I was recently making Bristle Bots with my niece and decided that a little over-engineering could enhance the experience.

These bots are normally held together with some double sided tape for both structure and electrical contacts.  While that's great to demonstrate how simple it is, it's also quite a bit… fidgety.  I designed this to bring a bit more structure to the bot and also make the battery removable without dealing with sticking/unsticking tape.

Parts

• CR2032 Coin battery
• Pager Motor - https://www.amazon.com/gp/product/B074P9SSSJ
• Toothbrush - Cut the head off.  Slanted bristles work best.
• Paperclip
• Pipe Cleaner

Assembly

For the battery contacts, I cut a paperclip in half, bent each piece 90° and inserted the rounded ends downward into the two slots.  This gives you springy contacts inside the battery compartment and leads on the outside for attaching the motor.

Using hot glue, attach the pager motor to the tray and the toothbrush head to the bottom of the chassis. 

You can either solder the wires to the paperclip leads or attempt to just twist them.

Optionally, put a little pull tab on the battery with some electrical tape to make it easier to remove.

Use a pipe cleaner to form legs to keep the bot upright.  The holes on the bottom provide lots of options for experimenting.

Have Fun!