One of the simplest ways to make a mobile robot involves differential steering, where two wheels move at different speeds as needed to turn and a ball caster keeps it from tipping over. The MrK_Blockvader is an excellent take on this type of bot — demonstrated in the first clip below — featuring a nice blocky body comprised out of 3D-printed parts, RC truck wheels driven by tiny gear motors, and an integrated roller on its back.
The MrK_Blockvader is controlled via an Arduino Nano, along with an nRF24 breakout that allows it to receive signals from a radio transmitter unit. The build includes LED lighting as well as a piezo buzzer for all the beeps and boops. It can also take advantage of various sensors if necessary.
The eventual goal is to use the MrK_Blockvader in a network of robots, hinted at in the second video with a worker at its side.