This thread is for anyone working on personal projects to share their progress, and hold themselves somewhat accountable to a group of peers.
Post your project, your progress from last week, and what you hope to accomplish this week.
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Notes -
I'm kind of tempted to make TRON style lights for my bicycle helmet, bicycle and vest for myself and my family. A central controller would broadcast what LED should display what color. This way when we cruise around town we can all have synchronized lights and look absolutely sick.
I'm not really worried about doing the Arduino/ESP stuff or the wiring, but I would like to avoid buying a bunch of random stuff blindly and struggling with various LED light technologies. Anyone familiar with what I actually want? Regular very common LED light strips are too dim to use during the daytime. Thoughts?
There's a lot of good information on the WLED discussion boards (and, unfortunately, Discord). If you want to skip the programming side, WLED as a program is also pretty strong, if not necessarily well-documented.
Most of the NeoPixel/DotStar (or simple one-channel RGB 'mood lighting') strips intended for direct Arduino use will cap out around 60 mA per LED, simply because that's the cheapest and easiest configuration for the chips. Adafruit has some ultrabrights, but they're a nightmare of a form factor and probably too bright for what you're doing, even in the day. If you're willing to print out your own circuit boards, getting big LEDs onto a WS2814 chip is an option, but soldering the big heatsinks those LEDs come with onto a flexpcb is not an easy task, even with specialized tools.
Unless you're willing to deal with individual heatsinks on the ribbon, the easy tradeoff is just going with more LEDs in a smaller form factor. You can get individually-addressable ones up to 120LED/m this will have almost four times the brightness of a 30LED/m cheapo strip, along with better resolution. The WS2814s or APA102s are usually going to be the brightest in a given form factor. Going to higher voltages won't get you that much extra brightness, but it will have an impact and drastically simplify the wiring for even moderately-sized runs due to voltage drop issues, so 24v is probably the easiest to do with a 'normal' setup. This does significantly complicate the driver board, though.
Circuit-on-board options would be even brighter, but they're generally not going to have as high a resolution, and a lot of COB boards can only address 'zones' of multiple LEDs (sometimes over an inch per zone, which is how these COB strips advertise such high LED/m values). That said, do look closely at any purchase option; even 'standard' neopixel strips on are often zone-based (cfe here at 120LED/m and 20 zones/m, or here at 896 LED/m and only 16 zone/m). Low zone density will usually result in lower brightness when compared to a (admittedly often theoretical) strip of the same LED density.
Depending on the complexity of your intended LED patterns, this may or may not be an acceptable tradeoff.
WS2815s are always going to avoid zones and can be found in much higher density, but they're individually much less bright (at the benefit of being much more power-efficient) and only go up to 12v, along with having higher passive power draw. If you need a lot of detail and don't want to have to fuck with 24v power, the 300+LED/m strips might be worth looking at. I'd still recommend grabbing a sample unit and making sure it's bright enough.
How do the drivers for these work? Is it the simple series string + a resistor you see in a lot of lighting strips, or does it use a current limited supply?
I've been wanting to set up a DC led lighting system because I'm so sick and tired of the crappy built-in bulb power supplies, but actually driving these things off a varying battery voltage is kinda difficult
NeoPixels (WS28xx), DotStar (APA102/SK6812/SK9822), and most circuit-on-board designs do their own current control for each (zone of) LED -- the only real challenges for implementation are making sure you don't have too much voltage drop (because current control can't adjust for input voltage below the forward voltage drop), and if so just running additional power connections to the middle of the strip. They're not great for room lighting because of the color quality, though, even the RGBW variants, and diffusers only help so much. They're designed for constant voltage drivers; using a constant current power supply can cause problems ranging from comm issues to drastically reduced lifespan.
Cheap RGB lighting strips will almost universally do the series+resistor thing, as will even some decent single-color room lighting. Constant-current drivers and LED strips built for them exist, but you're usually stuck with very specific lengths of LED strip as a result; unless you really need the extra brightness uniformity, I dunno that I can really recommend any.
If you're trying to work with battery voltage to a non-current-controlled output, I really recommend a buck-boost-buck voltage stabilizer. You can get 12v ones for small or mid-sized applications that will handle the full voltage range you want to run a lead-acid battery down to, and are good on output within about 5%. Only downside is that they don't like starting in <-10F cold temperatures.
I got a cheap 10A (<5A realistically) one of those, 24->12. I don't have any way to test ripple, but at least it'll be easy to see if it makes LEDs flicker. Some of the chineseium power electronics is amazing, some of it's absolutely terrifying.
It's weird that for all the problems AC LED lighting has, DC is somehow no better lol. Seems like that's true of a lot of stuff that you'd think direct DC would be good for.
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