Enhanced vision and software technologies continue to boost production efficiencies for pick-and-place robotics.

Pick-and-place robotics hold a venerable place in most processing and packaging lines. While the equipment has been around for some time, the technology continues to improve and its use is expanding into new tasks.

Because they can be easily reprogrammed, robots have become a highly flexible tool in today’s fast-changing manufacturing environment. And, with new functionalities, robots are also bringing automation to areas that used to require a human touch. Plants that are focused on ergonomics and worker safety are finding new uses for pick-and-place robots, especially for tedious and/or repetitive tasks.

And, as with any evolving technology, costs are leveling out even as robot functionality continues to climb.

Robotic technology suppliers continue to fine tune vision software and vision apparatus to further increase line speeds and production accuracies.

Vision and vision controls are tantamount to production efficiency. “The more intelligent-sensing the robot is capable of, the more complex the handling task can be,” comments Roland Czuday, product manager, Delta Robot Systems, Sigpack Systems AG. “Thus, the development of highly sophisticated control and vision systems, combined with precise gripping technology is one prerequisite to fulfill the growing demand of format flexibility, distinguishing pack styles, careful and gentle product handling and high-volume product rates.”

Camera-based vision guidance technology is getting more popular, according to Hans de Koning, president, Flexicell Inc. “The controls themselves are also getting more sophisticated,” he says. “As PCs get more powerful and since most of the vision systems use PC, they are getting more powerful. Software is evolving. It is now easier than ever to work with and set up.”

One of Flexicell’s latest developments is a standard “off the shelf” robotic cup case packer. As de Koning describes, the robot will pick the cups directly from the filler and place them into an erected case. It will “collapse” the center lines of the cups in two directions (with a patented gripper) to fit more cups into a smaller case by overlapping the lids of the cups.

Robots are flexible, but they haven’t always been flexible and fast. Today, speeds have ramped up. A vision-guided pick-and-place robotic solution from BluePrint Robotics achieves in access of 140 picks per minute with a single gripper, depending on the product. Speeds dramatically increase with multiple pick grippers and/or multiple robots. The system can handle multiple infeeds and is suitable for creating variety packs or lunch kits with different pre-packaged foods.

On the control side, Czuday advocates the use of flexible robotic systems capable of allowing the implementation of complex movements. These special functions should not necessarily be programmed, but should be modularly “plugged” together out of a given function library, says Czuday. “Vision systems are capable of gathering more and more information of the incoming products: shape, dimensions, color and statistic functions allow the implementation of sophisticated sorting strategies and ensure stable and constant image processing,” he says. “Fully automated, controlled and recorded processes are essential in the pharmaceutical industries, hence equipping packaging systems with such features is paramount.”

On the surface, robotic systems and components today appear to be controlled in much the same way as they have been for the last few years, but there have been been dramatic changes. “The move from a centralized cell controller to distributed or embedded processors has changed the landscape of factory automation,” says Tim DeRosett, manager, global packaging business, Adept Technology Inc. “Many suppliers are touting ‘smart’ devices with on-board processors. This provides flexibility, which is required by many applications, and scalability, which the competitive market is demanding. Customers want enough to do the job and are not willing to pay for more.”

Technological advancements have driven the innovation of controls and robotic design. Powerful embedded processors are now readily available and inexpensive. This development, coupled with the ongoing trend of smaller electronic devices, have made it practical to embed controls inside robots and enabled significant improvements in servo-control. “More powerful servo-control systems provide higher performance resulting in more picks per minute, therefore fewer robots are required for some applications,” says DeRossett. “Embedding control systems into the robot reduces the cost of implementation and ownership for customers.”

Servo-control software has also advanced dramatically. “A robot’s performance can only be as good as the motion-control system’s ability to control and coordinate the robot axes (or joints),” observes DeRosett. “Recent advancements provide tighter control of servo-axes and enable servo systems to adapt to changes in inertia, which can result when picking up product. The result is significantly better performance.”

Today, flexibility on the factory floor is a must. Complex product mix and tight inventory control often requires weekly or daily product changeover. Flexible automation is the key to success for these applications. “By programming and tooling robots to run multiple products—often tens and sometimes hundreds—changeover time can be dramatically reduced,” says DeRosett. “This flexibility allows companies to install fewer lines on less floor space than with traditional hard-automation.”

Adept recently launched the Adept Cobra i-series system, which is the first SCARA robot with complete controls embedded into the robot base. Embedded controls mean easy installation: the robot is bolted in place and connected with the external emergency stop. As soon as power is applied, it’s ready to go.

Other developments are also worth mentioning.  Among them is the robotic hybrid Model 360 pick-and-place case packer from A-B-C Packaging Machine Corp. The machine is PLC controlled and the packing operation and robots are servo-driven.

“The pick-and-place technology provides smooth and gentle packing of a variety of products into shipping cases or trays, in single or multiple layers, and the variety of gripper mechanisms available make this machine adaptable to a range of products. All pack patterns are preprogrammed, and the machine can be programmed for new pack patterns, product types, either at the control panel or remotely,” says Bryan Sinicrope, the company’s director of marketing and OEM sales.

ABB recently introduced the modular IRC5, which has the capability to control up to four fully coordinated robots and 12 external axes with one robot controller and MultiMove functionality. "This means less floor space is used and the controls are modular," says Mike Crane, business development manager, consumer industries, ABB Inc.

The IRC5 uses just one FlexPendant per control module, whether controlling one or four robots. Connection is via a single cable, helping to minimize cable clutter to a cell. The IRC5's improved ease-of-use for programming also makes use of a direct link with RobotStudio off-line programming tools.

ABB also released an enhanced version of its PickMasterÝ industrial IT software (v. 2.3), which helps guide robots in the packaging process. The PC-based software uses a high-performance vision system to pinpoint random objects. It identifies and transfers 360-degree random objects in 50 to 200 milliseconds. Application projects are precisely configured and calibrated using comprehensive graphical configurators. PickMaster can control up to eight robots and eight cameras, working together in one application or in multiple independent processes.

The exploration of new fields continues to be one of the main challenges for robotics development. “Pick-and-place applications in the food industry are one of these new fields, favored by the fact that the costs for robot packaging lines are constantly going down, whereas labor costs are increasing,” says Sigpack’s Czuday.

The capabilities of pick-and-place systems determine the complexity of the tasks which can be carried out, he adds. “Hence, the approach is not market-driven, but technology-driven. In the packaging sector, basically all manual high-volume operations are suspect to be automated, especially if those operations are located between two already automated processes or take place in a harsh environment.”  F&DP

Joanna Cosgrove, a freelance writer based in Media, Pa., has been writing about various aspects of packaging, product design and product manufacturing since 1996. Her e-mail address is joannacosgrove@comcast.net.

The following companies helped with the research of this article: