The robot is controlled by Arduino board. Simple algorithm allows detecting obstacles with two front bumpers.
Power bank with lithium battery provides power for one hour run. Solar cell in theory may charge it but has low capacity.
This robot uses 12 volt computer cooler turbine with vertical dust bin container.
Step-up circuit built on MC34063 provides 12 volts from 5 volt battery.
Motors have 20 RPM with 6 volts. They are controlled by H-Bridge motor driver built with HG7881 module. Wheels were bought in a hobby shop – they supposed to be set on a flying model. They have good rubber surface so should not slide on the floor.
Rear caster wheel is made from two bearings.
Base is made from plastic kitchen board. This material is easy to drill and saw, it is good dielectric. Thickness 8 mm lets screw bolts which confidently keep components on places.