"高反光元件三维面形测量技术优化与应用研究"

Abstract: In advanced manufacturing, on-line quality inspection of processed components is required. The fringe projection three-dimensional measurement technology is adopted because it meets the requirements of online and non-contact. However, the significant differences in the reflection rate of metal material surfaces can lead to overexposure and underexposure of captured structured light images, resulting in missing or incorrect final measurement data. In response to this issue, incomplete point cloud data directly obtained from measurements and component design data obtained from Computer-Aided Design (CAD) are used for iterative closest point (ICP) point cloud registration to obtain point cloud data estimating the surface shape of the object being measured in the camera coordinate system. This data is used as an estimation of the surface shape, combined with system calibration parameters, to establish a correspondence relationship between the image intensity of same-named points between projection and imaging. The camera's imaging response curve of the light intensity for each point on the element to be measured is used to calculate the projection grayscale range and minimum projection grayscale. Finally, the non-equal coefficient projection grating generated is used for three-dimensional topography measurement of high-reflective elements. Experimental results show that the proposed method can more completely achieve three-dimensional surface shape measurement of high-reflective elements without changing the structural parameters of the measurement system or increasing the complexity of the measurement system.