Bristlebots are an easy, and fun project to do using the head of a toothbrush, a battery, and a small motor. Once completed, they buzz along the top of a table! In this activity, we’re going to build one Bristlebot with straight bristles and one with slanted bristles and race them to see which is faster!
What You Will Need
- 2 Coin cell batteries (1.5 V or 3 V)
- 2 Vibration motors (a good source can be found here)
- 2 Toothbrush heads, one with slanted bristles and one with straight bristles, with the handles cut off
- Double-sided foam tape
- Scissors
- Googly eyes, pipe cleaners or felt for decoration
- Flat, smooth surface like a table or countertop. The robots will not work on rough surfaces or carpet.
Instructions
- Prep all your materials, get an adult to help you cut the head off each toothbrush, and cut a piece of foam tape the size of the top of each one.
- Apply a small piece of foam tape to the top of the toothbrush robotic platform, which will be used to hold the motor in place.
- Attach the motor to the foam tape. The tape provides a spacer so that the rotating weight does not hit the toothbrush head. It also provides a strong, flexible connection to the base to handle the severe vibration that this robot experiences.
- Bend one of the leads down flush with the foam tape, so that you can *stick* the battery to the foam tape as well and still make an electrical connection. The other lead contacts the other side of the battery, and the motor can run.
- Does your Bristlebot run straight? Does it fall over? Battery and motor placement, bristle shape and how the whole thing is balanced can influence movement. Try flipping the battery upside down or reversing the orientation of the motor if you have trouble getting yours to go straight.
- Decorate with googly eyes, pipe cleaner antennae or felt wings, make it your own!
- Now make your second Bristlebot and race them! Or, try building a maze and see if your Bristlebot can escape.
What other type of robots do you think you can make with a small vibrating motor and a battery? Experiment with shapes and materials and see what you can come up with!
