Machine Vision

 

The New Zealand dairy industry is the country’s top export earner, worth over 6.3 billion NZD (3.2 billion EURO) per year. New Zealand dairy exports account for 33% of the world's trade in dairy products. The shipment of milk to far-flung markets is most cost-effectively done by removing all of the liquid and transporting the milk in powder form. Machine vision has a small but important part to play in the business of milk powder packing.

Four years ago, Avalon Engineering, a specialist powder packing machine supplier and part of the global GEA group, was given a challenge. Fonterra, the largest dairy cooperative in New Zealand, wanted to jointly develop a solution to reduce or eliminate manual labor from packing rooms. This project was necessary for reasons of both labor savings and food hygiene and was termed “lights-out packing”. Avalon contacted ControlVision, an Auckland-based specialist supplier of machine vision and robot technologies, for help with the project.

Milk processing is already heavily automated - from receiving the milk from the farm and turning it into powder in large driers, to high-speed precision metering of the powder into 25 kg multi-layer plastic or paper dairy bags, and to the sealing and robotic palletizing of the bags. However, one outstanding problem remained - how to retrieve empty 25 kg dairy bags from a pallet and automatically feed them to the filling machine. The empty dairy bags are manually stacked onto pallets by the bag supplier, so their position on the pallet is inconsistent. Machine vision guidance provided the answer to locating the bags.

The Avalon solution includes a custom Cartesian “destacker” robot fitted with a PC-based vision system. The vision system uses a Basler A622f FireWire camera, selected for its robust mechanical design and high quality imaging performance. The machine vision library is Cognex’s VisionPro®, running PatMax® pattern recognition software. PatMax was chosen for its ability to locate bags despite unpredictable positioning and lighting. The entire application runs in the ControlVision VisionServer framework.

This combination of high-performance Basler cameras, Cognex VisionPro software, and the ControlVision VisionServer application has met the requirements of a solution expected to be 100% reliable 24/7 without operator intervention. This system is now successfully exported world-wide through the GEA group.

More product information:
Cognex VisionPro
ControlVision VisionServer


For more information, please contact us at +49 4102 463-500 or e-mail us at bc.sales.europe@baslerweb.com.