US 7,149,633 B2 · Displacement method of knot sizing

Abstract

A method of estimating the displaced size of a knot in a lumber piece includes the steps of: translating the lumber piece downstream along a flow path between a radiation source and sensor while simultaneously irradiating the lumber piece with radiation from the first radiation source whereby the radiation is attenuated by the lumber piece; collecting a set of radiation intensity data from the radiation sensor as the lumber piece is irradiated; processing the set of radiation intensity data to sum the radiation intensity data and to provide radiation intensity profiles transversely of the flow path direction and corresponding density profiles transversely of the flow path direction; mapping the density profiles to model a set of three dimensional density profiles of the lumber piece; processing the radiation intensity data to determine a clear wood density threshold value for the lumber piece and a maximum density value of the density profiles; and, computing a ratio of the summed density profile values to the summed maximum density values for the density profiles and multiplying the ratio with the transverse width of the lumber piece.

Claims8

Dependent claims

A method of estimating the displaced size of a knot in a lumber piece comprising the steps of:

a) providing a first radiation source on a first side of a flow path;
b) providing a first radiation sensor on an opposite second side of said flow path and cooperating with said first radiation source;
c) translating the lumber piece downstream along said flow path and between said first radiation source and said first radiation sensor while simultaneously irradiating the lumber piece with radiation from said first radiation source whereby said radiation is attenuated by said lumber piece;
d) collecting a set of first radiation intensity data from said first radiation sensor as the lumber piece is irradiated as it is translated between said first radiation source and said first sensor;
e) processing said set of first radiation intensity data to sum said first radiation intensity data and to provide radiation intensity profiles transversely of the flow path direction of said flow path and corresponding density profiles transversely of said flow path direction;
f) mapping said density profiles to model a first set of three dimensional density profiles of the lumber piece;
g) processing said first radiation intensity data to determine a clear wood density threshold value for the lumber piece and a maximum density value of said density profiles;
and
h) computing a ratio of the summed density profile values to the summed maximum density values for said density profiles and multiplying said ratio with the transverse width of the lumber piece.

6 more elements

A computer program product for use with a device having a first radiation source on a first side of a flow path and a first radiation sensor on an opposite second side of said flow path and cooperating with said first radiation source wherein a lumber piece translates downstream along said flow path and between said first radiation source and said first radiation sensor while said device simultaneously irradiates the lumber piece with radiation from said first radiation source whereby said radiation is attenuated by said lumber piece,

said computer program product comprising:
a) a computer usable medium having computer readable program code means embodied in said medium for causing the sensing of a lumber piece using said first radiation sensor to detect the attenuated radiation and thereby to collect information about the lumber piece;
b) computer readable program code means for causing the collection of a set of first radiation intensity data from said first radiation sensor as the lumber piece is irradiated as it is translated between said first radiation source and said first sensor;
c) computer readable program code means for causing the processing of said set of first radiation intensity data to sum said first radiation intensity data and to provide radiation intensity profiles transversely of the flow path direction of said flow path and corresponding density profiles transversely of said flow path direction;
d) computer readable program code means for causing the mapping of said density profiles to model a first set of three dimensional density profiles of the lumber piece;
e) computer readable program code means for causing the processing of said first radiation intensity data to determine a clear wood density threshold value for the lumber piece and a maximum density value of said density profiles;
and
f) computer readable program code means for causing the computing of a ratio of the summed density profile values to the summed maximum density values for said density profiles and the multiplication of the ratio with the transverse width of the lumber piece.

5 more elements

Dependencies are inferred from the claim text.

Displacement method of knot sizing

Life of this patent

Displacement method of knot sizing

Life of this patent

Abstract

Claims8