Just as in the freestyle, headpositioning plays an important roll in the backstroke.
和自由泳一样，头部的位置对于仰泳来说也是至关重要的。
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The split morph can be used as precision positioner, especially as the secondary actuator in dual stage headpositioning servo system of high density hard disk drives.
The main circuits of a magnetic headpositioning system with a density of 8 tracks per millimeter (TPM) based on a 4 TPM system are described with the performance of the system analysed and discussed.