Measurement of cylinder diameter based on computer vision system

The forgings is widely used in mechanical manufacturing industry. The online measurement with high-precision is very important for the quality control. In order to measure the large forgings´ size, a system that using linear structured light source and CCD image sensor is developed. The system puts forward to test the deformation of the light plane when the light meets the surfaces of workpieces. By analyzing the laser curve image, it calculates the spacial conic and the parameters thought coordinates transition. The measuring principle and the building process of the system are described. To detect the structured-lighted-stripe vision sensor model, a new calibration method based on the combined target is proposed. The experiments demonstrate the high repeatability and accuracy of the system. The experimental results have proved that the repeatable accuracy is within 0.04mm and the measured relative error is less than 0.13%.