Abstract: Methods and systems for self-servowriting a data storage medium are disclosed, including servoing to propagation bursts of a propagation pattern located in tracks other than an immediately preceding track. Reference levels used to position a recording head are accordingly kept in a usable dynamic range necessary to keep servo track spacing constant across the medium. The methods and systems are disclosed in connection with a rotary actuator having spaced read and write heads. Similar methods are disclosed for writing trigger or timing bursts of the propagation pattern.

Abstract: Methods and systems for self-servowriting a data storage medium are disclosed, including servoing to propagation bursts of a propagation pattern located in tracks other than an immediately preceding track. Reference levels used to position a recording head are accordingly kept in a usable dynamic range necessary to keep servo track spacing constant across the medium. The methods and systems are disclosed in connection with a rotary actuator having spaced read and write heads. Similar methods are disclosed for writing trigger or timing bursts of the propagation pattern.

Abstract: Improvements in placement of timing patterns in self-servowriting include detecting and correcting for media defects. A detector is used to detect whether a trigger pattern is within an expected location on the storage medium. If the trigger pattern is not detected, then a physical defect may be present. Thus, in one example, a false trigger pattern is generated. Additionally, a determination is made as to whether a trigger pattern is within an expected trigger pattern region. When the trigger pattern is not within the expected range, then a valid interval window may be modified to adjust the expected trigger pattern region.

Abstract: Improvements in placement of timing patterns in self-servowriting include correcting for random errors. Random errors may be caused by variations in disk velocity and therefore, one technique for correcting for random errors includes reducing velocity jitter. Additionally, random errors can be corrected by improving interval control during the propagation of trigger patterns used in writing timing information on storage media. Further, random errors, in the writing of timing information, can be corrected during a single revolution of the storage media. This eliminates additional rotations, thereby providing a large capital cost savings.

Abstract: Improvements in placement of timing patterns in self-servowriting include correcting for random errors. Random errors may be caused by variations in disk velocity and therefore, one technique for correcting for random errors includes reducing velocity jitter. Additionally, random errors can be corrected by improving interval control during the propagation of trigger patterns used in writing timing information on storage media. Further, random errors, in the writing of timing information, can be corrected during a single revolution of the storage media. This eliminates additional rotations, thereby providing a large capital cost savings.

Abstract: Methods and systems for self-servowriting a data storage medium are disclosed, including servoing to propagation bursts of a propagation pattern located in tracks other than an immediately preceding track. Reference levels used to position a recording head are accordingly kept in a usable dynamic range necessary to keep servo track spacing constant across the medium. The methods and systems are disclosed in connection with a rotary actuator having spaced read and write heads. Similar methods are disclosed for writing trigger or timing bursts of the propagation pattern.

Abstract: Methods and systems for self-servowriting a data storage medium are disclosed, including servoing to propagation bursts of a propagation pattern located in tracks other than an immediately preceding track. Reference levels used to position a recording head are accordingly kept in a usable dynamic range necessary to keep servo track spacing constant across the medium. The methods and systems are disclosed in connection with a rotary actuator having spaced read and write heads. Similar methods are disclosed for writing trigger or timing bursts of the propagation pattern.

Abstract: An accurate and time-efficient method and system for self-servowriting wherein at least one reference value used to position the transducer is updated for some, but not all, of the tracks to be written. The reference value(s) is dependent upon a predefined indicium of transducer position, such as the amplitude of the readback signal obtained from a written track when the transducer is positioned on the track. In a first embodiment, updating of the reference value(s) is performed at every Nth track written, where N is a fixed number or range of numbers determined by an expected track-to-track variation of the indicium. The servowriting system may be designed to dynamically increase or decrease N during servowriting in response to actual variations in the indicium. According to a second embodiment, updating is only performed when needed, e.g. when the variation of the measured indicium between two written tracks (not necessarily adjacent tracks) exceeds a predefined threshold value.

Abstract: A self-servowriting system and method for implementation in a storage device such as a disk drive are described. Two problems associated with self-propagation are greater mechanical disturbances and the growth of errors during many thousands of servowriting steps. Error growth is attributable to the special properties of servo loops as applied to a repetitive self-propagation process. Greater resistance to mechanical disturbances and reduction in error growth are achieved, in part, by adjusting a step amplification factor, S, at the initiation of servowriting to within desired parameters. However, S is known to vary with movement of the head in a direction transverse to the direction of the tracks. This problem is addressed by the present invention, wherein S is determined at a plurality of transverse transducer positions. S is dependent upon the closed loop response of the servo system C and upon a set of step-to-step correction factors f.

Abstract: Methods and systems for self-servowriting a data storage medium are disclosed, including servoing to propagation bursts of a propagation pattern located in tracks other than an immediately preceding track. Reference levels used to position a recording head are accordingly kept in a usable dynamic range necessary to keep servo track spacing constant across the medium. The methods and systems are disclosed in connection with a rotary actuator having spaced read and write heads. Similar methods are disclosed for writing trigger or timing bursts of the propagation pattern.