Manufacturing Ergonomics Research Articles

Effect of ergonomic aspects on single‐ and multiproduct assembly‐line balancing problems

AbstractIncorporating ergonomic considerations into an assembly‐line balancing problem (ALBP) enhances productivity and minimizes ergonomic concerns. The assembly process, characterized by repetitive motions and handling numerous components, can lead to worker overload. Consequently, the inclusion of ergonomic aspects results in an appropriate distribution of assembly operations and relative workloads. This study investigates a multi‐objective ALBP aimed at minimizing the number of workstations, overall skill level required, and variance in workers' energy expenditure across workstations. To address the ALBP while considering the ergonomic aspects, this study proposes an approach based on the non‐dominated sorting genetic algorithm II (NSGA‐II) and multi‐objective simulated annealing (MOSA) using Pareto optimality. A comparative analysis of the NSGA‐II and MOSA is conducted in single‐ and multiproduct production scenarios, and a computational study involving various factors is performed to identify the dominant algorithm. The computational analysis indicates that the runtime performance of MOSA is 73.287% better than that of NSGA‐II; therefore, MOSA outperforms NSGA‐II. This study aims at applying scientific knowledge concerning manufacturing ergonomics to assist manufacturing industries in enhancing their productivity.

An Online Framework for Cognitive Load Assessment in Industrial Tasks

The ongoing trend towards Industry 4.0 has revolutionised ordinary workplaces, profoundly changing the role played by humans in the production chain. Research on ergonomics in industrial settings mainly focuses on reducing the operator's physical fatigue and discomfort to improve throughput and avoid safety hazards. However, as the production complexity increases, the cognitive resources demand and mental workload could compromise the operator's performance and the efficiency of the shop floor workplace. State-of-the-art methods in cognitive science work offline and/or involve bulky equipment hardly deployable in industrial settings. This paper presents a novel method for online assessment of cognitive load in manufacturing, primarily assembly, by detecting patterns in human motion directly from the input images of a stereo camera. Head pose estimation and skeleton tracking are exploited to investigate the workers' attention and assess hyperactivity and unforeseen movements. Pilot experiments suggest that our factor assessment tool provides significant insights into workers' mental workload, even confirmed by correlations with physiological and performance measurements. According to data gathered in this study, a vision-based cognitive load assessment has the potential to be integrated into the development of mechatronic systems for improving cognitive ergonomics in manufacturing.

Development on Meso Ergonomics in Manufacturing Based on Research Trends in The Last Twenty Years

Meso ergonomics continues to develop, research journals on meso ergonomics continue to increase in number, meso ergonomic discussions are carried out ranging from the scope of studies to the application of meso ergonomics in various fields. Macro, meso and micro ergonomics do not yet have clear scope limits, this makes the researchers continue to conduct studies on the limits of meso ergonomic studies. The application of ergonomic science continues to be developed by researchers, during the span of 1997 to 2017 a total of 51 studies on ergonomic meso were carried out, the main focus of the research was carried out in the fields of health, services, manufacturing and other fields. Meso ergonomic research in the field of health as many as 20 studies, 6 services and 12 fields of manufacturing and 13 other fields of research. Most research occurred in the health sector with the most research in 2005 as many as 5 studies, research in the field of health, especially in hospitals consisting of, managerial design and improvement, improvement of hospital services and the impact of managerial policies on nurses. In the field of services, the focus of his research is the managerial system and improvement of the customer’s perspective on services. In manufacturing the focus of the research is to maximize output by taking into account worker fatigue. All fields of ergonomic meso studies will be evaluated because they still have shortcomings and are not credible

An automatic procedure based on virtual ergonomic analysis to promote human-centric manufacturing

Today manufacturing enterprises aim not only to deliver high-value, cost-effectively products in a sustainable way, but also to consider the quality of the working environments. The analysis of human factors, which strongly affect time and quality of manufacturing processes, are crucial for satisfying people involved in the manufacturing process and making them safe, preventing diseases, errors and excessive workload. The paper presents a structured procedure to automatically extract data from virtual analysis made by digital manufacturing tools and measure a set of indicators to validly assess manufacturing ergonomics. The research considers the state of the art in manufacturing ergonomics and defines a set of indicators suitable for manufacturing manual operations, focusing on assembly tasks. Furthermore, it defines a methodology to automatically extract data valorising the selected indicators and an application, based on Visual Basic, to generate the specific task list and related assessment. The result is a rapid and objective assessment, independent from the experience of the user, which can be executed during process design. The procedure has been applied to an industrial case study, where the manual assembly of cabin supports on the tractor chassis has been analysed in order to correct the most uncomfortable steps and obtain a more ergonomic process. A decrease of the EAWS score, calculated with the proposed method, allowed to validate the proposed solution, suggesting a redesign of the assembly cycle to improve the working conditions. Such a procedure anticipates the analysis of the workers’ wellbeing during the design stage to support the definition of human-centric manufacturing processes, simplifying and accelerating the assessment activities.

A comparative study on computer-integrated set-ups to design human-centred manufacturing systems

Manufacturing ergonomics refers to the application of ergonomic principles and human factors analysis to the design of manufacturing tasks with the final aim to optimize the workers’ wellbeing and guarantee the expected process performance. Traditional design approaches are based on the observation of individual workers performing their jobs, the detection of unnatural postures (e.g., bending, twisting, overextending, rotating), and the definition of late corrective actions according to ergonomic guidelines. Recently, computer-integrated simulations based on virtual prototypes and digital human models (DHMs) can be used to assess manufacturing ergonomics on virtual manikins operating in digital workplaces. Such simulations allow validating different design alternatives and optimizing the workstation design before the creation, and pave the way to a new approach to manufacturing system design. The present paper aims at comparing different computer-integrated set-ups to support the design of human-centred manufacturing workstations. It defines a protocol analysis to support workstation design by analysing both physical and cognitive aspects, and applies the protocol within different digital set-ups. In particular, the study investigates a 2D desktop set-up using standardized DHMs and a 3D immersive mixed reality set-up based on motion capture of real workers’ acting into a mixed environment, comparing them with the traditional approach. An industrial case study focusing on design optimization of a manufacturing workstation in the energy industry is used to test the effectiveness of the two digital set-ups for the definition of re-design actions.

ErgoVSM: A Tool for Integrating Value Stream Mapping and Ergonomics in Manufacturing

AbstractValue stream mapping (VSM) is a lean tool aiming at waste reduction. Previous research suggests that the use of VSM may result in work intensification and thus an increased risk for the workers of developing work‐related musculoskeletal disorders (MSD). In the current study, VSM was developed to also consider physical exposure in the analyzed production system (ErgoVSM). As the VSM, ErgoVSM is based on a participatory approach. ErgoVSM was tested in a Swedish manufacturing company. The results suggest that ErgoVSM catalyzes change processes to include intervention proposals emphasizing ergonomics in addition to waste reduction. Thus, ErgoVSM appeared useful for the investigated target group of production engineers and experienced operators. The performance improvements suggested when using the ordinary VSM seemed not to be hampered by adding the ergonomics complement. However, the use of ErgoVSM was somewhat more time consuming than the use of VSM. In conclusion, ErgoVSM is suggested as a feasible tool to be used by production engineers and experienced operators for including ergonomics considerations in the rationalization process.

A pilot study for defining characteristics of Turkish women via anthropometric measurements

The anthropometric characteristics of the Turkish female population are needed for the design of safe and ergonomically efficient workplaces. The purpose of this study was to determine the anthropometric characteristics of the Turkish female population in one region. For this purpose, 56 anthropometric parameters were measured according to ISO 7250. Two hundred and twenty-five Turkish women participants who were aged 18+ years were selected to participate in the study. The measurements were obtained with an anthropometry measuring set. Principal component analysis was used to create statistical models to draw on information from two or more databases to estimate values for a large range of anthropometric variables. A reliability analysis was carried out on survey data to ensure the internal consistency of the constructs. The results of this study showed that the following five factors allow for a good general description of human body shapes for the Turkish female population: "corpulence", "length of body parts", "upper body length", "length of arm" and "hip-thigh region". The data provided by this study can help to solve a wide range of design problems, including product ergonomics and workplace ergonomics in manufacturing.

Innovative system for real-time ergonomic feedback in industrial manufacturing

This work presents a system that permits a real-time ergonomic assessment of manual tasks in an industrial environment. First, a biomechanical model of the upper body has been developed by using inertial sensors placed at different locations on the upper body. Based on this model, a computerized RULA ergonomic assessment was implemented to permit a global risk assessment of musculoskeletal disorders in real-time. Furthermore, local scores were calculated per segment, e.g. the neck region, and gave information on the local risks for musculoskeletal disorders. Visual information was fed back to the user by using a see-through head mounted display. Additional visual highlighting and auditory warnings were provided when some predefined thresholds were exceeded. In a user study (N = 12 participants) a group with the RULA feedback was compared to a control group. Results demonstrate that the real-time ergonomic feedback significantly decreased the outcome of both globally as well as locally hazardous RULA values that are associated with increased risk for musculoskeletal disorders. Task execution time did not differ between groups. The real-time ergonomic tool introduced in this study has the potential to considerably reduce the risk of musculoskeletal disorders in industrial settings. Implications for ergonomics in manufacturing and user feedback modalities are further discussed.

30 Years of Ergonomics at 3M: A Case Study

The added value of the Ergonomics Program at 3M was found to be improved employee safety, compliance with regulations and reduction of work-related illness, increases in productivity, and quality and operating efficiency. This paper describes the thirty years of existence of this program. For the first twenty years, the program objectives were to: respond to requests for assistance related to work-related musculoskeletal disorder (WMSD) concerns, raise employee awareness of MSDs and ergonomics; educate engineers in ergonomics design; and develop ergonomics teams at manufacturing locations. Since the year 2000, 3M's Ergonomics Program has been in transition from a US-centric and corporate-based technical-expertled program to a global program applying participatory ergonomics strategies within a macroergonomics framework. During that transition, the existing program requirements were revised, new methods and program tools were created, and expectations for implementation at the manufacturing locations clarified. This paper focuses on the company's manufacturing ergonomics program activities during the past ten years and includes specifics of the program's objectives, risk assessment reduction process, and ergonomics technical expertise development. The main benefit achieved throughout the company is reducing employee injury while also increasing productivity and operating efficiency.

A note on “Human and Machine Effects in a Just‐In‐Time Scheduling Problem” [Eren, T. (2009). Human Factors and Ergonomics in Manufacturing, 19(4), 294–299

AbstractThe aim of this article is to point out some flaws in the mathematical programming model proposed by Tamer Eren [Human and Machine Effects in a Just‐In‐Time Scheduling Problem, Human Factors and Ergonomics in Manufacturing, 19(4), 294–299 (2009)]. Ignoring these flaws may cause unexpected computational results. © 2010 Wiley Periodicals, Inc.

Retraction: The manufacturing enterprise diagnostic instrument: A tool for assessment of enterprise system manufacturers

The following article from Human Factors and Ergonomics in Manufacturing, “The manufacturing enterprise diagnostic instrument: A tool for assessment of enterprise system manufacturers,” by Ash Genaidy and Waldemar Karwowski, published online on October 11, 2007, in Wiley InterScience (www.interscience.wiley.com) and in the November/December 2007 issue in print, has been retracted by agreement with the Editors, Gavriel Salvendy and Waldemar Karwowski, and Wiley Periodicals, Inc., at the request of the University of Cincinnati after an internal investigation determined that Dr. Genaidy failed to identify co-authors. The article should have been published as Hassan Al-Atat, Ash Genaidy, Richard Shell, Amer Ghanem, David Le, & Waldemar Karwowski (2007), “The manufacturing enterprise diagnostic instrument: A tool for assessment of enterprise system manufacturers.” Human Factors and Ergonomics in Manufacturing, 17, 521–574.

Focus on … The Manufacturing Environment: Control and Ergonomic Considerations: Manufacturing Ergonomics: A Historical Perspective

Abstract Our feature this month offers insights on the issue of ergonomics and controls in the manufacturing environment. Though often viewed from separate perspectives, these concepts are interrelated in the workplace setting. “Manufacturing Ergonomics: A Historical Perspective” by Steven L. Johnson examines this “dynamic specialty” in terms of its development over the years and its current impact on the plant floor. This article was originally published in the Human Factors Society Bulletin, Vol. 32, No. 2, in February 1989. Applied Industrial Hygiene appreciates their permission to share this timely article with our readers. The second segment of our feature was excerpted from Robert J. Firenze's chapter “Occupational Safety” in the Evaluation and Control of the Occupational Environment, published by the National Institute for Occupational Safety and Health. Mr. Firenze's views on administrative and engineering controls are pertinent for both industrial hygiene and safety professionals.