Research on camera calibration technology of two-dimensional displacement measurement system based on single-chip microcomputer

When it comes to displacement measurement applications that use machine vision, the accuracy of the image has a direct and significant impact on the results of the measurement analysis. Cameras are manufactured with fixed physical and optical parameters. However, due to the inherent error of the lens and the assembly process of the vision system, it is usually necessary to calibrate the camera to obtain accurate camera parameters. This process is unavoidable before using the camera for displacement measurement application. Here, we proposed a two-dimensional displacement measurement system using a single-chip microcomputer, which has the characteristics of a fixed position. In order to overcome the deficiencies of the vision system and the limitations of the calibration environment, the Tsai two-step method and Zhang Zhengyou calibration method were utilized to calibrate the camera used in the system. The project analyzed the distortion coefficient and internal and external parameters obtained from the camera calibration process, and used this information to correct the distortion of the captured images. The experiments demonstrated that the Zhang Zhengyou calibration method provided better robustness and accuracy for the system, which ultimately helped to improve the accuracy of the two-dimensional displacement measurement.