Multi-view x-ray imaging of logs
US6757354B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 20, 2002 |
| Grant date | Jun 29, 2004 |
| Priority date | — |
| Expiry date | Oct 20, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S378/901
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus is disclosed for mapping the relevant material properties of a log, such as knot location and extent. The outer shape of the log under bark is also revealed using this method, and the boundary between the heartwood and sapwood is accurately mapped. The apparatus includes three x-ray sources and arrays of x-ray detectors, for measuring the attenuation of the wood in the log. Deviations in attenuation are related to changes in density, which are indicative of knots and other defects. Accurate estimates of shape, density and knot location render improved sawing decisions at the headrig of a sawmill, which improve the yield of high quality lumber from a given log. The techniques may also be used in a system for sorting logs according to quality.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.