DC motors, as we all know, rotate around an axis, allowing us to power rotary tools, mobile robots, and a wide variety of other devices. Getting one to create linear motion, however, is a bit more complicated. If you’d like a simple hands-on experiment to help show how it can be done, then check out this mechanismby Electro Techz.
Electro Techz's project consists of a small DC motor fastened to a cardboard base that turns a bolt. This bolt is threaded into a nut, which is attached to a piece of cardboard that acts as a mobile platform. This platform is restricted from moving rotationally by a pair of rods on either side of the nut/bolt assembly, causing it to move up and down linearly as the bolt rotates.
The setup is powered by a trio of 3.7V li-ion batteries, and controlled via an L293D IC and a pair of buttons. While it might not be the right choice if you’re going to build a CNC machine from scratch, as a learning tool for how linear actuators work, it could be the perfect hands-on activity. Given its use of extremely basic tools and glue, it looks like a great project for electromechanically minded kids – with the proper adult supervision of course!