Mixed-model assembly line balancing in assemble-to-order environment with considering express parallel line: problem definition and solution procedure

Abstract

Flexibility in product mix and in promise date to customers are two traits which companies have to attain in order to stay powerfully in modern competitive market. This article proposes a particular parallel mixed-model assembly line balancing problem in an assemble-to-order environment for the first time. One of the lines works in conventional condition, the other one works faster and both of them produce similar products. The mixed-model assembly lines are useful to have varied and flexible products and also considering assemble-to-order environment enables companies to have higher flexibility in product mix and lead time (promise date). In this regard, a mathematical model that reflects real-world assembly line condition is developed for the problem. A hybrid genetic algorithm which minimises the weighted cycle time is proposed to solve such a complex problem. Finally, the proposed solution approach is implemented to solve a case study reflecting actual industry environment.