Forces: A Motion Capture-Based Ergonomic Method for the Today’s World

Abstract

Approximately three of every five workers are affected by musculoskeletal disorders, especially in production environments. In this regard, workstation ergonomic evaluations are especially beneficial for conducting preventive actions. Nevertheless, today’s context demonstrates that traditional ergonomic methods should lead to smart ergonomic methods. This document introduces the Forces ergonomic method, designed considering the possibilities of inertial motion capture technology and its applicability to evaluating actual workstations. This method calculates the joint risks for each posture and provides the total risk for the assessed workstation. In this calculation, Forces uses postural measurement and a kinetic estimation of all forces and torques that the joints support during movement. This paper details the method’s fundamentals to achieve structural validity, demonstrating that all parts that compose it are logical and well-founded. This method aims to aid prevention technicians in focusing on what matters: making decisions to improve workers’ health. Likewise, it aims to answer the current industry needs and reduce musculoskeletal disorders caused by repetitive tasks and lower the social, economic, and productivity losses that such disorders entail.

Ergonomics Evaluation Using Motion Capture Technology—Literature Review

“…The information self-reported by employees provides a distorted picture and observation or self-report methods suffer from low reliability, repeatability, and subjectivity (Baber and Young [32]). According to Marin and Marin [31], there is an increasing demand in Industry 4.0 to update these observation methods and strive for Ergonomics 4.0 or smart ergonomic processes.…”

“…Ergonomists have been using various observational methods or classifications for a long time, for example: for repetitive work-Occupational Repetitive Action (OCRA), for load handling-National Institute for Occupational Safety and Health (NIOSH) equation, and, for postural load assessment or other methods-Rapid Entire Body Assessment (REBA), Rapid Upper Limb Assessment (RULA), or Ovako Work Analysis System (OWAS). These methods are useful in industrial environments as they do not require too much equipment [31,32]. However, for example, RULA measurements based on self-report by workers or observation by an external assessor are subjective and suffer from low repeatability [30].…”

“…However, for example, RULA measurements based on self-report by workers or observation by an external assessor are subjective and suffer from low repeatability [30]. The current context of Industry 4.0 focuses on the importance of updating these observational methods and the necessity to develop and implement new objective ergonomic assessment methods [31]. For this reason, there is a growing interest in reliable, fast, and automatic tools for motion capture and analysis, not only in industrial environments, but also in the entertainment, medical, and sports fields [33].…”

Ergonomic human-robot collaboration in industry: A review

“…Camera-based systems with infrared (IR) cameras can be used to triangulate the location of retroreflective rigid bodies (markers) attached to the targeted subject ( Nagymáté and Kiss, 2018 ; Chatzitofis et al, 2021 ; Hu et al, 2021 ). In addition, systems based on inertial measurement units (IMU) that track the relative movements of articulated structures have become popular for their versatility ( Vignais et al, 2013 ; Caputo et al, 2018 ; Marín and Marín, 2021 ). Moreover, at the time of writing, markerless optical MoCap systems undergo significant research progress with high application potential.…”