Method for spatial measurement of holes
US4647208A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 22, 1985 |
| Grant date | Mar 3, 1987 |
| Priority date | — |
| Expiry date | Jul 22, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B11/00
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The three-dimensional position of a hole through a workpiece is determined using back lighting or front lighting (feature lighting) to determine the centroid of the hole's image in two-dimensional computer memory image space. The centroid determines a line of sight between the center of the hole's image and the actual center of the hole in real space. Next a crosshair lighting pattern (structured lighting) is projected onto the plane of the workpiece in the neighborhood of the hole. From the reflected crosshair pattern an equation representing the plane containing the hole is determined in image space. The intersection of the plane equation and the line of sight is computed and the three-dimensional, real space position of the hole is determined for comparision with an ideal position established during calibration.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.