Abstract: An apparatus for controlling an electric motor is provided. A plurality of switches is provided for controlling a direction of current through motor coils of the electric motor. A brushless motor control circuit is connected to each of the plurality of switches. Responsive to a request to adjust one of an angular velocity and an angular acceleration of the electric motor, the plurality of switches are activated to place the motor coils in a predetermined configuration to maximize torque or reduce a total back electromotive force (BEMF) from the motor coils.

Abstract: A calculation function, which optimizes a dynamic reconfiguration-switching of motor windings between winding-configurations, is dynamically configured. Acceleration is traded off in favor of higher velocity upon detecting the electric motor is at an optimal angular-velocity for switching to an optimal lower torque constant and voltage constant. The total back electromotive force (BEMF) is prohibited from inhibiting further acceleration to a higher angular-velocity.

Abstract: Dynamic reconfiguration-switching of motor windings is optimized between winding-configurations. Acceleration is traded off in favor of higher velocity upon detecting a brushless DC motor is at an optimal angular-velocity for switching to an optimal lower torque constant and voltage constant. The total back electromotive force (BEMF) is prohibited from inhibiting further acceleration to a higher angular-velocity.

Abstract: Dynamic reconfiguration-switching of motor windings in an electric motor in an electric vehicle is optimized between winding-configurations. Acceleration is traded off in favor of higher velocity upon detecting the electric motor in the electric vehicle is at an optimal angular-velocity for switching to an optimal lower torque constant and voltage constant. The total back electromotive force (BEMF) is prohibited from inhibiting further acceleration to a higher angular-velocity.

Abstract: Dynamic reconfiguration-switching of motor windings is optimized between winding-configurations. Acceleration is traded off in favor of higher velocity upon detecting a tape storage drive is at an optimal angular-velocity for switching to an optimal lower torque constant and voltage constant. The total back electromotive force (BEMF) is prohibited from inhibiting further acceleration to a higher angular-velocity.

Abstract: Dynamic reconfiguration-switching of motor windings is optimized between winding-configurations. Acceleration is traded off in favor of higher velocity upon detecting an electric motor is at an optimal angular-velocity for switching to an optimal lower torque constant and voltage constant. The total back electromotive force (BEMF) is prohibited from inhibiting further acceleration to a higher angular-velocity.

Abstract: Tape media life is increased by dynamically controlling a turn around point (TAP) on the tape media for either an end of a tape wrap or a directional change from a first longitudinal position tape section to a second longitudinal position tape section for reducing damage to the tape media caused by debris by monitoring the TAP for all tape media motion and adjusting tape deceleration for maintaining the TAP to be located at the second longitudinal position tape section.

Abstract: A tape movement constraint for a tape drive system, comprises a tiltable tape roller bearing having a grooved surface adapted to contact and engage a surface of the tape as the roller barrel rotates, and an actuator adapted to pivot the roller bearing surface when the actuator is actuated, to control the lateral position of a tape. In operation, in one embodiment, a roller barrel of the tiltable roller bearing is biased in a first position on a pivot axis, using magnetic attraction between a movable magnet and a return path structure of magnetically permeable material. The roller barrel is pivoted on the pivot axis by conducting current through a fixed coil to generate a magnetic field which is conducted by the return path structure to interact with the magnetic field of the magnet. Other embodiments are described and claimed.

Abstract: A tape movement constraint for a tape drive system, comprises a tiltable tape roller bearing having a grooved surface adapted to contact and engage a surface of the tape as the roller barrel rotates, and an actuator adapted to pivot the roller bearing surface when the actuator is actuated, to control the lateral position of a tape. In operation, in one embodiment, a roller barrel of the tiltable roller bearing is biased in a first position on a pivot axis, using magnetic attraction between a movable magnet and a return path structure of magnetically permeable material. The roller barrel is pivoted on the pivot axis by conducting current through a fixed coil to generate a magnetic field which is conducted by the return path structure to interact with the magnetic field of the magnet. Other embodiments are described and claimed.

Abstract: Described are embodiments of an invention for customizing the range of acceptable write conditions to a tape of a tape cartridge that contracts or expands laterally based on environmental conditions. The tape drive utilizes servo information to determine if the tape has expanded or contracted from the nominal dimension and to determine the magnitude of the expansion or contraction. In the case of expansion, the magnitude of the determined expansion and the stored maximum amount of contraction must be below a predetermined threshold value to allow a write. In the case of contraction, the magnitude of the determined contraction and the stored magnitude of expansion must be below the same predetermined threshold value to allow a write. If the determined magnitude of contraction or expansion is greater than the stored magnitude of contraction or expansion, respectively, then the new extreme is stored.

Abstract: Tape media life is increased by dynamically controlling a turn around point (TAP) on the tape media for either an end of a tape wrap or a directional change from a first longitudinal position tape section to a second longitudinal position tape section for reducing damage to the tape media caused by debris by monitoring the TAP for all tape media motion and adjusting tape deceleration for maintaining the TAP to be located at the second longitudinal position tape section.

Abstract: A magnetic tape drive has a drive system to move a magnetic tape longitudinally; servo head(s) for reading servo band information from a magnetic tape as the magnetic tape is moved longitudinally; a magnetic tape read write head configured to read and to write the magnetic tape, having a data write width (w) greater than a normal shingled track pitch width (p) of the magnetic tape; an actuator system for positioning the read write head laterally; and a control. The magnetic tape drive stores an overwrite erase format of non-shingled track pitch longitudinal pattern(s) whose pitch is greater than the normal shingled track pitch width (p); and, the control, in response to activation of overwrite erasure of the tape drive, operates the actuator system and the magnetic tape read write head to write non-data to magnetic tape in the stored overwrite erase format.

Abstract: An apparatus for controlling an electric motor is provided. A plurality of switches is provided for controlling a direction of current through motor coils of the electric motor. A brushless motor control circuit is connected to each of the plurality of switches. Responsive to a request to adjust one of an angular velocity and an angular acceleration of the electric motor, the plurality of switches are activated to place the motor coils in a predetermined configuration to maximize torque or reduce a total back electromotive force (BEMF) from the motor coils.

Abstract: In accordance with the present invention, a method of operating a magnetic tape drive, a magnetic tape drive and a servo control system are provided for obtaining and maintaining velocity control in a magnetic tape drive. In one embodiment, a method is provided for operating a magnetic tape drive. The tape drive includes a plurality of DC motors, and each DC motor has a plurality of Hall sensors. The DC motors are under the control of a servo system which is configured to read location information from the magnetic tape, and compute a primary tape velocity from the location information, and sense a secondary and tertiary velocity signal and compute a tape velocity based on one of the sensed secondary velocity signal and tertiary velocity. The method includes detecting if the primary velocity location information is available. In response to detecting that the primary velocity location information is available the primary velocity is employed to control the servo system.

Abstract: Dynamic reconfiguration-switching of motor windings is optimized between winding-configurations. Acceleration is traded off in favor of higher velocity upon detecting an electric motor is at an optimal angular-velocity for switching to an optimal lower torque constant and voltage constant. The total back electromotive force (BEMF) is prohibited from inhibiting further acceleration to a higher angular-velocity.

Abstract: A tape movement constraint for a tape drive system, comprises a tiltable tape roller bearing having a grooved surface adapted to contact and engage a surface of the tape as the roller barrel rotates, and an actuator adapted to pivot the roller bearing surface when the actuator is actuated, to control the lateral position of a tape. In operation, in one embodiment, a roller barrel of the tiltable roller bearing is biased in a first position on a pivot axis, using magnetic attraction between a movable magnet and a return path structure of magnetically permeable material. The roller barrel is pivoted on the pivot axis by conducting current through a fixed coil to generate a magnetic field which is conducted by the return path structure to interact with the magnetic field of the magnet. Other embodiments are described and claimed.

Abstract: A tape movement constraint for a tape drive system, comprises a tiltable tape roller bearing having a grooved surface adapted to contact and engage a surface of the tape as the roller barrel rotates, and an actuator adapted to pivot the roller bearing surface when the actuator is actuated, to control the lateral position of a tape. In operation, in one embodiment, a roller barrel of the tiltable roller bearing is biased in a first position on a pivot axis, using magnetic attraction between a movable magnet and a return path structure of magnetically permeable material. The roller barrel is pivoted on the pivot axis by conducting current through a fixed coil to generate a magnetic field which is conducted by the return path structure to interact with the magnetic field of the magnet. Other embodiments are described and claimed.

Abstract: Dynamic reconfiguration-switching of motor windings in an electric motor in an electric vehicle is optimized between winding-configurations. Acceleration is traded off in favor of higher velocity upon detecting the electric motor in the electric vehicle is at an optimal angular-velocity for switching to an optimal lower torque constant and voltage constant. The total back electromotive force (BEMF) is prohibited from inhibiting further acceleration to a higher angular-velocity.

Abstract: Dynamic reconfiguration-switching of motor windings is optimized between winding-configurations. Acceleration is traded off in favor of higher velocity upon detecting a brushless DC motor is at an optimal angular-velocity for switching to an optimal lower torque constant and voltage constant. The total back electromotive force (BEMF) is prohibited from inhibiting further acceleration to a higher angular-velocity.

Abstract: A calculation function, which optimizes a dynamic reconfiguration-switching of motor windings between winding-configurations, is dynamically configured. Acceleration is traded off in favor of higher velocity upon detecting the electric motor is at an optimal angular-velocity for switching to an optimal lower torque constant and voltage constant. The total back electromotive force (BEMF) is prohibited from inhibiting further acceleration to a higher angular-velocity.