Massachusetts Institute of Technology (MIT) engineers have developed a new category of wireless wearable skin-like sensors for health monitoring. This new sensor called ‘e-skin’ is an ultrathin semiconductor film made of a piezoelectric substance that adheres to the skin, sensing the vibrations of the body. Moreover, the sensor does not require any power source. This development by MIT engineers is a distinct type of wearable sensor that is able to send signals related to pulse, sweat, and ultraviolet exposure, without using bulky chips or batteries.
The heart of this sensor is an ultrathin film of gallium nitride, a material that can both produce an electrical signal in response to mechanical strain and mechanically vibrate in response to an electrical impulse. The piezoelectric material can generate an electric signal when mechanical strain is applied and will vibrate when electricity is passed through it. It can therefore sense as well as transmit signals wirelessly.
In addition, activity levels are smoothly sent from the sensor to the smartphone for further analysis and interpretation of the findings. This innovation paves the way for chip-free wireless sensors.