Safety Analysis depends on what you contain in the Architecture. So…


Assuming that FMEA and FTA can be generated from Architecture(Sys/EE/SW), quality and depth of safety analysis depends on what you decide to cover in the architecture.

If your architecture is too detailed contents, then it would be labor intensive work. In the SW safety analysis, detailed SW safety analysis is not recommended. For example, ISO 26262 does not require that variable level fault mode has to be considered. If you refer to some papers, you can see such approaches. They always tell us that such task is time consuming work.

In the sense, granularity of architecture is so important. Because FMEA and FTA are different shapes of the diagram for chosen architecture view point, it is so important what kinds of view point has to be necessary.

If you refer to these safety analysis results to specify safety requirements, it will be clear why this requirement is safety related requirements.

While system in the automotive and aircraft vehicle focus on engineering methods to control vehicle, but socio-technical systems such as CNS/ATM system additionally requires related operation process. In this case, FTA and FMEA can enlarge to the operation process scope.

If you understand the principle, it can be applied to different domains.

Thus, important thing is how to determine what contents have to be contained, and how deep it has to be specified. It sounds like boring, but if you do not consider very carefully, you will have poor results even though you spend too much time.

In general, this consideration is functional safety manager’s role. On the contrary, functional safety engineer who knows deep knowledge about product would be hard these determination. Such person is apt to cover contents that does not have to be covered in the safety analysis.

So such policy is necessary. and it has to be determined by functional safety manager and agreed by related functional safety engineers. If there is no policy, you will face overlapped specification among system, SW and EE level.

 

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Resource reduction for functional safety projects


How can we reduce resource in the functional safety project?

It is easy to say that we develop perfectly and reuse without modification for the next project. But how?

  1. build platform to support functional safety project.

  2. build library asset for functional safety project.

These projects are not customer based project. But I believe they are most important.

in these projects, every work products have to be produced and they should be linked to individual customer project. To achieve them, additional project team has to be organized and it consists of best experts.

Is FSM a Manager or an Engineer?


As a functional safety manager, someone focus on safety engineering while the other person focus on management. Nowadays I realize that safety engineering is different from safety management and they require different technique or skills.

Safety engineering is do something for his own knowledge, while safety managing is not engineering. He makes plan and determine schedule.

In some ways, they are quite different. It would be great if a person covers both functional safety engineering and functional safety management. But I’m not such a person. I’m more close to functional safety manager than functional safety engineer.

To be a manager, managing skills are required. I think project manager can take a functional safety manager role if he study ISO 26262, but it would not be easy to be a functional safety engineer.

As a functional safety manager, I use management tools(confluence, JIRA, Polarion etc) fluently to manage. I think it is essential. But for safety engineers, it is not mandatory.

I’ve never distinguished between two roles before. Now I realize uncovered fact.

ISO26262, DO-178C, DO-278A