Use of low-cost MEMS accelerometers for vibration compensation in hard disk drives

High track density in modern hard disk drives (HDD) can be achieved with fine servo-positioning of the heads, against all the disturbances acting on the system. Part of them are due to self-generated and external vibrations, which contribute to the off-track motion of the heads. Several authors have proposed the use of accelerometers and feedforward compensation in order to compensate for the vibration effects, but the cost of the accelerometer often surpassed the cost of the HDD itself In this paper, we report the use of a low-cost, MEMS based commercial accelerometer, in conjunction with a simple feedforward compensation scheme. As a result, a 20 dB reduction of PES with a 1 g, 18 Hz vibration is obtained. Also, a reduction of the effects of the self-generated vibration is obtained.