A Lego nxt robot controlled by a windows mobile application or by a pc apllication, nxt remote. The robot is connected to the pc or mobile via bluetooth. When the robot hears the work "πάρκαρε" the ultrasonic sensor turns right and checks if the distance is bigger than 30cm.
Simultaneously the Lego nxt robot is controlled by bluetooth application moving it forward,backward,left,right. When the ultrasonic sensor detects a distance bigger than 30cm, the robot goes forward and then backward and right to park. ...