Balancing of parallel assembly lines with mixed-model product N Ismail Department of Mechanical and Manufacturing Faculty of Engineering, University Putra Malaysia, 43400, Selangor D.E., Malaysia napsiah@eng.upm.edu.my G. R. Esmaeilian Department of Mechanical and Manufacturing Faculty of Engineering, University Putra Malaysia, 43400, Selangor D.E., Malaysia gre@eng.upm.edu.my M. Hamedi Department of Mechanical and Manufacturing Faculty of Engineering, University Putra Malaysia, 43400, Selangor D.E., Malaysia Maryam.hamedi@gmail.com S. Sulaiman Department of Mechanical and Manufacturing Faculty of Engineering, University Putra Malaysia, 43400, Selangor D.E., Malaysia suddin@eng.upm.edu.my Abstract— The single-model assembly line is not efficient for today’s competitive industry because to respond the customer’s expectation, companies need to produce mixed- model products. This research takes advantages of the parallel assembly lines to balance mixed-model in parallel assembly line and allocating tasks of models to workstations to reduce the cycle times. To solve the problem, the meta-heuristic algorithms was developed and coded in MATLAB®. This research shows the modification of the mixed-model production into parallel assembly line and an algorithm can be used for more than two products together with different cycle times. In addition, now the modification allows Mixed-Model Parallel Assembly Line Balancing (MMPALB) becomes a useful tool to allocate all tasks of the mixed-model in the parallel lines, and balances with the minimum cycle time for each model. Keywords-component; mixd-model product, parallel assembly lines, artifitial intelegent, tabu search I. INTRODUCTION An assembly line consists of workstations that produce a product as it moves successively from one workstation to the next along the line, which this line could be straight, u-line or parallel until completed. To balance an assembly line, some methods have been originally introduced to increase productivity and efficiency. These objectives are achieved by reducing the amount of required manufacturing time to produce a finished product, by reduction in number of workstations or both of them. The Assembly Line Balancing Problem (ALBP) has been extensively studied [1], but it is still an important problem which many researchers try to create new design and balance for the ALBP to achieve more efficiency especially in new assembly line design like parallel assembly lines. The arrangement of tasks in workstation of an assembly line are followed by two main objectives [2-3]. The first one is type I problem that is related to determine the minimum number of required workstations to achieve the specified cycle time and the second one is type II for allocating the tasks to the workstations in such a way the maximum required time for the assembly at any given workstation be minimum in the all-available workstations. Comprehensive surveys of related researches have been appeared in [4-7] Many publications are available concerning the design, balancing and scheduling for Single, Multi and Mixed-Product lines. The mixed-model production defined as the products, which differ from each other with respect to size, color, material, or equipment, are manufactured on the same line [8]. This situation presents further challenges since tasks, processing times and precedence constraints vary from model to model. The Mixed-Model Assembly Line (MMAL) is a more complex to balance in which several types of the products are assembled simultaneously on the line which considering to the shape of line which in single line all tasks allocate in one and in parallel assembly line in more than one line. In addition, it entails the additional considerations of the interactions between the assembled models [9]. The importance of the MMAL Balancing Problem (MMALBP) in the modern industry encouraged several researches in the last few years. (e.g. Erel and Gökçen [10], Esmaeilian et al. [11-13], Gökçen and Erel [14], Jin and Wu [15], Kurashige et al. [16], Matanachai and Yano [17], Merengo et al. [18], Özcan and Toklu [19], Song et al. [20], and Vilarinho and Simaria [21]). In the other hand, Parallel Assembly Lines (PALs) are considered as production system, which consists of a number of assembly lines in parallel status. On the each line, a certain number of product(s) considering to type of product(s) manufactured observing a cycle time. By arranging the lines in a favorable style, it is possible to increase efficiency of the production system by combining workstations of neighbor lines during balancing the lines [12-13, 22-23]. Studies on the parallel lines are quite few [23]. In designing the PAL, Süer and Dagli [24] suggested heuristic procedures and algorithms to determine the number of lines and the line configuration dynamically. Gökçen et al. [23] suggested heuristic procedures and a mathematical model for the multiple or parallel assembly line balancing problem. 120 2011 International Conference on Management and Artificial Intelligence IPEDR vol.6 (2011) © (2011) IACSIT Press, Bali, Indonesia