Three-dimensional shape measurement for an underwater object based on two-dimensional grating pattern projection

Abstract In this paper, a practical method using phase tracking and ray tracing algorithms is proposed for measuring the three-dimensional (3D) shape of an underwater object. A 2D projected sinusoidal fringe goes through the water and illuminates the tested object. Firstly, the phase tracking algorithm is employed to identify homologous points in phase distributions of the deformed fringe captured by the camera and these of the fringe pattern projected by the projector. The projector is regarded as a special camera as regards the stereovision principle. In the calibrated system, both ray directions of the homologous points can be easily figured out. Secondly, the ray tracing algorithm is used to trace the propagation path of each ray and to calculate the 3D coordinates of each point on the tested object's surface. Finally, the whole shape of the tested object can be reconstructed.

[1]  Hossein Golnabi Image evaluation for the synchronised laser scanning systems , 1999 .

[2]  Yoshimasa Kawata,et al.  3-D measurement of objects in a cylindrical glass water tank with a laser range finder , 2003, Proceedings 2003 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS 2003) (Cat. No.03CH37453).

[3]  A Asundi,et al.  Fast phase-unwrapping algorithm based on a gray-scale mask and flood fill. , 1998, Applied optics.

[4]  Yoshimasa Kawata,et al.  Three dimensional measurement of object's surface in water using the light stripe projection method , 2004, IEEE International Conference on Robotics and Automation, 2004. Proceedings. ICRA '04. 2004.

[5]  Su Xian-yu,et al.  New camera calibration technique based on phase measurement , 2007 .

[6]  Peisen S. Huang,et al.  Novel method for structured light system calibration , 2006 .

[7]  Hossein Golnabi Design and operation of a laser scanning system , 2000 .

[8]  Zhengyou Zhang,et al.  A Flexible New Technique for Camera Calibration , 2000, IEEE Trans. Pattern Anal. Mach. Intell..

[9]  Min Zhu,et al.  Stereo Vision Rectification Based on Epipolar Lines Match and Three Variables Projective Matrix , 2007, 2007 IEEE International Conference on Integration Technology.

[10]  Janne Heikkilä,et al.  A four-step camera calibration procedure with implicit image correction , 1997, Proceedings of IEEE Computer Society Conference on Computer Vision and Pattern Recognition.

[11]  V. Srinivasan,et al.  Automated phase-measuring profilometry of 3-D diffuse objects. , 1984, Applied optics.

[12]  Dana H. Ballard,et al.  Computer Vision , 1982 .

[13]  Mumin Song,et al.  Overview of three-dimensional shape measurement using optical methods , 2000 .