Mathematical Modeling of Energy-efficient Integration of Process Planning and Scheduling

Abstract

Process planning and scheduling are two main parts of the discrete manufacturing workshops, and integrating these two parts will help to increase production efficiency and reduce energy consumption. The integration of process planning and scheduling (IPPS) problem with the objective of minimizing energy consumption is studied. Three mixed integer linear programming (MILP) models that consider turning Off \On strategy are proposed based on two different modeling ideas namely idle time and idle energy. These three models are compared and evaluated detailedly under both the size and computational complexities. The correctness and effectiveness of the proposed models are verified by using CPLEX solver to solve the instances of IPPS. The experimental results show that the MILP models based on different modeling ideas are very different in both the size and computational complexities. The model based on the modeling idea of idle energy is better than the models based on the modeling idea of idle time.