| 摘要 |
<p>A method for determining warp potential of wood. One embodiment comprises nondestructively obtaining lengthwise shrinkage rates and grain angles of wo od - such as trees, logs, or lumber - then determining warp potential of the wo od based on the lengthwise shrinkage rates and grain angles. The method typical ly comprises measuring plural lengthwise shrinkage rates and plural grain angle s to determine warp potential. Where the wood comprises lumber, lengthwise shrinkage rate and grain angle measurements typically are made on at least o ne major planar surface of the lumber at at least two measuring points separate d by a predetermined distance, such as at substantially one-foot intervals alo ng the lumber. Particular embodiments of the present invention determine lengthwise shrinkage rates using electromagnetic energy, acoustic energy, an d combinations thereof. Working embodiments of the method use ultrasound energ y to determine lengthwise shrinkage rates and grain angles. Another embodiment of the present invention comprises providing a piece of wood having at least one major planar surface, positioning the piece of wood adjacent to a device for imparting energy through the piece of wood to determine at least one lengthwise shrinkage rate and at least one grain angle. Embodiments of the presentinvention are automated and can be adapted to industrial processes fo r commercial production of lumber or for forest management practices. Warp potential can be determined using a finite element model (FEM).</p> |
