Assembly lines have been widely used in various production systems to produce high-volume standardized products. This kind of production lines includes a series of workstations arranged along a material handling system. The components are processed as specified by a set of
tasks, for a given cycle time. Tasks are assigned to an ordered sequence of workstations in accordance with given precedence relationships among them. The problem of assigning tasks to workstations in order to optimize a specific objective, such as minimizing the number of workstations for a given cycle time, minimizing the cycle time for a given number of workstations, or maximizing the efficiency of the assembly line subject to the precedence relationships among tasks, is called the Assembly Line Balancing (ALB)
problem (Sury (1971)). Traditional assembly line balancing research focuses on the modelling and solving the Simple Assembly Line Balancing Problem (SALBP), which has several features such as mass-production of one homogeneous product, pacedline with fixed cycle time, serial line layout within singlemanned workstations, etc. Detailed reviews of such studies are given by Becker and Scholl (2006) and more recently by Battaia and Dolgui (2013) and Sivasankaran and Shahabudeen (2014). However, the assumptions of SALBP are very restrictive and its model might not represent the industrial reality. In recent years, most of researchers tried to model more realistic and generalized problems of the assembly line balancing. The literature contains additional characteristics such as cost functions, mixed-model pro