What do you think about when you picture a robot? A shining metal man? A factory production line machine? Maybe you picture a remote-controlled cleaning device, a self-driving car, or even a security bot?
These are all traditional, hard robots – inflexible constructions which are limited in their application, partly due to the safety problems they pose to human beings. However, a new field of robotics is emerging which takes these issues into account, offering countless potential applications from medicine and surgery to machine repair. This is soft robotics.
The field of soft robotics concerns the creation of robots constructed of compliant materials and flexible links rather than the familiar rigid-bodied robots made of metals, ceramics and hard plastics. Now, researchers at the Eindhoven University of Technology (TU/e) are exploring the multiple potentialities of soft robotics, including artificial hearts and micro-bots to perform surgery and dispense medicines. The team of researchers is led by Bas Overvelde, associate professor within the Soft Robotics Group (part of the Mechanical Engineering faculty) and scientific group leader of the Soft Robotic Matter Group at AMOLF. In 2020, Overvelde received a five-year ERC start-up grant of more than €1.5 million to increase the application perspective of soft robots. The project brings together researchers from different disciplines and faculties at TU/e, such as Chemical Engineering and Chemistry, Industrial Design and Mechanical Engineering.
“Scientifically, it’s an incubator for new directions and research,” Overvelde said. “It’s a great topic that brings researchers together, which continually generates new ideas. Such an interdisciplinary approach is characteristic of a new science with which we are pioneering in all kinds of areas: materials, mechanical intelligence, interaction with humans, design. Precisely because it requires a very different way of thinking that goes more towards the intelligence of nature. It’s a form of artificial intelligence.”
A key feature of soft robotics compared to hard robotics is its autonomous adaptability. The complex shapes and deformable bodies made possible with soft robots bring their own challenges, as they are less predictable and require new design methods to get them to perform desired functions. Traditional robots have hinge points, hard moving parts and interfaces, which makes them suitable for repetitive actions and programmable sequences.
Jaap Den Toonder, leader of research section Microsystems, explains: “Soft robots respond to stimuli such as air pressure or light. Their movements result from the reaction and deformation of the material, which is where the intelligence lies. That leaves a lot of room for complex possibilities. That’s why a whole chain of research disciplines is needed: to devise and develop the right materials (chemistry), to make the mechanical design and to direct and control the systems (mechanical engineering).”
The softness and flexibility of soft robots makes them ideal for human interaction, as Overvelde points out: “A soft robot will never squeeze your hand. The power of hard robotics makes collaboration between humans and robots more difficult, so soft robotics is a way to make that interaction safer. In the slipstream, that also helps social acceptance, because soft robots are closer to us. What is more likely to be accepted in our bodies; a hard pump or a beating object that resembles a natural heart? Such questions must ultimately be tested.”
Miguel Burns of the Faculty of Industrial Design agrees. He says: “Soft materials fit humans better than hard, mechanical ones. But what makes it especially innovative are the dynamic properties that the use of new materials entails. This makes it possible to manipulate physical properties in a controlled way and adapt them to the needs of the user, such as humans. Although animals, plants or buildings can also be users for that matter. That adaptive nature is the interesting thing about soft robotics.”
Another useful application for soft robotics is in the field of haptics, which concerns perception through the hands. This is the field of researcher Irene Kuling of research section Dynamics and Control. She says: “We are currently using soft robotics in two ways: the development of a hand that imitates human movements as lifelike as possible, and the development of objects with which we can provide haptic feedback to people from a distance. In other words: feeling without being present. Think, for example, of maintenance in a nuclear power plant, giving a hand via video calling, or digitally touching curtains before ordering them online.
“A lot has already happened in that area, such as 3D images, sharper pixels or surround sound, but in terms of sensing, very little exists. Soft robotics is changing that and we are just at the beginning. With traditional robotics we think very much in performance terms, whereas with soft robotics we can be much more creative. Who knows, it might lead to a real life Barbapapa, something that can turn into both light and heavy objects.”
The possible applications of soft robotics are wide-ranging, but naturally limited. However, as researcher Danqing Liu from the Faculty of Chemical Engineering and Chemistry points out, the limitations themselves present even further opportunities: “Since soft robotics lacks the power of hard robotics, we need to turn the differences into an advantage. Such as the combination of moving surfaces with dynamic coatings, which allows us to use vibration to clean hard-to-reach objects without water. For example, solar panels, or think of the Mars Rover, which has to deal with sandstorms. NASA has already encouraged us several times to work out this principle further to meet the extreme conditions in space.
“Also in the field of haptics, with coatings on screens that allow you to feel what is happening in another place. That’s valuable for blind people, or for surgeons to experience what’s happening in the body. Another application is a control panel in cars that allows you to regulate functions without looking, so that you continue to pay attention on the road. Soon we’ll actually be able to do two things at once. If we apply this form of touch sensation feedback on a large scale, it will have a huge impact on the human machine interface. We’re going to change the world.”
One of the questions addressed by researchers is how to bring intelligence to the point where soft robots react autonomously, for example to their environment or to chemical substances. Among other applications, this would enable soft robots to perform surgery and repairs, Den Toonder points out: “Ultimately, we want to make robots on a microscopic scale, smaller than a hair’s breadth, that walk through the body and deliver drugs locally or do surgery. Or that perform repairs in complex machines with very small parts.”
The possible applications don’t stop there. Edible robots could be created which are capable of changing shape to deliver drugs or nutrients at a specific location. Plant-based foods could simulate meat, such as 3D printed algae-based hydrogel ‘bacon’ which reacts like the real thing when cooked.
So what, then, is a robot? Will we one day get to the stage where, as Isaac Asimov says in I, Robot, ‘You just can’t differentiate between a robot and the very best of humans’, or will there always be a clear and discernible difference between robot and human; between the organic and inorganic? One thing is certain: our concept of what a robot is will need to be as flexible as the new generation of robots themselves.
Source: https://www.tue.nl/en/news-and-events/news-overview/01-06-2022-collaborating-on-a-real-life-barbapapa/