Model-Based Hazard an Propagation Assessment of Product Changes

Abstract

The current markets are characterized by an increasing demand for individual products, increasing product complexity and stricter safety regulations. This results in large hazard and safety analysis efforts for each individual product variant. One possible solution to reduce these efforts is the automation of analyses and a preliminary assessment of individual changes. Therefore, several approaches are published to e.g. model safety aspects or evaluate change propagations. However, the approaches fail to directly establish the connection between product changes and safety aspects by a common model. This paper develops a method to identify and assess the potential hazard impact of product changes through a common static model. It builds on a graph-based product model and graph-rewriting. From the state of the art, suitable methods tools and principles are identified and evaluated. Based on this, requirements are derived. The capabilities of existing methods are assessed and the most suitable ones adapted and integrated to the method to assess the potential hazard impact of product changes (MBHPA). The MBHPA reduces the complexity by providing two independent interconnected analyses. To evaluate the product changes, a static propagation analysis is provided. It uses defined graph-rewriting patterns to trace propagations and extract a propagation tree. The affected components in a second step can then be evaluated on their hazard potential. Again graph-rewriting patterns are applied to identify the connected hazards which are visualized in a hazard potential portfolio. The MBHPA is implemented and evaluated with the industrial case of an automated coffee machine. The evaluation underlines that the MBHPA successfully identifies possible propagations and their effect on hazards from a static perspective. It helps to improve safety awareness and traceability and reduces the required experience.