This simple robot is based on the E3BOT/COGLABS 3d printed chassis.
I only changed the ESP32 for an Arduino MKR1010.
https://www.trezorium.com/wip_coglabs/index.html
https://www.e3bot.com/p/instructions-software.html
https://www.trezorium.com/wip_coglabs/building_instructions.html