Modelling job rotation in manufacturing systems with aged workers

TLDR

The rising retirement age in Europe makes repetitive manufacturing tasks increasingly hazardous for older workers, who are more prone to musculoskeletal disorders, yet their accumulated expertise remains valuable. This study aims to schedule activities by simultaneously matching workers’ abilities to workstation demands and minimizing ergonomic risk through dynamic assignment during shifts. A bi‑objective mathematical model employing a person‑job fit approach evaluates workers’ physical, cognitive, and relational capacities against workstation requirements to generate optimal assignments. Applied to an industrial case, the model demonstrates feasible implementation and improves ergonomics and overall efficiency.

Abstract

The increasing trend of retirement age in Europe represents a critical phenomenon for manufacturing and material handling activities, where repetitive activities, involving the handling of different loads at various frequencies, are usually required. These tasks can lead to occupational diseases and work-related musculoskeletal disorders, which can affect more heavily older workers, due to their decreased functional and physical capacities. On the other side, older workers positively contribute to the manufacturing processes through their expertise and their skills developed over time. This paper introduces a bi-objective mathematical model useful to assign different workers exposed to the risk of repetitive work to various workstations. A person-job fit approach is proposed, which analyses the workers’ physical capacities, competencies and mental and relational skills together with the requirements of each workstation in terms of capabilities and ergonomic load. The aim is to define the activities scheduling through two objectives: the first one considering the matches among workers abilities and workstations activities, the second one reducing the ergonomic risk of repetitive work by varying the assignments during the work shift. The method is also applied to an industrial case, whose results show its applicability and potential benefits, in terms of ergonomics and overall efficiency improvement.