Determining lateral error offsets to adjust a lateral position at which to move a tape head with respect to a tape medium

Abstract

Provided are a controller, tape drive, and method for determining a lateral position at which to move a tape head. The tape head, comprising a first module having a first servo reader and a second module having a second servo reader, is rotated to rotate the second servo reader at skew angles with respect to the first servo reader. A determination is made of estimated lateral positions of the second reader at the skew angles. Expected lateral positions of the second servo reader at the skew angles are calculated from a calculated distance between the first and the second servo readers and the skew angles. Lateral error offsets, comprising differences of estimated lateral positions and expected lateral positions at the skew angles, are added to an error offset data structure used to adjust a target lateral position at which to position the tape head.