1. 1 Decomposition: Architecture & Trade Studies Mark E. Sampson UPDATED 9/20/04 EMIS 8390 Systems Engineering Tool—applying tools to engineering systems

2. 2 Architectural Frameworks… …a means of representing, capturing, communicating system architectures from a variety of perspectives… 100’s of frameworks out there… Aimed at different problem domains Business/IS systems… Zachman, SEMS, EPIC,… Tools help capture & support these frameworks… CaseWise, Synthesis,… Usually can’t buy them without consulting Business consultants each have their own extensions/tools [zifa.com]

3. 3 Architectural Frameworks…continued IDEF0-9…based on SADT IDEF0—functional modeling… IDEF1—information modeling… IDEF1x—activity modeling… IDEF2—system dynamics IDEF3—process & states IDEF4—object modeling … IDEF9—user interface … IDEF14—network modeling Tools help capture & support these frameworks… KBSI, Popkin SA, ProSim,… [idef.com]

4. 4 Architectural Frameworks…continued DoDAF…next generation C4ISR Operational views OV1-operational concepts … OV5-activities … OV9-logical Data System views SV1-interfaces … SV12-events Tools help capture & support these frameworks… Popkin SA, Statemate, P-Tech… Most used is Powerpoint, Excel,…

5. 5 Architecture: Synthesis… Translates functions into physical architecture by grouping functions into logical/physical elements Elements include: hardware, software, material, data, facilities, people, services, and/or processes Alternatives are evaluated against the requirements to identify best approach Continue to develop architecture until you can verify that requirements have been met …produces WBS, spec’s, & CI’s [SE Handbook 10] [DOE 2003] Battery Processor Motor Drive

6. 6 Architecture: Synthesis… You “just” have to choose an architecture that: 1.Satisfies the requirements 2.Implements the functions 3.Within budget, time, knowledge, resources,… 4.Built with available technology & availability risk 5.Is extensible to accommodate growth & new technologies 6.Allows you to go the next level of detail 7.Is robust enough to minimize back-tracking …you may be starting from scratch or from existing art …in a changing environment [SE Handbook 10]

7. 7 Architecture: Synthesis… 1.Develop alternatives use the tools previously described—brainstorming, morphing, surveys, literature search, Pugh, TRIZ,… 2.Develop architectures from those alternatives use diagrams/models of appropriate types (at appropriate level) 3.Choose & dive to the next level apply criteria, decision trees, weighting, utility curves… Repeat until components are realizable, verifiable… [SE Handbook 10] Problem Definition Functional Analysis Systems Synthesis Systems Analysis Decomposition Verification Validation Develop Alternatives Develop Architecture Choose Alternative Develop Architecture Choose Alternative Develop Alternatives

8. 8 Modeling Methodology: Schematic Block Diagrams …capture & communicate potential product architecture, what makes it up, & their interactions Shows internal & external interfaces without pushing a particular design Encourages looking “outside the box” In our dental hygiene case, shows the preliminary product partitioning [Armstrong 1993] Partitioning

9. 9 Modeling Methodology: Behavior Diagrams …combine data flow and functional flow More thorough analysis of actions & what is being acted on in the same diagram. Support function to system allocations …tools like CORE, Cradle-SEE,…use these types of diagrams [Armstrong 1993]

10. 10 Modeling Methodology: State Diagrams …analysis of system states or modes Identify lock conflicts—on, standby,… Identify transition problems during design Presentation/Demo by I-logix In our dental hygiene case, shows the system needs to be made ready before it can be used [Armstrong 1993]

11. 11 Modeling Methodology: Object Oriented Analysis …identify what the system will have to deal with as objects Similar to mission profiles, schematic block diagrams,… UML/SysML… Presentation by Sandy Friedenthal (LMCO/SySML Partners) In our dental hygiene case, shows objects of our dental monitoring system [Armstrong 1993]

12. 12 Modeling Methodology: Data Flow …like functional flow, except emphasis on how information flows among system elements. Helps identify data input/output conflicts Data dictionaries In our dental hygiene case, shows a decomposition of monitoring brushing after meals [Armstrong 1993]

13. 13 Modeling Methodology: others… Entity-Relationship Diagrams Math models (Excel, Matlab,…) Statistical Models—DFSS,…(SAS, MiniTab,…) Performance models—Queuing, Monte Carlo, etc. (Crystal Ball, SES Workbench,…) Environmental Models— Physical Models—Hydraulics, Electrical,…(Easy5, CAERose, Matlab:Simulink…) [Armstrong 1993]