared reflective markers, for a spine surgical robot. The authors mainly focus on four tasks of the system. First of all, a two-step strategy for point correspondence of the multi-ocular system is introduced. The strategy enhances the traditional epipolar constrain for a bi-ocular system, and it decomposes the point correspondence of the multi-ocular system into several bi-ocular systems and corresponding steps to improve the speed of the system. Second, this paper proposes a fast algorithm of three-dimensional point reconstruction based on the perpendicular feet of back-projection lines. A marker constraint is also dug up to solve the combination problem of target recognition. Finally, this study uses a generalised inverse and singular value decomposition-based method to locate the pose of the target. The experiments show that the speed and accuracy of the system are satisfactory.