Most attempts at giving robots muscles tend to be heavy, slow or both. Scientists might finally have a solution that's both light and nimble, though. They've developed fibers that can serve as artificial muscles for robots while remaining light, responsive and powerful. They bonded two polymers with very different thermal expansion rates (a cyclic copolymer elastomer and a thermoplastic polyethylene) that reacts with a strong pulling force when subjected to even slight changes in heat. They're so strong that just one fiber can lift up to 650 times its weight, and response times can be measured in milliseconds.
As the geriatric population is expected to balloon in the coming decade, so too will rates of heart disease in the United States. The demand for prosthetic heart valves and other cardiac devices -- a market that is valued at more than $5 billion dollars today -- is predicted to rise by almost 13 percent in the next six years. Prosthetic valves are designed to mimic a real, healthy heart valve in helping to circulate blood through the body. However, many of them have issues such as leakage around the valve, and engineers working to improve these designs must test them repeatedly, first in simple benchtop simulators, then in animal subjects, before reaching human trials -- an arduous and expensive process. Now engineers at MIT and elsewhere have developed a bionic "heart" that offers a more realistic model for testing out artificial valves and other cardiac devices.
Researchers in Switzerland have found a new way to make highly elastic fibers that can be embedded with sensing components to double as nerves in a robotic nervous system. The fibers, developed by scientists at the École Polytechnique Fédérale de Lausanne (EPFL), are built from elastomer, which make them extremely flexible. When combined with electrodes, the fibers become sophisticated sensors that can detect pressure and strain. The flexibility makes these sensors ideally suited for a number of non-traditional robot forms, including soft robots that mimic biological organisms. The process used to make the elastic fibers is identical to the thermal drawing technique used to produce optical fiber.
Embroidery is usually used to adorn fabric with festive designs, but it can now be used to measure heart rates too. In a new study published in the Journal of the Royal Society Interface, researchers unveiled a fiber optic material that can be produced quickly and then woven, knit, or embroidered into existing fabrics, forming flexible, wearable sensors that seamlessly integrate into clothes. "From the side of our medical partners, that's the first thing that they ask us," says Luciano Boesel, a researcher at Swiss Federal Laboratories for Materials Science and Technology, Dübendorf (EMPA). Having clothing be washable is vitally important in a healthcare setting like a hospital or rehabilitation facility, where people are injured or sick, and susceptible to catching other diseases. This particular study is part of a larger project that Boesel and colleagues are working on, with the ultimate goal of developing sensors that can monitor health signs in paraplegic patients, who often run into problems with traditional sensors which can rub against the skin and eventually form sores.
Researchers have been trying to build durable, low-cost synthetic muscles for years but to no avail. The systems developed so far have either been too expensive to produce en mass (like carbon nanotube) or too delicate and power hungry (looking at you, shape-memory alloys) to be useful outside of laboratory conditions. But a team from MIT have just struck upon the Goldilocks zone of robo-muscles with nylon fiber of all things. The secret, according to a report published Wednesday to the journal Advanced Materials, lies in how the fibers are shaped and heated. See, nylon fibers have this weird natural property that, when you heat them, they contract in length but expand in diameter.