This dissertation proposes a novel calibration system capable of automatically calibrating industrial robots. Often, inaccurate assumptions about real links parameters or even small offsets exist in the individual robot joints that lead to errors in the internal kinematic model equation and, as a consequence, affect the accuracy of a robotic system. To solve this problem, the proposed approach introduces a completely new technique for industrial robot calibration. The proposed system consists of an industrial robot manipulator, a camera, a laser fixture attached to the robot tool center point (TCP), a PC-based interface, and a new position sensitive calibration device (PSCD). This wireless calibration device is comprised of two fixed position sensitive detectors (PSDs) tilted with an angle between them to reflect the laser line from one PSD to the other. Such a device is capable of feeding back the movement information needed to localize the TCP frame relative to the device frame. The new calibration approach is not only able to compute the joint offset parameters of the robot but is also capable of simultaneously calibrating the robot's workpiece relationship. It was also designed to be faster, simpler and cheaper than any other methods. Throughout this dissertation, the newly developed calibration device, the principle of our calibration system and the control approach needed to achieve automation of the entire system are presented and discussed. Finally, the feasibility of the overall calibration system including device hardware, software and calibration algorithms was demonstrated with experimental results.
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