The new robot: fast, flexible, functional and affordable: enhanced vision and software technologies continue to boost production efficiencies for pick-and-place robotics

Food & Drug Packaging, March, 2005 by Joanna Cosgrove

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.

Looking good!

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 bee 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.

Get 'on board' with controls

On the control side, Czuday advocates the use of flexible robotic systems capable of allowing the implementation of complex movements. These special tractions 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."