Franziska Wieja

The development of patient-specific medical systems poses challenges for requirements engineering and their traceable integration into system models, as regulatory frameworks require transparent and traceable links between stakeholder needs and product requirements. Document-based approaches lack the formal structure required to derive verifiable product requirements and integrate patient-individual parameters into testing processes. This study investigates how Model-Based Systems Engineering (MBSE) can formalize user needs, user requirements, and patient context parameters to enable a traceable, model-based testing of patient-specific systems. A SysML-based formalization approach is developed that extends the motego method. New stereotypes for user needs and user requirements are introduced and linked via SysML relations to stakeholders, use scenarios, and product requirements. A patient context model is proposed to represent patient-individual parameters and integrate them into a model-based test framework. The approach is demonstrated using an exemplary use case by instantiating representative user needs, user requirements, and patient context parameters and linking them to functions, solutions, and domain model elements within the test framework. An exemplary use case demonstrates the integration and transfer of context parameters. The results show a traceable chain between stakeholders and product requirements, as well as the consistent transfer of context parameters into domain model elements. The simulation is used exclusively as an executable component to demonstrate data integration and model consistency; no validation of physical accuracy is performed.

Technical folding systems are rigid, three-dimensional surface structures that can be folded at their joints. Due to their foldable structure, technical folding systems can produce lightweight structures that have a high load-bearing capacity and can also flexibly change their shape. In order to develop products with technical folding in a function-oriented product development process, a folding principle must be defined that realises the individual functions. Since there is hardly any expert knowledge on technical folding, in general, and on the use of the technical folding principle in particular, technical folding is not very widespread despite its promising properties. Therefore, there is a need for a software-supported evaluation of whether functions can be realised by the principle of technical folding. The software-supported applicability evaluation (EvalTech) developed here is based on case-based reasoning methods, as these can artificially simulate evaluations based on expert knowledge. The expert knowledge used for the evaluation includes functions, function structures and properties of known technical folding systems, which are compared with functions and function structures of the development task. EvalTech was successfully used in the development and realisation of a large-scale foldable cover for industrial robots.