Algorithms for sequencing mixed models on an assembly line in a JIT production system

In many mixed-model assembly lines in just-in-time (JIT) production systems, workers have the power and the responsibility to stop the conveyor whenever they fail to complete their operations within their work zones. Therefore, the conveyor stoppage in a sequencing problem should be taken into consideration. In this paper, two algorithms are proposed for finding an optimal or sub-optimal sequence of mixed models that minimizes the total conveyor stoppage time. The branch-and-bound method is devoted to find an optimal solution for small sized problems, while the simulated annealing method is used to cope with large scale problems to obtain a good sub-optimal solution. A numerical example of a 14 model problem shows that the simulated annealing algorithm is about 100 times faster than the branch-and-bound algorithm to find an optimal solution.