A Technique to Quantify Damage of the Flute Profile in the Mid-Plane of Corrugated Fibreboard

This research presents a technique to quantify flute damage in corrugated fibreboard by conducting image analysis on digital image of flute profiles obtained from thinly laser cut samples. Sample preparation by laser cutting was validated to ensure no additional damage on the flute occurred, by analysing the surface profile of creased corrugated board before and after the laser cutting process. The analysis proves sample preparation does not significantly affect the flute profile. After imaging the laser cut samples, Skeleton analysis was used to derive an accurate digitized profile of the flute shape. To characterise the level of damage on the flute profile, a Similarity Factor (SF) was introduced to quantify the difference between test-sample flute profiles relative to a reference flute profile. Validation of this analysis technique was done by generating known images of flute profile with variations that include distortions that could occur to corrugated fibreboard. These images were then fed into the Skeleton analysis and the results, were compared with the original profile. This comparison shows good accuracy with SF of at least 0.9986 between the initial and skeleton-analysed flutes. A demonstration of the Skeleton analysis on an actual flute profile shows that the SF reduces as the crushing damage increases, showing it could be a useful technique to enumerate damage to corrugated board through manufacture, conversion and use. Future work will focus on how to match the SF with the board properties.