Andromeda is a risk analysis software developed at EDF R&D and engineering divisions.

The software responds to an upcoming complexity challenge related to PSA model engineering: How to remain efficient and how to ensure quality of PSA models when:

the complexity of PSA models has increased

a high number of model elements (the model size) makes it difficult to retrieve model documentation

models have to be developed and "maintained" over long time periods (life cycles)

multiple model engineers are developing on same PSA models at same time

new model engineers have to "understand" complicated pre-existing PSA models in order to maintain them

The primary goal of Andromeda is to provide functionality to "understand" and "manage" PSA models. This is explained more in detail in the sequel.

First and foremost Andromeda focuses on "understanding" existing PSA models. PSA models can be composed of thousands of individual model elements. Finding information or the relevant model element is not always obvious. Also when model life cycles are long, model engineers that developed the original model may no longer be available to consult. And model documentation can be outdated or difficult to explore. Andromeda provides generic possibilities to extract pertinent information due to a model's structure and content.

Next, different model engineers may develop the same model at a time (what is referred to "concurrent model engineering"). With classical PSA software it is often difficult to "integrate" different developments (that have been made in "parallel") into one final PSA model. Functionality is needed to "merge" different developments and also to compare them to previous model versions in order to verify (cross-check) modifications or to justify those to regulator authorities. Andromeda provides functionality to compare and merge PSA models.

Further, companies may want to generate certain PSA model parts in order to regain efficiency and to avoid modeling problems. The generation can take into account "higher level modeling" languages which are able to represent models parts more readable and compact. The final PSA model can then be obtained by "assembling" a set of generated and manual model parts. Andromeda provides the architecture to develop tailored model assemblings, higher level modeling languages and corresponding generation routines.

Finally, model engineers execute often tasks that :

are very specific to a certain problem and thus difficult to be considered by classical PSA software and that

have to be applied in the same (or a similar) way for a large number of model elements (so-called "repetitive tasks").

An example of such a task would be to update all fault trees of a PSA model by removing / adding a basic event "x" if and only if the fault tree contains a gate "y". The number of such kind of examples is very large and classical PSA software can only provide solutions for some of them. Andromeda provides a "Shell and Scripting Interface" that permits to develop new solutions to new problems "on-the-fly" (without recompiling the tool or waiting for the next release that would consider a certain solution) via commands and scripts.

See Features for a closer illustration of several Andromeda features.