Rudelblinken === Build your own blinking cat ears and make the IoC (Internet of Cats) a reality. **Where?** HASS (Hall 3) **When?** 28.12.2024 from 11:30 - [GitHub repository](https://github.com/zebreus/rudelblinken)  ## Materials & Tools All materials are provided. Material cost is around 5€, however if you want to support the project a voluntary donation of 10€ would be nice. In case you don't want to/can't spend money just ask zebreus nicely and you'll get the materials free of charge. - Cat ears - [Rudelblinken PCB](https://github.com/zebreus/rudelblinken/tree/main/board) - LED Strip - Soldering iron - Clippers - Hot glue ## Instructions These instructions are not perfect. You can edit/improve them in this editor. 1. Remove the excess taps from the pcb with a pair of pliers  2. Cut the LED strip to match the length to the cat ears. Make one cut right at the soldering pads of the LED strips (see red arrow)  3. Remove a part (~1cm) of the transparent plastic film on the side of the LED strip to reveal the soldering pads. Note the polarity of the LED strip.  4. Make sure you actually removed the transparent double sided adhesive and not just the protective film. 4. Add solder to the two relevant soldering pads on the PCB. The relevant pads are the one in the middle and the left one on the picture. (marked with a + on the PCB)  5. Also add solder to both pads on the LED strip. Again, make sure, you are working on the correct end of the strip (the polarity should be the same as in the picture).  6. Use a helping hand to hold PCB and LED strip in place. Use an additional alligator clip to perfectly align the LED strip with the PCB.  7. Solder the PCB and LED strip together at 350°C. Hold your soldering iron onto the first pad and wait until it melts. Then keep it on the pad for another 5 seconds. Repeat that for the second pad. Your LED strip should be a bit closer ro the board than before. 8. Repeat the previous step to make sure the connections are fine.  8. Your consturuction should now look like this  9. On the provided cat ears also remove a part of the plastic with the pliers to make the PCB fit.  10. Remove the transparent plastic film from the back of the LED strip and stick the LED strip to the cat ears. Use Sekundenkleber to stick the PCB to the cat ears. 11. That's it. meow :3 ## Q&A **Q: How are the cat ears synchronized?** A: Rudelblinken uses [ESP-NOW](https://www.espressif.com/en/solutions/low-power-solutions/esp-now) over WiFi to signal when they are blinking. All other cat ears receive these signals and [adjust their frequency and phase](https://github.com/zebreus/rudelblinken/blob/main/sync.toit) towards the average of all other cat ears in proximity of the sensor. This resembles a self-regulating system which works without a central instrance which controls the other devices :3 **Q: Can I build my own from scratch?** A: Theoretically, yes! The PCB design & the firmware are all available in the [Rudelblinken Repository](https://github.com/zebreus/rudelblinken). However you would have to get the PCB printed and assembled which is rather expensive for low quantities.