Temperature and humidity measurements are a nice addition ... He decided to take an in-depth look at the DHT11 sensor; which you can get your hands on for under $3 if you know where to look.

Thus, the car adds a DHT11 temperature and humidity sensor, along with a BMP280 air ... Small DC motors at each wheel are driven via a DFRobot quad-motor shield. With the built-in screen, the ...