A METHOD AND SYSTEM FOR FINDING A TOOL CENTER POINT FOR A ROBOT USING AN EXTERNAL CAMERA

摘要

Method and system for finding a relationship between a tool-frame attached at a robot wrist and kinematics using an external camera. Position and orientation of the robotic wrist define a known wrist-frame, leaving initially unknown the relationship of the tool-frame with the Tool Center Point (TCP). The camera captures an image of the tool and an appropriate point is designated as the TCP. The robot is moved placing the wrist into poses, each pose constrained such that the TCP point falls within a specified geometric constraint. A TCP relative to the wrist frame is calculated as a function of the geometric constraint, and its position and orientation for each pose. The tool- frame relative to the wrist frame may be the calculated TCP. Refining calibration of the tool-frame may account for tool orientation and operational direction. The camera may calibrate using a simplified extrinsic technique.