The train operator ( driver ) closes the train doors and presses a pair of `` start '' buttons . If the way ahead is clear , the ATO drives the train at a safe speed to the next station and stops there . The line is equipped with an Automatic Train Operation system ( ATO ) ; the train operator ( driver ) closes the train doors and presses a pair of `` start '' buttons , and if the way ahead is clear , the ATO drives the train at a safe speed to the next station and stops it there .