By James F. Manji
A mere three years. That's how long Pepperidge Farm, the well-known maker of sinfully good cookies, snacks, and other foods, expects it will take for an award-winning robotic line to pay for itself.
Nimble FlexPicker robots from ABB Inc. snatch cookies from a conveyor at the rate of 150/min and gently place them five high into paper cups. Vision systems from Adept Technology aid in the task. The Robotic Industries and Automated Imaging Association thought so highly of the results that it recently honored the food maker with a User Recognition Award.
It's easy to see why the Pepperidge Farm unit of Campbell Soup Co. made a sizable investment in automation technology.
The company confides that workers had a tough time loading the flimsy paper cups fast enough, and quality was wanting with manual methods. Indications are that more and more firms are using robots to address similar problems. "Their experience using robots in cookie packaging is typical of the kinds of things that forward-looking companies will be using robotics for in the months ahead," predicted RIA President Kevin Ostby at the Award ceremony.
A variety of foods, pharmaceuticals, medical devices, home products, and household goods now tumble into packages via robotic devices. Reasons for going with the robotic approach include a requirement for a guaranteed level of sanitation during packaging, according to Rick Tallian, a packaging systems manager for Manufacturing and Consumer Industries at robot maker ABB Inc., New Berlin, Wis.
Robots are also getting the call when "the operation can cause injury to a human operator from ergonomic issues such as repetitive motion/stress issues," explains Tallian.
Of course, robots are still going into niches where hard tooled or fixed automation doesn't work well. Robotics can sometimes better tolerate variations in product size and can handle delicate products that may crumble if subjected to traditional pushing, guiding, and collating techniques. Product lines having numerous variations continue to be candidates for a robotic approach, as are those with variations in their packaging. And many manufacturers use robotics when they expect future product configurations to change in ways that could be hard to predict. This is particularly true in consumer goods, says Tallian, where product marketing drives the product and the packaging.
Manufacturers increasingly view robotic assembly as a way to avoid mix-ups in products produced with numerous options. "If there are two slightly different parts for a car's engine, using the wrong one could cause an entire automotive assembly line to shut down," explains Mark W. Senti, president of GSMA Systems Inc., Palm Bay, Fla. "In the pharmaceutical industry, a robotic-packaging system equipped with vision can prevent serious blunders that might otherwise lead to the wrong dosage of prescription drugs."
Adds Jack Justice, robotic systems manager at Motoman Inc., West Carrollton, Ohio, "Mean time between failures (MTBF) exceeding 50,000 hr make industrial robots reliable, efficient alternatives to custom-designed solutions." The ability to handle oddball physical constraints is another plus. "A multiaxis robot can insert product into containers even when the packaging sits at an angle to the floor. And the same robot controls that handle product during manufacturing can also place it into packages and palletize it at the shipping docks," says Justice.
Recent advances in robotic technology have simplified the process of implementing packaging and cartoning applications. Fanuc Robotics N.A., for example, has developed software designed specifically to program palletizing applications. "Major advances in machine vision let us integrate robots with packaging systems without collating or product aligning devices," explains Matt Job, palletizing and packing engineer for Fanuc in Farmington Hills, Mich. "Eliminating these peripheral devices lets us cut the cost of the overall systems."
Steady increases in computer power are responsible for more able robotic controls. Says ABB's Rick Tallian, "Low-cost computing power has led to better servocontrol for robotics and vision guidance. An example is in our IRB340 FlexPicker robot. It hits 300 cycles/min for pick-and-place operations. We are also developing various solutions with integrated vision for robot guidance and inspection."
Better electronics are also letting one controller handle up to three robots, a configuration that simplifies collision avoidance in a multiple-robot cell. "Robotic simulation software lets users model the process, optimize the layout, and verify cycle times to reduce risk in these applications," explains Joe Campbell, a vice president for robot maker Adept Technology Inc., San Jose.
From candy bars to 5-gallon drums
One advantage of a robotic-packaging system is labor savings. A rule of thumb is that a robot replaces one person for about every 50 containers packed, depending on the weight, size, and package qualities. This according to William H. Goodman, president of Goodman Packaging Equipment Co., Waukegan, Ill.
"We've found this to be the case in top-load robotic placement of packages into shipping containers," explains Goodman. "We also see it in integrated solutions to load or unload packages into cases, trays, cartons, totes, and so forth."
As an example, Goodman points to one case where the firm's equipment plops 5-gallon liquid pouches into containers at 20 bags/min and replaces two people/shift. At another plant, a robot packing stand-up pouches into cases at 100 pouches/min replaces three people/shift. And a different Goodman machine packing candy bars into trays at 500/min replaces five people.
The company makes about 75 integrated systems annually and has over 750 packaging systems in operation. It specializes in robotic-packaging machinery where a typical task is to erect or form the shipping container, pack, and then seal it.
Head-count reductions aren't the only motivation for installing Goodman's equipment. Robotic packers can be a space-efficient way of getting more production from the same amount of floor space. "One customer could only fit four people into an area that was capable of packing 400 packages/min," explains Goodman. "The robotic packer replaced these people in the same footprint and packed up to 600 packages/min."
Other vendors see robotic-packaging systems installed for the sake of quick response to market conditions. "As product life cycles shrink, automation must be redeployed quickly," says Adept Technology's Campbell. "The programmable nature of roboticpackaging automation is a clear advantage. In addition, most and automated assembly lines handle multiple products or product configurations. Promotional contents, private labeling, and point-of-sale packaging all contribute to a need for flexible robotic lines."
Finally, robotic-packaging systems are going in when speed of implementation is important. "Systems that have been properly specified, accurately engineered, and well tested offline can often be up and running within one week or less," says Goodman. "The degree of system integration with conveyors and other equipment can dictate start-up time. Once they are running, the machines work 24/7 98% of the time or better when well maintained. Still, I have to remind customers once in awhile that machines occasionally fail and require maintenance."
Nobody knows the troubles I've seen
Integrators who set up robotic systems say they repeatedly see many of the same mistakes made by firms specifying packaging automation. One of the biggest problems: Giving systems integrators a process or part flow scheme that isn't complete. This often happens when aspects of the production process exist as tribal knowledge and are not documented. The result is a lot of wheel spinning before implementers noodle out the truth. (One other observation is that ISO 9000 companies tend not to have such difficulties.)
Though it may seem an obvious mistake, some manufacturers fail to give integrators a system specification at all. These firms also tend to have unrealistic expectations of installation time and budgeting for automation requirements.
The proscription for avoiding such difficulties, say integrators, is to stay involved during the design process. Also important is to find an integrator that's done applications resembling the one at hand. Some integrators, for example, have expertise in specific kinds of cartoning lines.