# US 10,504,545 B1 · Method and apparatus that modifies seek parameter to remediate cross-actuator interference > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,504,545 B1 - Document ID: US10504545B1 - Status: Granted - Kind: B1 - Application number: 16/259,108 - Filed: 2019-01-28 - Granted: 2019-12-10 - Earliest claimed: 2017-12-05 - Assignees: Seagate Technology LLC - Applicants: Seagate Technology LLC - Inventors: Mark Allen Gaertner; Evgeny Kharisov; Josiah Natan Wernow - Web page: https://patentgrep.com/patent/US10504545B1 ## CPC - G11B 5/5547: {"Seek" control and circuits therefor (G11B5/5556 takes precedence)} - G06F 3/0676: {Magnetic disk device} - G11B 5/4813: {Mounting or aligning of arm assemblies, e.g. actuator arm supported by bearings, multiple arm assemblies, arm stacks or multiple heads on single arm (G11B5/484 takes precedence)} - G11B 5/5578: {Multiple actuators addressing the same disk, e.g. to improve data rate or access rate} - G11B 27/36: Monitoring, i.e. supervising the progress of recording or reproducing {(for digital recording G11B20/00 and s.gr.; for monitoring, testing or measuring of TV recorders of the type covered by H04N5/76 and subgroups, see H04N17/06)} - G06F 3/0614: {Improving the reliability of storage systems} - G06F 3/0659: {Command handling arrangements, e.g. command buffers, queues, command scheduling} - G11B 5/54: with provision for moving the head into or out of its operative position or across tracks - G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R) - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) ## Abstract A faulty tracking condition affecting a first head driven by a first actuator of a hard disk drive is determined. The faulty tracking condition is caused by a second actuator of the hard disk drive that is moving while the first actuator is performing a tracking operation. Responsive to the determination of the faulty tracking condition, seek forces of the second actuator that cause the faulty tracking condition affecting the first head are reduced. A controller verifies that similar faulty tracking conditions are reduced with the first head in response to the reduction in seek forces. ## Claims ### Claim 1 A method comprising: setting at least one criterion that indicates a likelihood of cross-actuator interference from a second actuator that impacts a first head driven by a first actuator separate from the second actuator; modifying a seek parameter of the second actuator responsive to detecting the at least one criterion affecting the first head; and verifying that the modification of the seek parameter improves performance of the first head according to the at least one criterion. ### Claim 2 (depends on 1) The method of claim 1, wherein the at least one criterion comprises a number of off-track write faults of the first head. ### Claim 3 (depends on 1) The method of claim 1, wherein the at least one criterion comprises a number of seeks of the first actuator past an expected position. ### Claim 4 (depends on 1) The method of claim 1, wherein the at least one criterion comprises a time spent in susceptible mode by the first head. ### Claim 5 (depends on 1) The method of claim 1, wherein the modification to the seek parameter comprises rescheduling operations of the second actuator to reduce long seeks. ### Claim 6 (depends on 1) The method of claim 1, wherein the modification to the seek parameter comprises reducing an acceleration of the second actuator during seeks. ### Claim 7 (depends on 1) The method of claim 1, wherein the modification to the seek parameter comprises reducing a deceleration of the second actuator during the seeks. ### Claim 8 (depends on 1) The method of claim 1, wherein the modification of the seek parameter is scaled based on at least one of a magnitude and a type of the at least one criterion. ### Claim 9 A system comprising: a first actuator that drives a first head; a second actuator different from the first actuator that drives a second head different from the first head; and a controller coupled to the first and second actuators and configured to: set at least one criterion that indicates a likelihood of cross-actuator interference from the second actuator that impacts the first; modify a seek parameter of the second actuator responsive to detecting the at least one criterion affecting the first head; and verify that the modification of the seek parameter improves performance of the first head according to the at least one criterion. ### Claim 10 (depends on 9) The system of claim 9, wherein the at least one criterion comprises a number of off-track write faults of the first head. ### Claim 11 (depends on 9) The system of claim 9, wherein the at least one criterion comprises a number of seeks of the first actuator past an expected position. ### Claim 12 (depends on 9) The system of claim 9, wherein the at least one criterion comprises a time spent in susceptible mode by the first head. ### Claim 13 (depends on 9) The system of claim 9, wherein the modification to the seek parameter comprises rescheduling operations of the second actuator to reduce long seeks. ### Claim 14 (depends on 9) The system of claim 9, wherein the modification to the seek parameter comprises reducing an acceleration of the second actuator during seeks. ### Claim 15 (depends on 9) The system of claim 9, wherein the modification to the seek parameter comprises reducing a deceleration of the second actuator during the seeks. ### Claim 16 (depends on 9) The system of claim 9, wherein the modification of the seek parameter is scaled based on at least one of a magnitude and a type of the at least one criterion. ### Claim 17 An apparatus comprising: interface circuitry coupled to first and second actuators that drive respective first and second heads that read one or more disks; and a controller coupled to the interface circuitry and operable to: set at least one criterion that indicates a likelihood of cross-actuator interference from the second actuator that impacts the first; modify a seek parameter of the second actuator responsive to detecting the at least one criterion affecting the first head; and verify that the modification of the seek parameter improves performance of the first head according to the at least one criterion. ### Claim 18 (depends on 17) The apparatus of claim 17, wherein the at least one criterion comprises any combination of a number of off-track write faults of the first head, a number of seeks of the first actuator past an expected position, and a time spent in susceptible mode by the first head. ### Claim 19 (depends on 17) The apparatus of claim 17, wherein the modification to the seek parameter comprises at least one of rescheduling operations of the second actuator to reduce long seeks, reducing an acceleration of the second actuator during seeks, and reducing a deceleration of the second actuator during the seeks. ### Claim 20 (depends on 17) The apparatus of claim 17, wherein the modification of the seek parameter is scaled based on at least one of a magnitude and a type of the at least one criterion.