Alignment error compensation for defect measuring system of small bores

WEI Dongliang; WU Bin

doi:10.7510/jgjs.issn.1001-3806.2016.05.007

In order to satisfy the requirement of miniaturization in measuring defects inside small bores, a new approach was proposed with external light importing and internal images exporting. This method solved the problem of the limited dimensional accessibility of small bores. Compared with the traditional measuring methods, the new method made the breakthrough and the method was without built-in sensors. The key problem of alignment error that had a great influence on measurement results was studied deeply and the measuring system was improved. The reasonable alignment error compensation method based on image correction was presented and a measuring system was built. Several tests were conducted on sample pipe with diameter of 12mm. The simulated point defects with diameter of 0.6mm, 0.8mm, 1.0mm were set on the internal surface of sample pipe. The results showed that after image correction on the unfolding image, the mean deviation of the defect diameter was less than 0.02mm, and the standard deviation was less than 0.03mm. The alignment error compensation method is reliable and able to improve the precision of measurement.

Alignment error compensation for defect measuring system of small bores

Corresponding author: WU Bin, wubin@tju.edu.cn

1. State Key Laboratory of Precision Measurement Technology and Instrument, Tianjin University, Tianjin 300072, China

Received Date: 2015-07-06

Accepted Date: 2015-07-17

Available Online: 2016-09-25

Abstract: In order to satisfy the requirement of miniaturization in measuring defects inside small bores, a new approach was proposed with external light importing and internal images exporting. This method solved the problem of the limited dimensional accessibility of small bores. Compared with the traditional measuring methods, the new method made the breakthrough and the method was without built-in sensors. The key problem of alignment error that had a great influence on measurement results was studied deeply and the measuring system was improved. The reasonable alignment error compensation method based on image correction was presented and a measuring system was built. Several tests were conducted on sample pipe with diameter of 12mm. The simulated point defects with diameter of 0.6mm, 0.8mm, 1.0mm were set on the internal surface of sample pipe. The results showed that after image correction on the unfolding image, the mean deviation of the defect diameter was less than 0.02mm, and the standard deviation was less than 0.03mm. The alignment error compensation method is reliable and able to improve the precision of measurement.

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Reference (16)

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Alignment error compensation for defect measuring system of small bores

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