The car is made to follow a non-predetermined path by following a line against a luminance contrasting surface that is detected by an array of sensors.
An Atmel AVR8515 microcontroller is used by the car in order to have a complete control of the car by controlling the drive and steering servos. The microcontroller steers the car accordingly as it senses the position of the line in reference to the car. The wheel rotation is detected by a 6th light sensor which maintains constant speed. The data from the wheel is obtained by a digital feedback algorithm as the desired speed is maintained by adjusting the PWM signal to the motor.
The light reflectance is detected by the sensors and the floor is illuminated by each of 5-arrayed infrared LED. An output of 0V or 5V is the result of converting the output of the detectors. A higher reflectance surface indicates white line due to low output while a black line below a sensor is indicated by a high output.
A LED-sensor pair is mounted facing the wheel which detects the speed of the car. It also detects the position of wheel.