HP 20/700 - Manual (Page 17)

16 Tape Library Components Chapter 1
Robot
The robot moves cartridges between storage cells, between cells and tape
drives, and between the CAP and cells. The robot consists of the Z-column
assembly (vertical motion), the theta mechanism (lateral motion), and the
hand-camera assembly. Figure 2 on page 17 shows these robot components.
The Z-column assembly contains a Z-column and Z-carriage. The Z-column
attaches to the floor and ceiling of the tape library. The Z-column can rotate
almost 360 degrees to enable access to all the cells in the tape library.
The hand-camera assembly, which is attached to the Z-carriage, grasps and
releases cartridges. The Z-carriage moves the hand up and down the Z-column
to storage cells, drives, or the CAP.
The camera, which is on the hand, is active only during a library audit. An
audit occurs when you:
■ Power-on the tape library.
■ Open and close the left access library door.
■ Make a request from your backup application software to audit the tape
library.
During an audit, the camera reads the location and volume serial number
(VOLSER) of each cartridge in the storage cells and reserved cells. Since this
information is stored in the library’s memory, the library does not rely on the
camera to read cartridge locations or VOLSERs during mount and dismount
operations.