Model-Based Systems Engineering

By: PeopleTec Model-Based Systems Engineer Jason Mabry

What is “Systems Engineering”?

Systems engineering involves an integrated approach that crosses disciplines to allow successful realization, use, and retirement of systems. It uses system principles and concepts in addition to scientific, technological, and management methods to form an appropriately structured development process from concept to production, operation, evolution, and eventual disposal.

Systems Engineering facilitates and guides the integration of relevant disciplines and specialty groups into a cohesive effort. It considers both the business and the technical needs of customers with the goal of providing a quality solution that meets the needs of users and other stakeholders. Systems engineering is appropriate for real-world operation and avoids or minimizes adverse unintended consequences. (International Council on Systems Engineering (INCOSE))

In 1967, Hendrik Bode told the U.S. House of Representatives: “…the systems engineer resembles an architect, who must generally have adequate substantive knowledge of building materials, construction methods, and so on, to ply his [or her] trade. Like architecture, systems engineering is in some ways an art as well as a branch of engineering. Thus, aesthetic criteria are appropriate for it also. For example, such essentially aesthetic ideas as balance, proportion, proper relation of means to ends, and economy of means are all relevant in a systems-engineering discussion. Many of these ideas develop best through experience. They are among the reasons why an exact definition of systems engineering is so elusive.”

What is Model-Based Systems Engineering (MBSE) and what are its origins?

In September 2007, INCOSE introduced its “MBSE 2020 Vision” that stated: “MBSE is expected to replace the document-centric approach that has been practiced by systems engineers in the past and to influence the future practice of systems engineering by being fully integrated into the definition of systems engineering processes.”

MBSE has been a buzzword for more than 18 years. According to the INCOSE, “MBSE is 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.” NASA adds, “system relationship models are useful for showing relationships among system functions, requirements, developers, and users. These models support 3 aspects of systems engineering:

  1. System Functional Flows (i.e., System Architecture)
  2. System Requirements Traceability
  3. System and Organizational Process Flows

MBSE is a technical approach to systems engineering that focuses on creating and exploiting domain models to exchange information rather than using documents to exchange information. MBSE approaches are commonly applied to a wide range of industries with complex systems, such as aerospace, defense, rail, automotive, and manufacturing. (INCOSE)

At its heart, MBSE is an application of systems engineering. It is a tool in a systems engineer’s arsenal that allows them to communicate ideas and designs into consumable data for all disciplines across a program to work from. MBSE turns common vision and design decisions into a picture, and a picture is worth a thousand words.

What MBSE is NOT

MBSE is not a modeling language, like SysML (System Markup Language). It is not an easy button that will magically turn drawings on paper napkins into analytical, logical, behavioral, and architectural models.

MBSE is also often confused with MOSA (a “modular open system approach”). However, they are not the same. For more on MOSA, read our blog post here.

Problems with implementing MBSE

We currently face many challenges with the implementation of MBSE. For example, industry has found it difficult to fully transition from the current system’s engineering and acquisition approach to the more beneficial and cost-effective MBSE approach. While many teams across the Services are requesting original equipment manufacturers to implement MBSE, in many cases Government contracting has not caught up. Oftentimes requirements are unclear, and deliverables do not align with the MBSE approach (for example, requesting documents instead of models, and then not knowing how to review/validate the delivered models).

In addition to the contracting issues, our workforce does not support a quick transition to MBSE since current tools and training is not easily available or standardized. Ultimately finding systems engineers who can operate within an MBSE environment, provide subject matter expertise about the system, and bring experience in acquisition is very rare, particularly those willing to work in the Defense sector, which typically results in tradeoffs between system experience and tool experience.

What PeopleTec is doing to grow the capability

PeopleTec has established and champions an MBSE Community of Practice (CoP), which was created to help close gaps of implementation by growing our own qualified MBSE practitioners to assist the Government with filling their demand. It also provides a support network for systems engineers involved.

PeopleTec’s MBSE CoP is building an understanding of and a culture around the many facets of MBSE, and we are exploring how to create the best solutions for Government problems. Our CoP captures the “Best Practices” and shares knowledge to drive process commonality and synergies across the company.

Finally, PeopleTec’s MBSE CoP is developing a “curriculum” that organizes training for all current and future employees. This curriculum allows our managers and leadership to understand the proficiencies required of a systems engineer. This curriculum is made up of the following: