If you don't want to complicate with the electronics you can simply paint the batteries in the corresponding color.
Material
-A battery to power the circuit.EEMB Lithium Polymer 3.7V 2000mAh Battery 103454
-ESP32 wroom of any other controller
-A TP4056 module USB 5 V 1 A 18650
-Any addressable led strip
The project consists of 4 major pieces in total.
the head, the body (x4) and the batteries (x8) and the piece that supports the electronics.
1 ) the head consists of the main piece and two others that are to mount the switch. the idea is to use a switch to mount it in the big piece and in the button to glue the smaller piece. the switch should be glued to the bottom of the main piece through the hole.
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2) WLED: (Find a tutorial on youtube to install on your divice is pretty easy)
to configure the LEDs must be sectioned into 8 segments with a length of 10 LEDs (depends on how many leds you are using per battery).
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EACH SECTION IS ACCESSED WITH A GPIO OUTPUT in this case use GPIO 15,2,0,4,13,12,14 and 27. this leaves one configuration for one input.
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to do this you go to config then led preference scroll down untill Led OUTPUTS and then you introduce the lenght and the GPIO then add another one untill you finished with 8 outputs
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Now your must select the color that you prefer and save it as a preset (on the right side of the home menu) and configure it, in led preference, so that when it turns on this is the one that is loaded (use the ID that the preset gives you).
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The led has 3 terminals, the ends for power supply and in the middle for data, this is the one that must be connected to the programmed output.
It should look like this:
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3) the batteries consist of 3 pieces the cover, the main body and a support for the leds. An addressable led strip was used and connected as follows.
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the wires of the led connections must pass through the hole of the led holder so that no wire gets in the way of the light.
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for this part you can use 4 to 6 leds per side which equals 8 - 12 leds. in this case i used 5 per side to have good brightness. Just glue it
it is recommended to test the leds already assembled each battery to avoid problems later.
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4) Each piece of the body has two openings for the batteries, which must be placed with care because it is a delicate part that often breaks.
The bottom piece will be placed a support for electronics.
In this case I used an ESP32 WROOM only because I already had it but it is advisable to use a smaller controller because the space is very limited to work with.
you can try to scale up 10% up to make the next steps easier (no tested).
5) now the assembly part, make sure you connect everything you need because the disassembly to check or correct it will be more difficult.
Remember that ESP 32 will be supplied through pin V5(+) and GND
You must be patient and careful when mounting all and the wiring.
you must connect the battery to the TP4056 module and the output of this will be what supplies the power to the circuit (see TP4056 DATASHEET or look it on youtube). the idea is that the positive cable should be large enough.
to go through the entire structure and the negative side just solder it with another negative that is close.
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A recommendation is to pass the wires coming out of the batteries (the leds) behind Large-support to better manage the wiring.
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when you finish soldering the power and signal wires solder an extra wire for the power supplies so that it reaches the next segment.
Before moving on to the next segment I recommend that you test the LEDs to make sure that everything went well.
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After repeating this three times, at this point you should ended up with a wire the is from the TP 4056 Module and other positive wires that connect through the circuit
just solder them to the switch and assemble the head.
And Congratz you Finished.