Vacuum gripping using compressed air has been working for decades. Why do companies stick with this technology, even though compressors, pipework and consumption at every gripping point cost energy and effort, and where is this cost most often underestimated?

Because compressed air works. And quite reliably at that. Design engineers are familiar with technology, the components are readily available, and people know how to design a system using it. I can understand that well.

What surprises me, however, is this: in industry, every additional step in the process is scrutinised, and every unnecessary use of energy is to be avoided. Yet when a robot is required to grip a component using a vacuum, compressed air is often already part of the design before anyone has even asked about an alternative.

Added to this is the fact that investment and running costs are often considered separately. The machine manufacturer must supply a functioning system. The cost of compressed air over ten or fifteen years is borne later by the operator. And the operator, in turn, has little interest in retrofitting a system that is already in operation, as long as it is producing reliably.

We’re not talking about a single gripping operation here. A robot might grip ten times a minute, for several thousand hours a year. A single gripping point can become many; a single system can become entire production lines. That all adds up.

I don’t want to talk anyone out of using pneumatics if it is the best solution for the application. But I think we should at least check whether we need it at all.

Electric vacuum generation directly at the gripper sounds like a fundamentally different approach. For which applications is it particularly suitable, and where does it still face technical limitations – for example, with workpieces, surfaces or cycle times?

The interesting thing is: when we talk about electric vacuum grippers, the first thing we often hear is: ‘We’ve heard of them – they’re too slow.’ And that’s often the end of the discussion. And yet this person hasn’t even looked at our technology.

Take our G-VAC PS, for example. It doesn’t have a vacuum pump at all. It rests on the workpiece with its suction cup, a valve closes, and the vacuum is created as it is lifted. This works on largely sealed surfaces such as glass, metal or plastic.

A distinctive feature of our technology is the drive mechanism. We use a thin wire made from a nickel-titanium shape-memory alloy. A short electrical pulse causes it to contract, generating surprisingly high forces in the process. This enables us to create a very compact and lightweight actuator mechanism, without the need for a motor or gearbox.

And the key factor for industrial applications is this: we can grip the workpiece very quickly and release it just as quickly. It is precisely this release function that is often underestimated in electric vacuum grippers. If a workpiece is only released after two or three seconds, you cannot operate a high-speed production line with it.

We have already demonstrated that our principle works even with industrial cycle times in a joint development project with a car manufacturer. Four grippers picked up a door panel, moved it very dynamically and set it down again. Around ten times a minute, for days on end, purely electrically.

Of course, this doesn’t work with every material. Air can seep through porous or slightly leaky surfaces. That’s why we’ve developed the G-VAC AS, which actively stabilises the vacuum using a small electric pump. However, when dealing with very high leakage rates – for example, in highly air-permeable cardboard packaging – we’re still reaching the limits of our current pump capacity.

I also find a completely different application particularly exciting: humanoid robots. In this case, the power comes from a rechargeable battery. Our gripper is very light, and the valve actuator requires only short electrical switching pulses. It does not need a continuous current to maintain the switching state. Suddenly, these are characteristics that become particularly interesting for mobile robots.

And that is precisely what makes our work so appealing. We know what technology is capable of. But through new applications, we are constantly discovering where it offers a particular advantage.

What specific solution will you be showcasing at HM27, and what will visitors be able to try out for themselves at your stand?

In the Application Park, we’ll be demonstrating our pneumatic-free gripping technology in two automated applications. The focus will be on our G-VAC grippers and the Softgrip, which we hope will open up new possibilities for gripping tasks.

It’s important to me that visitors see the grippers in action. How quickly is a workpiece picked up? How securely is it held? And above all: how quickly is it released again? This can best be assessed by watching a live application.

Incidentally, the HANNOVER MESSE is a special place for us. It was here in 2018 that a car manufacturer first became aware of an early prototype of our technology. This later led to a joint research project. Back then, the question was still whether the gripping principle was even suitable for industrial applications. Now we’re returning as a company with the products developed from that research.

I’m most looking forward to visitors who come to us with specific questions. What happens in the event of a leak? How quickly can the gripper actually switch? Can it pick up my component too?

That is exactly what we would like to find out together. We cannot answer every question straight away either. That is why we test real workpieces in our own application laboratory, measure their vacuum behaviour and examine the process conditions. This enables us to determine where our technology can be used effectively and where it cannot.

After all, a new technology does not necessarily have to be the best solution for every task. But if we do not even investigate it, we will never find out what is possible with it.

Contact person for PR, trade show booth, and marketing:
Roger Kautz
Tel +49 176 62 944 177
roger.kautz-ext@nititec-gripper.de
www.linkedin.com

nititec vacuum gripper GmbH