Makespan Optimization in Open Shop Scheduling

In today’s rapid production scenario, scheduling plays a dynamic role in planning. In this work, open shop scheduling problem related to a copper flexible braids manufacturing company is considered. In a scheduling problem, the purpose is to find the orders of jobs on specific machines with an objective to optimize the makespan. Scheduling can be either manual or automatic. Manual scheduling of operations is a difficult task. Hence, computational methods are used to automate and simplify the process. In this work, integer programming and constraint programming-based mathematical models are developed to tackle this problem. The branch-and-bound (B&B) algorithm is applied for integer programming model, and branch-and-cut (B&C) algorithm is applied for constraint programming model in order to get optimized makespan. A comparison of results obtained from both mathematical models is done for selection of optimized makespan and identification of model.