Abstract
The traditional assembly line which produces a single-model product is not efficient for today's competitive industry and it cannot respond the customers' expectations. This drives companies toward multi/mixed-model products. In addition, the assembly lines' layout is of great importance for realizing such products and achieving the expected productivity improvement and capacity increase. In the current industrial context integration of Collaborative Robots (Cobots) in the assembly lines can be considered an effective way to increase the productivity while ensuring job security and flexibility. Thus, this study proposes a new Multi-Product Separated Line Collaborative Assembly Line Ba lancing Problem (MPSLC-ALBP) mathematical model to optimize resource assignment among lines. Besides the multi-product aspect, comparing to traditional ALB, the proposed model embraces the particular scenarios of Human and Cobot interaction as well as the diversity of workers such as experience level and its impact on task completion times. Through an illustrative case, it is shown that integrated resource optimization for all lines is more beneficial than individual resource optimization. Moreover, the effect of integrated resource optimization will be significant in the case that there are a limi ted number of resources available.