Small form BLE + Accelerometer Moderators: adafruit_support_bill, adafruit

[jdioffers]

Hi -
I'm looking for a *small* board that has bluetooth, accelerometer, a little flash memory and can be operated using a coin cell*.

My goal is to build a shoe-mounted (perhaps clipped on the laces?) BLE Pedometer with an accompanying app so that the sensor can be accessed via phone. I'm accomplished at Arduino, C, app building and feel confident in my abilities such as they are.

The high-level board requirements are as follows:
- BLE so that the phone can pull data from the sensor to populate the app
- Accelerometer with Tap and Double Tap
- Coin cell holder (*or... perhaps a lipo with Qi charging abilities would be cool(er) [note: BLE won't be on all the time]
- Some flash memory. At least 1MB would be great (and more would be better :)

So far I've found these examples online:
- AliExpress (example: https://www.aliexpress.com/item/32859423925.html)
- MIT Media Lab prototype (https://sensorsnaps.media.mit.edu)

Note: I've never designed or built my own board but am starting to wonder if I need to go that way. Ideally there one of you guru's can point me towards something that would work which is Arduino compatible. Also - I'm willing to drift away from Arduino if necessary and the tool-chain isn't too egregious.

thank you!
--J

[oesterle]

Hi, jdioffers!

I'd try the Adafruit Feather nRF52840 Sense for your first prototype.

It has built-in charging for LiPo/LiIon cells. Adafruit has a number LiIon & LiPoly of various sizes that will work right out of the box.

The Sense also has a built-in 9-DOF IMU, including an accelerometer, gyro, and magnetometer; also, a BME280 pressure sensor/altimeter, so you can track those uphill runs and stair climbs.

There's a lot packed into this small board, and it's programmable in CircuitPython or Arduino. You'll find detail in the primary guide: Adafruit Feather nRF52840 Sense.

Looking forward to seeing your progress!

Cheers,

Eric

[jdioffers]

Hi Eric!
Thanks for the fast reply. Yes, those boards would be good for prototyping indeed - you are right. But I'm looking for the final form factor which is quite small.
The Serpente (for example) is about as 'big' as I would want to go (https://www.adafruit.com/product/4513).

--J