A Simulated Annealing Approach for Scheduling of non-independent Jobs on FSPM

In the past years, flexible production systems have allowed an extensive exploitation of new technologies, but have also led new difficulties in production planning management science. The model presented in this paper extends the traditional FSPM (Flow Shop with Parallel Machines) scheduling problem to the case in which (1) the machines at a certain stage are parallel and identical but not undistinguishable in terms of job assignment, (2) the jobs are partially related by precedence constraints and batch assignment constraints and (3) the parallel machines at a stage are served by a bottleneck machine according to a round robin discipline. A hybrid scheduling approach is proposed, based on the integration of simulation modelling with the well-known simulated annealing approach. A design procedure, based on the response surface methodology, is exploited to specify the parameter set for the simulated annealing algorithm. An industrial test case is provided, which proves the effectiveness of the proposed approach.