Why use a “model-based” approach? What advantage is there to be gained from this approach?
Let’s begin by noting that all systems engineering is model-based. It isn’t possible to think of, discuss, or design systems without using a model. The concept of the system, its functions and parts must be formed first in the mind of the engineer and then realized. The conceptual image in the mind of the engineer guides the physical realization.
The difference that sets model-based engineering apart from other methods is not that a model is present; it is that a model is created in an accessible and intentional format so that it can be used by anyone involved in the design. Instead of being hidden away in the mind of the designer, the model is exposed for all to see and work with.
The exposed model presents a number of advantages for the design team.
The model is clear and unambiguously displayed. There is little or no room for dispute (depending upon the quality of the meta-model for capturing the system nuances accurately) as to the nature and scope of the system being designed.
The model incorporates design work in all four domains. Work in each domain is linked to the others, so that impacts and dependencies are tracked and included in the design. With a single model, the design intricacies are not lost in translation between domains.
The model can be modified to test alternative designs. This refers to the ability to test and think through the alternatives without the necessity for physically-realized prototypes. This saves costs and time. It also encourages the exploration of more and varied design alternatives, thereby raising the quality of the final design.
Design complexity is captured, preserved, and accounted for more easily and accurately. The model instantiates and preserves complex relationships in an accessible and visible way. Changes adding detail and/or dynamic complexity can be seen and remembered in the model.
The model makes communicating the system design more accurate and efficient. The impact of proposed changes can be readily seen and discussed and everyone involved in the design can align to the status in real time by looking at the model.
Collaboration is promoted by the clarity and improved communication, so that ideas can be shared and captured in the model. With model-based systems engineering, there is an increased level of synergy in the design process.
All of these advantages are gained by exposing the model in an accessible form for team interaction. Instead of operating from multiple models hidden in the minds of the design team members, the team can collaborate in the development of a single system solution expressed in a unified model. The ultimate solution is richer and obtained at a lower cost in terms of time and money.