The work has started off by taking out the original radio and motor drive modules and the antenna from the car. We were left with two motors, one for steering and one for acceleration, and the plan was to rebuild the whole architecture using Arduinos. We succeeded and the motors are now driven with a powerful H-bridge module (L298n) and the wireless connection is handled by two nRF24l01 antennas. The arduino and the motors are both powered from the original 6V battery pack (4xAA).
The onboard Arduino Nano receives wireless messages from an Arduino UNO connected to a Macbook Pro. This laptop runs a Node.js server that has two main two tasks in this workflow: firstly it sets up a realtime connection with the browser using web sockets and the socket.io node module, secondly it passes on this control data to the Arduino UNO through the USB port. Serial messages can very easily be sent through the port with the serial node module. Essentially this server is the link between the browser and the Arduino UNO.
We put together a quick, one and a half minute video showing the build process and the first test drives.
This project is not yet finished. We are planning to install an onboard, wireless camera that will be streamed to a monitor in front of the racing wheel for a true simulator experience, like if you were sitting in the seats of the toy car. Adding a pair of red break lights and white headlamps, two temperature sensor for the motors or a buzzer for horn is also in the plan.