A stretchable sensor can lead to new types of wearables with health and fitness applications
The scientists used carbon nanofiber powder and hydrogel to create the sensor. By combining the excellent conductive properties of the carbon powder with the elasticity of the hydrogel, they were able to produce a material that can be stretched more than 3 times its length (366%) and compressed by up to 70%. The carbon nanofiber powder also contributed to the mechanical strength of the sensor, while the biodegradable hydrogel allowed it to keep its flexible properties.
Having a material that can stretch and flex and still be highly conductive is a perfect platform for developing a wide variety of wearable electronics. Placed on the skin at different spots on a human body, the sensor can register strain and pressure, thus performing different measurements. It can detect swallowing when it’s on a person’s throat, bending of the knees or elbows, finger movements, and breathing. The sensor can also accurately register touches and presses even when stretched by 100%.
What’s even more encouraging is that the whole process of creating the hydrogel-carbon sensor is easily scalable, which in practice means that the sensor will be cheap to mass-produce. It has a wide array of potential applications - from tracking athlete performance to helping people with medical conditions keep an eye on their stats. Integrating the strain sensor into current wearables won’t be an easy feat, though. Nevertheless, it could find its place in highly specialized medical and professional athlete devices.