Abstract: The present invention is a mobile storage system that includes a number of mobile storage units movably disposed with respect to one another and including a logic system. A signal from a motion control actuator on a mobile storage unit which is to move where an aisle is desired directs a run signal to at least one unit to cause one or multiple units to be driven successively away from a desired aisle. If multiple units are moved together, a motion control actuator on the unit adjacent the closing aisle is operated to move the actuated unit and the other units. The logic system remembers and maintains each new open aisle width and closed aisle width after the termination of a particular movement.