Natural solutions

When nature and engineering collide, the results can be astounding. Tim Fryer found out more about Festo's Inspired by Nature concept products.

Around the turn of the millennium Festo started on a project to learn from nature with inspiration coming from one of the owners of the company, Dr Wilfred Store. "We obviously have a large research and development facility capability within the company anyway, which works on fairly traditional lines, but he very much wanted to tap into learning from mimicking nature," said product manager Steve Sands. "From very early days we saw it, I guess from two different directions, one was either to see a challenge or a problem that we have got in industrial automation and then say can we see a phenomenon in nature that could give us some clues on how to solve it. Or the flip side would be is there something in nature that inspires us and that we can then study and see if there is an application within industrial automation."

The resulting programme has gone under the name of the Bionic Learning Network since 2006 and has produced some eye-catching products over the years. This year's batch, revealed at the Hannover Fair in April, included BionicAnts, eMotionButterflies and the FlexShapeGripper, more of which later. Previous projects included birds, fish, penguins, jellyfish, arms and many more.

It is not intended initially as a product demonstrator for the company, although that does come further down the line. Initially it is a case of picking a phenomenon, like the movement of a fish tail or a birds wing, and then try to understand it to the point where it can be modelled, simulated and then translated into the world of CAD.

"In parallel we are seeking to try and apply the technology," said Sands. "We are looking to see where the applications are in industrial automation but also along the line somewhere we will try and build a model, based wherever possible back on the original natural phenomena that we observed in the first instance, that tries to demonstrate some of the technology that we have been inspired by." This year's BionicANTs, for example, which are designed to demonstrate collective and flexible working, are still very clearly ants.

"The concepts that we build and normally release at Hanover Fair every year are really the demonstration of some of the technologies that we have been working on in the background, either directly ourselves or, it is important to say, through a network of universities and other like-minded companies that we are working with," added Sands. Indeed, one of the reasons for the concepts is to create awareness of the technologies and therefore encourage more collaboration partners to engage in open research.

Annual releases

In general the plan is to work on a number of projects, with some running for several years, and be able to unveil new ones at the Hannover Fair every year, but many are long term and can re-visited if the original technology can be taken in different directions. For example the elephant's trunk was the inspiration behind the Bionic Handling-Assistant launched in 2010 - a lightweight, dexterous handling system. Two years later it was integrated with vision systems to get feedback through the system as well, and now it is being used as the basis for some voice control technology that the company is working on.

Voice control has consequently only recently become an area of expertise for Festo, but that, according to Sands, is one of the attractions of the programme: "Different methods of human machine interfacing very much are Festo's areas of expertise. We have done everything from thought control of machine interfaces to various haptic feedback devices and now to voice control as well. So, if you think about the big issues that we are looking at in terms of sensing controls, lightweight structures, safer environment, energy efficiency, these sorts of big major trends that we will be looking at, it is relatively easy to dive into nature and see examples of things that you would like to emulate in engineering terms.Some are more challenging than others obviously."

Concepts will not make their Hannover debut until the natural phenomenon is understood and the demonstrator is in good enough state to demonstrate that. Such products are produced by a team in Stuttgart which, apart from the expected engineering expertise, also includes a doctor from the biological side who looks at and co-ordinates research done elsewhere. This includes interaction – either 'importing or exporting' research challenges - with a number of universities including Stuttgart and Delft.

What external expertise is needed depends on the project. Festo's wide engineering capability covered such things as the 3D modelling and 3D printing on the elephant's trunk, but they were also working with the Fraunhofer on the modelling of the expansion joints. Sands said: "It is like a flexible bellow structure and some of their people were getting involved in developing the shapes of those bellows and the thicknesses of the materials to give us the flexibility that we wanted."

Blue sky to reality

One of the recent introductions, the FlexShapeGripper was another that needed development work on the materials. This concept actually came out of the previous fishtail as the same technique could be used to flexibly wrap round different shapes. In its initial form parts were 3D printed but when it became clear that this was a technology that had a definite application, the manufacturing method needed to be adapted.

The application was the food industry but this would only be possible if FDA (the US Food and Drug Administration) approved materials were used. Materials with the required approvals and properties were not available for 3D printing and so other manufacturing methods were required – a moulding process – that would not typically have been looked at until a concept was reaching the point of higher volume commercial adoption.

To date the Adapted Gripper is the only concept that has turned into a standard commercially available product. "A lot of the other things weren't really designed to be product in their own right, they are technologies," said Sands. "So things like the energy recovery in the bionic kangaroo, and the ability to store energy within a cycle of an industrial automated machine, that's very much something that we are interested in and will be incorporating into future products."

The Bionic Kangaroo came out of the blue sky side. The head of the bionics team was fascinated by some of the statistics he was seeing on kangaroos, that they are more energy efficient and they can travel further and faster than the pure calculations on the amount of energy it takes to do each jump. As a consequence Festo got involved in research that looked at how kangaroos have especially developed hamstrings that are a bit like rubber bands - when they land they store up the energy for the next spring going forwards. Sands added: "His mind was going with the parallels to a lot of industrial automation movements that we get involved with in the making energy recovery storage and then re-use it again. So he set his team the challenge of trying to understand this in more detail and then the quite considerable challenge of trying to build a model to demonstrate it.I say it's tricky because when they were first developing it, it was the balance that they struggled with - in take-off and re-adjusting balance in mid air and landing correctly to be ready to store that energy to get the feet and the legs in the right attitude to store the energy to then do the next spring coming off from it."

The Bionic Kangaroo was launched in 2014 and by the time it had made a guest appearance at the company's UK HQ had been fitted with gesture control as the form of human machine interface.

BionicAnts colonise 2015

Star of the show this year has been the BionicAnts which has looked not just at the individual ant but also its role in cooperative working. Like their natural role models, the BionicANTs work together under clear rules. They communicate with each other and coordinate both their actions and movements. Each ant makes its decisions autonomously, but in doing so is always subordinate to the common objective and thereby plays its part towards solving the task in hand.

This cooperative behaviour provides interesting approaches for the factory of tomorrow. Future production systems will be founded on intelligent components, which adjust themselves flexibly to different production scenarios and thus take on tasks from a higher control level. The BionicANTs demonstrate how individual units can react independently to different situations, coordinate with each other and act as an overall networked system. By pushing and pulling together, the artificial ants move an object across a defined area. Thanks to this intelligent division of work, they are able to efficiently transport loads that a single ant could not move.

The design of the ants is interesting. Laser-sintered components are subsequently embellished with visible conductor structures in the 3D MID (moulded interconnect device) process. The electrical circuits are attached on the surface of the components, which thereby take on design and electrical functions at the same time. In this way, all the technical components can be fitted into or on the ant's body and be exactly coordinated with each other. After being put into operation, an external control system is no longer required. It is possible, however, to monitor all the parameters wirelessly and to make a regulating intervention.

The BionicANTs also come very close to their natural role model in terms of design and constructional layout. Even the mouth instrument used for gripping objects is replicated in very accurate detail. The pincer movement is provided by two piezo-ceramic bending transducers, which are built into the jaw as actuators. If a voltage is applied to the tiny plates, they deflect and pass on the direction of movement mechanically to the gripping jaws.

With two rechargeable batteries on board, the ants can work for 40 minutes before they have to link up with a charging station via their feelers. All actions are based on a distributed set of rules, which have been worked out in advance using mathematical modelling and simulations and are stored on every ant. The control strategy provides for a multi-agent system in which the participants are not hierarchically ordered. Instead, all the BionicANTs contribute to the process of finding a solution together by means of distributed intelligence. The information exchange between the ants required for this takes place via the radio module located in the torso.

The result could have an impact on production facilities in the future. If more products are customised then the automated production environment will need to be able to adjust accordingly – increased flexibility without increased manpower. BionicAnt technology could be a step towards such environments.

Natural technology

But is Festo doing anything new through its Bionic Learning Network, or is it pulling together other people's technology? Sands responded: "It is a really interesting question. A lot of people for many years, since Leonardo, have been trying to create a machine that flies and can do it in the same way that a bird does rather than just gliding or just through sheer power as in a jet aircraft, and we can show understanding and the ability of flight shown in the SmartBird and the BionicOptor, which is a flying dragonfly. What Festo could bring was the knowledge that we have got in-house of the way the air moves, flows and the effects of that, and then combining that with a close look at nature. I think that is how we have managed to solve that, where for many years people haven't been able to."