For many years, manufacturers of food, consumer products and pharmaceuticals have successfully used traditional hard automation, including wrappers, top loaders and side loaders, to package easy-to-handle products, such as cartons and bottles. However, this type of equipment may not be suitable for some products that are more difficult to handle. Plus, product changeover can be slow and cumbersome with traditional systems, and in today’s retail market, product changeover is the name of the game.
More recently, high-speed picking robots have been used for candies or similar products that are solid, light and not prone to damage when handled at high speeds. But the range of products they can handle is limited.
Difficult-to-handle products have unique challenges that make it harder to use traditional automation or high-speed picking solutions. Problems include maintaining the integrity of looser or more fragile raw products. For example, pizza slices with toppings could sustain damage if the acceleration or deceleration rate is too high, causing the toppings to fly off the pizza. Most products cannot be handled at rates faster than 100 cycles per minute.
Difficult objects
Flexible containers such as bags or pouches can also be difficult to handle using hard automation, and may require larger end-of-arm tools than those used on picking robots. For these and other difficult-to-handle products, such as irregularly shaped bottles or other containers, some manufacturers are turning to high-speed packing robots to fill the gap between traditional automation and high-speed pickers. These robots provide higher payloads, which are often required for end-of-arm tooling that is capable of handling difficult products.
Robotic automation can be used to pick up multiple products as a group, or one at a time. With recent advances in vision technology, robotic packing lines can handle varying or irregular products. For products that are picked off of a moving conveyor belt, the robot takes advantage of the belt’s motion and waits until the product is in front of the robot. It then picks up each individual product with a relatively short and efficient stroke, waits until it has two or more products at a time, and then places them into the container. This reduces the total robot motion, as well as acceleration/deceleration/g-forces on products, while achieving the same throughput as high-speed pickers.
Flexicell, an Ashland, Va., integrator of robotic packaging systems, provided an example of this approach with a turnkey robotic system that it supplied to an electronics manufacturer to pack and palletize fragile products. In Cell 1, a Fanuc M-16iB robot picks up the fragile electronic unit with an end-effector that does not use air, thereby preventing the product from being scratched or dented during handling by the force of air-powered grippers. The product is then presented to a bar code reader, which downloads product information to a label. The label is printed and applied to the outside of the product’s corrugated box.
While the robot holds the product, the end-of-arm tool also retracts a polyvinyl chloride (PVC) plastic bottom tray from a dispenser. In the same cycle, the tool picks a remote control from a tray and packs it into a pocket of the PVC bottom tray, along with the electronic unit. The robot then places the bottom tray into a corrugated box.
In Cell 2, a machine cuts a foam protection sheet from a roll. The robot picks up the sheet and places it on the unit in the box. Next, a second M-16iB robot picks a top PVC tray cover from a dispenser and a CD, or Compact Disc, from a CD dispenser. The CD is packed into the case, followed by a power cord that is one of two colors, depending on the color of the product in the container.
In Cell 3, a four-axis robot loads product literature into the top of the open container. Next, the case is closed, and a bar code reader is used a second time to ensure that the case contains the correct product.
In Cell 4, a Fanuc M-410iB palletizing robot palletizes cased products to one of two pallets, depending on the color of the products.
And they’re out the door. The moral of the story? No matter what the degree of packaging complexity, today’s robotic technology is a valid option.
