ATICA’s Fault Tree Analysis editor is directly implemented into Capella. Compared to most FTA tools, our solution allows direct traceability from system design description to the failure events represented in the diagram.

Currently supported features

ATICA’s FTA editor currently supports the main features typically needed by systems safety engineers:

• Basic events, described by a constant failure rate (exponential degradation law).
• The events can be directly created from the editor, or referenced from the failure artifacts already present in the model.
• Gates with AND and OR behaviour.
• Transfer gates, to group part of the diagram and move it to another view; or to reference an already existing diagram.

The editor offers the typical diagram view; and also an alternative view consisting of a table, useful for the visualization of all the properties of FTA events.

Results are presented through a cut set table. Cutsets represent the minimum combination of failures that lead to the top event.
The table allows to quickly evaluate the presence of single points of failure in the design, the identification of the most relevant failure modes and the possibility to introduce mitigations with redundancies or other safety barriers.

Next steps!

We are currently working in extending the currently supported functionalities, bring-in advanced features such as more options for modeling failure probabilities (Weibull distributions), voting gates for describing complex redundancy schemes; and options to consider dormant failures for the cutsets and probability calculations.

Stay tuned for more news!