R12 is my latest robot. It's cut from 3mm aluminium sheets with my CNC v3.2.2 (see my 2018 HackadayPrice entry):

The central brain of my rover is a SIMATIC IOT2020, two servos for continuous rotation drive the vehicle, a normal servo tilts the IP camera, four LEDs are used as headlights and a flashlight on top prevents (hopefully) that the vehicle is overseen when driving on the floors of maker fairs.

It's a very sturdy design.