Abstract: Techniques for detection of impending data errors in a mass storage system, such as a track squeeze problem in an electromagnetic disk drive, and then repairing the impending problem, such as by rewriting the affected tracks. In many cases the problem is detected and repair is effected when the original data can still be read. In other cases, when the data is no longer readable on the disk in question, but when the disk is part of a Redundant Array of Independent Disks (RAID) system, or other system in which higher layer fault tolerance mechanisms are implemented, the missing data can be recovered via these mechanisms. The recovered data is then used to repair the track squeeze problem. The invention can be implemented as firmware in a storage system, as a component of a general purpose operating system, or inside individual disk drives, or it can use a combination of these implementations.

Abstract: An energy absorbing retractor having a frame, locking mechanisms to initially stop a spool from rotating in a belt protraction direction, the spool rotationally supported relative to the frame, a seat belt wound about the spool, and biasing device to retract the seat belt, a two-sided torsion bar for generating at least a first level of reaction torque on the spool permitting the spool to rotate in a controlled manner in a belt protracting direction including a torsion bar having a middle portion fixedly coupled to the spool to prevent relative rotation therebetween, a first torsion rod extending therefrom, the first torsion rod including a first end coupled to a first locking mechanism to prevent the first end from rotating upon such coupling, whereby upon locking of the first end, and the loading of the spool, the first torsion rod is twisted to generate a first level of control force.