Multi-floor layout design of cellular manufacturing systems

Abstract

This paper presents a novel integer linear programming model for designing multi-floor layout of cellular manufacturing systems. Three major and interrelated decisions are involved in the design of a cellular manufacturing system (CMS); namely cell formation (CF), group layout (GL) and group scheduling (GS). A novel aspect of this model is concurrently making the CF and GL decisions to achieve an optimal design solution. The proposed model integrating the CF and GL decisions can be used by researchers and practitioners to design GL of a CMS in a multi-floor factory. Other compromising aspects are: considering multi-floor layout to form cells in the different floors, considering multi-rows layout of equal area facilities in each cell, configuring cells in flexible shapes, calculating material handling cost based on the distance between the locations assigned to machines. The proposed model incorporates several design features including alternative process routings, operation sequence, processing time, production volume of parts, duplicate machines, machine capacity, purchasing machine, lot splitting, material flow between machines, intra-cell layout, inter-cell layout, multi-floor layout and flexible configuration. The objective is to minimize the total costs of intra-cell, inter-cell and inter-floor material handling, purchasing new machines and machine processing. The main constraints are demand satisfaction, cell size, machine time-capacity, material flow conservation and machine location. Two numerical examples are solved by the Lingo software to verify the performance of the proposed model and illustrate the model features.