Active Vibration Control Research Of The Hard Disk Driver Suspension

With the hard disk capacity and rotation speed continually increasing, the precision of the I/O head positioning control has become more and more high. The traditional method was passive control to optimize the structure of HDD (Hard Disk Driver), this paper presented to make use of the active control principle to restrain the vibration of HDD. By utilizing the piezoelectric material (PZT) as the sensor and actuator, a vibration damping controller had been designed and tested based on the xPC Target system. The main contents of this paper are as following: 1,The suspension of HDD integrated with the PZT actuator was simulated by finite element software ANSYS. An optimized structure with PZT actuated was obtained by analyzing the driving capacity in different states. 2,The model was identified by least-squares method based on xPC Target software. 3,The theory of H_∞ robust control was briefly introduced and some problems about the H_∞ standard control, the robust stability and the mixed sensitivity were presented . In this paper, the common process to solve the controller was also presented. 4,According to the model identified by the least-squares method, the robust weighting function and performance weighting function were designed. Then the H∞ controller was obtained, the simulation results showed that the H∞ control principle was effective to restrain the vibration of the suspension. 5,Based on xPC Target some experiments have been done, the experimental results show the effectiveness of theoretical analysis. Further research direction was also put forward.