Real-time 3D shape inspection system for manufacturing parts based on three-step stripe pattern

Abstract

The objective of this paper is to propose robust, three-step, and spatiotemporal structured light patterns for rapid 3D shape inspection system. To reduce the negative influence of inspected part texture and ambient light, the patterns are constructed by stripe boundary using monochromatic light. The stripe sequence is generated by the Euler Circuit of graph theory under the proposed constraints in space and over time. The location of the boundary stripe is detected by the opposite intensity of the two adjacent stripes instead of the gradient operator so the accuracy is improved. The codeword for each stripe boundary is unique in the projector image plane, depending on the consecutive stripe codes over time. To speed up the corresponding pixel searching between the projector and the camera, the corresponding pixel is formed by the intersection of the epipolar line and the stripe boundary. Last, experiments are conducted to evaluate the robustness and accuracy of the inspection system using the proposed patterns. The results demonstrate that the system has high accuracy performance and high density. © 2010 IEEE.