| 摘要 |
<p>A method and apparatus for measuring strain distribution on a deformed surface utilizes a video (56) or photographic camera for taking two images (30) of the surface which are taken at an angle (41) to each other. The surface carries a deformed grid (10) which has grid points (24) that are digitized using images from the camera. The digitized points each form one set of two-dimensional coordinates. Each point of the one set of coordinates is correlated with a corresponding point of the other set. The two sets of two-dimensional coordinates are then used in conjunction with the geometrical relationship between the images to calculate a single set of three-dimensional coordinates for the grid points (24). The three-dimensional coordinates (42) are then used in groups of three adjacent points to calculate strain (20) over the surface.</p> |
