These are 3D printed brush (or bristle) bots, a fun take on a popular STEM project.

Print with the legs UP and use supports for the inside compartment.

You will also need a pager motor, batteries and a switch. Full directions on my website, stldenise3d.com. A plain base is included to add your own custom legs. Photos show VibroBug topped with Flexi Rex & Cute Mini Octopus at 75%.