We are proud to announce the release of version 2.0 of our safety modeling tool safeTbox™. In this version, the following capabilities have been added:
Modeling capabilities
Goal Structuring Notation (GSN)
Create structured and modular safety arguments with the well-known GSN modeling technique. You can use it to create process-related argumentation, such as safety cases, as well as product-specific arguments, such as safety concepts. Moreover, you can easily create references/traces to other model constructs (e.g., UML/SysML blocks, components, ports, fault trees, …). Traceability is supported in an efficient manner by a customizable auto-completion user interface suggesting elements based on the current word written.
Failure type systems for Fault Tree Analysis
Typical failure type classifications, such as the guide words defined in the Hazard and Operability Study (HAZOP), are very helpful during safety analysis. They allow you to specify the failures that propagate along your system more formally instead of encoding the failure type just as part of the name. The guidewords to be used are fully customizable to the failure types used in your own projects or domain.
Flow type systems for functional data flow or component models
In the same way as the failure type systems allow a formal specification of specific propagating failures, flow types formalize the signals and information, which flow through the functional or logical architecture. Within safeTbox 2.0, it is not only possible to specify flow types and failure types separately, but to define dedicated refined failure types, which are applicable for the specific flow types. In this way, failure propagation modeling is made more efficient and unambiguous as consistency and matching between flow types and failure types can be automatically checked.
Analysis capabilities
Fault Tree Quantitative Analysis
In this version, the Fraunhofer IESE computation backend has been extended to support a larger set of failure distributions (Fixed, Rate, Dormant, and Time at Risk) for the computation of the occurrence probability of Top events in the context of Fault Tree Analysis. Moreover, metrics for importance analysis (Fussell-Vesely and Birnbaum) have been added.
Reliability Workbench/FaultTree+ integration
We have integrated the new version of Isograph Reliability Workbench (RWB) (FaultTree+ V13) as an alternative computation backend for Fault Tree Analysis. Although the Fraunhofer IESE backend already provides support for qualitative and quantitative analysis, with RWB you get an even larger set of computation capabilities (e.g., larger set of failure distributions). Since the FaultTree+ computation engine of RWB is qualified according to common safety standards like the automotive ISO 26262, the integration with safeTbox allows you to build confidence in the fault tree analysis results without having to recreate the safeTbox models in FaultTree+. In this way, you can start the FaultTree+ analysis and view the results directly in safeTbox. If you want to use the larger feature set of FaultTree+ to perform subsequent analyses not possible in safeTbox, you can easily export your safeTbox (component) fault trees into the FaultTree+ file format and continue in FaultTree+.
Infrastructure enhancements
User experience performance program
Now you can actively participate in the development of the tool by giving us feedback. With this feature, you provide us with usage statistics that will allow us to make the tool even better. The reported data includes the possibility to semi-automatically report software errors to the safeTbox team that will provide fixes in future versions. In addition, the reported data contains anonymized data about how you interact with our tool (e.g. which features are used most often). In this way, we can provide new features making tedious tasks more efficient in the future.
Compatibility with previous versions
We have built the mechanisms (model upgrader/downgrader) that will allow you to use your existing models with the newer versions of the tool. This means that models will be automatically upgraded at project opening so that you can immediately make use of new features on models from old versions.
Usability enhancements
Analysis feedback
Now you will receive more and better feedback during the analysis phases. Moreover, you can now cancel the analysis, if desired.
Properties view
This feature combines the functionality of EA properties and Tagged Values views in a more usable user interface. It provides easy access to all attributes added as part of the safeTbox modeling constructs.
