Large-scale full-field metrology using projected fringes: some challenges and solutions

Jonathan M. Huntley; Tokunbo Ogundana; Richard L. Burguete; C. Russell Coggrave

doi:10.1117/12.726222

18 June 2007 Large-scale full-field metrology using projected fringes: some challenges and solutions

Jonathan M. Huntley, Tokunbo Ogundana, Richard L. Burguete, C. Russell Coggrave

Proceedings Volume 6616, Optical Measurement Systems for Industrial Inspection V; 66162C (2007) https://doi.org/10.1117/12.726222
Event: Optical Metrology, 2007, Munich, Germany

Abstract

The application of optical techniques to the measurement of shape and deformation of structures in the aerospace industry poses unique challenges resulting from the large length scales involved, which are typically in the 1-10 m range. For example, the relative immobility of large samples requires a network of sensors to be linked into a common global coordinate system; traceable calibration requires the development of new types of calibration artefact; and traditional interferometric techniques for displacement field mapping are frequently too sensitive to observe the physical effect of interest. We describe a system designed to address some of these problems based on the projected fringe technique combined with temporal phase unwrapping. Multiple cameras and projectors are linked into a common coordinate system using calibration concepts borrowed from the photogrammetry field. Traceable calibration is achieved through the use of reference spheres separated by a bar of known length. Traditional two-dimensional image processing techniques for recognizing circles (Hough transforms) have been extended to the automatic detection of spheres within the measured 3-D point clouds. Bundle adjustment software has been developed to refine the camera and projector calibration parameters as well as the rigid body translation and rotation coordinates defining the poses of the calibration artefact. An overview of all these aspects of the developed techniques is given in the paper. Typical results from a compression test on a large scale aluminium structure, performed on-site at Airbus UK using the developed system, are also presented.

Citation Download Citation

Jonathan M. Huntley, Tokunbo Ogundana, Richard L. Burguete, and C. Russell Coggrave "Large-scale full-field metrology using projected fringes: some challenges and solutions", Proc. SPIE 6616, Optical Measurement Systems for Industrial Inspection V, 66162C (18 June 2007); https://doi.org/10.1117/12.726222

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available