Abstract: In a data storage library having a plurality of cells for use in housing media cartridges, each cell having a location in the library, the library further having a moveable robot for retrieving the cartridges from the cells, a system and method for aligning the robot with a cell. A target in the library has a first, second and third portion, each with a different reflectivity. A source on the robot directs a beam toward the target portions, and the reflected beam has an intensity based on the reflectivity of the respective target portion. A sensor on the robot senses the reflected beam and generates a signal representing the reflected beam intensity. A controller receives the signal, determines a location of the target in the library relative to the robot based on changes in the reflected beam intensity, and generates a control signal for aligning the robot with the cell based on a known relationship between the target location and the cell.

Abstract: A method and apparatus is provided for auditing cartridges and empty cells in a storage library system including a plurality of cells for storing cartridges and further including a robotically actuated hand assembly. A line-scan camera is secured to the hand assembly, and a visible pattern is positioned within each cell such that the visible pattern is readable by the line-scan camera when the line-scan camera is moved to a position adjacent the particular cell if the cell is empty. The visible pattern is positioned such that the presence of a cartridge within the particular cell would prevent viewing of the visible pattern within the cell by the line-scan camera. The line-scan camera is operated in a manner to search for the visible pattern within each cell for auditing numbers of cartridges and empty cells in the storage library system.

Abstract: An apparatus for latching and ejecting cartridges from a cartridge tape drive in a storage library system includes a robotically actuated hand assembly. The apparatus comprises a pin extending from the hand assembly and a rotatable lever extending from the cartridge tape drive. The rotatable lever is pivotable between a first position in which the cartridge is locked in the tape drive and a second position in which the cartridge is ejected from the tape drive. The pin is operative to engage the rotatable lever for pivoting the lever between the first and second positions when the hand assembly is robotically actuated. A visible pattern is applied to the rotatable rod and offset from the axis of rotation of the rod such that the pattern appears to move into and out of alignment with the camera target as viewed by a line-scan camera when the rod rotates between the first and second positions. Accordingly, the status of the tape drive may be easily attained.