Experimental study of disk vibration reduction via stacked disks

In order to improve the position accuracy of testing and manufacturing equipments such as spin stand and servo track writer with minimal mechanical alternation, a stacked-disk approach whereby more than one normal recording media are stacked together for reading and writing on the disk surfaces is studied. Two 3.5-inch recording media are stacked together to test the effectiveness of reducing the vibrations and improving the position accuracy. The position error signals (PES) are measured and analyzed at different rotational speeds of 7200, 8400 and 10,200 rev/min. The results show that the dual-disk stack can reduce the amplitude of the PES by over 30% when the rotating speed is above 8400 rev/min.