G11B5/55

Magnetic tape device and head tracking servo method

The magnetic tape device includes: a magnetic tape; and a servo head, in which a magnetic tape transportation speed of the magnetic tape device is equal to or lower than 18 m/sec, the servo head is a magnetic head including a tunnel magnetoresistance effect type element as a servo pattern reading element, the magnetic tape includes a non-magnetic support, and a magnetic layer including ferromagnetic powder and a binding agent on the non-magnetic support, the magnetic layer includes a servo pattern, and a coefficient of friction measured regarding a base portion of a surface of the magnetic layer is equal to or smaller than 0.30.

Interlaced magnetic recording in with multiple independent-actuators having respective independent heads

A first set of bottom tracks is written via a first head that is moved via a first actuator over a surface of a disk. A second set of top tracks interlaced between and partially overlapping the bottom tracks via a second head that is moved via a second actuator over the surface of the disk independently of the first actuator and first head.

Characterization of nonlinearity in servo patterns

In one general embodiment, a method includes applying a static head skew to a magnetic tape head, positioning the first reader at a first y-position relative to a servo pattern in a servo band, measuring y-positions of the second reader relative to the servo pattern in the servo band while the first reader is at the first y-position, and averaging the measured y-positions. The method further includes repeating the following process several times: moving the first reader to a next y-position, measuring y-positions of the second reader while the first reader is at the next y-position, and averaging the y-positions measured by the second reader while the first reader is at the next y-position. The method further includes calculating a unique nonlinearity value of the servo pattern in the servo band for each of the average y-position values, and storing and/or outputting the calculated nonlinearity values.

Carriage device

A carriage device includes a first guide member and a second guide member for supporting a carriage with a head mounted thereon at two separate positions and guiding reciprocation of the carriage, a first adjustment unit configured to adjust a height of the carriage relative to the first guide member through movement of the carriage, and a second adjustment unit configured to adjust a height of the carriage relative to the second guide member through the movement of the carriage. The carriage device can sequentially perform a first operation of changing the height of the carriage by the first adjustment unit and a second operation of changing the height of the carriage by the second adjustment unit.

Multi-Layer PZT Microactuator Having A Poled But Inactive PZT Constraining Layer
20190214042 · 2019-07-11 ·

A multi-layer piezoelectric microactuator assembly has at least one poled and active piezoelectric layer and one poled but inactive piezoelectric layer. The poled but inactive layer acts as a constraining layer in resisting expansion or contract of the first piezoelectric layer thereby reducing or eliminating bending of the assembly as installed in an environment, thereby increasing the effective stroke length of the assembly. Poling only a single layer would induce stresses into the device; hence, polling both piezoelectric layers even though only one layer will be active in use reduces stresses in the device and therefore increases reliability.

Data storage device configuring a write inhibit shock threshold for multiple actuators

A data storage device is disclosed comprising a first actuator configured to actuate a first head over a first disk comprising a first plurality of tracks defined by first servo sectors, and a second actuator configured to actuate a second head over a second disk comprising a second plurality of tracks defined by second servo sectors. The first actuator is controlled based on the first servo sectors in order to first write data to the first disk, and the second actuator is controlled based on the second servo sectors in order to second write data to the second disk. The first writing is inhibited when a shock signal generated based on a shock sensor exceeds a first shock threshold, and the second writing is inhibited when the shock signal exceeds a second shock threshold different from the first shock threshold.

Multilayer disk drive motors having out-of-plane bending

Various embodiments concern a gimbaled flexure having a dual stage actuation structure. The flexure comprises a gimbal on which a motor is mounted. The motor comprises a first and second terminals and a plurality of actuator layers formed from a piezoelectric material. The plurality of actuator layers comprise serially stacked first, second, and third actuator layers. The plurality of actuator layers are respectively poled and connected to the first and second terminals such that both of the first and second actuator layers expand while the third actuator layer contracts in response to application of a signal across the first and second terminals. The differential motion of the plurality of layers in the motor cause the motor to curl about the contracting third actuator layer. The curling motion causes a portion of the flexure to preferentially curl.

APPARATUS, SYSTEM, AND METHOD FOR PREVENTING SHOCK-INDUCED HARD DRIVE DAMAGE
20190198060 · 2019-06-27 ·

A shack-sensor apparatus may include a sensor configured to detect a positional state of a hard-drive drawer. The shock-sensor apparatus may also include a mounting component coupled to the sensor and configured to mount the sensor in a location to monitor the positional state of the hard-drive drawer. In addition, the shock-sensor apparatus may include a computing module, electronically coupled to the sensor, that analyzes sensor data provided by the sensor to predict a shock event of the hard-drive drawer and send, in response to predicting the shock event, a signal to at least one hard drive in the hard-drive drawer to prevent damage to the hard drive. Various other apparatuses, systems, and methods are also disclosed.

LINEARITY DETECTING METHOD AND DEVICE FOR SERVO POSITION SENSOR, AND ROBOT WITH THE SAME
20190198048 · 2019-06-27 ·

The present disclosure provides a linearity detecting method and apparatus for a servo position sensor, and a robot with the same. The method includes: collecting and saving m output angle of the servo under test; analyzing the output angle to obtain a relationship curve of angle and time of the servo under test to rotate for one turn; extracting angle information of a starting point to an ending point of the output angle corresponding to the position sensor in the servo under test based on the relationship curve of angle and time to obtain valid angle data; and determining whether the output angle corresponding to the position sensor is linear based on the valid angle data. The present disclosure can solve the problem that an external sensor and a fixture are required when detecting the linearity of the sensor which causes complicated operation, high detection cost, and low detection efficiency.

Reducing vibration transmission in a dual actuator disk drive utilizing a single pivot shaft

An actuator pivot shaft assembly for a multi-actuator data storage device may include one or more annular grooves extending radially inward from an outer surface of the pivot shaft, thereby desirably weakening or structurally decoupling the shaft between the actuators, to assist with inhibiting transmission of vibration between the actuators during operation. The shaft assembly may further include an elastomeric damper positioned within the annular groove(s), to damp transmission of vibrational forces between the actuators through the shared shaft.