International Research Journal of Advanced Engineering and Science ISSN (Online): 2455-9024 216 Ezeobi Stanislaus O., Nkanyi Nwadiogo Ginika, Mmaduekwe Blessing Chinwendu, and Akobundu Chinyere Ihuoma, “Positioning improvement for high speed performance of a hard disk drive of computer system,” International Research Journal of Advanced Engineering and Science, Volume 3, Issue 1, pp. 216-219, 2018. Positioning Improvement for High Speed Performance of a Hard Disk Drive of Computer System Ezeobi Stanislaus O. 1 , Nkanyi Nwadiogo Ginika 2 , Mmaduekwe Blessing Chinwendu 2 , Akobundu Chinyere Ihuoma 3 1 Department of Computer Engineering Technology, Anambra State Polytechnic, Mgbakwu, Anambra, Nigeria 2 Department of Computer Science, Anambra state Polytechnic, Mgbakwu, Anambra, Nigeria 3 Department of Computer Science, Evangel University, Akaeze, Ebonyi Nigeria Abstract— In order to have high speed data processing, storage and retrieval by the central processing unit (CPU) of a computer, it is expected of a hard disk drive (HDD) to operate at a high speed performance and efficient. This has presented positioning improvement for high speed performance of a hard disk drive of a computer system. A dynamic model of read/write (R/W) servo positioning system of an HDD was obtained. A digital compensator was designed using Matlab software. The designed compensator was integrated with servo positioning system. Simulation was performed in Matlab environment. The result obtained showed that the response performance of the compensated system to a unit step input improved significantly. This shows that the digital compensator greatly improved the positioning of the R/W, which invariably reflects the fact that high speed performance has been achieved. Keywords— CPU, Digital Compensator, HDD, Positioning system, Read/write. I. INTRODUCTION Computers are known to have hard disk drive (HDD) inside them. A hard disk drive is just an integral part of the computer system which is used as a long term storage space for data [1]. It functions to keep data safe regardless of the state of the computer system –whether it is ON or OFF. A typical hard disk drive has the following components parts: platters, the spindle, the read/write (R/W) heads, and actuator. Platters are circular discs found inside an HDD. The ones (1s) and zeros (0s) that make up the data are stored in the platters. The storage capacity of a hard drive can be increased by using several platters. In order to keep data stored on the platters organized and easier to find, they stored in tracks, sectors and clusters. Each platter is divided into concentric circles known as tracks. Each track is further divided into smaller units called sectors. The R/W heads interface between the magnetic media where the data is stored and electronic components in the HDD. The movement of the R/W heads is actually controlled by the R/W arm. The arm ensures that the heads are well position based on the data that needs to be read or written [2]. Information which are in form of bits are converted to magnetic pulses by the R/W head when it is to be stored on the platter (writing process) and then reverse the process while reading. The platters are kept in position and rotated by the spindle. The head actuator is a small motor which is instructed by the drive’s circuit board to control the R/W arm movement. It operates to ensure that the R/W heads are in exact and right position at all times. There are basically two main functions carried out by R/W head positioning servo mechanism in HDD. These are: track seeking and track following. Track seeking moves the read/write head from the present track to a specified destination track in minimum time using a bounded control effort. Track following maintains the head as close as possible to the destination track centre while information is being read from or written to the disk [12], [9]. Previous works in literature have been presented on improving the operation of an HDD. The study in [3] presented a servo position control in hard disk drive of a computer using model reference adaptive control integrating proportional integral and derivative (PID) algorithm. Robust track-following controller design in hard disk drives based on parameter dependent Lyapunov functions is presented in [4]. Boettcher et al [5] studied the modelling and control of a dual stage actuator hard disk drive. A hard disk drive mechanism vibration damping using disturbance observer is established in [6]. Design and control of a dual-stage drive servo system with a high-aspect ratio electrostatic microactuator is presented in [7]. Goh et al. [8] presented design and implementation of a hard disk drive servo system using robust and perfect tracking approach. Mbaocha et al. [9] presented compensator for optimum hard disk drive read/write head positioning and control. The research carried out in [10] presented discrete proportional integral and derivative (PID) control scheme for a hard disk drive servomechanism. Design and implementation of a high performance hard disk drive servo controller using genetic algorithm (GA) based two degree of freedom (2DOF) robust controller is presented in [11]. The objective of this paper is to design a digital compensator that will improve the positioning system of the read/write (R/W) head of a hard disk drive (HDD) for high speed performance. In order to have high speed data processing, storage and retrieval by the central processing unit (CPU) of a computer, it is expected of the HDD to be fast (high speed performance) and efficient. To achieve this, the positioning system of an HDD requires a compensator that will enable it operate optimally so as to preserve the integrity of the data/information stored in an HDD.