The basic concept of AR navigation

Figure 1. The basic concept of AR navigation

High Precision Camera-tracker Calibration with an Optical Tracking System

 
  • Augmented reality (AR) navigation requires a transformation matrix from tracker to camera obtained from camera-tracker calibration.
 
  • Camera-tracker calibration is one of the important elements to determine the accuracy of augmented reality based surgical navigation system (see TCCM in figure 1).
 
  • The optical tracking system itself has the spatial error which increases with the distance.
 
  • Therefore, the small range of motion during camera-tracker calibration is required to reduce the spatial error.
 
  • Moving a calibration pattern (the proposed method) instead of a camera (the conventional method) is considered as a solution to reduce the spatial error (see figure 2)
Method comparison
Figure 2. Comparison between the conventional method (right) and the proposed method (left)
  
 
Reference
– S. Lee, H. Lee, H. Choi, J. Hong, A Simple and Accurate Camera-Sensor Calibration for Surgical Endoscopes and Microscopes, The 2014 Workshop on Augmented Environments for Computer Assisted Interventions (AECAI 2014), pp.98-107, 2014.