Human Factors Effects on a Human-Robot Collaboration System: A Modelling Approach

This work introduces a system dynamics-based model for designing feedback mechanisms related to the physical and mental workload in Human-Robot Collaboration (HRC) systems. As a dynamic and non-linear system, HRC workplaces challenges ergonomic operations in the medium and long terms, and it is crucial to understand the whole system in order to increase reliability in decision-making about ergonomic interventions. The aim of this paper is to define which variables are to be considered and how they interact to predict the behavior of the HRC system over time. The method applied in the work follows four phases: literature review to systematic search for case studies and theoretical literature embracing the objectives of this work; summary of factors in HRC systems and their relationships obtained through the review of previous studies; definition of variables for the model gathered in a way they became the variables to be modeled; design of the Causal Loop Diagram (CLD) as a qualitative model developed from the variables, which formalizes and delimits the context to be analyzed. This paper proposes the conceptual definition by considering both physical and mental overload as cause of Work-related Musculoskeletal Disorders (WMSD) and influence on productivity. The work shows both subsystems, how they are connected, and reinforce the importance of looking at ergonomic problems with a systemic approach. Modeling the whole system is key to solve ergonomic problems in industry. The qualitative model CLD provided through the literature review is useful in understanding HRC systems.