Sizing up the sorting issue

Reducing the need for manual sorting is one of the big challenges for automation systems, and the development of ever more advanced machine vision technology is playing a key role in meeting it.

Now a team of specialists in the field has used state-of-the-art image-processing techniques to help the retail sector reduce the time and cost needed to deal with one of the most basic tools of its trade - the humble size tag.

High-street shops use the small coloured plastic tags with white numbers - known as cubes in the trade - on the hangers of clothing in stores.

Once an item is purchased and the unwanted cubes removed from the hanger, they must be collected from each of the stores and sent to a central depot where they must be sorted before they can be reused.

In the past, this has been a very time-intensive process involving tens of operators who were required to visually examine each of the coloured tags and place them into bins according to the numbers printed on them. Seeking to automate the procedure, one high-street chain commissioned engineers at Oxford-based Industrial Vision Systems and Birmingham-based RNA Automation to develop a system that could sort 300 cubes in one minute, removing the need for repetitive manual labour.