Cognex Corporation
SYSTEM AND METHOD FOR AUTOMATIC HAND-EYE CALIBRATION OF VISION SYSTEM FOR ROBOT MOTION

Abstract:

This invention provides a system and method that automatically decides motion parameters of hand-eye calibration, and conducts the calibration procedure with minimal human intervention. It automatically computes hand-eye calibration motion parameters and spatial positions during pre-calibration, whereby the calibration pattern can continuously remain inside, and covering, the entire field of view FOV of the vision system camera, providing a fully automatic hand-eye calibration process. This system and method advantageously operates in a robot-based hand-eye calibration environment and can compensate for a cantilever effect between the calibration target and the FOV. A hand-eye calibration computes the transformation from the robot coordinate space to the camera coordinate space. This generally avoids a need to manually move the robot through a set of spatial positions in which the camera then acquires images and locates calibration features on the object at each position to establish the relationship between the robot and camera.