An X-ray system for measuring and grading corn-on-the-cob (sweetcorn)
Working with a UK manufacturer of food handling systems, WyeTec assisted in the development of a product to
automatically measure and grade corn-on-the-cob whilst it was still "in the leaf".
Reducing waste through early inspection
When not in season, most of the corn-on-the-cob consumed in the UK is imported, predominantly from Southern
African countries. The corn is shipped whilst still "in the leaf", as this acts as a natural protective wrapper.
Corn-pickers feel the cobs prior to picking to gauge whether they are of sufficient size/quality, but without being able
to strip the leaf and see the cob, the grading is far from perfect. The result is that large quantities of bad product are
shipped 1000s of miles, only to be rejected at the packaging plant.
The aim of the project was to develop a system that
could automatically detect damaged or undersize fruits whilst they were still in the leaf. These could then be used locally
to where they are harvested - for animal feeds, maize products or biofuel production - rather than being needlessly transported.
Detection and analysis:
The solution used a monoblock X-ray source and area-scan detection to collect digital images. These were then analysed using an
inspection routine developed in Scorpion Vision, which measured the cobs, identified breaks/contaminants and issued a pass/fail signal.
Key to the inspection system was understanding how to optimise the performance of the system, by presenting the best possible image to the
analysis algorithms. Careful selection of X-ray and imaging parameters enabled the analysis to focus on the fruit body, rather than the