Microcontroller Board (MCU)

To control the robot, we use an Adafruit Metro ESP32-S2. This is an UNO-shaped board, compatibile with Arduino shields. It embed an the ESP32-S2, a highly-integrated, low-power, 2.4 GHz Wi-Fi System-on-Chip (SoC) solution that now has built-in native USB as well as some other interesting new technologies like Time of Flight (ToF) distance measurements.

Guide

We recommand the Adafruit guide to the Metro ESP32-S2. It covers a lot of ground:

• Overview
• Pinouts
• Pin names
• Pin numbers
• ROM Bootloader
• Web Serial ESPTool
• Install UF2 Bootloader
• Welcome To CircuitPython
• Install CircuitPython
• CircuitPython Essentials
• Arduino IDE Setup
• Debugging with OpenOCD

Features Summary

• ESP32-S2 240MHz Tensilica processor - the next generation of ESP32, now with native USB so it can act like a keyboard/mouse, MIDI device, disk drive, etc!
• WROVER module has FCC/CE certification and comes with 4 MByte of Flash and 2 MByte of PSRAM
• Power options: 6-12VDC barrel jack or USB type C or Lipoly battery
• Built-in battery charging when powered over DC or USB
• Precision battery monitoring via MAX17048 on I2C
• UNO-shape so shields can plug in
• Reset and DFU (BOOT0) buttons to get into the ROM bootloader (which is a USB serial port so you don't need a separate cable!)
• Serial debug pins (optional, for checking the hardware serial debug console)
• JTAG pads for advanced debugging access.
• On/Off switch
• STEMMA QT connector for I2C devices
• On/Charge/User LEDs + status NeoPixel
• Works with Arduino or CircuitPython
• 53.2mm x 72mm / 2" x 2.8"
• Height (w/ barrel jack): 14.8mm / 0.6"
• Weight: 22.5g