Brush bots (or BristleBots) are a classic STEM project invented by Evil Mad Scientist Laboratories that introduces kids to robotics with a very basic motion system: vibration. They’re usually made from toothbrushes, coin batteries, a tiny motor and tons of tape. You can see how to make traditional brush bots over on my mom blog, stlMotherhood.
Fun fact: Hexbugs ripped off their idea from the fine folks at Evil Mad Scientist Laboratories, who first introduced the idea in 2007. Like a lot of us in 3D printing, the EMSL are fans of Open Source and love to share their ideas…and credit them. Thank you EMSL for the brilliant idea!
3D Printed BristleBots
Getting toothbrushes to travel straight was always a weak point of the original craft, so we’ve come up with a way to 3D print a bot. I made this in TinkerCad — which is beginner level 3D design software you can use for free. It’s made for students, but people of all ages can use these simple tools to get basic ideas out of your head and onto your 3D printer.
Our bot is a tiny bit more complex than the tape-it-up style of the original, but this is also more durable for continued play. We’re using a battery holder and switch, which calls for some simple wiring.
Disclosure: Some of the links on this page are affiliate links, meaning, at no additional cost to you, I will earn a commission if you click through and make a purchase.
Parts for a 3D Printed VibroBot
LR44 Button Batteries: You can buy these in bulk from Amazon and really save some money
Coin Button Battery Holder: proper holders lets you replace the batteries
Pager Motors: Tiny motors to make it move
Wiggly Eyes: Googly eyes make it fabulous
STL Files for 3D VibroBot
The files are free, and I posted them on both Printables and Thangs so you can use the platform you like best. These are not for commercial use! These files are only posted so you can enjoy them and share them with your kids, your friends kids, your scout troop, your classroom. But do NOT sell them.
If you use the links above, it will cost about $38 in supplies and make 5 complete bots with a few (ahhem) extras. Feel free to use my shopping links as a jumping off point! Each complete bot is only $3.40 when you buy your supplies in bulk. Not too bad when you consider that a Hexbug Nano is $17 a piece and doesn’t give you the creative fun of Do It Yourself.
We took these bots to MRRF 2023 for our table. Rick used all the motors, making 15 bots, but that required a bit of tape and soldering since we only bought 5 of the reusable holders.
If you get the battery holders you can just hot glue the wires in place!