5.8. Summary

• Calibration is a process that finds unknown parameters relating different coordinates systems.

• In a CAI system there are several calibration processes that may need to be performed.

• The most common calibration processes in CAI are: pivot point calibration, template-based calibration, hand-eye calibration and camera parameters calibration.

• Pivot point calibration finds the transformation between a tracked sensor/marker to the tip of a tool by pivoting the tool on a point.

• Template-based calibration uses a tracked template with a know geometry and the instrument is placed “inside” in order to find the geometric relationship.

• Camera parameters calibration finds the transformation between a 3D point and a 2D point, also by taking several images.

• Hand-eye calibration finds the transformation between a tracked sensor/marker and a camera by taking several images of the same point.