Happy (belated) Halloween! New around here, but I haven’t seen many wearable projects here yet!
This year I wanted to do something LED focused for my costume. My end goal was to make something I could easily re-use for festival season next year. The vision I started out chasing was a wizard whose body glows colored light. My vision changed a bit as the project went along, but I’m pretty thrilled with my results! Sorry for the sorta crappy video, it’s much harder than I thought to photograph these strips! Anyway, allow me to present…
I used 576 ws2812b - 4 full strips of 144/m. One strip per sleeve, 2 in the robe’s lapels/hood. The lapels and hood are reinforced inside of the hem with plastic hanging strap to force the lights away from my body and allow some light to shine. The strips are in ip67 housings, and have been wrapped in sewing tulle for diffusion and hot-melt glued to velcro strips, that way the lights can be removed and the robes can still be machine washed. The tulle/hot-melt combo is WAY more robust than I initially thought it would be, easily been through 20 hours of wear without any failures on that front! Powered from a 3A USB-C battery bank with absolutely no issues, I have easily gotten 6+hours of run time without dropping much below 50% on the bank. I am running 0.13.0-b4 on an esp8266 with a potentiometer for analog brightness control. This mod is a MUST if you’re making a wearable, I was able to attend a few concerts in my area this way without upsetting any of my fellow concert-goers! Since it’s meant to be portable, I am actually using a second esp8266 exclusively as an AP. This has made controlling it through the app possible without a home network, and is MUCH MUCH more robust than trying to access through the wled AP. I have both esp’s and the potentiometer built up in an altoids tin that sits in my pocket beneath the robes.
Overall, I am thrilled with how this came out. I have gotten lots and lots of love for this one. As an added plus, all of my terrible dance moves suddenly don’t look all that terrible once I’m dripping in LEDs
@mjg1088 Whoa, very nice! I’m actually getting a custom Playa Coat this year for Burning Man, and am going to be using WLED Sound Reactive, and I’ve been worrying myself crazy about the power. So you’re saying you’re managing 576 ws2812b with a single 3A@5v USB battery bank? Really? I’ve been thinking I’d need to use 2 battery banks with multiple 5v outputs simultaneously, or a custom 3S lipo with a buck to get 5v.
I’ve been figuring a 30/m RGBW (neutral white) SK6812, 9W/m max, figuring 50% brightness and 50% pixel LED usage, I’m estimating about 23W for 10m (estimating probably high on amount to be used) as my average, with 35-40W if I’m driving even more pixels with the music reactivity and such.
Sounds like from your experience I could get away with 1 of these batteries (well, 2 to be sure I last the full night), which seems to indicate I can get 5v@3a from USB 1 and USB 2 or 4 simultaneously. Sounds like I might not even need both ports, which would be really cool.
I’ll have to get my load tester out to see how much I can pull out of it
Hi thechnomancer, this is Miguel from México, how did you manage to power the esp8266 and the strip at the same time from the 5V 3A power bank?:
A) Did you plugged a usb to micro usb cable from the power bank to the esp8266 board and then you linked all the strips to the esp8266 for powering them straight from the board?
-B) Did you manage to obtain stable 5v and 3A from the power bank to power the esp8266 from the VIN pin and you used a second line from the same power bank directly to the led strips?
I’m stuck on a battery powered project and it seems that you found a way to have portable strips powered from a power bank!
many thanks in advance and thanks for sharing your projects.
Yep! I’m fairly sure I have the brightness limit set to match the limit of my battery bank, as I remember my battery bank going into a protection mode when I started drawing too much current from it. It doesn’t quite provide enough current to truly hit “full” brightness, but these LEDs are so bright that full brightness would be pretty unpleasant in a wearable, both for the wearer and the observers. Did you ever get this coat made? I’d love to see it!
Option B in your post. It must be done this way, as going through the on-board micro USB has a max current of ~1A, and you will likely damage the esp by exceeding that. First, I purchased a USB breakout connector like this one:
From there, I wired power directly to the V_in pin and to the LED strips. I can’t speak for all battery banks, but mine has been plenty stable to run the esp8266 without issue! Good luck out there, stoked to see what you come up with!
Thank you so much, I appreciate the information, just an additional question so I can move on and do testings, does the esp8266 was able to handle 3 amps from the usb breakout connector linked to the VIN pin?, I know the led strip can handle even 10 amps, but not sure if 3 amps is going to damage the board.
Thank you so much, I appreciate the information, just an additional question so I can move on and do testings, does the esp8266 was able to handle 3 amps from the usb breakout connector linked to the VIN pin?, I know the led strip can handle even 10 amps, but not sure if 3 amps is going to damage the board.
3A is the maximum that the battery can produce without damaging itself, but it will not produce those 3A without something that requires it - the energy needs somewhere to go. The ESP8266 draws very very little current, on the order of milli-amps, not amps. When you plug in the ESP (or really any electronic device), it will only draw what it needs. You could give it a supply that can produce 1A or 1KA, it will still only need mA to operate.
The concerns you’re having really apply to situation “A” that you listed in your original question. The ESP can be powered either by applying voltage to the V_in pin, or by plugging it into a micro USB. (One or the other, NEVER both). If you plug in a micro USB, the ESP uses that to put voltage onto the V_in pin. For very small projects, it is suitable to use the micro USB to power the circuit, and to use the voltage produced on the V_in pin to power your LEDs. HOWEVER, because the ESP requires so little current, it is only designed to handle ~1A moving from the micro USB to the V_in pin. If you begin to draw more than 1A (which you are very likely to do with LED strips), you are very likely to overheat the circuit and cause permanent damage to your ESP.
In order to avoid damaging your device, you need to make sure you’re following situation “B” from your original question - This way, both the ESP and the LEDs are drawing their own required power directly from the battery, and no extra current is flowing through the ESP.
Hi technomancer, this is me again, after ordering a sufficient and powerful power bank, I’m still stuck given the following two scenarios that I tested:
A) I’ve used a USB break out plug, then I have split the voltage positive wire into 2, one for the led strip and one for the VIN pin of an ESP32, did the same with the ground wire, split into two, one for the led strip and one for the GND pin of the ESP32, the thing is that once I turn on the strip, the strip draws almost all the voltage available and the split wires connected to the ESP have a voltage drop until 3.1 volts, not enough to keep the ESP working normally, therefore the strip is turned on, but I’m not able to connect to WLED nor to manipulate the strip
B) the power bank has two USB outputs, therefore, I used one to connect the ESP32 through the usb port, which makes it work perfectly, and the other USB port, has the break out usb plug and is connected to the strip, what happens is that if I power off the strip, after 8 seconds the power bank auto turns off due to low current draw from the strip, that gives me headaches because some effects leads the power bank to auto turn off, and despite the port of the ESP is working properly, I can not turn on the strip again until I plug and unplug the usb break out plug or do a reboot on the power bank, in both situations the ESP reboots as well, making me loose all the settings, due to WLED reboots as well.
I’m stuck again, lol, I would like to ask you if you did something to prevent voltage drop on the A situation or to prevent auto power off on the B, did you put something in between USB breakout pin and the ESP and the strip?.
Are you trying to keep this project portable? I definitely had a ton of weird issues when connecting directly to the AP. As a test, try configuring WLED to connect to your home wifi instead of using the AP, then return your wiring to this configuration:
Then just see if you can reliably connect to WLED and control your lights. I found this fixed my issues. In order to keep my project portable, I installed a second esp8266 on the same circuit and programmed that 8266 to be a router, then configured WLED to connect to that newly-installed 8266’s network. My gut tells me this is the issue you are having…
Otherwise, how many LEDs are you trying to control? Make sure you are using the “Automatic Brightness Limiter” setting, and have it configured so the current limit is equal to the rating of your battery pack (3A = 3000mA). This could help mitigate a voltage drop by reducing the overall power draw.
Some USB battery banks have a mode to disable the auto-off behavior you describe above, it is meant to allow very small devices to charge fully without being interrupted. I believe my INIU charger has you unplug all outputs, rapidly press the power button 5 times, then plug your outputs back in. I do not need to use this functionality to make my WLED work, but that may be because I have 2 8266s on the circuit.
If all else fails, you could always add an always-on LED or something to prevent the current from dropping below the auto-off threshold of your battery bank. If none of this helps, message me with your discord username and I’ll do my best to help you there! Good luck!
Hi there, after testing a couple of things I’ve realized that using the usb c output of the power bank keeps awake the power bank regardless if the strip is enlightened or not, so now I fixed it, besides that, everything were working perfectly, I’m using ESP32 and SK6812 144 led/m, I have to confess that I actually want to make a soft AP that can handle at least 18-30 clients with an additional ESP32 just to serve that purpose, but I’m still developing the main device, which is a fully portable led strip, so I might come back to you for some pointers in regard making a soft access point in order to be able to use WLED without internet access, whilst I still develop de main device, I also realized that instead of developing everything by myself, this actually has embedded everything I was looking for in terms of “controlling” the strip, take a look you might find it interesting for your projects and ideas https://dig2go.info/ this might be useful for your portable projects
New around here, but I haven’t seen many wearable projects here yet!
