Session: 02-08-01: Advances in Human Modelling

Paper Number: 142849

142849 - A Comparative Digital Physical Ergonomics Analysis Between Manual and Semi-Automated Manufacturing Operations: Human-Centered Guidelines for Workstations Optimization 

Industry 5.0 is defined by the transformation of industrial processes, which become more and more human-centered. The operator's position in the new connected industrial systems has evolved as a result of the increased automation implemented with the help of information and communication technology, and the introduction of innovative advanced technologies. In this context, determining the operator risk is essential to maintain worker safety and well-being. With this new background, the use of modern monitoring technology that adopts a holistic and objective approach, to assess the operator's ergonomic conditions, becomes compelling.
This work proposes an innovative framework for comprehensive and objective analysis of physical ergonomics of industrial operators. The case study has been implemented in an important company that produces refrigeration systems for commercial and industrial applications. The presented assessment refers to the physical ergonomic analysis for the operations of hook insertion and brazing on heat exchangers. The analysis has been performed combining subjective and objective methods. Self-assessment questionnaires were administered to investigate the working conditions of the operators, and their perception of physical and mental effort during their job’s activities. A semi-structured survey was followed by the User Experience Questionnaire (UEQ), the Body Part Discomfort Scale (BPDS), and the Borg CR10 questionnaire. Among the motion capture systems, the Xsens MVN Awinda system was chosen for its wearable inertial sensors, wireless communication solutions, and advanced fusion algorithms rooted in biomechanical models. In the ongoing study, MVN Awinda captures operators' movements during work tasks, and the acquired data undergoes algorithmic analysis to assess operator ergonomics. For Rapid Upper Limb Assessment (RULA) risk index calculation, Xsens MVN Awinda output files are utilized, specifically focusing on joint angles of upper limbs, trunk, and neck. This enables the calculation of RULA scores for each recorded frame, providing an assessment of the entire work cycle with detailed insights into the duration of high-risk postures. For a deeper comprehension of operator’s ergonomics, the Strain Index (SI) and NIOSH methods have been added to the study. Indeed, while the RULA examines workers' susceptibility to musculoskeletal disorders in the upper limbs, neck and trunk, the SI offers a semi-quantitative assessment of biomechanical overload risk in work involving repetitive upper limb (forearm, wrist, and hand) movements, and the NIOSH equation allows assessing the risks involved in material handling tasks (for loads ≥ 3kg).
The study has been set up as a comparative analysis between the manual operations (performed by two different operators, one for the hook insertion and one for the hook brazing) and the semi-automated ones (i.e., the interaction between a third operator and the cobot that inserts and welds the hooks).
Preliminary results show halved times with high risk activities for both hook insertion and brazing in the semi-automated case. Also, the time spent with medium risk activities for brazing is twofold in the manual case than the automated one. Overall, it is possible to observe an increase in time at low or negligible risk in the semi-automated case.
The company intends to leave in and optimize the manual workstations, and, at the same time, introduce a new, optimized, and redesigned cobot to insert and braze the hooks. For this reason, based on the digital ergonomic analyses, this study proposes some preliminary guidelines for the manual and semi-automated workstations re-design, following the human-centered design principles. Future work will involve objective cognitive ergonomics analysis, and will include human factors in the product and process re-design.

Presenting Author: Agnese Brunzini Università Politecnica delle Marche

Presenting Author Biography: Agnese Brunzini is a biomedical engineer with a Ph.D. in industrial engineering. She works as research fellow at Università Politecnica delle Marche, Department of Industrial Engineering and Mathematical Sciences.

Authors:

Agnese Brunzini Università Politecnica delle Marche
Filippo Maria Micucci Università Politecnica delle Marche
Marianna Ciccarelli Università Politecnica delle Marche
Alessandra Papetti Università Politecnica delle Marche
Michele Germani Università Politecnica delle Marche