Method for analyzing magnetic media surface in a disk drive for indications of head impact

In a disk drive having a plurality of magnetic media surfaces on rotating disks, and having read/write heads that each are associated with a respective media surface, a method for analyzing the plurality of media surfaces for indications of head impacts, comprising the steps of:

• scanning the plurality of media surfaces to detect errors indicative of media defects;
• recording location information for each detected error;
• identifying defect clusters based on the location information;
• generating a confidence factor for each defect cluster based on a comparison between the defect cluster and a representation of the physical dimensions of the heads;
• combining the confidence factors of defect clusters at corresponding locations on the plurality of media surfaces to generate a combined confidence factor that indicates impacts between the heads and the respective media surfaces;
• and
• determining whether the combined confidence factor indicates impacts between the plurality of heads and the respective media surfaces.

A disk drive having a rotating disk with a magnetic media surface and having a read/write head, comprising:

• means for scanning a media surface to detect errors indicative of media defects;
• means for recording location information for each detected error;
• means for identifying defect clusters based on the location information;
• means for generating at least one confidence factor based on a comparison between the defect clusters and a representation of the physical dimensions of the head;
• and
• means for determining whether the at least one confidence factor indicates an impact between the head and the media surface.

A disk drive having a plurality of magnetic media surfaces on rotating disks, and having read/write heads that each are associated with a respective media surface, comprising:

• means for scanning the plurality of media surfaces to detect errors indicative of media defects;
• means for recording location information for each detected error;
• means for identifying defect clusters based on the location information;
• means for generating a confidence factor for each defect cluster based on a comparison between the defect cluster and a representation of the physical dimensions of the heads;
• means for combining the confidence factors of defect clusters at corresponding locations on the plurality of media surfaces to generate a combined confidence factor that indicates impacts between the heads and the respective media surfaces;
• and
• means for determining whether the combined confidence factor indicates impacts between the plurality of heads and the respective media surfaces.