Advancements in robotics are about doing more with less, and about copying human arm movements for maximum efficiency. But robots do more than human arms can – they lift more, faster and tirelessly.
Greater flexibility, lighter weight materials, new technical advances in sensors, a finicky retail environment where purchasing managers are buying less but more variety (mixed palletizing), and a move into new industries like food processing (hygienic design) – these are some of the dominant trends in robotic gripper technology today.
The laws of geometry have not changed since the Greek mathematician Euclid wrote them down in The Elements in 300 BC, and they remain the basis for how today’s robots and their grippers function. After all packaging is all about fitting something into a box, and geometric principles dictate how many can fit.
But gripper technology has come a long way since the days of Euclid, with literally hundreds of different solutions for all imaginable industries. And in most industries, there is an increased pressure to come up with cost-saving alternatives to increase profitability.
This is what is driving developments in robotics and gripper technology as automated tools for packaging and sorting find their way into new applications, or move upstream into production.
“The human hand is the most flexible tool you could ever think of,” says Dr. Andreas Wolf of robomotion, a robot technology consultancy in Germany, and author of the definitive book Grippers in Motion. The book provides a comprehensive guide to automation processes involving gripping and manipulation.
“But unfortunately, robotic hands with all their sensors, joints and flexibility tend to be very expensive, and not every process needs the flexibility of a human hand,” says Wolf. “At the moment most industrial manufacturing that uses robots tend to have a dedicated gripper for the task.
“At the same time, the intelligent gripping systems and service robots that we have today are the early signs of a new, more flexible automation technology, which will be capable to auto-adapt to changing environments. Applications in the food processing industry, pharmaceuticals and agricultural production are not yet standard, but they do offer a growing market for automated solutions in the near future.”
As an example of grippers that can adapt to their environment, researchers at New York University’s Courant Institute have developed a new kind of gripper they describe as reactive. It responds to stimuli from its sensors they way a hand would from nerves, and changes its grip accordingly.
But in general, the size and shape of robotic grippers depend in great measure on what it is that they are intended to grip. There are grippers that stack, grip, suck, force-fit, or form-fit, single grip or multi-grip. Some are purely mechanical. Others use vacuum technology.
And as consumer goods manufacturers are increasingly making products in every imaginable shape, material and size, the robotics have to become increasingly sophisticated.
“Cycles are going faster and faster today,” says Peter Tell, PIAB’s Chief Technical Officer who invented the coax multistage vacuum cartridge ejector system that is particularly suited to object picking and palletizing. “Every manufacturing company wants to increase production at a lower cost. It is about doing more with less.”
A well-known paint and coating manufacturer in the U.S. installed a coax system on one of its packaging robots and has improved its operation with higher line throughput at a lower cost.