This Simple Bot was inspired by a work by artist James Rouvelle, called Colony, in which a bunch of odd-shaped ellipsoids self-propel around their environment. It is my understanding that his bots were made by placing a vibrating motor freely inside of a Styrofoam ball that was then coated to give it an irregular shape. This dynamic makes his orbs fluctuate between wobbling in place and jerkily moving around the room. While this is a cool interaction, I was more interested in making something that had a more regular motion and was able to roll steadily about. Towards this end, I have created Rolly Bot. To simply explain, Rolly is basically an over-sized tennis ball with an over-sized bristlebot placed inside. This allows Rolly to be rolled in whatever direction the bristlebot inside so chooses to drive.
Remove the handle from your scrub brush with a pair of cutting pliers.
The surface should now be made completely flat. Use your cutting pliers to trim off any remaining plastic. If that proves too difficult, you can cut off any plastic stubs with a coping saw (or hacksaw).
Place a small piece of paper between one end of a battery and the battery holder. This piece of paper will prevent the motor from turning on right away when we make the electrical connection in Step 5.
Place the battery holder atop the scrub brush and the motor atop the battery holder. Zip tie them all together. This may take a little bit of patience, but should be fine once you get the first tie pulled taught.