基于SURF算法的在线三维测量方法

On-line Three-Dimension Measurement Method Based on SURF Algorithm

提出了一种采用加速鲁棒特征算法匹配运动物体的特征点,实现在线三维测量的方法.该方法只需投影一固定的正弦光栅到在线运动中的被测物体表面上,使投影光栅线垂直运动方向,当物体每移动相同的距离,由CCD采集到相应的变形条纹图,从中提出对应的背景光场,借助SURF算法对各帧背景光场的物体进行特征匹配,即可获得一组具有等步相移量的等效相移条纹图,从而采用等步相移算法可重构出在线运动物体的三维面形.实验验证了该方法的有效性和可行性,并与在线FTP方法进行了比较,所提方法的平均绝对误差小于在线FTP方法的二分之一,均方根误差小于在线FTP方法的四分之一.

An on-line three-dimensional measuring method based on speeded up robust features algorithm is proposed.Only one fixed sinusoidal grating is projected onto the moving measured object to guarantee the fringe direction perpendicular to the moving direction.While the object moves at the same spacing,the corresponding deformed patterns are captured by the CCD camera respectively.Then the background patterns can be extracted from the corresponding captured deformed patterns.With the aid of Speeded Up Robust Features （SURF）feature points matching algorithm on the background patterns,a group of equivalent phase shifting deformed patterns with the same shifting phase can be cut out.So the 3D surface of the online moving object can be reconstructed.The experimental results show the feasibility and effectiveness of the proposed method.Moreover,compared with the online Fourier Transform Profilometry （FTP）method,its average absolute error is less than one-half of that of the online FTP and its root mean square error is less than one quarter of that of the online FTP.