The Mixed Model Sequencing Problem

Mixed model assembly lines are production flow lines that are used to produce a variety of customized products in a cost efficient mass production environment. An example for a mixed model assembly line is a car manufacturing plant that follows a make to order production approach. In order to keep costs down, manufacturers utilize the flexibility that is available in the flow mass production environment to produce different unique products in an intermixed manner on the same line. After achieving a line balance (a long term problem) by assigning different assembly tasks to stations, the short-term problem of sequencing the desired products on the production line needs to be solved. The solution answers the question of how to sequence the different unique model orders the manufacturer receives for production in a production run. Different production sequences will incur different costs that are related to worker utilization or material usage. The objective of this research is to develop an algorithm to solve the Mixed Model Sequencing (MMS) problem. First the mathematical model will be built based on the assumptions and policies chosen. Then an algorithm is developed to exploit the structure of the problem and solve it in an efficient way. Data sets from the literature will be used in the computational experiments to assess the efficiency of the proposed algorithm