A few questions about the purpose of structures seen in STAR TREK-style dry docks: Whether it is the laticework structure of the first dock seen in TMP, or subsequent space stations or other dock-like structures, or even fan-made designs, why do these docks feature arms and laticework that either partially or completely envelops the sides of the ship in dock? What purpose do these "cage" like structures serve? Does the arm / cage serve as a tangible boundary for zero-g maneuvers of spacesuited personnel and free-floating equipment and materiel? Do these structures serve as a platform for containment forcefields to keep authorized personnel, equipment and materiel "in" and unauthorized things (like micrometeoroids or intruders) "out"? Has anyone ever tried to figure out how the docks themselves are structured? Do these docks maintain crew quarters or other habitats for dockyard personnel to live/operate from? Has anyone ever drawn a blueprint of a drydock?