Controlling the car is actually controlling the motor of the car. Generally, it is controlled by PWM signal. For example, if the car moves forward, it will output a forward PWM signal and a reverse PWM signal. Adjusting the duty cycle of PWM signal can change the speed of the motor, thus changing the speed of the car. In addition, turning requires signals provided by sensors. When programming, first understand the motor data of the car, and then capture the signal of the sensor.