Three dimensional knot models based on surface laser scanning
2015 (English)In: Proceedings 19th International Nondestructive Testing and Evaluation of Wood Symposium Rio de Janeiro, Brazil, 23-25 September, 2015. / [ed] Ross, Robert J.; Gonçalves, Raquel; Wang, Xiping,, Madison, USA: USDA, Forest Service, Forest Products Laboratory , 2015, Vol. 19, 83-90 p.Conference paper (Refereed)
Most machine strength grading methods of today result in limited grading accuracy and poor yield in higher strength classes. A new and more accurate grading method utilizing laser scanning technique to determine the in-plane fibre directions on board surfaces was recently approved for the European market. In this, however, no consideration is taken to the out-of-plane direction of the fibres. A first step towards scanning-based 3D models of the fibre orientation is the establishment of 3D knot models. In this investigation laser scanning was used to identify knot surfaces on longitudinal board surfaces. By means of developed algorithms knot surfaces that belonged to the same physical knot visible on different sides of the board were identified. All knots with surface areas larger than 100 mm2 were correctly identified and modeled in 3D. This is a promising starting point for further development of the new grading method based on laser scanning.
Place, publisher, year, edition, pages
Madison, USA: USDA, Forest Service, Forest Products Laboratory , 2015. Vol. 19, 83-90 p.
, General Technical Report, FPL-GTR-239
structural timber, knots, laser scanning, tracheid effect, local fibre direction, diving angle
Other Civil Engineering
Research subject Technology (byts ev till Engineering), Civil engineering
IdentifiersURN: urn:nbn:se:lnu:diva-52060OAI: oai:DiVA.org:lnu-52060DiVA: diva2:919276
19th International Nondestructive Testing and Evaluation of Wood Symposium, Rio de Janeiro, Brazil, 23 -25 September, 2015.
Ej belagd 201604222016-04-132016-04-132016-05-27Bibliographically approved