π
2023-06-16 01:01
in Arduino, Clubbing, Electronics
This is the untethered update to my v5 outfit. Please see LED Pants and Shirt v5 on ESP32 and Raspberry Pi with P2 RGBPanels and Wifi for how the entire setup works, and for the new LED strips on arma and legs, you can see Party LED Outfit Version 5.5: Flexible P15 LED Strings, LED Fanny Pack, Rez Inspired LED Goggles, LED Laces and LED Shoes
And if you want even more details and history >>> See this full article on the why and evolution of my LED outfit <<<
For all these years, my outfit has relied on a fanny pack filled with batteries, and with an unslightly tether from the fanny pack to the panels, bringing 2 feeds with 5V (as backup and to spread out the amps over 2 wires). That system worked for many years and would survive the failure of one of the 2 5V connections, or even the 16V connection meant to feed the rPi from its own power source stepped down to 5V on the panels (so that it doesn't see a voltage dip on the remote 5V rail when the display sare fairly bright).
All in all, it worked, but the fanny pack tether and wires were cumbersome, and some security folks didn't like all the wires.
After switching to a new neopixel controller that is directly USB powered, it made more sense to power the panels locally and put the batteries on the panels:
For comparison, the old panel on the left only has the rPi and a small 16B to 5V converter and than relies on that tether cable to the white box on the left which has the DC-DC step down and the ESP32:
finished design with padding, power routing from 3 lipos or 2 USB attery packs
The new version works like the old one, but with batteries directly attached to the panels, which in turn makes them much heavier, but oh well. Video with Lipos and DC-DC converter:
However, the more interesting upside is that I could also replace the 16V lips that get stepped down to 5V, with 5V USB Battery packs. the reason I never did that at the time is that the entire system takes way more than the maybe 2.5A you can get from USB packs on a good day. A somewhat cumbersome workaround to this problem is to use 2 USB battery packs with 2 independent outpus each, meaning 4 independent 5V busses able to put out up to 2.5A depending on the battery pack. So, I split my power system in 4:
front LED panels (3 panels) (1A or more depending on pattern)
rPi (about 1A depnding on CPU load, but must be a nice consistent 5V or the rPi will complain)
Neopixel string run by the ESP32 output if desired. This one might brown out but can be put on a separate USB pack to avoid taking other things down with it
Rear LED panels (also about 1A).
In total it means the whole thing uses about 3A at 5V, or 15W, which means 180Wh for 12h. In theory 2x 99Wh battery packs would work for 10H, but in real life, the first battery pack gets a lot more load since it runs the rPi, so it only really lasts about 7H before I have to replace it. Not ideal, but still nice that I can run from USB instead of lipos if needed:
