The first PC HDDs used stepper motors and absolute positioning with cylinder geometry, just like floppy drives. Then they moved to voice coils and remote encode

The first PC HDDs used stepper motors and absolute positioning with cylinder geometry, just like floppy drives. Then they moved to voice coils and remote encoders (e.g. early Quantum drives), dedicated servo surface (drives with this report an odd number of heads), and finally embedded servo with non-cylinder-based layouts where each surface can have different track pitches and sectors per track. I wouldn't call that "the same basic mechanism" as there have been lots of refinement over the years, but it turns out that having the heads themselves find what they need to read was the best solution.