Did you know that you use patterns every day? It’s a very powerful mechanism and much more powerful when they are explicit and known. A pattern describes a proven solution for a problem. Every experienced engineer has a huge set of patterns. Think about your daily work. If you must solve a problem that you’ve solved successfully before, you will remind your solution and apply it again. If you describe your solution in a general and reusable way, you’ve made your...

I proudly present the Nordic Systems Engineering Tour - a one-day conference event at three different locations in three days. From Hamburg via Copenhagen to Stockholm. Together with Erik Herzog I had the idea to boost systems engineering in northern Germany, Denmark, and Sweden. Why these countries? The answer is easy: Erik lives in Sweden and I in the north of Germany. Denmark is located in between. Of course that's not the only reason. The purpose of the events is also to...

The previous posts Death of the Actor and Death of the Use Case reported about two serious killings in the modeling scene. Many eyewitnesses commented the report. Now it is time for a short review. First the good news: The concepts Actor and Use Case survived the massacre. I’ve seen them still alive and very active in many projects. Sadly the SysML/UML model element Actor is dead – rest in peace – and the modeling element UseCase is in intensive care. The concept Actor...

Although UML is a modeling language for software, it is sometimes also used in systems engineering projects. Since SysML is a kind of a profile you can define your own SysML stereotypes to use a UML modeling tool for SysML modeling. Please click here: http://list.ly/list/2io-popular-uml-modeling-tools  ...

After killing the Actor in The Death of the Actor my next victim is the use case. Don't use Use cases in SysML (or UML) models anymore! My statement seems to be revolutionary or stupid (or both). Just to be not misunderstood, I'm not against the concept of use cases and actors. I believe that the SysML model elements Actor and UseCase are not necessary and useful. I've already explained it for the Actor in my previous post The Death of the...

Please click here: http://list.ly/list/23A-popular-sysml-modeling-tools Unfortunately I have technical problems with the list.ly Wordpress plugin and can't show the list embedded in this blog post....

Many companies deal with the challenge to introduce MBSE. As a consultant for MBSE I often ask my customer about their objectives to apply MBSE techniques. The answers are more or less the same: the systems are getting more complex and at the same time we must decrease costs and time-to-market and increase the quality. These are good arguments to change development processes and to apply MBSE. However these arguments are not new. I would had heard the same arguments 20...

It is very well unknown and I know only a single modeling tool that explicitly supports it: the SysML activity tree. Although it is very useful and supports common systems engineering practice. What am I talking about? You may know use cases and activities to describe the use case flows. Simply spoken they describe the functions of the system from the user perspective. The following figure shows a use case and the activity of a forest fire detection system (FFDS), The...

Models do not only contain the "real" artifacts for your system, but also additional auxiliary information like notes, issues, images, and so on (metadata). It is very useful to store such information at the place where you need or create it. Switching from one tool to another is a hurdle that prevents people from looking up things or creating ones. As a result many little deficiencies occur that lead in summary to less quality, more effort and costs. My previous post...

The extended system context describes the system interfaces and the detailed connection to the system actors and to the internal parts of the actors. In the previous post How to model a simple system context with SysML I've written about system context in general and the simple edition of system context that is simply spoken just a list of external systems and human actors who interacts with the system under development. The extended system context adds information about the interfaces at the...