With millions of people currently sporting fitness trackers on their wrists, wireless and wearable sensors are all the rage. Footsteps can be counted and heart rate and other important vital signs can be monitored using these devices. In the journal ACS Sensors , it has been reported that the Researchers have developed a 3D-printed sensor that can be worn on the ear. This sensor measures the core body temperature, which is one of the most fundamental medical indicators of health in real time.
An "earable" sensor can track core body temperature -- a key health indicator -- continuously. Credit: American Chemical Society
A range of health conditions can be detected through the ups and downs of core body temperature. The most common is an infection, which causes a fever. But temperature changes can also be a sign of depression, metabolic function, fatigue and insomnia. Present wearable sensors can sense skin temperature, but this can change based on how cold or hot an environment is.
Oral and other thermometers that measure core body temperature are specifically developed only for a period of time and are not meant to be strapped on for constant detection. Hence, to monitor core body temperature in real time on a continuous basis, Ali Javey and colleagues set out to develop a convenient device.
A 3D-printed device was fitted with data processing circuits, a wireless module and an infrared sensor, which detects ear (and thus core body) temperature. The ear is covered by a disk-like structure which can be specialized to fit the contours of a person's ear for a convenient fit.
The Researchers fixed a microphone to capture and transmit outside sounds to the inner ear in order to make sure that users can still hear clearly while wearing the device. And, temperature measurements are transmitted to a custom smartphone app through the Bluetooth module. Testing revealed that the "earable" sensor measurements were very much similar to those of a commercial ear thermometer.