Hopper Moves with a Gearmotor and Springs

While most hacks seen here involve a microcontroller or at least a hefty dose of discreet electronics, the aptly named “Hopper” moves using only a gearmotor and a pair of springs. The device, by creator gzumwalt, features an on/off switch for control, and runs on a small 100mAh LiPo battery. When switched on, the motor turns a crank mechanism, which slowly pushes the springs tight, until it releases them with a sudden jolt. The result is that the motor and battery masses are flung sharply upwards and at an angle, causing it to jump in the air, over and over again as the motor rotates.

The Hopper is inspired by battery-powered hopping toys of yesteryear, and is meant to demonstrated the difference between kinetic and potential energy. It’s also designed to entertain gzumwalt’s grandkids, and it looks like a lot of fun for adults as well. The device is built from seven 3D-printed components, as well as six purchased parts, which are pretty common and/or could be substituted as needed. So if you have a fairly well-equipped shop, you might even get one hopping around today!

Print files and build instructions are available on Thingiverse, and you can see a demo of it in action — including some great slo-mo footage — in the video below!