A new device for the nondestructive testing of standing trees is presented. It is based on the simultaneous measurement of the velocities of waves by a number (8 - 64) of sensors around the tree. The sensors are coupled to the wood by metal pins causing only minimal damages, if any at all, to the tree. The waves are induced mechanically by a tap on each sensor. The measurement of one tree takes around 20 to 30 minutes. The result, a 2-dimensional tomogram of a cross-section of the tree, is displayed immediately on the screen of a handheld miniature computer. Results are presented for a range of timber species with cavities, decay, and cracks. Defects as small as 5 cm in diameter are identified and located. The device appears to have promising applications in the inspection of roadside trees and of valuable logs and standing forest trees.
Publication Source: Proceedings of the 12th International Symposium on Nondestructive Testing of Wood University of Western Hungary, Sopron, 13-15 September 2000, ISBN 963 7180 88 5 Publisher: University of Western Hungary, H 9400 Sopron, P.O.Box 132, FAX: +36 99 311 103
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