Eccentricity Measurement of Auto-Hub's Pitch Circle

Abstract:

In order to measure the eccentricity of auto-hubs center hole and bolt holes, a machine vision system is proposed in this article. Instead of normally used telecentric lens, a perspective lens is used in the vision system because of the large field of view. The eccentricity is calculated by sub-pixel edge extracting and circle-fitting algorithm. A correction method is put forward to compensate the systematic error resulting from the different perspective distortions of the center hole and the bolt holes because of the height difference between the center hole and the bolt holes, as well as the offset between the hubs center shaft and the optical axis of the imaging system. The maximum variation and the standard variation are calculated to analyze the measurement uncertainty. Experiments had shown that the maximum variation and the standard deviation of the corrected measured eccentricity were reduced to 1/6 and 1/8 of those without correction.

• Periodical: Applied Mechanics and Materials (Volume 431)
• Pages: 121-125
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.431.121
• Online since: October 2013
• Authors: Shu Xia Guo, Bin Feng, Liang Zhang, Wei Zhang, Lei Wang*
• Keywords: Auto-Hub, Eccentricity, Pitch Circle, Vision Measurement

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