/ESPHomeRC-RetrofitCar

Retrofit of an old RC car with an ESP32-CAM module with Open Source firmware

Retrofit RC car

TL;DR

I retrofit an old RC car with ESP32-CAM module and wrote an
Open Source Android app ESPHomeRC to control it via WiFi.

a test rig with a RC car
click for higher quality video
a test rig with a RC car
click for higher quality video

The Hardware

Bill of Materials

besides an old RC car stripped of the electronics you need:

  • an ESP32-CAM module like this ~15 Euro

  • H-bridge module (based on L298) like this ~5 Euro

  • two Li-Ion 18650 batteries like these and a holder ~25 Euro

so the total cost should be below 50 Euro

The Assembly

ESP Pin H Bridge
GPIO3 / VOR in1
GPIO2 in2
GPIO14 in3
GPIO15 in4
GPIO12 en1
GPIO13 en2

The Firmware

The firmware is completely open and easily hackable. It is based on . You just describe your setup in a yaml file and a firmware will be generated.

Preparation

Install

Build and upload

Get a 3.3V USB to serial adapter (like this) and connect it:

ESP Pin ... to
GPIO0 GND
3.3V 3.3V
VCR RX
VCT TX
GND GND
> esphome rccar.yaml run 

...
RAM:   [=         ]  13.4% (used 43816 bytes from 327680 bytes)
Flash: [=====     ]  51.4% (used 942546 bytes from 1835008 bytes)
Configuring upload protocol...
...

Now briefly press "RST".

Connecting........
Chip is ESP32-D0WDQ6 (revision 1)
Features: WiFi, BT, Dual Core, 240MHz, VRef calibration in efuse, Coding Scheme None
Crystal is 40MHz
MAC: ...
Uploading stub...
Running stub...
Stub running...
Configuring flash size...
Auto-detected Flash size: 4MB
Compressed 15872 bytes to 10319...
Writing at 0x00001000... (100 %)
...

The software

Then you can control your vehicle with this Open Source Android app ESPHomeRC.