The assembly line balancing and schedulingproblem with sequence-dependent setup times:Problem extension, model formulation andefficient heuristics

Assembly line balancing problems (ALBP) consist of distributing the total workload for manufacturing any unit of the productsto be assembled among the work stations along a manufacturing line as used in the automotive or the electronics industries.Usually, it is assumed in research papers that, within each station, tasks can be executed in an arbitrary precedence-feasiblesequence without changing station times. In practice, however, the task sequence may influence the station time considerablyas sequence-dependent setups (e.g., walking distances, tool changes, withdrawal of parts from material boxes) have to beconsidered. Including this aspect leads to a joint balancing and scheduling problem, which we call SUALBSP (setup assemblyline balancing and scheduling problem). In this paper, we modify the problem by modeling setups more realistically, givea new, more compact mathematical model formulation and develop effective heuristic solution procedures. Computationalexperiments based on existing and new data sets indicate that the new procedures outperform formerly proposed heuristics andare able to solve problem instances of real-world size with small deviations from optimality in short time....