Vision Controls automates vial inspection

A vision system normally used for the high speed inspection of turned and formed metal components has been adapted for the task of inspecting glass phials used for drug delivery in the pharmaceutical industry.

The Checkfast inspection system, manufactured and marketed by Vision Controls, is required to inspect vials at a rate of 3 per second; it also has to be capable of inspecting a wide variety of products, ranging from small flange form tubes to squat screw-necked bottles.

Using the steel belt transport mechanism of the Checkfast system it is possible to 'back light' the glass vessels to detect cracks, chips and dirt and to make the necessary measurements of critical dimensions. The multi-camera system acquires plan and side views of the product, while Vision Controls uses cameras placed at specific angles to view the flanges on the flange form product.

The inspection of the flanges was a particular challenge due to the irregular nature of the flow of glass in the flange forming process. However, a special algorithm was written by the Vision Controls software team that closely tracked the edge of the flange. This enables repeatable inspection of this difficult feature.

This pharmaceutical-based Checkfast system is the first of the MKIII generation models to be shipped and includes several advanced features to assist in the automation of the inspection process: hopper, bowl and feed speeds are digitally controlled via the image processing interface. This means that the correct feed settings can be saved with the inspection set-up data for specific products.