低成本微型结构光动态三维重建系统研究

Low-Cost and Miniature Structured Light System for 3D Dynamic Reconstruction

基于激光散斑投射的结构光技术只需单张图像即可实现三维重建,是重要的动态测量手段之一。然而,散斑结构光技术在实际中的测量精度较低,无法满足精确测量需求。该研究开发了一套低成本微型结构光系统,提出一种高精度的双目摄像机标定优化方法以及基于两步旋转的立体图像校正方法,提高了系统参数的标定和测量精度。其中,测量系统由一个微型的光学发射器和两个摄像头组成。通过将带有伪随机斑点的单张图案投影到目标对象的表面上,并通过双目相机成像,最终利用特征匹配和三角原理恢复目标的深度和轮廓信息。经测试,所提出的微型结构光系统在使用优化的标定和校正参数的条件下,对圆球、圆柱等标准体的测量精度相比传统标定方法显著提升。其中,球体重建误差为1.05 mm,精度提升52.38%;圆柱重建误差为1.61 mm,精度提高了63.98%。

The laser speckles based structured light technique performs 3D reconstruction with a single shot,which makes it one of the most important ways to achieve dynamic measurement.However,it is inaccurate,which makes it difficult to meet the needs of accurate measurement.This paper develops a low-cost and miniature 3D vision system for dynamic depth recovery.A high-precision calibration optimization method for binocular camera and an optimal stereo image correction method based on a two-step rotation are proposed,which improves the calibration and measurement accuracy of system’s parameters.Our system consists of a miniature projector and two cameras.A single pattern with pseudo-random speckles is projected onto the surface of the target object and imaged by a stereo camera.Another single pattern with pseudo-random spots is projected onto the surface of the target object.The depth and contour information of the target is recovered by using the feature matching and triangulation principle.After testing,the measurement accuracy of the proposed structured light system is significantly higher than that of the traditional calibration method under the condition of using optimized calibration and rectification parameters.Compared with traditional method,the sphere reconstruction error of the proposed system is 1.05 mm,and the accuracy has been increased by 52.38%.The cylinder reconstruction error is 1.61 mm,and the accuracy has been increased by 63.98%.