WeMos D1 Mini ESP8266 LED Bar Case

prusaprinters

This is a case designed to hold a WeMos D1 Mini ESP8266 microcontroller and a strip of addressable LEDs. The ESP8266 can connect to a data source and display status on the LEDs. I use it to read out the status of my garage door and other sensors in my home. The ESP8266 connects to an MQTT message broker and receives messages to control the LEDs.I printed the body in black ABS and the lens in clear ABS. Other materials would work well. The lens doesn't have to be clear. The LEDs are very bright and will be easily visible through white material. Other colors will also work, but will filter the color of the LEDs.The WeMos D1 Mini is a self-contained ESP8266 board with the ESP-12F microcontroller, a 3.3v regulator and built-in USB UART. They are readily available from a variety of sources. Official WeMos Store*This site contains affiliate links for which I may be compensatedI used five WS2812b LEDs cut from a strip containing 60 LEDs per meter. These are also available all over eBay. Find WS2812b LED strips on eBayYou can also purchase WS2812b LED strips at Amazon.You can see in the photos that I added an additional SMT chip onto the microcontroller. This is a schmidt-trigger hex inverter used to convert the 3.3V output of the microcontroller to the 5V input of the LED strip. This is not necessarily needed. In most cases, the 3.3V output will drive the LEDs just fine. I just wanted to try the proper level converter to see if I could make it work.Demo video here: https://youtu.be/nMmwOEkX5KoPrint SettingsPrinter:MakerFarm Prusa i3vRafts:Doesn't MatterSupports:YesResolution:.2mmInfill:40%Notes:Supports are necessary to print the raised lip on the body pieces.rnrnPost-PrintingPrint CleanupDepending on your printer and slicer, the support material may leave a rough surface on the lips of the body that fit into the lens. After printing and removing the support material, you can sand or file down the rough surfaces so the lens fits correctly. The rough surfaces will be covered by the lens and will not be visible.Gluing The Case TogetherI glued my case together using Testors Plastic Cement, available from Amazon.rnrnAfter dry-fitting everything to make sure it fit, I disassembled it and brushed liquid cement onto the mating edges of the case. I let it sit for about 30 seconds and then assembled it. I also brushed cement on the front lips of the body and the mating surfaces inside the lens and pressed the lens on.rnrnI bound the parts together using zip ties and a vise and let the cement set for about 30 minutes.rnrnThe vise I used is a Panavise Jr. I also used it to hold the parts while soldering.How I Designed ThisFusion 360 ModelThis was designed using Fusion 360. You can get the original design files here: http://a360.co/2aiOI76Custom SectionCodeHere is a NodeMCU script to exercise the LEDs:rn rn local NUM_LEDS = 5;rn local i = 1;rn local d = 1;rn local hue = 0;rn rn rn local function hueToRgb(hue)rn if hue >=0 and hue < 60 then return 255, hue255 / 60, 0 end;rn if hue >=60 and hue < 120 then return (120-hue) 255 / 60, 255, 0 end;rn if hue >=120 and hue < 180 then return 0, 255, (hue-120)255 / 60 end;rn if hue >=180 and hue < 240 then return 0, (240-hue) 255 / 60, 255 end;rn if hue >=240 and hue < 300 then return (hue-240)255 / 60, 0, 255 end;rn if hue >=300 and hue < 360 then return 255,0,(360-hue) 255 / 60 end;rn endrn rn rn ws2812.init()rn local buffer = ws2812.newBuffer(NUM_LEDS,3);rn buffer:fill(0,0,0);rn rn tmr.alarm(0, 50, 1, function()rn hue = (hue + 1) % 360;rn local r,g,b = hueToRgb(hue);rn rn i = i + d;rn if( i == NUM_LEDS ) then d = -1 endrn if( i == 1 ) then d = 1 endrn buffer:fade(3);rn buffer:set(i, r,g,b);rn buffer:write();rn end)Category: Electronics