Patents by Inventor Martin Aureliano Hassner
Martin Aureliano Hassner has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
-
Patent number: 10032476Abstract: In general, techniques are described for monitoring health of a head in a magnetic data storage drive. A health controller may be configured to receive multi-variate sensor signals indicative of a respective reference value at least one head parameter, wherein the respective reference value is based in part on at least one initial measurement of parameters of the head obtained at a first time, determine a respective predicted current value based at least in part on a respective fixed-drift model and the multi-variate sensor signals, determine a respective actual current value that is based at least in part on at least one current measurement of the head obtained at a second time later than the first time, determine a health status for the head, and store the health status in memory.Type: GrantFiled: November 9, 2016Date of Patent: July 24, 2018Assignee: Western Digital Technologies, Inc.Inventors: Sridhar Chatradhi, Saurabh Deoras, Martin Aureliano Hassner, Natasa Letourneaut, Satoshi Yamamoto
-
Publication number: 20180130494Abstract: In general, techniques are described for monitoring health of a head in a magnetic data storage drive. A health controller may be configured to receive multi-variate sensor signals indicative of a respective reference value at least one head parameter, wherein the respective reference value is based in part on at least one initial measurement of parameters of the head obtained at a first time, determine a respective predicted current value based at least in part on a respective fixed-drift model and the multi-variate sensor signals, determine a respective actual current value that is based at least in part on at least one current measurement of the head obtained at a second time later than the first time, determine a health status for the head, and store the health status in memory.Type: ApplicationFiled: November 9, 2016Publication date: May 10, 2018Inventors: Sridhar Chatradhi, Saurabh Deoras, Martin Aureliano Hassner, Natasa Letourneaut, Satoshi Yamamoto
-
Publication number: 20170344425Abstract: In one example, the disclosure is directed to error-correcting code techniques for managing data in a hard drive. In some examples, a controller of a hard disk drive may cause data including a data band and an associated parity sector to be retrieved from non-volatile memory. The data band may include a number of virtual data tracks, and each virtual data track may include a respective plurality of sectors. The controller may determine that at least one sector of the respective plurality of sectors includes an error that renders the data in the at least one sector unreadable by the controller. The controller may send the data including the data band and the associated parity sector to a host device.Type: ApplicationFiled: May 26, 2016Publication date: November 30, 2017Inventors: Kei Akiyama, Martin Aureliano Hassner, Kirk Hwang, Satoshi Yamamoto
-
Publication number: 20170345456Abstract: In one example, the disclosure is directed to error-correcting code techniques for managing data by a host device. In some examples, in writing the data, a host device receives parity data, data and one or more error pointers from a storage device. Each respective error pointer references a location of a respective data sector of the data that contains an error. The host device determines, based at least in part on the one or more error pointers, a first data sector of the data that contains an error. The host device recovers, based at least in part on the parity data, the data, and the one or more error pointers, the first data sector.Type: ApplicationFiled: May 26, 2016Publication date: November 30, 2017Inventors: Martin Aureliano Hassner, Kirk Hwang, Laurence Morris Morkre, Satoshi Yamamoto
-
Patent number: 9548070Abstract: A method, apparatus, and system for implementing head degradation detection and prediction for hard disk drives (HDDs) are provided. Statistical parameter stability tests are used that are calculated as Confidence Intervals (CIs) from HDD parameter measurements. HDD parameters include, for example, change or delta in fly height (dFH), magnetic resistor resistance (MRR) head values, servo variable gain amplifier (SVGA) readback amplitude values, that are used in conjunction with two or more confidence level indicators and an Auto-Regressive Integrated Moving-Average (ARIMA) (p, d, q) predictor for head degradation detection and field failure prediction.Type: GrantFiled: June 25, 2015Date of Patent: January 17, 2017Assignee: Western Digital Technologies, Inc.Inventors: Sridhar Chatradhi, Martin Aureliano Hassner, Natasa Letourneaut, Satoshi Yamamoto
-
Publication number: 20160379676Abstract: A method, apparatus, and system for implementing head degradation detection and prediction for hard disk drives (HDDs) are provided. Statistical parameter stability tests are used that are calculated as Confidence Intervals (CIs) from HDD parameter measurements. HDD parameters include, for example, change or delta in fly height (dFH), magnetic resistor resistance (MRR) head values, servo variable gain amplifier (SVGA) readback amplitude values, that are used in conjunction with two or more confidence level indicators and an Auto-Regressive Integrated Moving-Average (ARIMA) (p, d, q) predictor for head degradation detection and field failure prediction.Type: ApplicationFiled: June 25, 2015Publication date: December 29, 2016Inventors: Sridhar Chatradhi, Martin Aureliano Hassner, Natasa Letourneaut, Satoshi Yamamoto
-
Patent number: 9286159Abstract: Data storage devices using a two-level ECC scheme are described. Embodiments of the invention allow the recovery of sectors in a squeezed group of tracks in a that includes both a single track level ECC scheme and a track band ECC scheme that functions across the set of tracks in the band. The track band ECC scheme uses additional parity information calculated using input data from multiple tracks to allow correction across tracks.Type: GrantFiled: November 6, 2013Date of Patent: March 15, 2016Assignee: HGST Netherlands B.V.Inventors: Sridhar Chatradhi, Martin Aureliano Hassner, Kirk Hwang, Satoshi Yamamoto
-
Patent number: 9229813Abstract: Data storage devices are described with an ECC system that generate additional on-demand ECC information for a previously written track to provide for correction of data errors in the track and thereby avoid having to rewrite the track. Embodiments of the invention address the squeeze-error problem that arises when writing the next (second) track in a sequence causes errors to be introduced in the adjacent previously written (first) track. In alternative embodiments the existence of the data errors in the first track can be detected by reading the track or by estimating the number of likely errors using head position data measured while writing the first and second tracks. The additional on-demand ECC information can be written on any track that is available.Type: GrantFiled: March 6, 2014Date of Patent: January 5, 2016Assignee: HGST Netherlands B.V.Inventors: Sridhar Chatradhi, Martin Aureliano Hassner, Kirk Hwang, Satoshi Yamamoto
-
Publication number: 20150363263Abstract: ECC Encoders that process packets of p bits (with p>1) in a data block in parallel and generate a set of N parity/check bits that are stored along with the original data in the memory block. Encoders according to the invention can be used to create a nonvolatile NAND Flash memory write cache with BCH-ECC for use in a disk drive that can speed up the response time for some write operations. Encoder embodiments of the invention use Partial-Parity Feedback along with a XOR-Matrix Logic Module, which calculates N output bits from p input bits, and a Shift Register Module that accumulates N check bits. The XOR-Matrix Logic Module is designed using a precalculated Matrix of p×N bits, which is translated into VHDL design language to generate the hardware gates. High-Order p-bit Partial-Parity Feedback improves over LFSR designs and achieves Minimal Critical Path Length:=p.Type: ApplicationFiled: June 12, 2014Publication date: December 17, 2015Inventors: Martin Aureliano Hassner, Kirk Hwang
-
Publication number: 20150254135Abstract: Data storage devices are described with an ECC system that generate additional on-demand ECC information for a previously written track to provide for correction of data errors in the track and thereby avoid having to rewrite the track. Embodiments of the invention address the squeeze-error problem that arises when writing the next (second) track in a sequence causes errors to be introduced in the adjacent previously written (first) track. In alternative embodiments the existence of the data errors in the first track can be detected by reading the track or by estimating the number of likely errors using head position data measured while writing the first and second tracks. The additional on-demand ECC information can be written on any track that is available.Type: ApplicationFiled: March 6, 2014Publication date: September 10, 2015Applicant: HGST Netherlands B.V.Inventors: Sridhar Chatradhi, Martin Aureliano Hassner, Kirk Hwang, Satoshi Yamamoto
-
Publication number: 20150128008Abstract: Data storage devices using a two-level ECC scheme are described. Embodiments of the invention allow the recovery of sectors in a squeezed group of tracks in a that includes both a single track level ECC scheme and a track band ECC scheme that functions across the set of tracks in the band. The track band ECC scheme uses additional parity information calculated using input data from multiple tracks to allow correction across tracks.Type: ApplicationFiled: November 6, 2013Publication date: May 7, 2015Applicant: HGST Netherland B.V.Inventors: Sridhar Chatradhi, Martin Aureliano Hassner, Kirk Hwang, Satoshi Yamamoto
-
Patent number: 8856618Abstract: A technique for recovering of “squeezed” sectors in a set of sequential sectors such as are used in Shingled Magnetic Recording (SMR) is described. Embodiments of the invention use a programmable erased sector recovery scheme, which is a concatenation of a “Cauchy-type” track erasure correction code, together with a media-error correction code that generates N-weighted parity-sectors per track and is capable of replacing up to N-erased sectors per track in any possible combination.Type: GrantFiled: October 4, 2012Date of Patent: October 7, 2014Assignee: HGST Netherlands B.V.Inventors: Kei Akiyama, Sridhar Chatradhi, Jonathan Darrel Coker, Martin Aureliano Hassner, Kirk Hwang, Roger William Wood
-
Patent number: 8736997Abstract: A method, apparatus, and system are provided for implementing magnetic defect location detection on-the-fly for hard disk drives. A magnetic media readback signal of a hard disk drive is demodulated to generate phase modulation (PM) and amplitude modulation (AM) signals. A new coordinate plane defined by a combined phase modulation (PM) and amplitude modulation (AM) phasor-defect detector calculation function used to locate magnetic defects on-the-fly.Type: GrantFiled: June 13, 2012Date of Patent: May 27, 2014Assignee: HGST Netherlands B.V.Inventors: Richard Leo Galbraith, Weldon Mark Hanson, Martin Aureliano Hassner, Travis Roger Oenning, Satoshi Yamamoto
-
Publication number: 20140101515Abstract: A technique for recovering of “squeezed” sectors in a set of sequential sectors such as are used in Shingled Magnetic Recording (SMR) is described. Embodiments of the invention use a programmable erased sector recovery scheme, which is a concatenation of a “Cauchy-type” track erasure correction code, together with a media-error correction code that generates N-weighted parity-sectors per track and is capable of replacing up to N-erased sectors per track in any possible combination.Type: ApplicationFiled: October 4, 2012Publication date: April 10, 2014Applicant: HGST NETHERLANDS B.V.Inventors: Kei Akiyama, Sridhar Chatradhi, Jonathan Darrel Coker, Martin Aureliano Hassner, Kirk Hwang, Roger William Wood
-
Patent number: 8665545Abstract: A “write-squeeze-verify” method is used for verification of the data that has been written in the annular bands of a shingled magnetic recording disk drive. The writing of data along a track overwrites a portion of the previously written track and thus “squeezes” the data of the previously written track to thereby form a “shingled data track” (SDT). The data in each SDT is read back and verified by an error correction check using error correction bits associated with the data written in the SDT, or by comparing the readback data with the data stored in memory. If the data read back is not verified, a write error counter is incremented and a write error frequency is calculated. One or more attempts to write the data can be performed. If the data in the SDT cannot be verified after the attempted rewrite(s), then a “re-try fail” is reported.Type: GrantFiled: December 12, 2011Date of Patent: March 4, 2014Assignee: HGST Netherlands B.V.Inventors: Jonathan Darrel Coker, Martin Aureliano Hassner, Kirk Hwang, Bruce Alexander Wilson, Roger William Wood
-
Patent number: 8654464Abstract: A method, apparatus, and system are provided for implementing magnetic defect classification using phase modulation for hard disk drives. A magnetic media readback signal of a hard disk drive is processed to identify predefined phase modulation (PM) characteristics to implement magnetic defect classification of magnetic media bump and pit defects.Type: GrantFiled: October 19, 2011Date of Patent: February 18, 2014Assignee: HGST Netherlands B.V.Inventors: Richard Leo Galbraith, Weldon Mark Hanson, Martin Aureliano Hassner, Travis Roger Oenning, Satoshi Yamamoto
-
Publication number: 20130335841Abstract: A method, apparatus, and system are provided for implementing magnetic defect location detection on-the-fly for hard disk drives. A magnetic media readback signal of a hard disk drive is demodulated to generate phase modulation (PM) and amplitude modulation (AM) signals. A new coordinate plane defined by a combined phase modulation (PM) and amplitude modulation (AM) phasor-defect detector calculation function used to locate magnetic defects on-the-fly.Type: ApplicationFiled: June 13, 2012Publication date: December 19, 2013Applicant: HGST NETHERLANDS B.V.Inventors: Richard Leo Galbraith, Weldon Mark Hanson, Martin Aureliano Hassner, Travis Roger Oenning, Satoshi Yamamoto
-
Publication number: 20130148225Abstract: A “write-squeeze-verify” method is used for verification of the data that has been written in the annular bands of a shingled magnetic recording disk drive. The writing of data along a track overwrites a portion of the previously written track and thus “squeezes” the data of the previously written track to thereby form a “shingled data track” (SDT). The data in each SDT is read back and verified by performing an error correction check using error correction bits associated with the data written in the SDT, or by comparing the readback data with the data stored in memory. If the data read back is not verified, a write error counter is incremented and a write error frequency is calculated. One or more attempts to write the data can be performed. If the data in the SDT cannot be verified after the attempted rewrite(s), then a “re-try fail” is reported.Type: ApplicationFiled: December 12, 2011Publication date: June 13, 2013Inventors: Jonathan Darrel Coker, Martin Aureliano Hassner, Kirk Hwang, Bruce Alexander Wilson, Roger William Wood
-
Publication number: 20130100550Abstract: A method, apparatus, and system are provided for implementing magnetic defect classification using phase modulation for hard disk drives. A magnetic media readback signal of a hard disk drive is processed to identify predefined phase modulation (PM) characteristics to implement magnetic defect classification of magnetic media bump and pit defects.Type: ApplicationFiled: October 19, 2011Publication date: April 25, 2013Applicant: Hitachi Global Storage Technologies Netherlands B. V.Inventors: Richard Leo Galbraith, Weldon Mark Hanson, Martin Aureliano Hassner, Travis Roger Oenning, Satoshi Yamamoto
-
Patent number: 7272777Abstract: An efficient method for finding all the possible corrections of a bust of length b and e random errors consists of finding a polynomial whose roots are the candidate location for l—the location of the beginning of the burst—thus avoiding the search over all possible values of l (it is assumed that the burst is non-trivial, i.e., at least one of its errors has a non-zero value). In order to reduce the number of spurious solutions, it is assumed that the number of syndromes is t=2e+b+s, where s is at least 2. The larger the value of s the less likely it is that the algorithm will generate “spurious” solutions. Once the location of the burst is known, standard procedures are used to determine the magnitudes of the burst errors and the location and magnitude of the random errors.Type: GrantFiled: June 4, 2003Date of Patent: September 18, 2007Assignee: International Business Machines CorporationInventors: Martin Aureliano Hassner, Barry Marshall Trager, Shumel Winograd