Artificial Intelligence Mechanisms on Interactive Modified Simplex Method with Desirability Function for Optimising Surface Lapping Process

Pongchanun Luangpaiboon,Sitthikorn Duangkaew

doi:10.1155/2014/864586

Abstract

A study has been made to optimise the influential parameters of surface lapping process. Lapping time, lapping speed, downward pressure, and charging pressure were chosen from the preliminary studies as parameters to determine process performances in terms of material removal, lap width, and clamp force. The desirability functions of the-nominal-the-best were used to compromise multiple responses into the overall desirability function level orDresponse. The conventional modified simplex or Nelder-Mead simplex method and the interactive desirability function are performed to optimise online the parameter levels in order to maximise theDresponse. In order to determine the lapping process parameters effectively, this research then applies two powerful artificial intelligence optimisation mechanisms from harmony search and firefly algorithms. The recommended condition of (lapping time, lapping speed, downward pressure, and charging pressure) at (33, 35, 6.0, and 5.0) has been verified by performing confirmation experiments. It showed that theDresponse level increased to 0.96. When compared with the current operating condition, there is a decrease of the material removal and lap width with the improved process performance indices of 2.01 and 1.14, respectively. Similarly, there is an increase of the clamp force with the improved process performance index of 1.58.

Highlights

The hard disk drive (HDD) precision components mainly consist of magnetic, mechanical, electromechanical, and electronic components
In the literature for the Harmony Search Algorithm (HSA) parameter levels, the BWMax, BWMin, harmony memory size (HMS), PHMCR and PPAR are recommended to be within the range of 1, [0.001, 0.1], [20, 50], [0.7, 0.95] and [0.3, 0.7], respectively
Various parameters from the Surface Lapping Process (SLP) can vary from application such as a lapping machine with different levels of speed and lapping plates, workstations for controlling lapping fixtures and the equipment to control the plate flatness

Summary

Introduction

The hard disk drive (HDD) precision components mainly consist of magnetic, mechanical, electromechanical, and electronic components. Under the current operating condition, the mean, standard deviation and an overall process performance index (Ppk) of all responses of material removal, surface lap width, and clamp force have unsatisfactory levels when compared to the target (Table 1).

Results

Conclusion