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Estimation of planar angles from non-orthogonal imaging
Akash Kumar1, C Chandraprakash1
1Department of Mechanical Engineering, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh 208016, India.
The Review of Scientific Instruments
|January 8, 2024
Summary
This study presents a fast, inexpensive method for estimating planar angles using smartphone images. The technique utilizes sparse reconstruction and two-view geometry for accurate on-site measurements.
Area of Science:
- Computer Vision
- Geometric Measurement
Background:
- Traditional photogrammetry relies on expensive equipment and complex algorithms for 3D scene reconstruction.
- Accurate geometrical parameter estimation is crucial for various engineering and measurement applications.
Purpose of the Study:
- To develop a computationally inexpensive method for estimating planar angles using smartphone imagery.
- To enable on-site geometrical measurements with readily available technology.
Main Methods:
- Utilized two-view geometry and linear algorithms for sparse reconstruction.
- Employed scale-invariant feature transform (SIFT) for point correspondence.
- Applied epipolar constraints and the eight-point algorithm to estimate the essential matrix.
- Determined camera projection matrices and used linear triangulation for 3D point cloud generation.
Main Results:
- Successfully estimated planar angles from non-orthogonal smartphone images.
- Achieved an average error of 3% on non-curved edges.
- Completed estimations in under 10 seconds using only ten images.
Conclusions:
- The developed method offers a simple and efficient approach for geometrical measurements.
- Its integration into smartphones allows for accessible on-site measurements and deformation analysis.
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