Servo signal processing for flying height control in hard disk drives
نویسندگان
چکیده
A novel method of measuring the relative headmedium spacing based on a measurement in the servo sectors is developed and simulated using a read back signal model. The spacing measurement is tested experimentally on a spin stand where the flying height is varied using the resistance heater element in a thermal flying height control slider. In addition, voltage step response measurements were obtained. The data were used to perform system identification and estimate the dynamics of the thermal actuator. The model can potentially be used for thermal flying height control.
منابع مشابه
Real-time signal processing for flying height measurement and control in hard drives subject to shock and vibration
Three readback signal detection methods are inyestgated for real-time flying height or head disk spacing variation measurement under vibration conditions. This is carried out by theoretical analysis, numerical simulation, and experimental study. The first method (amplitude detection) provides a simple way to study the head disk spacing change. The second method ( PW50 parameter estimation) can ...
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