Vision systems integrator, Olmec-UK, has designed and installed a machine vision system to determine the integrity of droppers for products such as ear drops at the final packaging stage. The system, built for a leading UK-based manufacturer of over-the-counter healthcare products, checks that the droppers are correct prior to them being placed in the carton with the product.
Using line scan camera technology, it inspects the dropper to make sure that it is fitted with the correct cap and that it is not broken before it is inserted into the final product carton. The droppers are supplied to the packaging line already enclosed in clear plastic packaging. The system can also check that there is a dropper in a packet and that the dropper’s individual packaging is actually present.
The droppers’ individual packaging has a crimp seal running the length of the package. Since the dropper packets arrive at the inspection point in a random orientation, it is possible that the seal could obscure the view into the packet. The solution uses two line scan cameras positioned at 90° to each other, each with its own backlight illumination source, and with a small gap in the conveyor system to allow illumination of the sample as it passes over the gap. The acquisition of an image from each camera for each packet ensures that at least one good image or a composite image will be obtained.
Each line scan camera acquires data at a rate of 200µs/line and the cameras and their light sources are operated in anti-phase so that each camera only receives light from its own light source. The system will operate at up to 180 products per minute for a two camera system.
Both cameras utilise the GigE Vision interface and the complete system is controlled from a custom-designed stainless steel console, using Olmec’s new VP3 modular user-interface for Windows, which is designed for use by production engineers rather than vision experts.
