Worker Job Rotation Optimization Model to Minimize Exposure to Hand-Arm Vibration

Recently, job rotation scheduling models have received an increasing attention because of their ability to find optimal solutions and minimize the risk of development of different occupational diseases in manufacturing environments. Hand-arm vibration (HAV) is one of the major ergonomic risks that leads to serious health problems or injuries in the neurological and musculoskeletal systems of the hand-arm part of the body. In this work, A model based on mixed integer linear programming (MILP) has been created to enhance the ergonomic aspects of the manufacturing environment. The objective of the model is to minimize the daily vibration exposure for all employees when allocating the tasks. The developed model has been implemented and solved in the solver GAMS using real-world data gathered from a metal manufacturing facility. All HAV exposure values were kept under legal limit (5 m/s2). The highest HAV exposure value was 4.45 m/s2 and the lowest was 2.39 m/s2 during the scheduling plan.