Vehicle that is not bound to rails

The vehicle (30) has a detecting unit (50) to detect a relative position (R) of a current collector (40) to contact wires (11). A steering assistance system (33) is arranged to perform automatic steering of vehicle based on detected relative position. A position determining system (60) is provided to determine a current position (P3) of vehicle on a lane (20). A database (70) is stored with a contact wire position (P1) of contact wires along lane. The distance between determined current vehicle position and the contact wire position is calculated.