针对传统的条纹投影测量中绝对相位求解方法存在投影图像数量较多以及算法复杂程度高的问题,提出了一种基于Hilbert变换的条纹-灰度线性投影策略及相位求解方法,该方法仅使用3幅投影图像——1幅高频条纹图和2幅灰度线性变化图,通过Hilbert变换求得包裹相位,采用灰度线性变化图像得到基础相位,联立包裹相位和基础相位可得到条纹级数,进而得到绝对相位.通过构建的主动双目系统得到的三维重构结果发现,该方法可以有效恢复被测物体的三维形状,测量精度可达0.1 mm.
Three-Dimensional Measurement of Fringe-Gray Linear Projection Based on Hilbert Transform
To address the problems of large number of projected images and high complex-ity in the traditional fringe projection measurement,this paper proposes a fringe-gray linear projection strategy and phase solution method based on Hilbert transform.The proposed method simplifies the measurement process by using only three projection images:one high-frequency fringe image and two grayscale linear change maps.The wrapping phase is obtained by the Hilbert transform,and the basic phase is obtained by using the grayscale linear change image.By combining the wrapping phase and the basic phase,the absolute phase,which represents the fringe progression,can be obtained.The 3D reconstruction re-sults obtained by the constructed active binocular system shows that the proposed method can effectively restore the 3D shape of the measured object,with a measurement accuracy of 0.1 mm.
3D measurementfringe-gray linear projectionHilbert transformabsolute phaseactive binocular
万方数据
维普
