Persistence of Vision Fidget Spinner

Last year I was at the Embedded World fair in Nurnberg, Germany. There was a Microchip's booth where they, among many things, presented their new peripheral in PIC16 series MCUs, called Angular Timer. As a demo of this new feature they developed a fidget spinner which they were giving away:

This is the moment I got an idea to do one by myself. Of course, I didn't want my project to be the same as theirs so I was looking for ways how to improve the Microchip's fidget spinner. 

At the end I came up with fidget spinner which is nothing like the Microchip's, except for the MCU (because of the AT) and the BLE module (it was the smallest BLE module I could find on the market at the time). My fidget spinner has:

- Improved resolution (32 LEDs instead of 8)

- Two colors of LEDs

- Much better efficiency in terms of battery usage which leads to longer battery life

- Capacitive touch button for turning on and changing between the different modes

- Uses only one magnet and omnipolar hall sensor instead of two magnets and bipolar sensor which reduces costs and assembly time

You can read more about Microchip's fidget spinner here: https://www.microchip.com/promo/bluetooth-fidget-spinner

This project was presented at Electrotechnical and Computer Science Conference ERK 2018 in Portoroz, Slovenia. The conference was organised by IEEE Slovenia. 

You can read the publication at: https://erk.fe.uni-lj.si/2018/papers/nogic(programirljiva_prstna).pdf Although the paper is in Slovenian (apart from the English abstract), there are some images that are not posted here.

This is how the design started:

In the last log you can see how it looked like at the end. This PCB was specific because of its shape so a lot of traces needed to be curved by some angle. Luckily, Altium has this worked out very well.

The PCB is dual layer. Images of the layer are shown bellow. Gerbers are available at the Files section.