We are pleased to present LemonTree 4.1 with interesting new features!

Dr. Konrad Wieland

The LemonTree.Connect Workflow

Manage models over their entire life cycle

The LemonTree.Connect product group connects ALM systems with Enterprise Architect and at the moment consists of two connectors (codebeamer, Polarion).

Currently, LemonTree 3.3.1, LemonTree.Connect codebeamer 2.6.0 and LemonTree.Connect Polarion 1.2.0 are available. Both connectors belong to the LemonTree product family as they are based on the same technology. During import and export, a comparison is made and the difference is calculated so that only this is transferred during synchronisation to improve performance. The main focus of both integrations is the exchange of traceability information (references) between the two worlds of ALM and Enterprise Architect (UML/SysML).

Tools for application lifecycle management (ALM) support the entire lifecycle of software from design to maintenance. They quickly and clearly show which requirements have already been taken into account in the software. By connecting to the Enterprise Architect modelling platform, system architects and engineers can create accurate models based on the requirements. At the same time, it is ensured that these requirements are covered by the models and that the effects of changes to requirements can be easily determined. Wieland: “Modern development processes are driven by more and more data, which is often maintained in different systems. Therefore, it was clear to us that we should build a powerful link between the modelling world and requirements management. This opens up the benefits of both worlds to users, allowing them to manage growing complexity while maintaining a high level of flexibility.” LemonTree.Connect basically works as a connector even without a LemonTree licence. However, if the LemonTree functions are activated, then many additional possibilities arise that make the daily work with the models much easier.

LemonTree.Connect closes the loop between requirements and model artefacts in an MBSE environment. This enables users to easily monitor and manage complex product development processes, even in highly regulated industries.

Model parts for the supply chain

In many sectors, such as the automotive industry, the companies involved in the product development process today often see themselves as elements of networked supply chains that continue to become more and more complex. Therefore, a product like LemonTree, which is used at a very central point of model-based development, must also meet these requirements. With LemonTree.Components it is possible to detach model parts or components from a model and make them available to suppliers for further development. Once external development is complete, the component can be easily reintegrated into the model. Conversely, developers at suppliers or from other internal departments can import predefined model packages into Enterprise Architect for further development. In addition, model parts can be defined as “read-only” so that a supplier can use these parts but not modify them.

Connecting LemonTree.Components with LemonTree.Automation

In order to operate lifecycle management for parts or individual components of a model created with Enterprise Architect, the model must be split up. The resulting sub-models can then be maintained individually. LemonTree.Components makes it possible to specify parts of an Enterprise Architect model as reusable components and to separate them from the model. These components can then be edited as an independent model, versioned and reloaded into the overall model.

LemonTree components are extracted from the model via export and imported into another model via import. This restricts distributed editing to specific parts of the model. With LemonTree, differences in the edited components are quickly recognised and visualised. After adjusting the component in a so-called working model, the changes are integrated back into the original overall model.

Depending on the working method, the overall model is regularly updated and a new revision of the components is imported. This task is taken over by LemonTree Automation, integrated in a build server pipeline. In this way, models are integrated into familiar processes and changes remain visible and testable.

An example workflow for this procedure was recently presented in the white paper: “LemonTree Automation – How to work successfully with LemonTree Components in a build pipeline using version control” (see info box).

More information about LemonTree.Connect

Changelog LemonTree.Connect codebeamer 2.6.0:

Download LemonTree.Connect codebeamer:

Download LemonTree.Connect Polarion:

Further information can be found on the help pages for the two connectors:
https://help.lieberlieber.com/codebeamer.html
https://help.lieberlieber.com/polarion.html

Find the appropriate training for the optimal use of LemonTree:

AUTOSAR-UML Bridge

LieberLieber and IncQuery have a long-standing partnership in the area of model-based development with Enterprise Architect and LemonTree. This collaboration has now resulted in the AUTOSAR-UML Bridge by IncQuery, a powerful solution for bridging the gap between AUTOSAR and UML. It enables developers to streamline the development process and improve the overall efficiency of system design.

The IncQuery AUTOSAR-UML Bridge is tightly integrated with LemonTree. This integration allows automotive systems or software engineers to use LemonTree’s capabilities to easily track AUTOSAR changes by re-importing and securely merging them into the Enterprise Architect UML project. This way, UML stakeholders can stay on the same page for each project iteration without wasting time on manual reviews and data entry.

Christoph Hinrichs

Clear MBSE strategy and thorough testing of the tools

Webasto did not want to leave anything to chance when entering MBSE. Therefore, a clearly structured modelling process was defined (MBSE Meta-Model), the language to be used was defined (SysML) and the appropriate tool was selected in a very elaborate back-to-back comparison. “We were not satisfied with our previous solution and in a very open and selective tool comparison, Enterprise Architect clearly convinced us with the best cost-benefit ratio,” Hinrichs describes. The continuous responsiveness of the LieberLieber team with regard to open questions also left a very positive impression: “Since we always want to have the latest tools in use, we quickly switched to Enterprise Architect 16. LieberLieber supported us very well in this and also updated LemonTree promptly so that we could continue to use the whole tool chain.” In the end, LieberLieber’s recommendations regarding the tool chain were adopted, but Git was replaced by IBM RTC.

Dr Konrad Wieland, Managing Director of LieberLieber, comments: “We are very pleased that Webasto has chosen the path towards MBSE together with us. Christoph Hinrichs is approaching this major task in a very clearly structured way and gave us interesting insights into his pioneering work at the MBSE Summit 2022. We are united by the common goal of communicating the benefits and advantages of MBSE in a comprehensible and practice-oriented way and thus successfully convincing people. In this way, we are creating a good and robust basis for the continued economic success of the outstanding family-owned company Webasto!”

Communicating the benefits of MBSE throughout the company

For Hinrichs, it is clear that the greatest benefit of MBSE only comes when the process has been rolled out throughout the company and is working. This is confirmed by scientific studies and practical experience alike. “As usual, we first launched pilot projects to show what is possible with MBSE and what benefits arise from it. The experience gained is then processed – as in the Business Unit Batteries Department – and shared with the business units. Now we have to scale these experiences and anchor them in the business sections. For this, however, we still have to do a lot of convincing with the support of LieberLieber,” explains Hinrichs.

The most important advantages of MBSE were defined as:

• Transparency – recognition of dependencies, Defined starting point for cooperation.
• Traceability
• Visualisation – common language and the appropriate tool for each case
• Reusability and automation – Multiple use of artefacts and models; Automated consistency check of models
• Quality – Higher product maturity through semi-automated validation; Fewer errors
• Processes – Standardised processes facilitate collaboration; Certifications more quickly attainable

“The faster we integrate these points in the company, the more benefits we can derive from MBSE,” Hinrichs knows. However, it is important not to take any hasty steps, but to first check exactly what the current situation is in a department. Based on this, MBSE can be introduced in a well-controlled process without losing the necessary participation of all those involved by overtaxing them.

MBSE maturity level of a department is assessed in advance

In order to make the introduction of MBSE in other departments as smooth as possible, Hinrichs is developing an ever more detailed maturity model. Currently, there are very few publications and contributions that attempt to support the introduction of MBSE in a systematic and structured way, such as the work of Andreas Vogelsang. “There are studies on the collection of MBSE maturity levels, but no one talks about what effort it takes to reach a level or what benefits can be achieved with a level. In the practical test, for example, we found that the levels have to be as small and solution-oriented as possible so as not to trigger excessive demands, otherwise we would lose interest in MBSE or even meet with resistance. If we want to change something in the processes, methods or tools, we need a team that sticks together and pursues a common goal,” Hinrichs explains.

Key user as communicator for MBSE

As a central point of contact, a “key user” should be found in each department who is available as a multiplier and communicator for MBSE. The fundamental basis for scaling MBSE is the tool setup adapted to the needs as well as the configuration management. Hinrichs supports and disseminates MBSE within the company through internal training. This should help generate enthusiasm for the MBSE initiative at Webasto, establish initial contact and build up a network. If detailed expert knowledge is then required, or if the key user team encounters challenges in the tool, LieberLieber is available for this at any time. “Currently, three pilot projects are running in parallel, one of which is also already at a next higher level in the maturity model. So we are working intensively on establishing and scaling MBSE in the company. There is still a lot of work ahead of us and it is reassuring to know that we can always call in the experts from LieberLieber to solve difficult questions together if necessary,” explains Hinrichs.

Dani Mannes

The architecture is a model expressed with UML/SysML

In Mannes’s experience, agile development teams often focus on sprint-based delivery of user stories and the related working code. Conventional teams, on the other hand, often start development with an intensive architecture and design phase. For him, this raises the question: do architecture and design belong to the past or can architecture modelling and agile work be combined?

According to Mannes, many of ACTL’s clients in the defense industry are used to waterfall-based processes. This is often driven by contractual constraints and the perceived need for systems engineers to mitigate risk and manage development at scale through a pre-designed system architecture. However, he says, the reality is that the architecture and blueprints often change when implementation begins, making the architecture and blueprint outdated. Because of these changes, documents such as the System Subsystem Specification (SSS), System Subsystem Design Document (SSDD), Software Requirements Specification (SRS) and the Software Design Document (SDD) have to be rewritten or updated several times to reflect the actual requirements and design. But how can this effort be avoided?

The answer is quite simply, according to Mannes: by seeing architecture as a model expressed with UML/SysML. For him, architecture is a simplified description of both the static and dynamic aspects of the system. It is used for communication in the team, for discussion and as a reference when extending the system. Mannes: “If you want to talk about architecture, what does architecture look like? Well, our answer is that the architecture is a model expressed using UML/SysML. The model also serves as the knowledge base from which the required documents can be generated. And with Lemon Tree the model can be version managed along with the contractually required documents.”

But the model is only a means of communication and not a goal or end in itself. Therefore, he says, the model does not have to describe the complete solution, but only the necessary aspects for:

• Discussion of the current large-scale structure and mechanisms
• Assessing the impact of current decisions
• Ensuring that the different parts of the system are clearly separated and their interfaces well defined, and that the parts together contribute to the current scope of system functionality

From methods and processes to MBSE

In its two training courses (UML and MBSE/SysML), ACTL primarily teaches methods and processes. Only if the use of tools is explicitly desired, the training is extended accordingly. “We want to slowly introduce interested parties to the topic of modelling and show them where modelling will bring them the most benefits. In this way, we create the basic prerequisites that can then be implemented with tools such as Enterprise Architect and LemonTree.”

In MBSE, ACTL currently has two major projects, one of which relies on Enterprise Architect and where LemonTree would also fit in well. “The international INCOSE association is very active in Israel on MBSE. But there is still not enough awareness among companies,” says Mannes, who still sees a lot of work ahead of him, which is now to be managed even better together with LieberLieber.

In 2021, the German agricultural engineering family group CLAAS generated sales of 4.8 billion euros with around 11,900 employees. Within the group, CLAAS E-Systems is responsible for the development of electrical and electronic systems for agricultural machinery. Enterprise Architect has been used there for many years as the standard editor for modelling SysML and UML models. Now, LemonTree has also been added to the engineering tool chain. For the realisation of future digitisation projects, powerful tools are thus available to apply the necessary development processes and methods in a targeted and efficient manner.

Dipl.-Ing. (FH) Theodor Jäger

Making Systems Engineering easier

When Jäger joined CLAAS E-Systems about two and a half years ago, he brought with him more than 20 years of experience in the development of mechatronic systems. At an automotive supplier in Sauerland, he developed mechatronic systems in international projects in various roles and positions. As a coach for processes, methods and tools, he most recently supported project teams in modelling their systems in SysML. Jäger is particularly concerned with keeping systems engineering simple. In doing so, he heeds the advice of physicist and Nobel Prize winner Richard Feynman: “If you cannot explain something in simple terms, you don’t understand it.” Jäger translates this with regard to MBSE and explains: “People also need MBSE to be presented and communicated in a way that fits into today’s working environment: Simple, with catchy explanations, concise pictures, in small servings. Hardly anyone reads a ten-page text nowadays. Even if the benefit of an activity is not immediately clear, motivation decreases. Only if it is meaningful and simple, and in the best case also fun, will new methods and processes be accepted in the organisation and also be brought into everyday use beyond locational boundaries.”

Close cooperation with LieberLieber on modelling

The cooperation with LieberLieber is very good, for example because of the fast support offered, a common language and time zone. Last but not least, mutual appreciation and trust. For Jäger, the support behind the tools via support and consulting is essential: “There are always questions that can be better clarified together. That saves time and money, and there is more time for engineering to provide top-class services. LieberLieber also realises individual adaptations quickly. Furthermore, the licence costs are moderate and the users get along very well with the tools.”

Dr Konrad Wieland, CEO of LieberLieber: “We already knew Theodor Jäger from projects in the automotive industry and are very pleased to now be able to support major digitisation projects at CLAAS together with him. Agricultural engineering is also facing major upheavals similar to those in the automotive industry. For example, new and stricter legal norms and standards, especially in the area of safety and security, are an issue in agricultural engineering. But they can be mastered very well with MBSE and our tools. In any case, we will continue to expand our service and support in order to be able to serve CLAAS in the best possible way.

Implementing legal regulations safely

The operator’s cab of an agricultural machine is where all the information comes together and is made available to the operator. All machine activities are initiated from the cab and many are safety-related. The development process for agricultural machinery must therefore comply with ISO 25119, the standard for functional safety in agricultural machinery. However, functional safety only exists if the software does exactly what it was built for. And that is guaranteed by ISO 21434, the standard of cybersecurity for road vehicles. “The modelling of the system architectures with Enterprise Architect and the use of LemonTree for model comparison and model versioning systematically support us in this and thus create an important working basis for meeting these standards,” concludes Jäger.