Bristlebot: The No-Code Toothbrush Vibrobot
Build a fun, no-coding tiny robot that skitters across tables using a toothbrush head, a vibrating coin motor, and a 3V coin cell battery.
The classic introductory robotics project! A Bristlebot converts high-frequency mechanical vibration into directional linear motion through slanted brush bristles. It requires zero programming and zero soldering, making it the perfect first build for all ages to understand center of gravity, friction, and kinetic resonance.
Bill of Materials (BOM) & Components
| Component | Specifications | Qty | Estimated Cost |
|---|---|---|---|
| Slanted-Bristle Toothbrush Head | Cut off brush head with forward-slanted nylon bristles | 1 | $1.00 |
| Micro Vibrating Pager Motor (Disc or Coreless) | 3V DC, 10,000 RPM eccentric rotating mass (ERM) | 1 | $1.50 |
| CR2032 3V Lithium Coin Cell Battery | 3.0V nominal, 220mAh capacity | 1 | $0.80 |
| Heavy-Duty Double-Sided Foam Tape | High-adhesion vibration dampening foam | 1 | $0.50 |
| Mini Slide Switch or Paperclip Jumper | Used to connect/disconnect battery without peeling tape | 1 | $0.30 |
Electrical & Architecture Summary
A direct series DC circuit: Positive (+) lead of the 3V coin motor connects to the positive top surface of the CR2032 battery; the Negative (-) lead contacts the bottom negative face to complete the circuit and activate vibration.
Step-by-Step Assembly & Configuration
Preparing the Toothbrush Head
Using wire cutters or a small hacksaw, cut the handle off an angled-bristle toothbrush right at the base of the head. Clean off any plastic burrs.
- Inspect the bristles: ensure they angle uniformly toward the rear of the head.
- Wipe the flat plastic back of the toothbrush with rubbing alcohol for strong tape adhesion.
Mounting the Foam Tape and Motor
Stick a square of double-sided foam tape onto the flat top of the toothbrush. Press the vibrating motor securely onto the front half of the tape.
- Stick the negative (blue or black) wire underneath the foam tape so the bare copper wire touches the battery placement spot.
- Position the motor spinning weight so it can rotate freely without catching on the tape.
Connecting Battery & Tuning Center of Gravity
Press the CR2032 battery firmly onto the foam tape (negative side down). Touch the red positive motor wire to the top of the battery to start motion.
- Tape the red positive lead with a small piece of electrical tape to maintain continuous contact.
- Place the Bristlebot on a smooth, flat table and observe its movement.
- If it leans or spins in circles, adjust the battery position forward or backward to balance the weight.