• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.14 no.12
• /
• pp.1347-1353
• /
• 2004

With respect to the researches of the optical flying head(OFH) , the head-gimbal assembly should be analyzed to guarantee the stable fabrication and the characteristics of shock resistance. The suitable design is proved through the Probabilistic analysis of the design parameters and material properties of the model. Probabilistic analysis is a technique that be used to assess the effect of uncertain input parameters and assumptions on your analysis model. Using a probabilistic analysis you can find out how much the results of a finite elements analysis are affected by uncertainties in the model. Another factor is analysis of the dynamic shock analysis. For the mobile application, one of the important requirements is durability under severe environmental condition, especially, resistance to mechanical shock. An important challenge in the disk recording is to improve disk drive robustness in shock environments. If the system comes in contact with outer shock disturbance. the system gets critical damage in head-gimbal assembly or disk. This paper describes probabilistic and dynamic shock analysis of head-gimbal assembly in micro MO drives using OFH slider.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2004.05a
• /
• pp.189-194
• /
• 2004

As a disk drive becomes widely used in portable environments, one of the important requirements is durability under severe environmental condition, especially, resistance to mechanical shock. An important challenge in the disk recording is to improve disk drive robustness in shock environments. If the system comes In contact with outer shock disturbance, the system gets critical damage in head-gimbal assembly or disk. This paper describes analysis of a HGA(head-gimbal assembly) in micro MO drives to shock loading during both non-operating state and operating state. A finite element model which consists of the disk, suspension, slider and air bearing was used to find structural response of micro MO drives. In the operational case. the air bearing is approximated with four linear elastic springs. The commercially available finite element solver, ANSYS/LS-DYNA, is used to simulate the shock response of the HGA in micro MO drives. In this paper, the mechanical robustness of the suspension is simuiated considering the shock responses of the HGA.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2002.11b
• /
• pp.140-145
• /
• 2002

In high-capacity disk drives with ever-growing track density, the allowable level of position error signal (PES) is becoming smaller and smaller. A substantial portion of the PES is caused by disk vibration. This can be reduced by using a head gimbal assemblies (HGAs) that do not confine the slider movement to the vertical direction to disks, but allow movement to the radial direction of disks with respect to disk vibration. Several types of HGAs are proposed for such radial motion of the slider. Experimental results show that the PES levels are reduced by the proposed HGA-design concepts.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2002.11a
• /
• pp.320.2-320
• /
• 2002

In high-capacity disk drives with ever-growing track density, the allowable level of position error signal (PES) is becoming smaller and smaller. A substantial portion of the PES is caused by disk vibration. This can be reduced by using a head gimbal assemblies (HGAs) that do not confine the slider movement to the vertical direction to disks, but allow movement to the radial direction of disks with respect to disk vibration. Several types of HGAs are proposed for such radial motion of the slider. (omitted)

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2002.11b
• /
• pp.570-575
• /
• 2002

Servo performance of a disk drive is greatly affected by the mechanical resonance frequencies of the head gimbal assembly (HSA). It is important factor to allow broader bandwidths for servo system in improving overall drive performance. In this paper, an optimal design for ODD suspension is attempted to increase resonance frequencies in tracking direction. Initial model was designed and the design parameter was defined to the model. The mode frequency variation for the change of design parameter was observed by modal analysis using the finite element method(FEM). The sensitivity matrix was calculated from the observed data and so through sensitivity analysis, an optimized ODD suspension was designed to have the higher resonant frequency than the initial model.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2002.11a
• /
• pp.359.1-359
• /
• 2002

Servo performance of a disk drive is greatly affected by the mechanical resonance frequencies of the head gimbal assembly(HGA). It is important (actor to allow broader bandwidth for servo system in improving overall drive performance. In this paper, an optimal design for ODD suspension is attempted to increase resonance frequencies. It was decided that the first resonant frequency in tracking direction was higher than 5㎑. (omitted)

• Journal of the Korean Society for Precision Engineering
• /
• v.18 no.4
• /
• pp.9-18
• /
• 2001

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.33 no.8
• /
• pp.760-766
• /
• 2009

In the manufacturing process of HDD, ball swaging method is commonly used to joint the Head Gimbal Assembly(HGA) with the arm of the actuator. The hub on the HGA is placed into the hole of the actuator arm, and the hub and arm is bonded by the pressure of steel ball. The pressure for plastic deformation on the baseplate causes the undesirable deformation on HGA, such as tilting, flying height change of head. After obtaining the key parameters that have large sensitivity on the swaging process, the optimal shape of baseplate is proposed to increase the static performance during swaging process. Contribution of the proposed design for the swaging performance is verified by contact simulation with elasto-plastic deformation.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2001.05a
• /
• pp.917-923
• /
• 2001

This paper presents the fabrication and testing results of a dual stage microactuator system for fine positioning of magnetic heads in hard disk drives. An electrostatic rotary microactuator was newly designed and fabricated. The microactuator was integrated into the head gimbal assembly of a disk drive system and its dynamic characteristics were investigated. Experimental results show that natural frequency and voltage gain of the microactuator are 4.3 KHz and 25 nm/V and the dual stage microactuator system achieves the tracking accuracy of 30 nm.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.21 no.11
• /
• pp.1885-1895
• /
• 1997

As track density needs to increase to the order of 10, 000 tpi, the suspension has become a critical component in hard disk drives. One of the main obstacles to attain high track density is the structural resonances of the suspension in lateral direction. We investigate the suspension dynamics through the experimental modal analysis and the finite element method. An LDV (Laser Doppler Vibrometer) is employed to measure the response of the suspension which is excited by a shaker and an inpulse hammer for the free condition and the loaded condition, respectively. After comparing the experimental and numerical results, we study how the initial geometry of the bend region affects the suspension dynamics. It is found that the natural frequency of the sway mode decreases as the bend ratio and the bend angle increase. The shape of torsional mode changes as the mass of a slider increases, resulting in a local decrease in the natural frequency.