Remotely operated vehicle for a storage system

A remotely operated vehicle for retrieving and/or replacing items from a storage system comprising a framework structure having a track system at an upper level of the framework structure upon which the vehicle travels, the track system comprising a plurality of tracks arranged in a first direction and a plurality of tracks arranged in a second direction perpendicular to the first direction, whereby intersecting tracks define cells arranged in a grid pattern, through which cells a lifting device of the vehicle may access items stored in the storage system, the vehicle comprising

• a vehicle body or framework displaying a cavity arranged centrally within the vehicle body or framework for receiving and holding an item from the storage system,
• the lifting device comprising a gripping member attached to an elongated lowering and raising mechanism arranged for lowering the gripping member through a cell to access a stored item, the gripping member arranged to grip the item and the elongated mechanism being arranged to lift the item into the cavity,
• two sets of wheels, a first set of wheels arranged to travel along the tracks in the first direction and a second set of wheels arranged to travel along the tracks in the second direction, and
• a displacement arrangement comprising a displacement motor
• wherein the displacement motor is configured to provide power or force to vertically displace at least one of the first set of wheels and the second set of wheels between a displaced state where the set of wheels is displaced away from the tracks during use, and a non-displaced state where the set of wheels is in contact with the tracks during use, thereby changing the direction of travel of the vehicle, and
• wherein the vehicle body or framework occupies at most a space of a single cell and the tracks defining the cell during a retrieval or replacement operation.