Graphene-treated rubber bands used as inexpensive body motion sensors
By Ben Coxworth
August 20, 2014
Graphene is a cutting-edge wonder material, used in applications ranging from solar cells to supercapacitors. Rubber bands, on the other hand ... well, they're not so high-tech. By combining the one with the other, however, scientists have created ultra-cheap body motion sensors that could make a big difference in the field of health care.
The researchers, from the University of Surrey and Trinity College Dublin, have infused regular rubber bands with graphene. The treated bands remain stretchy, but thanks to the graphene, they're also electrically conductive. If they're wired up to a power source and then stretched – as the result of even a subtle movement – there's a very detectable effect on the current flowing through them.
They're reportedly capable of sensing the motions associated with functions such as breathing, pulse and joint movement. This means that they could be used to alert caregivers if there was a change in a patient's respiration or heart rate, or if they ceased moving for too long.
Along with their use as stand-alone sensors, it has been suggested that they could be incorporated into lightweight sensor suits, which would be worn by vulnerable patients such as premature babies. They could also conceivably find use in fields other than medicine, being incorporated into automotive airbag-triggering systems, robots, or performance-assessing athletic clothing.
Versatility aside, however, their low cost is still one of their biggest selling points.
"These sensors are extraordinarily cheap compared to existing technologies," said the study leader, Trinity College Dublin's Prof. Jonathan Coleman. "Each device would probably cost pennies instead of pounds, making it ideal technology for use in developing countries where there are not enough medically trained staff to effectively monitor and treat patients quickly."
A paper on the research was recently published in the journal ACS Nano.