Patent ID: 8694153

Claim:
A method of operating a storage section ( 14 ) of a laboratory system, the storage section ( 14 ) comprising (a) a plurality of shelves ( 110 ) for storing a plurality of sample tube racks, the shelves including a top shelf and a bottom shelf, the top and bottom shelves having a first end and an opposite second end, and (b) a robotic transfer system ( 510 ) for loading sample tube racks into the storage section ( 14 ) and retrieving sample tube racks from the storing section ( 14 ), the method comprising the following steps: moving the robotic transfer system ( 510 ) along the top shelf or the bottom shelf from the first end thereof to the opposite second end thereof; identifying a plurality of markings defining a plurality of individual storage rack end positions; measuring a plurality of distances between the individual storage rack end positions defined by such markings; and storing absolute coordinates of the individual storage rack end positions from the identified markings and measured distances.