The cyclic lot scheduling problem with sequence-dependent setups

This paper formulates the cyclic lot scheduling problem on a single facility with sequence-dependent setup costs and times and provides a heuristic solution procedure. A Lagrangian relaxation of the formulation leads to a partial separation of the embedded lot sizing and traveling salesman problems. The relaxation results in a new combinatorial problem related to the minimum spanning tree problem. The information about frequency of production, gained from the solution to this relaxation, is used to find heuristic solutions for the entire problem. Computational work on randomly generated problems show that the problem becomes more difficult as the diversity in the sequence-dependent parameters increases.