Berkeley, California – Polyurethane makes a 3D printed ‘earable’ smart device possible. The device, created by researchers at the University of California, Berkeley, enables body temperature to be detected and monitored in real time.
Fluctuations in body temperature can signal health conditions ranging from infections to insomnia to depression. Current wearable sensors can detect the temperature on the skin, but this is prone to environmental effects. By using a device designed to be worn in the ear, this is avoided.
To make the devices, first an insert designed to fit an individual’s ear shape and ear canal size is 3D printed using a stretchable polyurethane filament. This contains microchannels into which chips and liquid metal connectors can be inserted, before sealing with PMDS and epoxy resin. A Bluetooth module is also included to allow data to be sent to a smartphone app, and a microphone to capture and transmit outside sounds to the inner ear so that hearing is unaffected.
Once calibrated, the temperature measurements the sensor creates closely matched those made using a commercial ear thermometer. The researchers speculate that it might also be possible to incorporate EEG into the device to expand its health monitoring potential.
Reference: H. Ota et al. ACS Sensors 2017, 2, 990