Robot takes on fast-moving packages

By KATRIN STUBER

 IN THE order-picking warehouse at meat processing company, Nortura, the overriding concern is how to get freshly processed and packaged meat to the customer. About 140 employees currently sort customer orders. The company, Norway’s leading meat processor, has a total workforce of 5,000, with 750 employees at the East Plant in Tonsberg. The company supplies some 500 different meat products throughout Norway. Only a small percentage is exported.

For some time now they have had a new colleague: a KUKA KR 180 PA robot. This palletising robot is capable of stacking europallets up to 3 m net height. State-of-the-art materials (carbon fibre composite CRP) make the robot extremely light, without sacrificing high stiffness.

The robot takes care of the so-called “fast movers”. This is the name given to the goods that are ordered most often, and which are consequently dispatched in large numbers.

Sausages, patés and minced meat make their way along conveyors to the loading ramp and from there into the awaiting trucks. Which products are considered as “fast movers” varies according to the season. Midsummer festivities in Norway, for instance, involve lots of barbecues. The crates that the robot places on the conveyor in June thus contain large quantities of packaged mince, steaks and sausages.

“We have five lines where the most frequently ordered goods are produced and dispatched,” explains Jon Brekke, project manager for the order-picking robot at Nortura in Tonsberg. The quantities involved are subject to seasonal fluctuation and can be quite considerable. In midsummer, 500 to 900 tonnes of meat products leave the order-picking area in Tonsberg every week. Of this, the robot handles about ten tonnes a day. “In order to be able to order-pick these large quantities of goods as quickly as possible, we need the robot. It works 24 hours a day, seven days a week.”

Five different products can currently be order-picked on the KUKA robot system. However, the system has been designed to be so flexible that it can easily adapt to changing product lines depending what is much more in demand during a particular season.

Taking on two jobs

The palletising robot, a KR 180 PA, has not just one, but two jobs at Nortura, where it is integrated into a system concept from the robotics and plant & systems engineering supplier. A forklift truck fetches pallets of crates, each containing large quantities of unmixed products. According to the customer order, the robot is told by the warehouse’s central computer which product to pick up next. The robot then checks for itself whether it is holding the correct product by holding the crate against a scanner. Each crate is labelled with a barcode identifying the contents of the crate.

A new code is then applied to the crate. This identifies the customer for which it is destined. The robot then sets it down on a conveyor, which transfers it to the next storeroom. There it is scanned again and transferred to the correct destination determined according to the code – i.e. the loading ramp of the truck that will transport it to the customer who placed the order.

“The most challenging task in the implementation of the system was unquestionably designing the gripper in such a way that it recognises and can grip the plastic boxes in all their different positions,” explains Frode Grimsbo, service engineer at KUKA. For this reason, the gripper was fitted with an ultrasound sensor system for checking distances. This allows the robot to be guided at the fastest possible speed to the first pick position. Once it has reached the crate, the clamping gripper initially remains loosely closed until it has found the ideal gripping position. Only then doesAir Zoom Pegasus 35