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Wearable BP Cuff During Exercise

complete

A blood pressure cuff you can wear through a workout, which takes its own reading when it notices your arm has gone still.

Blood pressure during exercise is a real blind spot. People experience hypertensive and hypotensive episodes mid-workout, and there is no good way to catch it — current equipment needs you in a clinic, which is not ideal for being able to relay that information to your doctors as these episodes happen.

The board.
The board.

So the device waits for its moment. You work out; you stop for a few seconds; the Nordic Thingy on the strap reads its accelerometer and decides your arm is at rest. That is the cue. It drives the valve, inflates the cuff, takes the measurement, and sends it over Bluetooth to a phone app — no button, no interruption, nothing for the wearer to remember to do.

Bench setup — the development kit wired out to a breadboard.
Bench setup — the development kit wired out to a breadboard.
The cuff inflating on cue. Watch on YouTube
Worn: sash across the chest, module at the shoulder, cuff on the upper arm.
Worn: sash across the chest, module at the shoulder, cuff on the upper arm.
The wearable, on a person, in the lab.
The wearable, on a person, in the lab.

I designed the PCB and wrote all of the firmware — bringing up the valve, the pressure sensor and the Bluetooth connection, on the nRF52833 with Zephyr. There is a KiCad project alongside the firmware for the board itself.

Built with Jackie Herzberg, Kyle Duerr and Grant Breit.