Identification of the dependence between local muscle load and the method of predetermined times

Abstract: In industrial practice today, the focus is mainly on production automation, big data and smart things. But processes that can't be automated yet are being forgotten. These are manual assembly operations. In the world of assembly, it is still not possible to replace all manual activities appropriately with automation. For this reason, too, there is still a need to address standard setting. However, performance has long since ceased to be the only factor considered by industrial companies. As important as it is to ensure that workers are as productive as possible and that the resulting revenue is maximized. However, the health of the workforce itself cannot be ignored.In order to achieve optimal results, it is necessary to constantly link performance and workers' health. This thesis will examine precisely the link between rationalization and ergonomics or between the setting of standards, worker movements, and potential worker overload. Specifically, it focuses on finding the link between ergonomics and norming or finding the link between local muscle loading and the pre-set time method. The contribution of this work is to detect bad movements at the design stage of a new workplace, as well as to detect dangerous movements in real production without EMG measurements.The evaluation and selection of a suitable measurement tool is the result of the research part. After studying the literature and articles that deal with ergonomics, a measuring instrument for measuring local muscle strain using electromyography will be used for the dissertation research. In the Czech Republic, there is only one measuring device, which is: EMG Holter from Geta. The data collection is oriented toward workers in assembly companies within the Czech Republic, therefore the EMG Holter will be used. Due to the research conducted and literature studied, it was found that the most common occupational disease is upper limb disorders, which are caused by overuse and repetitive movements. Carpal tunnel syndrome has been the most common occupational disease in the Czech Republic for several years. The issue of local muscle strain is nowadays very much addressed. In the Czech Republic, the local muscle load is measured on the forearms of the upper limbs (flexor, extensor). The only legally approved device is the EMG Holter from Geta. The review of scientific articles focused mainly on the issue of norming, with a detailed focus on the MOST method (Maynard Operation Sequence Technique) and its connection with ergonomics. Subsequently, the field of integrated electromyography was explored, especially the measurement of local muscle loading on the upper forearm. Due to the very small sample of papers found on the topic of the link between the MOST method and ergonomics in general, it was found that a very small number of authors had dedicated their research to this topic. However, the models found did not include a link to any norming method focusing on local muscle loading. The aim of this thesis is Identification of the relationship between local muscle loading and the pre-set time method. Within this thesis, I will discuss the MOST (Maynard Operation Sequence Technique) or the method of analysing movement patterns. In order to understand the aforementioned link, it is necessary to create a database of at-risk movements and relate these movements to the MOST method.

Keywords: Ergonomics, MOST, EMG

DOI: 10.54941/ahfe1001580

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