Definition of MBSE

There is a lot of information about MBSE available: books, blogs, podcasts, videos, and so on. But how it MBSE defined?

MBSE stands for Model-Based Systems Engineering. A good source for systems engineering definitions is INCOSE. They define MBSE as follows:

The formalized application of modeling to support system requirements, design, analysis, verification and validation activities beginning in the conceptual design phase and continuing throughout development and later life cycle phases.

SEBoK Glossary

INCOSE is not an official standardization body like ISO but represents the systems engineering community. Their definitions have a comparable status as a standard.

I could not find any definition of MBSE from an official standardization body. Do you know one?

Coming back to the MBSE definition from INCOSE: I am not happy with it. In my view, it is too weak and limited.

It is not wrong that models support the systems engineering activities. However, it does hit the nail on the head. I would prefer that the definition covers the essential purpose of the models more precisely than just saying that they support something.

Models have many advantages: they provide structure, illustrative graphical views, enable reuse, and so forth. However, you can achieve these advantages also with a document-based approach. Although I guess it is more efficient to use models.

The unique advantage of models is that the engineering data is transformed into engineering information by adding semantics via the modeling languages and that the models make the engineering information accessible to machines.

If the engineering information can be understood by machines, they can support engineering activities, but also actively drive activities when we think of artificial intelligence, for example.

The INCOSE definition limits the support of models to only a few systems engineering activities. In my view, models can be helpful in all systems engineering processes defined by ISO 15288.

So, I would define MBSE as follows:

Model-Based Systems Engineering (MBSE) is systems engineering with the formal application of models to make engineering information accessible to machines to support the system engineers.

Tim Weilkiens

An important part of the definition is the term “model”. I agree with the definitions of “model” given by the SEBoK (see here), but all lack an important feature of an MBSE model:

An MBSE Model is based on a modeling language that covers the systems engineering domain concepts.

Only if the modeling language includes the semantics of systems engineering concepts can the models be understood by machines.

The term MBSE can be traced back to Wayne Wymore. Its definition is very mathematical and difficult to understand. This does not make it wrong, of course. But I think it needs different definitions (views) for different target groups, but not contradictory. An interesting article about Wymore and the scientific foundation of MBSE can be found here.

Do you know other definitions of MBSE? I would like to collect published definitions and make transparent what they have in common and where they may also contradict each other.