Optimal Feed Forward Profiles for Dynamic Flying Height Control in Hard Disk Drives
نویسندگان
چکیده
A dynamic model of the resistance heater in a thermal flying height control (TFC) slider of a hard disk drive is identified and used for dynamic flying height control. Experimental data obtained on a spin stand and the generalized realization algorithm are used for identification of a discrete-time dynamic model of the resistance heater (thermal actuator). The flying height change is measured using servo burst information written onto the disk surface. Based on the identified discrete-time model of the heater and convex optimization techniques, a computational scheme is proposed to obtain optimized feed forward input profiles to the heater element that minimize repeatable flying height variations and enable low flying heights.
منابع مشابه
Servo Signal Data Processing for Flying Height Control in Hard Disk Drives
In recent years, thermal actuated flying height control has been implemented in Hard Disk Drives (HDD) to reduce the effect of flying height variations due to manufacturing tolerances or write current introduced pole tip protrusion (Fig. 1). A stable low flying height is necessary to achieve low bit error rates (BER) [1]. Thermal flying height control is used in a “static manner” in current dis...
متن کاملReal-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 ...
متن کاملServo Signal Data Processing for Flying Height Control in Hard
Introduction In recent years, thermal actuated flying height control has been implemented in Hard Disk Drives (HDD) to reduce the effect of flying height variations due to manufacturing tolerances or write current introduced pole tip protrusion (Fig. 1). A stable low flying height is necessary to achieve low bit error rates (BER) [1]. Thermal flying height control is used in a “static manner” i...
متن کاملDesign and Dynamics of Flying Height Control Slider With Piezoelectric Nanoactuator in Hard Disk Drives
To achieve the areal density goal in hard disk drives of 1 Tbit/ in.2 the minimum physical spacing or flying height (FH) between the read/write element and disk must be reduced to 2 nm. A brief review of several FH adjustment schemes is first presented and discussed. Previous research showed that the actuation efficiency (defined as the ratio of the FH reduction to the stroke) was low due to th...
متن کاملAdaptive Regulation of the Flying Height Based on Hybrid Actuator in Near-field Optical Disk Drives
In the next generation near-field optical data storage systems, higher data transfer rate and higher data density require the optical pickup head to maintain a constant sub-micrometer flying height above the rotating disk surface without any collisions. However, suspension vibration and force disturbance, as well as disk vibration make it difficult to maintain the desired flying height during d...
متن کامل