LED-Following Car

hardware logic structure looks as follows:


In our project, the phototransistors sent their outputs to the ATMEL Mega644 microcontroller. The MCU then calculates which motors should move based on the phototransistors and sends a signal to the optoisolators telling which motors to turn on. Depending on which optoisolator is turned on, the motor control will tell which motor to move. We used optoisolators to separate the MCU from the motor circuitry. Optoisolators isolate the LED side of the circuit from the phototransistor side of the circuit, ideally protecting the MCU from any unknown outputs from the motor controller.