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Adressable LED connections and luminosity difficulties + portable design questions

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gotchock

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Hello, total newbie here in DIY electronics (but engineer), sorry if missed an existing answer on the forum:

I'm working on a wearable light project involving 11 adressable LED strips (WS2812b / 30cm per strip) connected in parallel to a controller powered by 1 lithium battery (18650) in 5V through a booster/charger chip (see enclosed picture). All the power/control is attached to a stick hand-held (compact design).

I have several questions on which i struggle to find a solution, and i think maybe someone with more experience can help me ? I don't really know where to look for answers, it's pretty specific...
  1. I'm using 144 LED/m WS2812b strip to show a continuous line of light instead of spaced out dots (every strip is short), but at the cost of increased power consumption and harder soldering on smaller connectors. Is there a way to obtain a "light line" effect with less LED like a diffuser or different LED technology ?
  2. LED are actually TOO bright even at 3-5% level. If i go lower than that (1-3%), I can do less than 10 colors in total which is not enough... The solutions i found are to cover each LED with white paint (time consumming and does not reduce much luminosity), or stick 2-3 double face tape over each strip (not super strong and also time consumming, but works). Are there similar LED strips with less overall luminosity, or cleaner solutions to reduce it like ND filter tape ?
  3. Each of these strips is moving a lot relative to others & controller, sometimes fast. This is putting a lot of strain on the wire solderings, even though i'm using heat-shrink tubes. After a few hours of use, i got a connection failing by a wire that broke next to the solder. I tried finding proper connectors to avoid soldering, but they are usually too big (should be as flat as possible), or allow connection of only 1 wire (impossible for my parallel circuit). Any idea to have stronger connections on each LED strip ? What about crimping headers + heat shrink ?
  4. My whole system is an assembly of separate components:
    • battery case
    • booster 5V/recharge/protection card
    • on/off switch to isolate the controller (else it's drawing power even when LED are off)
    • controller
    • Any recommendation on where to look to find a way to encase these different components in a "long" case to be attached to a stick carried by hand ?
Thank you very much !
 

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Use "extra flexible" wire and progressive strain reliefs - eg. very stiff over the joints, then progressively more flexible further away, using thinner material or less layers etc.

If done properly, there should be no "kink" point when the wire flexes, it should form a smooth curve.

As long as the flexing sections are long enough so the bend radius is never too small, they should last years.
 
Use "extra flexible" wire and progressive strain reliefs - eg. very stiff over the joints, then progressively more flexible further away, using thinner material or less layers etc.
That's what i've been doing (silicone wires, heat shrink layers), but it seems it stills strains the board of the LED strip (despite the heatshrink around the extremity of the strip), and unsticks the conductor alltogether with the soldering, or breaks the cable inside the heat shrink...

Do you think it would be stronger to weld directly a connector header male (+ epoxy sticking eventually), then connect to it properly crimped cables ? Is there a way to crimp 2 cables together into a connector that goes to the header ?

Sorry about the noob questions, i have a good idea of WHAT i want to do, but i'm lacking experience on HOW to do it, so i'm maybe thinking of innefficient ways. Note: i plan to to repeat this project in the future (will try to sell it), so that's why i'm looking for the most reliable/repeatable solution i can find.

Thank you
 
If the wires will be under tension, rather than just flexing under their own weight, you need to add a cord that is mechanically attached at each end, to prevent the wires from being pulled.

If they are detaching while flexing under their own weight, then there is a definite problem with the soldering and physical strain relief.
 
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