Perhaps you’ve seen combat robotics competitions like BattleBots and Robot Wars, and wondered how you could build your own destructive device. If so, then check out this guide to constructing a fully functional, 3D-printed version of your own using Tinkercad by “CombatRobotGuy15."
The write-up outlines a few choices for weapons systems appropriate for the Antweight (one pound) robot class, including a horizontal spinner, vertical spinner, and drum spinner. It then goes on to describe in more detail how to design your own drum spinner, which is “capable of dealing out large amounts of kinetic energy” with “screws’o doom” attached to the printed drum using inserts.
Electronics are similar to what you’d find on an RC car, with a powerful brushless DC motor controlled by an ESC implemented to handle the drum's spinning. A bearing holds it on the opposite side of the motor to reduce friction.
If you’re wondering what this type of robot/weapon combo can do, CombatRobotGuy15 claims to have sent a can flying 15 feet with a similar 'bot. As more proof of its destructive prowess, a drum-bot is also featured in the video below, mopping the floor with the other participant. The ending, however, is indeed quite surprising!