🏯 🔣 🦖 LED costume 💤 🚥 🙍🏿

This is the first part of my publication in which I will try to briefly and concisely outline the technology for constructing a modern LED costume.

For more than 4 years, digital LED strips based on IC LED chips (smart pixels) have been available on the market. The essence of these pixels is quite simple, an integrated microcircuit that controls it is integrated into the RGB SMD / DIP LED. Such tapes provide high density - 144/100/60 pixels per meter, low weight, low voltage, and ease of control of an external controller.

Among the most common and popular LED chips can be distinguished: WS2812B, WS2813, APA102, SK9822, UCS1903 with a power supply of 3.5-5V. IC LED chips with + 12V power are also gaining popularity now, these are WS2815, GS8208.

Each pixel of such a tape can be individually controlled, as well as a pixel on the monitor screen, i.e. this makes it possible to build an advanced LED suit or “Pixel suit” based on a digital LED strip.

It is rational to choose bulk 3.7V li-ion batteries as 18650 batteries, in a 18650 or 26650 case, high current (25-50A). To purchase such batteries is not difficult, just look at any vape store (electronic cigarette stores).

A working voltage of 3.7V is enough to confidently control the chips of the manufacturer WORLDSEMI CO., LIMITED: WS2812B, WS2813, etc. It should be noted that the disadvantage of low supply voltage is the high operating currents. One pixel with 100% white color consumes a current of about 51 mA, and if we take into account that in a modern LED suit there are more than 1000 pixels, we get a peak total current of more than 50A.

Using IC LED chips with a + 12V supply voltage greatly reduces the load on the power circuit. You can use batteries with protection (not high current), choose wires with a smaller cross section. For reference, one WS2815 IC LED chip consumes a current of about 10 mA, with a supply voltage of + 12V and 100% white. But with this approach, you will have to look for a battery with an operating voltage of + 12V or connect 3 pcs. + 3.7V 18650 in series. Another drawback is that the IC LED chips themselves have quite large quiescent currents - about 2 mA, compared to 0.6 mA for chips with a low supply voltage (WS2812B, WS2813, etc.). Perhaps at the time you read this article, manufacturers have already finalized this defect.

As in the case of a PC, to work with graphics, and in our case, LED animation, you need a graphic controller and playable content. Content can be on any medium: SD card, Flash memory, Wi-Fi channel, or even synthesized by a graphics controller.

The tasks of the graphics controller are as follows: -
read from the media and convert the graphic (video) content to a low level;
- output low-level data (content) to the signal lines of the digital tape at the right time;
-Synchronize with other controllers;
-Receive and process external control commands, for example, via the DMX bus.

Everyone chooses the basis for mounting LEDs based on their task and design of the LED suit. It can be ABS plastic, PET (or PET, polyethylene terephthalate), organic glass, aluminum, etc.

Ready-made frames in the form of masks and protective shells of sports equipment can also be used as the frame of an LED suit.

This photo shows a typical airsoft mask.

As conductors, you can choose AWG soft stranded silicone wires. Such wires can withstand both low temperature -60C, and high up to + 200C.

Silicone insulation, tinned copper veins make the wire very flexible, which makes it easy to work. The required conductor cross-section should be selected based on their rated current according to the current cross-section of the cable. As connectors father-mother elements of the suit can be used power connector PATA-devices (Molex 8981).

In the next part, I will talk about how to prepare animation and convert content for playback on an LED costume.

LED costume

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