条纹投影动态3维测量中相位高精度估计

为了提高条纹投影动态3-D形貌测量精度,采用加窗傅里叶分析辅助相移的方法来减小运动导致的相移误差。首先采用加窗傅里叶分析法估计变形条纹间的实际相移量,然后采用最小二乘法估计出变形条纹的高精度相位分布,最后由估计的相位计算得到场景3维形貌。理论分析了物体运动对相移量的影响,通过仿真研究了所提方法的相移量估计精度,并搭建了实验系统进行验证。结果表明,实验中采用所提方法的相位恢复精度达到0.1673rad,比现有方法有明显提高。该方法用来提高条纹投影动态3-D形貌测量中相位精度是有效的。

High precision phase estimation of projected fringes in dynamic 3-D measurement

In order to improve the accuracy of dynamic 3-D shape measurement by fringe projection, the windowed Fourier analysis was used to reduce the phase shift error caused by motion. Firstly, the actual phase shift between deformed fringes was estimated by windowed Fourier analysis. Then, the phase distribution of the deformed fringes was estimated with high precision by the least square method. Finally, 3-D shape of the scene was obtained from the estimated phase calculation. The influence of object motion on phase shift was analyzed theoretically. The phase shift estimation accuracy of the proposed method was studied by simulation. An experimental system was built to verify the results. The phase recovery accuracy of the proposed method is 0.1673rad. Compared with the existing methods, this method is obviously improved. The results show that the method is effective.