How model based design could improve development
Those who encountered control, communication or other dynamic systems during school time, they dealt most of the time with block diagrams, state machines, electrical circuits or other visual methods to address the design of complex problems. Model-based design methodology will let you easily utilize these experiences when you design embedded software. Besides the simplicity of the design, it has many other assets. However, it is not commonly used in all industries, and in this article, we briefly show why this methodology should be adopted in more industries.
No doubt that model-based design is one of the methods that brings the control, communications, signal processing and dynamic systems to a great level. Designing for example model predictive or even nonlinear control systems are more feasible and less error-prone using this approach.
Model-based design methodology, especially in the starting stages, is used in many elds such as automotive, aircraft, robotics and others. In the other industries for example the automation industry, they tend to neglect this phase and hard-code the software program in the PLC and connect it to a simulation platform to evaluate system performance. In this article, we are briefly discussing the improvement and the value of starting the design process with the model-based design approach and how that can impact the automation industry.
In the model-based design scheme, knowing the mathematical representation, it is easier for a developer to design the model of the plant. Based on that, one can synthesize a suitable controller for that plant using graphical-interface-user blocks that represent simple arithmetic, logic and other simple operations or even more complicated operations such as PID and model predictive control blocks that handle more complicated operations, in the absence of the actual hardware. This will save a huge amount of time for a developer if he would like to code the whole system. As a result it is much easier to debug and improve the control algorithms quality. What is more interesting, even without knowing the mathematical representation of the plant, you can model the plant by depicting electrical or mechanical circuits and connected to scopes or displays blocks to observe their outputs. Verification of the design could be handled through Model-In-The-Loop(MIL) and Hardware-In-The-Loop(HIL) simulations. In the MIL you can test and validate the simulated controller and plant in the early phases without physical components. Once the model is tested in MIL, you can output HDL code, C code, IEC61131-1 Structured Text (using PLC coder) and reports. In the HIL method, HIL simulators will be used to act as a real plant and will communicate with controllers through sensors and actuators. In which testing is more realistic and then you are ready to go to test the prototype.
There are many advantages of using the model-based design approach. For example, most of the verication and validation could be done earlier before the hardware exists, as well as, adding new features will take lesser time and the development schedule will be shortened. Moreover, some model-based design platforms provide code generation feature that is optimizing the code in which more memory space and high execution speed are provided. All in all, one can see the benefits of considering a model-based design approach in the development process and how that will increase the quality of the testing of the system and decrease the errors that could be expensive in the real application.