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A Novel Vision-Based Pose Measurement Method Considering the Refraction of Light
1Key Laboratory for Precision and Non-Traditional Machining Technology of the Ministry of Education, Dalian University of Technology, Dalian 116024, China. lw2007@dlut.edu.cn.
Sensors (Basel, Switzerland)
|December 15, 2018
Summary
This study introduces a new imaging model to improve vision-based pose measurement accuracy in wind tunnels. The method corrects for refraction errors caused by observation windows, significantly enhancing measurement precision for aircraft testing.
Area of Science:
- Aerospace Engineering
- Optical Metrology
Background:
- Vision-based pose measurement is crucial for aircraft performance testing in wind tunnels.
- Glass observation windows cause significant measurement errors due to light refraction.
Purpose of the Study:
- To develop an advanced imaging model for accurate vision-based pose measurement.
- To mitigate measurement errors caused by wind tunnel observation windows.
Main Methods:
- Established a nonlinear camera calibration model accounting for window refraction.
- Developed a linear calibration method for the observation window's normal vector.
- Utilized a coplanarity constraint-based matching method to calculate pose parameters.
Main Results:
- Experimental validation demonstrated the method's effectiveness.
- Achieved approximately 57% increase in displacement accuracy.
- Achieved approximately 33.6% increase in angle measurement accuracy.
Conclusions:
- The proposed imaging model significantly improves vision-based pose measurement accuracy.
- The method effectively addresses refraction errors in wind tunnel applications.
- The technique offers a viable solution for high-accuracy aircraft performance testing.
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