Automotive functional safety ISO26262

ASIL Decomposition – What is it anyway! Let us start with the ISO 26262 definition for ASIL Decomposition: “ Apportioning of redundant safety requirements to elements, with sufficient independence, conducing to the same safety goal, with the objective of reducing the ASIL of the redundant safety requirements that are allocated to the corresponding elements .” If you feel completely lost or confused as though you read a statement in a language that you have never heard of, then you are not alone! ASIL decomposition is considered as one of the advanced topics in the safety domain and many feel intimidated to venture into this topic. The idea behind this blog is to demystify the decomposition concept and to present you with some pointers on how to use decomposition. If we have to breakdown the definition into ‘plain’ English, it would look something like this: ASIL decomposition is a method by which the requirements could be broken down into redundant requirements that are then allo...

Software Safety Analysis (SSA) is a kind-of-a verification activity that is performed on the Software to prove that it achieves all the Safety goals and provides the required Independence and freedom from interference.  Quite often we have seen that it is not clear for Software teams on how to do this analysis and which parts of the Software should they set their focus on. Also, in many cases, the activity is started towards the fag end of the project nearly when the safety software development has been completed, treating it more as a paper work to be completed.                             In this article, we present an 8-step method for performing a meaningful analysis. Before applying the method, here are some aspects to keep in mind: Basis and stage of the analysis SSA must be performed during the Architecture stage, based on the static and dynamic aspects of the Architecture. This provides the opportu...