Search

For many years, the Association of German Engineers (VDI) has been issuing guidelines for simulating production and logistics systems as well as for Digital Factory tools. The target group encompasses experts from science, consulting institutions, industrial companies, interest groups and software houses. The guidelines represent the state of the art, but in individual cases can also be regarded as a preliminary stage of a standard. This opens up the possibility of publication without the topic already being viewed as capable of being standardized. An individual guideline can contain several guideline parts. In simulation software and Digital Factory tools, the working human is playing an increasing role. From this background, special guideline parts have already been published, which deal with the modeling of humans in production-logistic simulation and with ergonomic aspects in the Digital Factory. The last-mentioned guideline part deals with the work task and especially with related anthropometric and work-physiological aspects. A further guideline part is currently in the process of being published and regards the stresses and strains from the work environment. This guideline part with its close relation to Occupational Health and Safety is discussed in the following. It reveals that a large field of research and development issues still needs to be clarified in order to integrate these aspects into Digital Factory tools.

In the shipping division of a tinplate manufacturer, alternatives of assigning employees to activities should be examined: a personnel structure where an employee can perform any job or just one type of activity (universalists versus specialists). The aim of the first project stage was to check whether the actual situation can be improved by further qualification measures. A simulation model was developed to analyze different qualifications of the employees and load scenarios of the shipping division. Various difficulties arose due to different shipping materials (coils with horizontal or vertical axis, and panels) and different types of loading (truck, wagon, ship, container). Furthermore, modeling was hampered by fuzzy descriptions of work processes and the lack of time data. For these reasons, the model had to simplify reality. After validating the simulation model based on historical order data, predicted load scenarios were then assumed for the actual investigation. The deployment of specialists led to only minor deterioration in wagon and truck loading, and on the other hand, the lead times of ship and container loading were reduced. However, the universalists approach was accompanied by an increase in lead times for all types of shipping. Therefore, the recommendation was derived to work towards a stronger specialization in future personnel development. In a second project stage, the influence of working time systems on employees’ work-life balance was examined. The statistical analysis showed different effects with regard to the target criteria, but the results were only valid for the regarded shipping division.

In the context of production logistics, U-shaped assembly systems often present several advantages compared to straight-line systems. Therefore, such systems are usually evaluated in the planning phase using production logistics and cost-related criteria. However, some published papers illustrate that these advantages may face ergonomic drawbacks. For decision making, the evaluation must be expanded in order to consider these systems from both perspectives. In this way, unfavorable forms of work organization in U-shaped assembly systems can be detected already during the planning phase. In addition, the static methods such as spreadsheet calculations generally used for planning prove to be poorly applicable due to the overly optimistic results they generate, especially in case of model-mix systems. These aspects are especially addressed here and the difference between static and dynamic approaches are illustrated. Consequently, planning solutions must be validated dynamically by means of simulation. Only then can be judged whether the planned production logistics criteria are achievable at all. In addition, the simulation allows for more realistic statements also concerning ergonomic criteria. This approach will be demonstrated here by a near-to-reality planning case. For a comprehensive multi-criteria decision making in the face of production logistics and ergonomics the use of lexicographic ordering is shown.