Online Calibration Technology of the Vision System in Intelligent Coordinate Measuring Machine

An on-line calibration technology of the vision system in intelligent Coordinate Measuring Machine(CMM)is proposed.According to the calibration principles of CCD cameras,the CMM brings the CCD camera to be calibrated to produce the relative translation with respect to the center of the white ceramic standard sphere(the calibration characteristic point)along the x,y,z axis.Thus,the coordinates of the different positions of the calibration characteristic point in the probe coordinate system can be generated adopting the feature of the high translation accuracy of CMM.By introducing the probe coordinate system,the calibration mathematic model is established,the calibration steps are given and the calibration system is set up.The comparing calibration precision between the vision parameters in the calibration system of the intelligent CMM and the special calibration system is within ±1μm,which meets the requirements of the practical accuracy completely.