lnu.sePublications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Automatic detection of pith location along boards of Norway spruce on the basis of data from optical scanning of longitudinal surfaces
Linnaeus University, Faculty of Technology, Department of Building Technology.ORCID iD: 0000-0002-0872-0251
Linnaeus University, Faculty of Technology, Department of Building Technology.ORCID iD: 0000-0002-6410-1017
Linnaeus University, Faculty of Technology, Department of Building Technology.ORCID iD: 0000-0002-8513-0394
2019 (English)In: CompWood 2019 - International Conference on Computational Methods in Wood Mechanics - from material properties to Timber Structures, Växjö, Sweden, June 17-19, 2019, Växjö: Lnu Press , 2019, p. 64-64Conference paper, Oral presentation with published abstract (Refereed)
Abstract [en]

Different mechanical and physical properties of wood are related to the location of pith. Norway spruce wood from the centre of logs, close to the pith, is characterized by lower longitudinal MOE, larger spiral grain angle, and larger longitudinal shrinkage coefficient than what wood farther away from the pith is [1]. Thus, knowledge of pith location along timber boards may play an important role in both appearance grading and in assessment of mechanical properties such as strength [2]. The current work aims to develop an algorithm which is capable of automatically estimating the pith location of Norway spruce boards, along the boards’ length direction, by utilizing optical scanning of longitudinal surfaces. The initial step of the algorithm is to identify defect free sections along the timber board. This is done by utilizing data from tracheid effect scanning of the four sides of the timber board. Thereafter, a continuous wavelet transform (CWT), similar to fast Fourier transform, is applied on grey scale images from scanning, to analyse the variation of light intensity across the four surfaces at selected positions along the board. Obtained local frequencies correspond to the local annular ring pattern on surfaces. Then, assuming that annular growth rings are concentric circles with the pith in the centre, detected local annular ring wavelengths (using CWT) and artificial annual ring wavelengths corresponding to different hypothetical locations of pith are compared, and an optimization procedure is used to identify the location of pith that minimizes the discrepancy between the detected and artificial sets of annular ring wavelengths. Figure 1 shows grey scale images of short segments of longitudinal surfaces, graphs of the detected local annual ring widths, and a photograph of the board cross section where the determined location of pith is marked out. Preliminary results reveal that data from optical scanners and the suggested method allow for accurate detection of annular ring width and location of pith along boards.

Place, publisher, year, edition, pages
Växjö: Lnu Press , 2019. p. 64-64
Keywords [en]
Fibre orientation - modeling and grading of wood
National Category
Wood Science Building Technologies
Research subject
Technology (byts ev till Engineering); Technology (byts ev till Engineering), Civil engineering
Identifiers
URN: urn:nbn:se:lnu:diva-89351ISBN: 978-91-88898-64-7 (print)OAI: oai:DiVA.org:lnu-89351DiVA, id: diva2:1355609
Conference
CompWood 2019 - International Conference on Computational Methods in Wood Mechanics - from material properties to Timber Structures, Växjö, Sweden, June 17-19, 2019
Available from: 2019-09-30 Created: 2019-09-30 Last updated: 2019-10-17Bibliographically approved

Open Access in DiVA

fulltext(513 kB)3 downloads
File information
File name FULLTEXT01.pdfFile size 513 kBChecksum SHA-512
effc3129eabcc90226b38d4a380c3c3a3a0cc52359dffc90da8501fbd8bc461d6156c2abb850cf15e1cba66c25510a9c2b22bedc58d396fa7bc5c2f5e6a21b2f
Type fulltextMimetype application/pdf

Other links

Fulltext

Authority records BETA

Habite, TadiosOlsson, AndersOscarsson, Jan

Search in DiVA

By author/editor
Habite, TadiosOlsson, AndersOscarsson, Jan
By organisation
Department of Building Technology
Wood ScienceBuilding Technologies

Search outside of DiVA

GoogleGoogle Scholar
Total: 3 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 59 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf