SysML Parametric Solvers
Collaborative modeling for systems engineering requires a means to integrate, control and visualize the performance of systems on a continuing basis. InterCAX is developing software to manage the link between SysML authoring tools and a variety of mathematical solvers, like Mathematica®, Matlab/SimuLink®, even Microsoft Excel®. Based on Georgia Tech proprietary technology, these new tools will add “next-gen spreadsheet” capabilities to large engineering projects in the defense, aerospace, and automotive industries. The parameters embedded in each object diagram can be linked by multi-directional equations, constraints, or legacy models, allowing real-time verification of performance, cost, and other factors against systems requirements.
This same technology can be applied to financial systems, web-based business process analysis, and defense programs.
ParaMagic™ - SysML Parametrics for MagicDraw
The ParaMagic(TM) plugin makes MagicDraw SysML models come alive! Using the quantitative information and constraint relationships displayed in SysML parametric diagrams, plus legacy models in tools like MATLAB® and Simulink®, SysML model-builders can run simulations from the earliest stages of system design. Links between SysML and Excel® make it easy to import and export data, create reports and generate graphs and charts. In traditional domains of system engineering like aerospace and transportation, users can explore system performance, check requirements, estimate cost and allocate resources. Developers leveraging MagicDraw's UPDM and business modeling capabilities can add parametric simulation using SysML submodels for defense planning, business process analysis and computational finance.
ParaMagic™ 16.5 continues the expansion of the power of SysML parametric simulation and integration with Microsoft Excel®, MATLAB®/Simulink® (The MathWorks, Inc.) and Mathematica® (Wolfram Research, Inc.). Improved features include
• Pure MATLAB solving – Users can handle all parametric calculations with MATLAB functions or scripts, eliminating the requirement for a Mathematica license.
• Aggregates – ParaMagic calculations can handle properties with list or array values (primitive aggregates) or multiple blocks with the same property (complex aggregates).
• Instance libraries – Greater flexibility in model organization means standard component libraries can now be part of your model-building process.
Building parametric models for simulation and requirements checking is easier than ever, now that legacy models and data, created and validated with many man-years invested, can be exploited within a modern systems engineering framework.
Constraint Relationships
Mathematical relationships handled by Mathematica include basis arithmetic and exponentiation, trigonometric, exponential, and logarithmic expressions, and MINIMUM, MAXIMUM, SUM and AVERAGE functions. Consult with InterCAX about implementation of other Mathematica capabilities. Because many equations can be solved non-causally, i.e. in any direction, ParaMagic-based models can be explored fully, with easy exchange of inputs and outputs. Mathematica can be installed on the local computer, or ParaMagic can support server-based licenses or web services.
ParaMagic™ 16.5 continues the expansion of the power of SysML parametric simulation and integration with Microsoft Excel®, MATLAB®/Simulink® (The MathWorks, Inc.) and Mathematica® (Wolfram Research, Inc.). Improved features include • Pure MATLAB solving – Users can handle all parametric calculations with MATLAB functions or scripts, eliminating the requirement for a Mathematica license. • Aggregates – ParaMagic calculations can handle properties with list or array values (primitive aggregates) or multiple blocks with the same property (complex aggregates). • Instance libraries – Greater flexibility in model organization means standard component libraries can now be part of your model-building process. Building parametric models for simulation and requirements checking is easier than ever, now that legacy models and data, created and validated with many man-years invested, can be exploited within a modern systems engineering framework.
ParaMagic and MATLAB
The ParaMagic-MATLAB connection wraps MATLAB script and function M-files as constraint blocks for use in ParaMagic's parametric solving process. This includes wrapping and executing Simulink models that are invoked using script M-files. Now ParaMagic can push values from the SysML model into an existing Simulink model at the correct stage in the parametric solving process, execute the Simulink model, and pull results back into the MagicDraw model.
ParaMagic and Excel
The ParaMagic-Excel connection enables users to read and write SysML instance slot values from MS Excel spreadsheets. Data from multiple workbooks and worksheets can be written in to a single SysML model before parametric calculations are executed and the parametric results can be written back to the spreadsheets. Engineers and analysts used to working on individual spreadsheets now have a collaborative tool to synchronize their efforts using the best model-based systems engineering practices.
ParaMagic and Mathematica
The ParaMagic-Mathematica connection, previously confined to basic mathematical expressions, has been expanded to open the full power of Mathematica functions. Users can create and wrap custom Mathematica functions (m-files) as constraints blocks in SysML parametric diagrams. A number of standard graphing and statistical functions are provided with ParaMagic, making line plots, bar charts and other graphical outputs as easy as dropping a constraint block into your SysML model.
System Requirements
ParaMagic 16.5 requires MagicDraw 16.5 (or later) with the SysML 16.5 SP3 plug-in (or later). It requires either Mathematica (versions 6.0 or 7.0) or MATLAB (version 2008a or later) or both.
ParaMagic FAQ
What is Parametrics?
Parametrics functionality allows SysML model-builders to include mathematical formulas as part of the model. Parametrics is part of the OMG SysML 1.0 specification.
What are Parametrics used for??
Parametrics insures data consistency within the SysML model and provides the potential for simulating model performance and comparing against system requirements. Possible usage areas:
• Engineering projects: calculate cost, weight or power budgets, vehicle speed, component strength, and others.
• Computer systems, calculate message traffic levels, database capacity needs, system availability, and others.
• Business systems, calculate manpower needs or time to delivery.
Anything from “ballpark” estimates and “sanity” checks to detailed optimization, trade studies and sensitivity analysis can be organized throughout the development process.
What is ParaMagic?
ParaMagic is a plugin for MagicDraw that extracts the parametric relationships in a SysML model, exports them to a mathematical solver program, and uploads the calculation results back into the SysML model.
It handles simulation execution, solver management, and some display functions.
How does ParaMagic work
ParaMagic creates a constraint network from the parametric model using constraint graph and “Composable Object” algorithms developed at the Georgia Institute of Technology. “Acausal” networks often make it possible to solve the model in multiple directions, swapping inputs and outputs in the different model instances or at runtime. For example, calculate the weight of a system from its individual components, or calculate the weight allowance for a specific component from the overall system weight budget.
What mathematical solvers does ParaMagic link to?
ParaMagic uses Mathematica from Wolfram Research or MATLAB from The MathWorks or a combination of the two. Solving standard mathematical equations embedded as constraints in SysML parametric diagrams requires Mathematica. Using MATLAB, constraints are written as external calls on MATLAB functions or scripts. Existing simulation models, functions and templates in MATLAB, Simulink or Mathematica can be incorporated directly into SysML models.
How does the ParaMagic-Excel link work?
ParaMagic allows data to be transferred between a SysML model instance and one or more Excel spreadsheets by creating a mapping between instance values and worksheet cells. The user can import initial data from spreadsheets into a model instance and, after running the simulation, export results to Excel for reports, graphing and further processing. Excel is not used by ParaMagic as a mathematical solver, however, so Mathematica and/or MATLAB is still required.
Can I use ParaMagic with UML, UPDM (DoDAF/MoDAF), or business process modeling languages?
The official specifications for these other profiles do not explicitly include Parametrics, but, in MagicDraw, SysML features can be linked to these kinds of models and ParaMagic simulations can be incorporated easily.
How does ParaMagic do requirements checking?
Quantitative requirements can be formulated as constraint statements, e.g. If(actual_weight < required_weight, Then Result = True, Else Result = False) and incorporated in parametric diagrams. Every time the parametric simulation is executed, the constraint statement provides a clear answer for whether the requirement is being met. Integrating a requirements management tool like Cameo Req+ with MagicDraw and ParaMagic provides a powerful approach to creating, tracing and verifying requirements.
How does ParaMagic differ from SysML simulations approaches?
Multiple approaches have been proposed, including code generation from state machine and activity diagrams and generation of Simulink models from SysML. Each approach has its applications, but ParaMagic provides a simple, flexible process with links to multiple solvers and data sources. Rather than being the best tool for creating a complex simulation of a small piece of a SysML model, it helps ties together system capabilities at the global level?
How can I learn more about ParaMagic?
Download evaluation copies of MagicDraw, the SysML, and ParaMagic plugins. Go through the demonstration models with help of ParaMagic tutorials. Free access to Mathematica as a web service from No Magic Inc. is available over the Internet during the evaluation period.
Examples of SysML model and ParaMagic results
In a simple example, a satellite with four subsystems needs to meet weight and power budget requirements. Constraint blocks, which may be re-used from previous projects, are added to the model and parametric diagrams provide the wiring between the component attributes, like propulsion system weight and the analysis equations, like WeightBalance. The ParaMagic browser summarizes the model parameters, assigns them as givens or unknowns, and prepares the system of equations for export to the mathematical solver. Results appear in the browser and can be uploaded into the SysML model.
The latest version of ParaMagic is now available for download on the No Magic website for new and existing MagicDraw customers. Watch this space for further announcements about this exciting new product or contact us directly at Info@InterCAX.com.
