Large Scale Workpieces Measurement Based On Binocular Line-structured Light

The 3D coordinate measurement on large scale workpieces has an important significance to the entire workpieces' production and assembling quality. Obtaining of the related sizes of workpieces can feed back to production manufacture process promptly. In the practical production, the problems such as low accuracy and efficiency in this kind of measurement have not been well dealt with, it greatly restricted the product efficiency and production quality.According to the development and practice of Modern Shipbuilding Huge Size 3-D Numeral Measurement System, we did a deep research and many related experiments on Line-structured light of this project, including system modeling, camera and structure parameters calibration and selection of scanning mode. These works provide a foundation to practical application of large scale workpieces measurement in industrial scene.Many different kinds of system models emerged on the base of the principle of line-structured light. Not only the system model on the principle of triangulation was built, but also a binocular line-structured light sensor was put forward in this paper in view of the "blinding area" problem in general line-structured light scanning. The system model was established, also calibrated due to the requirement. The accuracy of calibration was proved by experiments. The method using the binocular calibration assists system parameter calibration to improve the precision was proposed, and also the calibration method of the rotational axis position of this sensor was mentioned.According to the characters of large scale workpieces, hardware structure was designed to assist the scan process. A scanning method based on mobile coordination measuring system was used to scan the feature parts, not the complete appearance of the workpieces. Positional information was used to trigger the camera grabbing images. It finally realized a high precision and efficiency.