Robust stereo calibration system and method for accurate digital image correlation measurements
US8248476B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 3, 2009 |
| Grant date | Aug 21, 2012 |
| Priority date | — |
| Expiry date | Feb 1, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N13/296
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A stereo calibration method is proposed to calibrate an interface's shape and position when the measurement system is in one media and measures deformation and strain of an object that is submerged in a different media. After the interface's shape and position are modeled by parameters, an explicit model of object points as measurement is established taking account of refraction happening at the interface. Efficiency and convergence are assured by using measurement of object points to acquire initial estimates for refraction angles at the interface. Then, an optimization method is performed to get the optimized value of interface parameters. Last, based on the resulting interface parameters, 3-dimensional positions of object points in all the subsequent measurement could be reconstructed accurately. Therefore, the distortion induced by refraction in the measurement is corrected. Numerical simulations of the proposed calibration process confirm that it is both robust and accurate for a range of experimental conditions, even in the presence of Gaussian noise in the measurement.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.