The 3D printed prototype made by the U.S Navy is considered legit. ... Homemade 3D-Printed, Handheld Railgun With Arduino Uno R3 Inside Fires Projectiles At 559 MPH. By Quinten Plummer ...

Arduino Uno - The World's Most ... shield compatibility and 5 V power supply of the popular UNO R3, ... branching out into products for IoT, wearables, 3D printing, and embedded environments.