An incubator for storing micro-plates or micro-tubes comprises a handling robot positioned between shelves or drawers containing micro-titer plates or other containers useful for biological based reactions. The advantages of this configuration are the ultimate compactness of the system and increased speed or reliability achieved with more than one robot being able to access the same plate or tube. Alternative embodiments standardize the spacing and configuration of a robot track and a shelf track such that a shelf and a robot are interchangeable in a track.