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  • zkus commented on jiripraus's instructable Freeform LED Sphere
    Freeform LED Sphere

    Its been a long time since my EE class in college (im a software guy), so i am actually a little muddled on the proper placement. It looks like you've bridge the Vin and ground pins with the caps, and that might be ok, but i think they are actually suppose to go in front of the vin pin (so like from the power ring, to the cap, and from the cap to the vin pin).The point of the cap is to level out the voltage and/or current draw, so that each led is sipping steadily from the capacitor rather than from the noisy power line. I don't remember the exact physics of how this works though so i am not sure how much that placement matters (vague memory of it being unintuitive for me). @jiripraus may know better

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  • zkus commented on jiripraus's instructable Freeform LED Sphere
    Freeform LED Sphere

    So I love the look of this thing, and a lot of the skills to make it are in my wheelhouse. I wanted to add it to a project I was working on, and was trying to recreate the shell in fusion360 using some of the clever techniques you came up with.But for the life of me I can’t figure out how to you were able to arrange the led components tangent to the surface of a sphere like that. Do you have any quick hints on how you approached this?

    yeah you've successfully uploaded the code to your arduino at this point if i believe

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  • zkus commented on jiripraus's instructable Freeform LED Sphere
    Freeform LED Sphere

    The error makes it seem like you don’t have the neo pixel library downloaded (it’s an external lib so it isn’t there by default). There is a “manage libraries” option in the menu (on my phone right now and don’t recall the exact path) that will let you find and download the neopixle library from adafruit

    Looking at the datasheet, it looks like they suggest a capacitor of around 0.1 μF between each led. The point of the caps is help level out any spikes in voltage (or current?), which can degrade the lifespan of the part (I believe turning on or connect the battery will cause a spike, along with more random jitters)You can get tiny caps from AliExpress, but be warned the “smd” (surface mount device) style are bloody tiny, and would be a feat to solder on. If this is your first go at soldering this stuff you might want to skip those. The longevity might not be worth the effort. The resistors job is to limit the amount of current the less draw (without it they will suck up as much as they can, again limiting its lifespan and the batteries). I believe they suggest putting a 330 ohm resistor …

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    Looking at the datasheet, it looks like they suggest a capacitor of around 0.1 μF between each led. The point of the caps is help level out any spikes in voltage (or current?), which can degrade the lifespan of the part (I believe turning on or connect the battery will cause a spike, along with more random jitters)You can get tiny caps from AliExpress, but be warned the “smd” (surface mount device) style are bloody tiny, and would be a feat to solder on. If this is your first go at soldering this stuff you might want to skip those. The longevity might not be worth the effort. The resistors job is to limit the amount of current the less draw (without it they will suck up as much as they can, again limiting its lifespan and the batteries). I believe they suggest putting a 330 ohm resistor between the arduino datapin and the start of the led chain (don’t need one for every pixel)

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  • zkus commented on jiripraus's instructable Freeform LED Sphere
    Freeform LED Sphere

    Since “the algorithm” knows I like your stuff, I’ve seen a lot of your very distinctive) stuff show up unattributed by other people. I just saw this:https://youtu.be/joI94_MfKywwell you know what they say about imitation...

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  • zkus commented on jiripraus's instructable LED Jewelry
    LED Jewelry

    I’m late to the party here, but I think these tend to be ok because the internal resistance of those little buttoncell batteries is like 20 ohms (vs like <1 for an AA), which probablyly isn’t too far from the resistor value you’d pick

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  • zkus commented on jiripraus's instructable Freeform LED Sphere
    Freeform LED Sphere

    If i remember correctly, the WS2812b is only slighlty different from the WS2812 (i think its just rewired a little internally for reverse circuit protection). So it should be fine and work the the ardiuno code, just dont wire it up backwards

    Yeah that wire bender looks awesome. I’ve been wracking my brain to come up with a reason to justify making one. It looks like he has an instructabke for it If you look at his profile

    Yeah just saw that and came back here to warn the author. The price point is ridiculously low for how much hand crafted effort there would be, and there is no way a “productized” version was up and producing so fast

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  • The nice thing about the "overkill" led strip approach that you have is that it acts like a crude display. If/when i do this i was thinking of using that to display which of ~3 giant storage bins i put some large components (just having it display "top bin" as a string, or something like that)

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  • Awesome, yeah a quick note for the power would be cool. I believe the leds can pull up to 60mA per pixel at full brightness white (20 for each R G or B), but in practice i dont think ive ever had them run anywhere near that (except maybe for a quick "burst" animation)Once again, adore this project. Just ordered a bunch of parts for it. Did you happen to look at alexa over google home? I already have one, and am kinda assuming it has roughly the same api as home does.

    Love love this project. I am frankly a little bitter i never thought of it (all in my wheelhouse, and i totally have this same organizational issue).It does seem like your power system is overkill though (both for the number of splits for your power bus and the capacity of power supply). Ive made clothing with 300+ always-on ws2012 leds and got away with a fairly small usb battery (that could only push out an amp or so), and power bus connected just at the beginning and end of the strip big strip. I _think_ doing gamma correction also was a big help for the voltage issue (and just general power requirements). I would just set the brightness to like 80% (which, when gamma corrected, pulls something like half the current), and i _think_ that would in turn make it easier to supply the necess…

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    Love love this project. I am frankly a little bitter i never thought of it (all in my wheelhouse, and i totally have this same organizational issue).It does seem like your power system is overkill though (both for the number of splits for your power bus and the capacity of power supply). Ive made clothing with 300+ always-on ws2012 leds and got away with a fairly small usb battery (that could only push out an amp or so), and power bus connected just at the beginning and end of the strip big strip. I _think_ doing gamma correction also was a big help for the voltage issue (and just general power requirements). I would just set the brightness to like 80% (which, when gamma corrected, pulls something like half the current), and i _think_ that would in turn make it easier to supply the necessary voltage (since V = IR, and the resistance didn't change, but someone wiser than me should verify that).

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  • zkus commented on Asier Marzo's instructable Acoustic Levitator

    I saw a video (from "physics girl" where you had a model that was a half dome, and worked instead by creating nodes that were "like a pincer". Do you have a kit/plans for that version (i like the aesthetics of it better)?

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  • zkus commented on kenyer's instructable Fidget toy hand spinner

    A buddy of mine works with autistic kids and said these would be perfect for them, we are making a bunch.I am also going to try to make versions that light up when they spin, and are smaller for the younger kids hands (they enjoy the 2 and 3 pronged ones, and i think i can keep the prongs, remove the bearings, make them a little shorter, and fill the ends with bbs for weight)

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  • ElectroFrank's suggestions are entirely reasonable. You should treat high voltage equipment with the same over the top safety that you would a firearm (which can be obnoxious but effective). Just like a firearm, you can reach a point where a very casual mistake is basically _instant_ death with no chance of recovery, unlike your (honestly dickish) examples.You are not helping anyone by chastising someone for being safety conscious. If you think their suggestions are bad or incomplete, correct them, but don't yell at them just because you think you personally know better

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