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Archive for April, 2017
Posted by grmis | Apr 02, 2017 @ 04:35 PM | 11,309 Views

I have put some led ring on my FMS Super Scorpion EDF jet, for an afterburner effect. I took a flexible strip made with individually addressable LEDS (WS2812B 5050 RGB, also called NeoPixel). The price is about 14 euros on eBay, for 1 meter with 144 leds. For a 70mm fan, only ~35 leds are needed (the strip can be cut at the desired length).

An Arduino pro mini is controlling the LEDs (using the Adafruit_NeoPixel library). It reads the throttle channel (PWM signal, from the receiver) to vary the intensity and the color or the leds. I tried to make it more ‘realistic’, by including some slight (random) inhomogeneities along the ring, and some ‘flicker’ at high throttle. As for the color, it color goes from red, yellow, to blueish. This can of course be customized at will, by changing a few parameters. The Arduino code is available here:

Since each led can draw up to 60mA (under 5volts), the total current can exceed 1 amp, and this may be too much for some BEC. So, I am powering the arduino and the leds using a small adjustable step-down switching regulator (type mini-360). In my case the lipo is 4S. This small buck converter could work with 5S too, but not 6S (it would exceed the max voltage of the mini-360).

Ok, now comes the negative point: the luminosity is a bit too low, and the leds are barely visible if you are flying a sunny day I am going to change the colors a little bit in the code,...Continue Reading