While textiles, clothing and textile-based soft materials have not traditionally been a focus in robotics, researchers in the United States especially are increasingly combining the two to perform certain functions, such as helping robots to ‘touch’ and ‘feel’ their environment.
“It [making soft and flexible components] is one of the last spaces that, not just robotics, but electronics in general have had difficulty working into,” said Adam Whiton of the Massachusetts Institute of Technology's (MIT) group developing socially engaging robots for everyday life.
Robotics can perform certain functions with textiles incorporated into their materials, rather than with rigid components; for example, in robots that can squeeze into small spaces, which always interest the US military, said Mr Whiton.
Likewise, Boston Dynamics, a US engineering company, has designed a Protection Ensemble Test Mannequin (PETMAN), an anthropomorphic robot that walks freely and performs various movements to test clothing designed to protect soldiers from chemical warfare agents, noted a spokesperson for the USA’s Defence Advanced Research Projects Agency. Testers can even control PETMAN's temperature, humidity and 'sweating' to simulate a soldier's physiology to study the stress of human movements on the textiles, according to Boston Dynamics.
Textiles can also be used to improve interactions between robots and people: “Our perspective is we want to interact with them kind of like the way we do with people,” said Mr Whiton.
This does not necessarily mean humanoid robots, but robots that can understand communication through touch; for example, one MIT project involved covering a robot in a textile of quantum tunnelling composite (QTC), an electrically conductive material made up of particulates of metal and metal oxides which, only when placed under pressure, becomes a conductor. This is used to create touchable sensor and switch systems in robots as well as textiles. The project aims to make the robot understand, for example, that a pat on the back is a commendation. The sensing textile, which covered the entire body of the robot, was easy to use and removable: “Kind of like putting on a suit,” said Mr Whiton.
Textile surfaces could also make a robot more personalised to an individual with whom it is interacting; Mr Whiton said his research involves developing a thermochromic textile worn by a robot, which can change its colour and match what a person was wearing.
Meanwhile, Yorkshire, UK-based Peratech is currently working with the UK Centre for Process Innovation on printing its patented QTC material in an ink formulation onto surfaces including textiles, said David Lussey, Peratech's chief technology officer. This ink contains can be silk-screen printed on various surfaces and entire circuits could be printed out. This means a variety of electronic functions can be packed into small, flexible substrates – a potential benefit to robotics developers seeking flexible, functioning electronic parts. “Textiles are important...Giving them other forms and functions is becoming one of the things that a lot of people want to do,” said Mr Lussey.
Over in California, independent specialist Ian Danforth, who works in robotics and machine learning, is working with Berlin-based electronics developer Hannah Perner-Wilson on the design of rSkin, an open-source sensor 'skin' for robotic limbs of any shape that detects the and location and intensity of pressure applied to its surface. It allows for “machine learning and robots being able to interact with their environment and discover both properties of their own motion,” he said. He added touch sensitivity has been largely ignored this far because of cost.
rSkin consists of a neoprene base fabric that provides the resilient, "fleshy" backing of the skin, a piece of resistive fabric, a stretchy knit fabric, and a conductive material made of silver-coated conductive thread, said Mr Danforth.
The way that electronics are being integrated into textiles is also being undertaken in a way that makes a textile product robotic. Researchers at the USA’s University of Colorado, Boulder's Correll Lab have designed a dress embedded with a network of microphones to detect sound and notify the wearer of its direction using vibrating winglets. The design for this ‘Flutter’ robot - so-called because the winglets appear to flutter when they vibrate - was inspired by people with hearing impairments and won ‘best in show’ and ‘best in most inclusive and usable design’ awards at the International Symposium on Wearable Computers exhibition last year, staged in Newcastle, north-east England, said Halley Profita, the designer.
“It doesn't look like a form of assistive technology, which is what people like,” said Ms Profita, adding Flutter could help people with hearing impairments locate and react to sounds around them.
The garment, made of poly cotton with a cotton-based material for the winglets, contains six tiny microphones connected to micro-controllers, which communicate with each other to determine the direction of a sound and then activate vibration motors, orienting the winglets in that direction.
Flutter is portable, with no need for an external computer. “We can make it into any shape that we want,” said Prof Nikolaus Correll, who also worked on Flutter.
Ms Profita said she plans to test Flutter vests later this year, giving them to individuals with hearing impairments to use. In the future, Flutter could be washable, able to vibrate in different ways to indicate the intensity of sound, or be used to augment, for example, hearing aids, which have trouble distinguishing the direction of sounds.
Japan is another major robotics research centre and here developers are just starting to assess the potential interactions between robots and textiles. Professor Ken Nakamura, a scientist with the Kibo Robot Project, which is trying to improve human-robot communication, said his colleagues are designing a red, white and black humanoid robot that will converse with robots stationed aboard the International Space Station. The idea is that it can essentially relay messages to human astronauts from the more mechanical robots and “help solve social problems through communication.” They have not yet considered its clothes, said Professor Nakamura, “But I guess it's something we will have to do in the future.”
It is a similar story at robot developers Kokoro Co, where humanoid robots are made for the entertainment industry. “They are pretty much the same clothes that humans wear, although we do alter them with cuts and the addition of lots of zips to make them easier to put on the robots,” said Kasumi Futakami, of the sales department.