For a couple years, I helped the Children’s Museum of Bozeman develop curriculum for their STEAMlab. I was always looking for fun ways to engage kids with electronics and coding. Minecraft is an easy way to get kids in the door and there are tons of resources for using it in fun and educational ways. Combining Minecraft and electronics was tricky, though. To help integrate Arduino projects with Minecraft, I ended up developing my own Minecraft mod named SerialCraft. The idea was you could hook up any device that used serial communication and send messages to and receive messages from Minecraft using my mod. Most Arduinos are capable of serial communication over USB, so it’s simple to wire up a circuit and send some data over the serial connection. I created controller kits that the kids could assemble and program to control their character, trigger and respond to Redstone signals, and to blink LEDs to alert them of certain events such as low life or when a creeper is near. This Instructable focuses on the creeper alert functionality and takes it a step further using Adafruit Neopixels and a laser cut acrylic and plywood enclosure. The Creeper Detector uses an 8 LED NeoPixel stick to give you valuable information about the nearest creeper. When all LEDs are off, it means there are no creepers within 32 blocks. When all LEDs are on (theyll be flashing as well), youre within the 3 block detonation radius of the creeper (the radius at which the creeper will stop, light its fuse and explode). Anything in between can give you an estimate as to how far away a creeper is from you. When 4 of the 8 LEDs are lit, youre about 16 blocks from a creeper, which is the range at which if a creeper sees you, itll attack. The LEDs will begin to flash when youre within the blast radius of the creeper (7 blocks). Its also the radius that if you step out of, the creeper will stop its fuse and continue to come after you. With this knowledge, you should be able to avoid any unexpected creeper attacks or hunt down any nearby creepers!
In this Instructable, well go over everything you need to create your own Creeper Detector and how to install and use the SerialCraft mod that allows you to interface Minecraft with your Arduino projects. If you like it, please consider voting for it in the Minecraft Contest and Epilog Challenge. Let’s get started!”

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