Accuracy enhancements of industrial robots through close-range photogrammetry

点击翻译按钮获取中文摘要

Industrial robots are highly repeatable. Once the pose of a robot's end-effector has been manually taught, the robot end-effector can move to that pose over and over again with a position error that is typically smaller than 0.050 mm. However, the accuracy of industrial robots is relatively poor. If the robot's end-effector is required to move to a pre-calculated pose (as in offline programming), its position error may reach a couple of millimetres. Fortunately, a technique known as robot calibration allows improving the accuracy of industrial robots. Calibrated industrial robots are already being used in many aerospace applications such as deburring, polishing, drilling, and fastening. However, there is still a need for reducing the cost of robot calibration and for further improving the accuracy of robots, which can be done through developing more effective calibration techniques and using affordable but well-adapted metrology equipment. This project aims to improve the accuracy of industrial robots with the help of two Canadian-made 6D measurement devices. Namely, two commercial photogrammetry based systems manufactured by Creaform will be used in this project: the C-Track and the MaxSHOT 3D. Firstly, a special multifaceted artefact will be designed and fabricated, the pose of which can be measured with any of these two Creaform's 6D devices. Then, novel robot calibration techniques will be developed for the specific use with these two 6D devices. In parallel, an automated procedure will be developed for the dynamic robot pose correction of certain industrial robots with the help of a C-Track. Finally, a dedicated procedure will be developed for the geometry inspection of parts using a robot guided by a C-Track.