How to build a BrushBot

BrushBots are super simple mini robots that only need a few bits of inexpensive kit to create. All the materials can be reused in other robotics projects too. They are very easy to build and can be customised in lots of different ways!

These mini robots can be made as a class science project, simple STEM challenge or just for fun!

Materials needed to make a BrushBot

AA battery and holder

1.5-3 Volt DC motor

Motor holder

Small brush

Hot glue gun or double sided tape


Labelled diagram of a BrushBot for a STEM project

How to build a basic BrushBot

First plan how you are going to create the circuit. The motor and motor holder needs to be on one end of the brush and the cork needs the space to spin freely.

Use either glue ( we used a hot glue gun ) or strong double sided tape to hold the motor holder in place.

Put the motor inside and attach the cork.

Fix the battery holder and battery on the brush making sure the wires can reach the motor.

Attach the wires from the battery holder to the motor and check it spins.

Place the mini robot on a floor with a smooth surface.

The BrushBot should move wildly around on it’s own!

BrushBot made with a small children's hairbrush.

We added a switch to the bigger brush, but this isn’t necessary and added a bit of weight to the robot which slowed it down.

BrushBot Troubleshooting

For the motor to spin the circuit must be complete. If it’s not spinning check the wires are connected to the motor correctly. Electricity needs a closed circuit to flow.

If the cork is spinning but the BrushBot isn’t moving, try changing the position of the cork so it’s slightly off centre. This will make the brush wobble more and move more easily and dramatically!

Make it fancy!

Now you’ve got a basic BrushBot model you can customise it! Add faces, decorations or even pens to turn it into a drawing robot!

BrushBot with pens attached so it draws as it moves
BrushBot drawing robot

BrushBot Investigation Ideas

Build two BrushBots and race a friend.

Experiment with different size and shape brushes.

Find out what happens if you change the spinning part to something longer or shorter or make it slightly off centre.

More Robotics Projects for Kids

Build a simple drawing robot using a similar technique to the BrushBots.

scribble bot drawing robot made with a motor, cork, battery, pens and a pringles pot!

Make an articulated hand grabber using cardboard and split pins.

Last Updated on May 30, 2022 by Emma Vanstone

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