Method and system for moisture grading wood products using superimposed near infrared and visual images
Near InfraRed NIR technology, including NIR cameras and detectors, and one or more visual cameras are used to generate superimposed image data representing a visual/NIR composite image of wood product and correlating moisture levels with physical features of the surfaces of the wood product. By analyzing the visual/NIR composite image represented by superimposed image data, moisture pockets near an open physical feature that, absent the presence open physical feature would be a problem, can be identified and ignored. Based on the identified moisture levels at various locations in a given wood product, and the proximity of physical features to the identified moisture locations, one or more actions are taken with respect to wood product to ensure the wood product is put to the most efficient, effective, and valuable use.
1. A method for detecting moisture levels in wood products comprising:
generating a moisture level to greyscale mapping database, the moisture level to greyscale mapping database containing data that maps moisture level to Near InfraRed (NIR) image greyscale values for one or more wood products;
providing an NIR analysis station, the NIR analysis station including one or more sources of illumination positioned to illuminate a surface of a wood product, the NIR analysis station including one or more NIR cameras positioned to capture one or more NIR images of the illuminated surface of the wood product;
positioning a wood product to be analyzed in the NIR analysis station such that a first surface of the wood product to be analyzed is illuminated by the one or more illumination sources;
capturing, using the one or more NIR cameras, one or more NIR images of the illuminated first surface of the wood product;
processing the one or more NIR images of the illuminated first surface of the wood product to generate NIR greyscale images indicating different moisture levels in the illuminated first surface of the wood product;
processing the NIR greyscale images using the moisture level to greyscale mapping database to identify moisture levels for the first surface of the wood product;
providing one or more visual image cameras, the one or more visual image cameras positioned to capture visual images of the first surface of the wood product;
capturing, using the one or more visual image cameras, one or more visual images of the first surface of the wood product;
processing the one or more NIR greyscale images and the one or more visual images of the first surface of the wood product to generate NIR greyscale and visual superimposed images of the first surface of the wood product indicating different moisture levels and visual elements in the first surface of the wood product;
assigning a grade to the wood product based on the identified moisture levels and visual elements in the first surface of the wood product; and
based, at least in part, on the grade assigned to the wood product, taking one or more actions with respect to the wood product.
2. The method for detecting moisture levels in wood products of claim 1 wherein the one or more sources of illumination include one or more LED light sources.
3. The method for detecting moisture levels in wood products of claim 1 wherein one or more NIR cameras are adjustably positioned to capture one or more NIR images of the illuminated surface of the wood product.
4. The method for detecting moisture levels in wood products of claim 1 wherein positioning a wood product to be analyzed in the NIR analysis station is accomplished by passing the wood product through the NIR analysis station on a conveyor system.
5. The method for detecting moisture levels in wood products of claim 1 wherein the one or more actions taken with respect to the wood product based, at least in part, on the grade assigned to the wood product, include one or more of:
sorting the wood product into a bin or location associated with the grade assigned to the wood product;
restricting the use of the wood product based on grade assigned to the wood product;
rejecting the wood product based on the grade assigned to the wood product;
sending the wood product back for further processing based on the grade assigned to the wood product;
adjusting one or more processing parameters of a production line based on grades assigned to one or more wood products;
adjusting drying temperatures on a production line based on grades assigned to one or more wood products; and
adjusting drying times on a production line based on grades assigned to one or more wood products.
6. The method for detecting moisture levels in wood products of claim 1 further comprising:
generating a greyscale to color mapping database, the greyscale to color mapping database containing data that maps one or more greyscale values to respective visible colors indicating moisture levels for one or more wood products; and
after processing the NIR greyscale images using the moisture level to greyscale mapping database to identify moisture levels for the first surface of the wood product, processing the NIR greyscale images using the greyscale to color mapping database to generate color-based moisture level images for the first surface of the wood product.
7. The method for detecting moisture levels in wood products of claim 1 wherein one or more visual cameras are adjustably positioned to capture one or more visual images of the illuminated surface of the wood product.
8. The method for detecting moisture levels in wood products of claim 1 wherein the NIR analysis station includes one or more sources of illumination positioned to illuminate two or more surfaces of a wood product and one or more NIR cameras positioned to capture one or more NIR images of the two or more illuminated surfaces of the wood product.
9. The method for detecting moisture levels in wood products of claim 8 further comprising:
positioning a wood product to be analyzed in the NIR analysis station such that the two or more surfaces of the wood product to be analyzed are illuminated by the one or more illumination sources;
capturing, using the one or more NIR cameras, one or more NIR images of the illuminated two or more surfaces of the wood product;
processing the one or more NIR images of the illuminated two or more surfaces of the wood product to generate NIR greyscale images indicating different moisture levels in the illuminated two or more surfaces of the wood product; and
processing the NIR greyscale images using the moisture level to greyscale mapping database to identify moisture levels for the two or more surfaces of the wood product.
10. A method for detecting moisture levels in veneer sheets comprising:
generating a moisture level to greyscale mapping database, the moisture level to greyscale mapping database containing data that maps moisture level to Near InfraRed (NIR) image greyscale values for one or more veneer sheets;
providing an NIR analysis station, the NIR analysis station including one or more sources of illumination positioned to illuminate a surface of a veneer sheet, the NIR analysis station including one or more NIR cameras positioned to capture one or more NIR images of the illuminated surface of the veneer sheet;
positioning a veneer sheet to be analyzed in the NIR analysis station such that a first surface of the veneer sheet to be analyzed is illuminated by the one or more illumination sources;
capturing, using the one or more NIR cameras, one or more NIR images of the illuminated first surface of the veneer sheet;
processing the one or more NIR images of the illuminated first surface of the veneer sheet to generate NIR greyscale images indicating different moisture levels in the illuminated first surface of the veneer sheet;
processing the NIR greyscale images using the moisture level to greyscale mapping database to identify moisture levels for the first surface of the veneer sheet;
providing one or more visual image cameras, the one or more visual image cameras positioned to capture visual images of the first surface of the veneer sheet;
capturing, using the one or more visual image cameras, one or more visual images of the first surface of the veneer sheet;
processing the one or more NIR greyscale images and the one or more visual images of the first surface of the veneer sheet to generate NIR greyscale and visual superimposed images of the first surface of the veneer sheet indicating different moisture levels and visual elements in the first surface of the veneer sheet;
assigning a grade to the veneer sheet based on the identified moisture levels and visual elements in the first surface of the veneer sheet; and
based, at least in part, on the grade assigned to the veneer sheet, taking one or more actions with respect to the veneer sheet.
11. The method for detecting moisture levels in veneer sheets of claim 10 wherein the one or more actions taken with respect to the veneer sheet based, at least in part, on the grade assigned to the veneer sheet, include one or more of:
sorting the veneer sheet into a bin or location associated with the grade assigned to the veneer sheet;
restricting the use of the veneer sheet based on grade assigned to the veneer sheet;
rejecting the veneer sheet based on the grade assigned to the veneer sheet;
sending the veneer sheet back for further processing based on the grade assigned to the veneer sheet;
adjusting one or more processing parameters of a production line based on grades assigned to one or more veneer sheets;
adjusting drying temperatures on a production line based on grades assigned to one or more veneer sheets; and
adjusting drying times on a production line based on grades assigned to one or more veneer sheets.
12. The method for detecting moisture levels in veneer sheets of claim 10 further comprising:
generating a greyscale to color mapping database, the greyscale to color mapping database containing data that maps one or more greyscale values to respective visible colors indicating moisture levels for one or more veneer sheets; and
after processing the NIR greyscale images using the moisture level to greyscale mapping database to identify moisture levels for the first surface of the veneer sheet, processing the NIR greyscale images using the greyscale to color mapping database to generate color-based moisture level images for the first surface of the veneer sheet.
13. The method for detecting moisture levels in veneer sheets of claim 10 further comprising:
generating a greyscale to color mapping database, the greyscale to color mapping database containing data that maps one or more greyscale values to respective visible colors indicating moisture levels for one or more veneer sheets; and
after processing the NIR greyscale images using the moisture level to greyscale mapping database to identify moisture levels for the first surface of the veneer sheet, processing the NIR greyscale images using the greyscale to color mapping database to generate color-based moisture level images for the first surface of the veneer sheet.