A system and method for exchanging tape cartridges between two automated tape
cartridge
libraries. A carriage assembly carries cartridges back and forth between the libraries.
The carriage assembly includes a cartridge transport cell, has a vertical axis,
and cooperates with pass through ports in the libraries for providing access to
tape cartridge storage cells in the libraries. A guide structure extends between
the libraries for supporting the carriage assembly. The guide structure defines
a linear path and has first and second sides substantially parallel to the linear
path which define an envelope. The carriage assembly is driven along the guide
structure, and automatically rotates about the substantially vertical axis. The
cartridge transport cell is accessible by robotic devices in the libraries when
the carriage assembly is aligned with the pass through ports. The carriage assembly
rotates substantially within the envelope as it is driven along the guide structure.