Sub-Pixel Extraction of Laser Stripe Center Using an Improved Gray-Gravity Method †Report as inadecuate


Sub-Pixel Extraction of Laser Stripe Center Using an Improved Gray-Gravity Method †


Sub-Pixel Extraction of Laser Stripe Center Using an Improved Gray-Gravity Method † - Download this document for free, or read online. Document in PDF available to download.

School of Mechanical Engineering, Hebei University of Science and Technology, Shijiazhuang 050018, China



This paper is an extended version of our paper published in the 10th International Conference on Sensing Technology ICST, Nanjing, China, 11–13 November 2016.





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Academic Editors: Ruqiang Yan, Subhas Chandra Mukhopadhyay and Gui Yun Tian

Abstract Laser stripe center extraction is a key step for the profile measurement of line structured light sensors LSLS. To accurately obtain the center coordinates at sub-pixel level, an improved gray-gravity method IGGM was proposed. Firstly, the center points of the stripe were computed using the gray-gravity method GGM for all columns of the image. By fitting these points using the moving least squares algorithm, the tangential vector, the normal vector and the radius of curvature can be robustly obtained. One rectangular region could be defined around each of the center points. Its two sides that are parallel to the tangential vector could alter their lengths according to the radius of the curvature. After that, the coordinate for each center point was recalculated within the rectangular region and in the direction of the normal vector. The center uncertainty was also analyzed based on the Monte Carlo method. The obtained experimental results indicate that the IGGM is suitable for both the smooth stripes and the ones with sharp corners. The high accuracy center points can be obtained at a relatively low computation cost. The measured results of the stairs and the screw surface further demonstrate the effectiveness of the method. View Full-Text

Keywords: line structured light sensor; improved gray-gravity method; adaptive sampling regions; uncertainty analysis; sub-pixel center extraction line structured light sensor; improved gray-gravity method; adaptive sampling regions; uncertainty analysis; sub-pixel center extraction





Author: Yuehua Li †, Jingbo Zhou †,* , Fengshan Huang † and Lijian Liu †

Source: http://mdpi.com/



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