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Effect of inspection performance in smart manufacturing system based on human quality control system

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Chang Wook Kang
Chang Wook Kang
Chang Wook Kang
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Muhammad Babar Ramzan at National Textile University
Muhammad Babar Ramzan
Biswajit Sarkar at Yonsei University
Biswajit Sarkar
Muhammad Imran at Institute of Business Administration Karachi
Muhammad Imran
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Abstract

Quality control at every stage of manufacturing is a key aspect of the quality management system of any organization. Inspection at different stages of manufacturing is essential to achieve required quality of the product. This knowledge area has been studied extensively in the past with respect to inspection strategies, inspection location, and inspection intervals to minimize inspection cost. However, there is a lack of literature that examines the relationship between inspection performance and factors related to human labor and inspection time of different products. Here, offline inspection is investigated to achieve the process target values by determining the optimal number of inspectors for different products. Three skill levels for inspectors are selected on the basis of their inspection errors, inspection quantities, and inspection cost. The purpose of this study is to achieve the optimum results of objective functions that consist of inspection cost, outgoing quality, and inspection quantity by determining the optimal value of decision variables, i.e., the number of inspectors with respect to their skill. A multi-objective optimization model is developed using a stochastic approach to determine the optimal results of the objective functions and decision variables. Firstly, goal programming is employed to verify the optimization model by using numerical examples. Secondly, sensitivity analysis is considered to illustrate the effect of incoming quantity on inspection performance and optimal combination of decision variables.
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ORIGINAL ARTICLE
Effect of inspection performance in smart manufacturing system
based on human quality control system
Chang Wook Kang
1
&Muhammad Babar Ramzan
2
&Biswajit Sarkar
1
&
Muhammad Imran
1
Received: 5 April 2017 /Accepted: 11 September 2017 /Published online: 3 October 2017
#Springer-Verlag London Ltd. 2017
Abstract Quality control at every stage of manufacturing is a
key aspect of the quality management system of any organi-
zation. Inspection at different stages of manufacturing is es-
sential to achieve required quality of the product. This knowl-
edge area has been studied extensively in the past with respect
to inspection strategies, inspection location, and inspection
intervals to minimize inspection cost. However, there is a lack
of literature that examines the relationship between inspection
performance and factors related tohuman labor and inspection
time of different products. Here, offline inspection is investi-
gated to achieve the process target values by determining the
optimal number of inspectors for different products. Three
skill levels for inspectors are selected on the basis of their
inspection errors, inspection quantities, and inspection cost.
The purpose of this study is to achieve the optimum results
of objective functions that consist of inspection cost, outgoing
quality, and inspection quantity by determining the optimal
value of decision variables, i.e., the number of inspectors with
respect to their skill. A multi-objective optimization model is
developed using a stochastic approach to determine the opti-
mal results of the objective functions and decision variables.
Firstly, goal programming is employed to verify the optimiza-
tion model by using numerical examples. Secondly, sensitivity
analysis is considered to illustrate the effect of incoming quan-
tity on inspection performance and optimal combination of
decision variables.
Keywords Quality control .Offline inspection .Inspection
performance .Inspection time .Goal programming
1 Introduction
The inspection process and skill of inspector are important for
any manufacturing system [1]. Even though, the recent ad-
vancements in manufacturing systems have been character-
ized by precision of work through automation [2]. However,
it is very difficult to automate any manufacturing system due
to budget constraints, space constrains, or lack of skilled labor.
Thus, the inspection process is controlled by human labor and
it is the necessity that the judgment of the human labor is
skilled, semi-skilled, or low-skilled inspectors. The job, in
the complex manufacturing sector, should be assigned accord-
ing to the skill of the inspector such that different skill levels
may have different inspection loads [3]. Due to the availability
of funds, the manufacturing system can be made automated in
several countries. However, for other countries, the labor cost
is much cheaper due to the availability of manpower. Thus, for
some countries, manufacturing industries prefer to use human
labor for inspection purposes with minimum cost rather than
the automated system. Therefore, the skills of those inspectors
should be judged properly before assigning any job. That ma-
jor research gap is solved by this research problem.
Two types of inspections are most commonly used during
the manufacturing process: online inspection and offline in-
spection [4]. Online inspection facilitates to monitor quality
level during the manufacturing process, while offline inspec-
tion inspects the finished products [5,6]. This study has in-
vestigated the offline inspection case, where human labor of
different skill levels performs the process of inspections.
Offline inspection has been extensively examined in past to
decrease inspection cost by considering inspection errors,
*Biswajit Sarkar
bsbiswajitsarkar@gmail.com
1
Department of Industrial and Management Engineering, Hanyang
University, Ansan, Gyeonggi-do 15588, Republic of Korea
2
Department of Garment Manufacturing, National Textile University,
Faisalabad, Pakistan
Int J Adv Manuf Technol (2018) 94:4351–4364
DOI 10.1007/s00170-017-1069-4
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
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