Multi-objective flow shop scheduling using hybrid simulated annealing

Purpose - In order to achieve excellence in manufacturing, goals like lean, economic and quality production with enhanced productivity play a crucial role in this competitive environment. It also necessitates major improvements in generally three primary technical areas: variation reduction, equipment reliability, and production scheduling. Complexity of the real world scheduling problems also increases with interactive multiple decision-making criteria. This paper aims to deal with multi-objective flow shop scheduling problems, including sequence dependent set up time (SDST). The paper also aims to consider the objective of minimizing the weighted sum of total weighted tardiness, total weighted earliness and makespan simultaneously. It proposes a new heuristic-based hybrid simulated annealing (HSA) for near optimal solutions in a reasonable time. Design/methodology/approach - Six modified NEH's based HSA algorithms are proposed for efficient scheduling of jobs in a multi-objective SDST flow shop. Problems of up to 200 jobs and 20 machines are tested by the proposed HSA and a defined relative percentage improvement index is used for analysis and comparison of different MNEH's based hybrid simulated annealing algorithms. Findings - From the results, it has been derived that performance of SA_EWDD (NEH) up to ten machines' problems, and SA_EPWDD (NEH) up to 20 machines' problems, were better over others especially for large sized SDST flow shop scheduling problems for the considered multi-objective fitness function. Originality/value - HSA and multi-objective decision making proposed in the present work is a modified approach in the area of SDST flow shop scheduling.