Abstract | A technique to calibrate cameras in a two-camera optical tracking system is presented. This technique, which uses a wand to calibrate the two cameras simultaneously, is compared to a traditional approach that calibrates each camera individually. The wand calibration procedure is easier to implement and reduces setup time for extended volume measurements while producing similar results. External and internal parameters required to compute the locations of markers in three-dimensional space, using the image coordinates from both cameras, are determined during the camera calibration. For the calibration technique, a rod with a marker fastened to each end is moved through the viewing volume of both cameras. The wand calibration algorithm determines the parameters by minimizing the difference between the actual and calculated length of the wand over all image frames. Test results are given comparing the two techniques. |
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