A calibration method based on defocused image is proposed for stereo vision sensor with large field of view (FOV) to simplify operation process and gain accurate and steady camera calibration. First, a defocusing position is selected between the stereo vision system and the measurement position. The intrinsic parameters of cameras are obtained by using the template images at the defocusing position. Second, the external parameters of the stereo vision are obtained by using the template images at the measurement position. Finally, a laboratory calibration experiment and an experiment of measuring the helicopter blade motion parameters are conducted to verify the proposed method. Experimental results show that the method features in simple operation, high accuracy and reliability. In a field of 4.6 mm×2.3 mm, the mean error and the RMS error of a 505.00 mm distance between two feature points on the target are 0.647 mm and 0.780 mm respectively. Therefore this method can meet the requirements of onsite calibration with high-precision for the measurement of helicopter blade motion parameters.
YU Shuzhen, OU Qiaofeng, XIONG Bangshu, CHEN Yaofeng
. A Calibration Method Based on Defocused Image for Stereo Vision Sensor with Large FOV[J]. Journal of Applied Sciences, 2019
, 37(6)
: 795
-805
.
DOI: 10.3969/j.issn.0255-8297.2019.06.004
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