This Arduino project lets you see your heartbeat
It’s easy enough to check your heart rate, but Sharath Naik has designed a project that actually lets you see it instead. The roughly heart-shaped, 3D-printed device sits on a pedestal with four sections that are pushed out in response to your pulse.
The visualizer utilizes a servo and linkage system to physically actuate beating, and a MAX30100 pulse oximeter mounted to the base is implemented to track your heartbeat. This data is fed into an Arduino Nano board, which signals the SG90 servo to expand and contract the model in response to your own body.
More info and code are available in Naik’s post, and you can see it in action below!