0023-6152

AA00697606

4705

Unrefereed

0023-6152

AA00697606

The laminae grading for structural glulam timber is restricted by the bending strength and the ratio of knot diameter according to Japanese Agricaltural Standard (JAS) . However, visual grading is done by workers in most manifacturing factories because there are no clear regulations regarding the measuring method of the ratio of knot diameter. Therefore, the development of a system that could automatically detect knots on a material's surface is very desirable. In this study, a system for automatically detecting the shape (position and area) of knots, which appear on the laminae's surface with a two-dimensional three-Charge Couple Device (CCD) color camera, was developed. The main results obtained are summarized as followes: (1) an automatic detection system for knots appearing on the surface of wood was constructed; (2) this system was composed of a picture-processing device (a two-dimensionial three-CCD color camera and controller), lighting equipment and a personal computer (PC) which controlles all devices and collects sampling data; (3) the system could measure the ratio of knot diameter and detect the existance of knot, and the average measurement time of one image was about 2.6 seconds. Therefore, this system could work at a feed speed of 77mm/s.