摘要:
A method according to one embodiment includes setting a default friction value to a predetermined value, determining whether a primary velocity is valid, determining a velocity error, determining whether the velocity error is in a predetermined range, accumulating the velocity error when the velocity error is determined to be in the predetermined range, repeating, until a time period has elapsed, each of: the determining the velocity error, the determining whether the velocity error is in the predetermined range, and the accumulating the velocity error when the velocity error is determined to be in the predetermined range, and calculating a new friction value based on the accumulated velocity error.
摘要:
A method according to one embodiment includes selecting an initial radius value (Rfull) for an outgoing reel, where Rfull is the initial radius of a tape on the outgoing reel; unwinding the tape from the outgoing reel; computing a radius value of the tape on the outgoing reel during the unwinding; adjusting the computed radius with an offset calculated from a direct measurement of velocity from the tape position; and outputting the adjusted computed radius. A method according to another embodiment includes selecting an initial radius value (R0) for an incoming reel, where R0 is the initial radius of the incoming reel; winding the tape onto the incoming reel; computing a radius value of the tape on the incoming reel during the winding; adjusting the computed radius with an offset calculated from a direct measurement of velocity from the tape position; and outputting the adjusted computed radius.
摘要:
A servo system according to one embodiment includes at least one servo sensor for sensing a lateral position of a magnetic head with respect to at least one defined servo track of a longitudinal tape; a fine actuator configured to translate the magnetic head laterally with respect to the longitudinal tape; a coarse actuator configured to translate the fine actuator laterally with respect to the longitudinal tape; and a servo control. The servo control is configured to perform various operations that may be used to estimate a midpoint of lateral tape excursion of a flangeless tape path for calibrating a tape drive. Additional systems are also presented.
摘要:
A method for accurately adjusting skew in the presence of tape motion includes performing a calibration run of magnetic tape in a tape drive. During the calibration run, the method records skew readings at selected intervals. The method then finds a range associated with the skew readings, such as by finding a high and low skew reading. The method then finds a center point of the range, and a difference between the center point and a desired center point. The method applies the difference to each recorded skew reading to generate a target skew reading for each recorded skew reading. The method generates a skew error signal that reflects the difference between each recorded skew reading and each corresponding target skew reading. The skew error signal will generally be consistent even as the tape moves, thereby allowing a technician to easily adjust and optimize the skew.
摘要:
A data storage system according to one embodiment includes a head; a drive mechanism for passing a medium over the head; and a controller electrically coupled to the head. The system calculates a kurtosis value, using the current position error signal sample or derivative thereof, and adjusts a threshold value using the kurtosis value. The standard deviation or variance is compared to the threshold value, and writing is enabled when the standard deviation or variance does not exceed the threshold value.
摘要:
A data storage system according to one embodiment includes a head; a drive mechanism for passing a medium over the head; and a controller electrically coupled to the head. The system calculates a kurtosis value, using the current position error signal sample or derivative thereof, and adjusts a threshold value using the kurtosis value. The standard deviation or variance is compared to the threshold value, and writing is enabled when the standard deviation or variance does not exceed the threshold value.
摘要:
According to one embodiment, a method includes sensing a first servo sensor while a longitudinal tape is moved in a first direction; determining position error between the magnetic head and a desired position related to the at least one defined servo track; providing signals to operate a fine actuator to translate the magnetic head laterally in a manner to reduce the determined position error; calculating a first average position of the magnetic head for at least one first run-out cycle while the longitudinal tape is moved in the first direction; calculating a first offset of the magnetic head while the longitudinal tape is moved in the first direction; operating a coarse actuator to position the coarse actuator substantially at a target position using the first offset and the first average position.
摘要:
A method according to one embodiment includes selecting an initial radius value (Rfull) for an outgoing reel, where Rfull is the initial radius of a tape on the outgoing reel; unwinding the tape from the outgoing reel; computing a radius value of the tape on the outgoing reel during the unwinding; adjusting the computed radius with an offset calculated from a direct measurement of velocity from the tape position; and outputting the adjusted computed radius. A method according to another embodiment includes selecting an initial radius value (R0) for an incoming reel, where R0 is the initial radius of the incoming reel; winding the tape onto the incoming reel; computing a radius value of the tape on the incoming reel during the winding; adjusting the computed radius with an offset calculated from a direct measurement of velocity from the tape position; and outputting the adjusted computed radius.
摘要:
A servo system according to one embodiment includes at least one servo sensor for sensing a lateral position of a magnetic head with respect to at least one defined servo track of a longitudinal tape; a fine actuator configured to translate the magnetic head laterally with respect to the longitudinal tape; a coarse actuator configured to translate the fine actuator laterally with respect to the longitudinal tape; and a servo control. The servo control is configured to perform various operations that may be used to estimate a midpoint of lateral tape excursion of a flangeless tape path for calibrating a tape drive. Additional systems are also presented.
摘要:
A method to monitor the relative position of a magnetic tape disposed in a tape drive, where that tape drive includes a first tape reel motor and a second tape reel motor. The method provides a magnetic tape disposed on a first tape reel, and releaseably attaches the first tape reel to the first tape reel motor. The method further provides a second tape reel attached to the second tape reel motor. The method operates the first tape reel motor and the second tape reel motor to transfer the tape from the first tape reel onto the second tape reel while maintaining a running second reel rotation count. The method sets a second reel rotation count limit, and determines if the running second reel rotation count exceeds that second reel rotation count limit. If the running second reel rotation count exceeds the second reel rotation count limit, then the method discontinues operation of the tape reel motors.