Using fuzzy logic approach to predict work-related musculoskeletal disorders among automotive assembly workers

Background: Musculoskeletal disorders (MSDs) are considered an important health concern, particularly in automotive assembly industries. Evaluation of the effects of all MSDs risk factors is difficult due to its multifactorial nature. In addition, the risk factors cannot be detected accurately when they are only based on individual opinions. Thus, in this study, fuzzy logic tool was used to evaluate the combined effects of all risk factors on MSDs. Methods: This cross sectional study was conducted on 100 male workers in an automotive industry. Job satisfaction, job stress, job fatigue, and body posture were evaluated by a self-reported questionnaire. Body posture was evaluated using Rapid Entire Body Assessment (REBA). Primary data analysis on extracting the input variables of MATLAB was performed by SPSS 22, with a significant level of 0.05. T test, one-way Anova, and Pearson correlation analysis were used to extract the input variables for the fuzzy logic model. The results obtained from the Nordic questionnaire was selected as the output of the fuzzy model. Fuzzy logic assessment was performed using MATLAB software version 7.0. Results: There were significant differences between WMSDs factors, including job fatigue, strain, working posture, and the REBA final score, and pain in all limbs of the body (p<0.05). A significant difference was also found between working posture with wrist score (p<0.05). The findings on defuzzification showed a strong correlation between real and modelling results. Conclusion: The results showed that many factors such as posture, fatigue, and strain affect MSDs. Based on the obtained results, all categories of risk factors, including personal, psychosocial, and occupational, should be considered to predict MSDs, which can be achieved by a modeling approach. Keywords: Automotive industry; Fuzzy logic; Work-related musculoskeletal disorders

Design Work Station Of Pipe Welding With Ergonomic Approach

The activity of welding specimens on a big pipe that causes various problems for the body, in this activity the worker is at a risky position such as lifting a pipe weight 90 kg, lifting the specimen and welding the pipe with the specimen and the final process is to lower the pipe that has been connected. The purpose of this study is to design workstation by the principles of ergonomics to help reduce physical worker complaints. The research method in this study was the Nordic Body Map (NBM) questionnaire to determine complaints of musculoskeletal disorders (MSDs); the work posture was analyzed by the Rapid Entire Body Assessment (REBA) method. From the results of this study, it can be concluded that the welding work requires a tool in the form of a bench, pipe support, a pulley used at a new welding workstation. With a new workstation, poor work posture can be repaired. With a new work station, there is an efficiency of 8.33 minutes of work time from previous working conditions

Analytic hierarchy process and knowledge-based system integration for web-based ergonomics assessment approach in prioritizing workplace critical risk factors

Conducting workplace ergonomics risk assessment is a legal obligation for all workplaces, including automotive manufacturing plant. The needs for a competent ergonomist to study, design, and evaluate human work system is crucial. Thus, utilizing the technology of knowledge-based system (KBS) in ergonomics makes it possible for an ordinary worker to use ergonomic experts' expertise to accomplish their work accurately and efficiently without experts' assistance. This thesis presents a web-based ergonomics assessment system (W-BEAS) to evaluate and prioritize automotive workplace risks. The study's methodology under phase 1 starts with investigating dominant ergonomics risk factors in the workplace. In the preliminary study, 97 questionnaires were collected out of 120 sets to identify workplace ergonomics' performance, and the improvements demand at an automotive production plant. Under phase 1, the study continues with several methods: MSD symptom investigation, job task assessment, established studies review, domain expert knowledge analysis, and risk factors validation. Then, this study continued with establishing the analytical hierarchy process (AHP) based assessment method for prioritizing the critical ergonomic risk factors. Finally, a web-based ergonomics assessment system (W-BEAS) was developed by integrating the AHP technique, KBS, and web-based approach to evaluate automotive workplace hazards elements. The W-BEAS was developed using XAMMP software by integrating a KBS, the AHP technique and a web server that users can access from any device with an internet connection. Apache's XAMPP software is a cross-platform web-server solution stack that is free and open-source. The preliminary study results showed that about 70% of the respondents observed that employees frequently complained about their job task, and 60% or more of the respondents understood a need to improve their workplace. The investigation process for ergonomics risk factors has produced 26 dominant risk factors stored as knowledge-based for W-BEAS databased. The AHP-based evaluation method identified the organizational ergonomics are the most critical factor that leads to WMSD development in the vehicle component manufacturing plant. The critical sub-risk factors, including the level of education, physical demand at work, force exertion in job task, hand-arm vibration and low job support. The AHP-based evaluation method has validated by the consistency judgement (CR 0.05). The W-BEAS's ability to assess workplace ergonomics risk factors is recognized, and ordinary workers could assess their workplace situations using the website. Therefore, W-BEAS is significant in the automotive industry that allows ergonomics risk information to be accessed and studied at the earliest stages of product and process design

An observational method for Postural Ergonomic Risk Assessment (PERA)

Monotonous, repetitive work characterizes production lines. Repetitive movements and awkward postures are the most prominent physical risk factors in the workplace. Various legislations have been enacted along with technical standards for ergonomic risk evaluation to ensure the safety of the operators. There are numerous methods to assess the ergonomic risk at work. However, most methods are not meant to be used for assessing cyclic work. This paper proposes a method, Postural Ergonomic Risk Assessment (PERA), which is suitable to evaluate the postural ergonomic risk of short cyclic assembly work. Its key features are simplicity and compliance with standards. The added value of the method is that it provides an analysis of every work task in the work cycle, which facilitates the identification of sources of high risk to the operator. The method has been verified on nine work cycles, constituted by 88 work tasks, and it demonstrates accordance with the European Assembly Worksheet (EAWS), which has been developed to comply with the relevant standards and is one of the most comprehensive tools for ergonomic risk assessment. Industrial relevance: The simplicity and the compliance with standards of the proposed method would allow for a quick check of every work task of the work cycle and identification of problem areas. With further work, it would be possible to integrate the method along with work design tools used in the industry

Workplace wellbeing programmes and their impact on employees and their employing organisations: a scoping review of the evidence base

This report constitutes a scoping literature review that identifies and critically examines the evidence base surrounding health and wellbeing programmes conducted in the workplace and their impact on employees and their employing organisations. The review drew on a broad range of sources covering multiple sectors. However, the report additionally highlights evidence that relates specifically to the retail and construction industries. The review offers an analysis of the current evidence base and discusses the implications of implementing different types of workplace health and wellbeing schemes. Some recommendations for supporting and promoting the health and wellbeing of employees in organisations are made on the basis of this review and, where gaps in knowledge are identified, recommendations for further research are made

The potential of Quality Function Deployment (QFD) in reducing work-related musculoskeletal disorders

Musculoskeletal disorders (MSDs) frequently affect the health and well-being of workers and can hinder growth in the industrial sector. Research indicates that user requirements to reduce workplace risk factors for MSDs are not always effectively conveyed to practitioners of design. This creates a mismatch between these requirements and what is ultimately produced. Quality function deployment (QFD) is a structured collaborative design approach, widely used in industry. The aim of this research was to explore the potential of a QFD-based design tool to enhance such communication in the design process and help reduce work-related MSDs. In order to evaluate user knowledge and ability to identify workplace risks and the subsequent requirements for design, a multi-methods study was undertaken with cleaners (n= 10), joiners (n= 6) and plumbers (n= 6) and their line managers (n= 6). Methods included semi-structured interviews, task analysis, REBA and body part discomfort maps. The findings revealed that these workers were in general able to identify risks to their musculoskeletal health and make design suggestions related to specific tasks. All of the workers expressed concern about manual handling, and issues related to awkward postures were also identified by the majority. A QFD-based design tool (with guidance material) was then developed to facilitate communication in the design process. It consisted of six features to encompass the design process, and included tools and techniques with supplementary templates to aid practitioners. In order to evaluate its feasibility with respect to current practice, an online questionnaire survey was conducted with a cohort of practitioners of ergonomics and design (n= 32). Of these, the majority rated highly the importance of an integrated approach for participatory design to help reduce work-related MSDs. They also suggested elements to be included in the design tool, which were in congruence with the features already included. To evaluate the strengths and weaknesses of the design tool in the field setting, in-depth interviews using a walkthrough approach (n= 8) and case studies of specific work tasks (n= 3) were conducted with practitioners. The findings showed that the design tool would be very useful in managing and presenting design information. In particular, practitioners liked being provided with design principles to help systematically identify design solutions to reduce risks and using the QFD-based matrices to present such information. Limitations of the tool were identified as inadequacy of guidance, the lack of automated procedures and the time required to set up and learn. The design tool (and guidance material) seems to have potential in facilitating the sharing of design information among the stakeholders of the design process

Towards a uniform definition for the centralisation phenomenon

The focus of this PhD project is on symptom centralisation. Its primary objectives were to establish a standard operational definition of centralisation and evaluate its inter-rater reliability in neck pain. Two systematic reviews on the reliability and prognostic value of clinically induced symptom responses in spinal pain (Chapters 2 and 3) showed that although the potential usefulness of centralisation has been demonstrated in low back pain, concern has been expressed about the observed inconsistency in reported definitions, and the scarcity of studies in neck pain. A Delphi survey of experts (Chapter 4) assisted in the development of a uniform operational definition for centralisation and the identification of future research questions. Centralisation was generally defined as the progressive and stable reduction of the most distal presenting pain towards the spine midline in response to standardised spinal loading strategies. The support by the Delphi panel of a broader definition allowed for a multitude of different ways of testing to be included in the assessment procedure which may offer some flexibility to clinicians assessing, classifying and managing different spinal pain presentations across different countries. Although the reliability of identifying centralisation was acceptable, high levels of reliability were not demonstrated (Chapter 5). However, reliability was greater for the pair of physiotherapists with prior experience and formal extensive training in symptom response assessment. Therefore, the optimal type and amount of training for eliciting and interpreting centralisation and the effect of procedural variations on testing the outcomes of individuals who centralise require urgent investigation. The prognostic and management value of centralisation are also unknown. This investigation may pave the way for the standardisation of centralisation as a physical sign and stimulate interest for further study of potential sub-groups and classification of spinal syndromes