APPLICATION OF MIXED-INTEGER LINEAR PROGRAMMING AND BACKWARD SCHEDULING TO REDUCE WASTE OF OPERATOR MOVEMENT

This paper presents a case study of a manufacturing company that aimed to improve the productivity of operators of the Injection Department, which is at the beginning of the production process. Efforts were directed toward optimizing the sequence of machine visits for each operator. This was achieved by applying a mixed-integer linear programming model and backward scheduling to minimize movement waste during the sequence. A preliminary analysis of the current situation was conducted to identify the tasks and movements they perform during their working hours, conduct a time and motion study, and collect data on machine autonomy. Throughout this process, various actions were implemented to address inefficiencies. These efforts led to accomplishing the target values for key performance indicators and reduced approximately 56% in the time spent moving between machines.