Abstract: An automated cartridge handling system or library (20, 20') for storing cartridges (22) of information storage media comprises a cartridge holder (26); a tape drive (30) movably mounted with respect to the cartridge holder; and, a transport system (40) for transporting the tape drive (30) in a drive transport path (42) between a unloaded position and a cartridge loaded position. The cartridges (22) remain stationary in the library while the tape drive is transported between the unloaded position and the cartridge loaded position. The cartridge holder library has a plurality of apertures (70) which receive cartridge holders or spines (80). To retain the cartridge (22) within the spine, each spine has resilient cartridge retaining fingers (100) formed in its interior cavity (90) for engaging a notch (104) on the cartridge. Each spine is provided with stabilization flanges (112) for stabilizing the cartridge.

Abstract: Methods and apparatus are provided for determining a servo offset value and a take-up reel velocity for imparting a desired linear velocity to tape in a helical scan recording system (20). The helical scan recorder system records information on a magnetic tape (22), the magnetic tape being transported between a supply reel (24) and a take-up reel (26) in the helical scan recorder through a tape path, which tape path includes at least a partial wrapping of the tape around a drum (30) of the helical scan recorder. The methods include moving the tape from the supply reel to the take-up reel whereby the tape travels a predetermined displacement; rewinding the tape by the tape extraction displacement and determining an angular rewind displacement of the take-up reel; and using the determined displacements to ascertain parameters including a desired velocity of the take-up reel.

Abstract: Methods of calibrating a helical scan recorder include transporting a storage media past a drum at a controlled linear velocity and recording tracks on the media using a write head. During a read-after-write operation, servo signals recorded on the track; are read. The servo signals from the tracks are used to determine an axial offset variance of the write head and a read head on the drum. In one mode, calibration is achieved for a first helical scan recorder which does not have a capstan, by installing a drum of the recorder in a second helical scan recorder, using the second recorder to record servo signals on two tracks, reading the servo signals from those two tracks, second recorder, using the servo signals to determine axial offset variance, and storing a value indicative of axial offset variance in a memory of the first recorder. The axial offset variance is used in a write splice operation and, in one mode, to determine linear velocity of the media.

Abstract: A capstanless helical scan recording system (14) comprises a supply reel (24); a take-up reel (26); and a media transport path (20) extending from the supply reel to the take-up reel. A drum (30) is positioned along the media transport path and has a read head (R1,R2) and a write head (W1,W2) mounted thereon for recording and reading information in helical stripes on the media. The take-up reel comprises a rotor assembly (60), a rotating hub assembly (70), and a gearing system. The rotor assembly includes a sun gear (80) which rotates at a first rotational speed. The rotating hub assembly rotates carries three planetary gears (160) and imparts a velocity to media transported in the media transport path. The gearing system meshes with the rotor assembly and with the hub assembly for causing the hub assembly to have a greater rotational speed than the rotor assembly. The gearing system preferably has a gear ratio on the order of about 8:1.

Abstract: A method of positioning the read/write head onto a desired data track in a multi-track recorder/player utilizes a plurality of registration stripes to find the central axis of a data track. In one embodiment, each registration stripe has associated with it a recorded identification pattern or tone which may be sensed and used for identification purposes. Then, based upon the read amplitude output of the read head, the appropriate edge of a registration stripe may be detected and, from there, the read/write head moved directly onto the desired data track without any subsequent open-loop movement. In an alternative embodiment, multiple edges are sensed and used in a calculation to determine the lateral displacement associated with the longitudinal centerline of a desired data track.

Abstract: A cartridge rack (60) houses a plurality of data storage cartridges (62) in an automated cartridge library (30). The rack comprises four sidewalls connected to define a rectangular perimeter of the cartridge rack, a backwall, and a plurality of ribs bridging opposite ones of the sidewalls, thereby forming a plurality of cartridge-receiving slots. Ramps (164, 120) are formed on an exterior surface of at least one of the side walls. An orientation fin (172) orthogonally extends from an underside of the backwall. At least one of the ramps (164) is a scalene triangularly-shaped crown ramp which is centrally located between opposing ones of two other of the sidewalls. Others of the ramps are feet ramps (120) formed on an opposite one of the sidewalls from the sidewall upon which the crown ramp (164) is formed. Apparatus is also provided mounting a data cartridge (60) in the cartridge library (30), including a rack mount (110) having a base plate (112).

Abstract: The cold boot data backup apparatus maintains an index of all data file activity on a computer system and stores copies of data files in a manner to enable a user to recreate the state of the computer system at any selected point in time. This apparatus automatically formats the computer system memory in response to a failure thereof and automatically restores the operating system, all application programs and every data file that is selected by the user to be monitored and preserved by this apparatus.

Abstract: A system and method is provided for controlling a brushless DC motor (100), the motor being of the type having a plurality of coils (25, 26, 27) and a switching amplifier coil driving circuit (25A, 26A, 27A) including a plurality of transistors (21, 22, 29, 30, 33, 34). Current application to the plurality of transistors is controlled to obtain, near a commutation point of the motor, a simultaneous rise in current applied to a first of the transistors and a fall in current applied to a second of the transistors. Controlling application of current to the plurality of transistors involves, for each of the transistors, generating a PWM gate drive signal by selectively switching between a nominal PWM signal and a constant signal. The selective switching is in response to a synthesized state signal, the synthesized state signal being generated to alternate variably between the two states in accordance with a desired ramping of current to the first and second transistors.

Abstract: A cartridge library (30) includes a magnetic tape drive (40), a cartridge magazine (36), and a gripper assembly (200) for moving a selected data cartridge (42) between the tape drive and the cartridge magazine. A bezel (70) of the magnetic tape drive has both a gripper-tripping projection (80) and two gripper-spreading cam members (90L, 90R) formed thereon. The two cam members (90L, 90R) are positionally formed to cause gripper fingers (220L, 220R) of the cartridge gripper to spread apart when the gripper assembly travels toward the bezel. The gripper-tripping projection is formed in a position to abut and snap finger linkages (222L, 222R) and close the gripper fingers of the gripper assembly at the time the gripper assembly is to engage a cartridge.

Abstract: Methods and apparatus are provided for determining a servo offset value and a take-up reel velocity for imparting a desired linear velocity to tape in a helical scan recording system (20). The helical scan recorder system records information on a magnetic tape (22), the magnetic tape being transported between a supply reel (24) and a take-up reel (26) in the helical scan recorder through a tape path, which tape path includes at least a partial wrapping of the tape around a drum (30) of the helical scan recorder. The methods include moving the tape from the supply reel to the take-up reel whereby the tape travels a predetermined displacement; rewinding the tape by the tape extraction displacement and determining an angular rewind displacement of the take-up reel; and using the determined displacements to ascertain parameters including a desired velocity of the take-up reel.

Abstract: In a helical scan system for recording information on a storage media in a series of helical tracks, servo information written on the tracks is used to control linear velocity of the media during a write operation. Helical scan system includes a rotating drum upon which write heads and read heads circumferentially are mounted. The write heads and the read heads are positioned on the drum so that during a drum revolution a read head reads servo information recorded on a track at least 1.5 track pitches upstream from the most recently recorded track. A servo controller analyzes, during the recording operation, servo information read back by the read head subsequent to recording thereof by write head. Servo controller uses the servo information read by the read head to generate a signal for application to a motor for controlling linear velocity of the media during the write operation.

Abstract: The data storage and protection apparatus maintains an index of all data file activity on a computer system and stores copies of data files in a manner to enable a user to recreate the state of the computer system at any selected point in time. A data file monitor intercepts all communication between application programs and the file system to obtain data file status and activity information. This information is used to identify data files which are transmitted to a data file backup media for storage along with directory information that identifies the stored files to enable the system to later locate and retrieve data files that were stored on the backup media.

Abstract: An automated library (30) handles a plurality of data storage units (e.g., data cartridges) stored therein. The library comprises an octagonal drum-like member (34) mounted above a library frame (32). The drum (34) has a plurality of faces on an exterior periphery thereof, each for selectively accommodating a cartridge rack (62). Each face of the drum has a rack mount (110) selectively attachable thereto. The library further comprises a rack (38) for accommodating a plurality of modular I/O drive-containing drawers (64). A picker device (80) engages and transports data cartridges between drives (320), an active rack (60), and an entry/exit port transport (500). The entry/exit transport device (500) transports a selected cartridge between a predetermined position in the cabinet and the entry/exit port (100). The entry/exit transport device (500) is both rotatable and extensible. A picker move method and library inventory method are also provided.

Abstract: A capstanless helical scan recording system (14) comprises a supply reel (24); a take-up reel (26); and a media transport path (20) extending from the supply reel to the take-up reel. A drum (30) is positioned along the media transport path and has a read head (R1,R2) and a write head (W1,W2) mounted thereon for recording and reading information in helical stripes on the media. The take-up reel comprises a rotor assembly (60), a rotating hub assembly (70), and a gearing system. The rotor assembly includes a sun gear (80) which rotates at a first rotational speed. The rotating hub assembly rotates carries three planetary gears (160) and imparts a velocity to media transported in the media transport path. The gearing system meshes with the rotor assembly and with the hub assembly for causing the hub assembly to have a greater rotational speed than the rotor assembly. The gearing system preferably has a gear ratio on the order of about 8:1.

Abstract: In a multi-track magnetic tape recorder/player of the type used for data storage and retrieval, with at least one read head and one write head, both being displaceable laterally relative to the direction of tape travel, and a memory to store values representative of those lateral displacements with respect to a reference position, a method for exact positioning of the read head onto previously written data tracks. In the preferred method, the write head is used to record (or erase) a longitudinal stripe along the tape, and the read head is used to find one or more edges of the stripe relative to a reference position. The displacements used to write the stripes and the displacements associated with the edges are compared to generate an offset correction factor used for subsequent head positioning.

Abstract: A magnetic tape drive system (20) records a directory block (CL) at a predetermined position on tape (22), and preferably at the beginning of tape. The directory includes, for each recorded track on tape (22), a data block number of the data block recorded at an end of the track. Preferably a plurality of copies of directory block (CL) are recorded, preferably in reverse direction. Upon receipt of a command to locate a target data block recorded on tape (22), a processor (102) directs a transport controller (82) to position a read element (30R) at the predetermined position on tape (22) for reading the directory. The read element reads the directory from tape (22).

Abstract: A helical scan system (10) determines whether a medium is a non-native formatted medium and controls operating parameters (e.g., tape speed) so that a non-native formatted medium can be read without resort to embedded servo information in the non-native medium. The helical scan system reads the medium in a manner to obtain format-indicative information therefrom, and then determines whether the medium is non-native formatted. If the medium is non-native formatted, a controller determines operating parameters required by the system to read the non-native formatted medium and generates signals corresponding to the required operating parameters. The medium is preferably read in a slow speed mode in order to obtain format-indicative information therefrom, and block header information obtained from the medium is analyzed to determine whether the medium is non-native formatted.

Abstract: An automated library (30) for handling a plurality of data storage units comprises a frame (32), an I/O drive (320); a unit engagement device (80) which transports data storage units between the drive and the storage receptacle. A cabinet substantially encloses the frame and has an entry/exit port (100) formed therein. The library is further provided with an entry/exit transport device (500) which pivots 90 degrees about an axis perpendicular to a unit orientation plane to transport a selected data storage unit between the entry/exit port and a predetermined position in the cabinet. The entry/exit transport device has a cartridge engagement portion with two edges (574, 576), a first of the edges being configured to load/unload the selected data storage unit at the entry/exit port and a second of the edges being configured to load/unload the selected data storage cartridge at the predetermined position. The first and second edges are orthogonal to one another in the entry/exit transport plane.

Abstract: A picker mechanism (80) selectively grips and transports a data storage cartridge (62) in an automated library (30). The picker mechanism (80) has a picker frame (400) comprised of two half shell members (402, 404). Substantially all active elements of the picker are mounted to a base half shell (402) over which a cover half shell (404) mates for enclosing substantially all active picker elements. The active picker elements include a pair of gripper fingers (406) pivotally mounted to the picker frame. Each gripper finger (406) has a portion thereof configured to engage a data storage cartridge. The picker frame also carries a displacement path (e.g., leadscrew 418) along which a carriage member (e.g., leadscrew nut 426) travels. A motor (414) is provided for driving the carriage member (426) along the displacement path. A pair of biasing springs (432), one for each gripper finger (406), are provided for biasing the gripper fingers in a direction toward the displacement path.

Abstract: A system (20) for controlling deceleration of a motor (22) during an abrupt power-off condition includes a processor (40), a motor control circuit (50), and a secondary power source (70). During normal power-on operation and based on currently prevailing operation parameters, processor (40) routinely generates a contingent motor-governing deceleration signal for potential use in governing motor (22) should the power-off condition occur. In response to the occurrence of a power-off condition, motor control circuit (50) controls motor (22) in accordance with the contingent motor-governing deceleration signal to achieve orderly deceleration. Secondary power supply circuit (70) provides power to motor control circuit (50) during the power-off condition.