Evolution of Model-based Design
The system development of automobiles is a primary example of when model-based design is often used in actual development.
Units, such as the transmission, power steering, ABS, and drive control, are all controlled electrically by the software built-into the ECU making the electrical control of the engine a type of computer. These complicated ECU need to be examined to realize a system that moves as the driver desires while connecting these units.
Of coarse, all of these units can be examined using a prototype vehicle, but the rework required when a defect is discovered could be immense. Front-loading development related to examining each units independently as well as at a system level is vital to reducing the cost and risk of development.
This solution is referred to as model-based design.
Model-based design is a method to evaluate a system (plant) by expressing each unit as a model and simulating the interface between each model virtually on a computer.
Model-based design is advantageous to evaluate the entire system as the time lag of a single unit can have devastating effects to the entire system in the ECU used for communication.
Model-based design may be a new term, but the actual concept has been around and is simply an extension of current processes.
In the past, information about parts was offered as diagrams and specifications. The system engineer would create the layout design based on these diagrams and manually calculate the performance and quality. In this case, the diagram equals the model.
However, the information that used to be provided in diagrams is now offered as three-dimensional data following the standardization of 3D CAD.
The concept of providing this information as a model has not changed even though the three-dimensional data now used as the model.
Exchanging the information as a diagram may seem like a method used a generation ago now that using the three-dimensional data has become the expected format, but the idea is still the same.
The geometry has evolved from two-dimensions on paper to three-dimensional digital data vastly increasing the amount of information, which in turn increases the expectations for higher performance.
How will the machine operate if I apply voltage? The designs are now performed knowing how much performance can and cannot be achieved.
Model-based design will also become a process everyone will learn, just as the geometry has evolved.
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