Integration of Six Sigma methodology of DMADV steps with QFD, DFMEA and TRIZ applications for image-based automated inspection system development: a case study

Abstract

Purpose This paper aims to present the development of an automated inspection system (AIS) using an image-based analysis mechanism, called i-AIS. The development process of i-AIS used the Design Six Sigma (DSS) methodology. The steps of define, measure, analyze, design and verify (DMADV) are applied and integrated with specific analyses techniques of the quality function deployment (QFD), design failure mode effect analysis (DFMEA) and theory of inventive problem solving (TRIZ). The production process of adhesive tape is the focused case study in this research project, motivated by the high product defect rate complained by customers. Design/methodology/approach The development process of i-AIS was divided into five standard steps based on the DSS methodologies of DMADV. One of the key processes in this development was to systematically identify the right and intended features of i-AIS. This was carried out based on the application of the QFD technique. Another important process was to further investigate the possible causes of i-AIS failure, to function as intended. This investigative process was carried out based on the DFMEA technique, while the solution to minimize the risk of the identified failures was obtained from the TRIZ method. The final prototype of i-AIS was then presented in the design step. Findings Verification of the i-AIS prototype revealed its operation at an optimally intended mode that fulfilled the requirements of internal customers. Verification results also revealed that the sigma level has improved from 3.87 to 4.33. Meanwhile, the defect reduction rate is improved to 74.4% and downtime rate also recorded a significant improvement at 80.7% of reduction. Research limitations/implications The presented research work is carried out based on a customized case study. Although the proposed methodology can be applied to others cases towards design-based solution, some modifications maybe required based on to the unique features of the case study under consideration. Practical implications The presented research project indicated that the proposed methodology was successful to facilitate a structured and systematic process towards defect identification, classification, evaluation and generation of a solution. Originality/value The paper presents the development process of an AIS by considering comprehensive managerial aspects that are currently absent in the literature. An integrated DSS structure is proposed to systematically guide the development of i-AIS. The related managerial aspects such as identification of critical defects problem, customer requirement mapping, prototype design analysis and comparison measurements before and after i-AIS installation are considered in this research project.