According to N + 1, the speaker prototype emits ultrasonic signals inaudible to the human ear. Then the column catches the reflected signal and from it determines the small displacements of the skin that occur during heartbeats.

There were difficulties in the development. The fact is that extraneous noises were also recorded. Then the engineers installed an array of several microphones. The algorithm combines signals from them to find patterns of heartbeat.

The column has already been tested on volunteers. These devices were compared with ECG data. It turned out that the column determines the heart rate quite accurately. The correlation coefficient was 0,929.

In the future, such speakers may help people monitor their health.