Transcript Title

Requirements Formulation: Document
Management vs. Model Based System
Engineering
Clifford Levine
July 17, 2015
Document Management
Past
Future
•
Specifications
•
Interface requirements
•
System design
•
Analysis & Trade-off
•
Test plans
Moving from document-centric to model-centric
Document Based Engineering
Requirements
Management
Requirements
Database
Word Processors
Spreadsheets
Behavioral
Analysis
Behavior
Database
Drawing Packages
Spreadsheets
Simulation Packages
Architecture
Synthesis
Verification
Physical
Architecture
Database
Drawing Packages
Spreadsheets
Verification
Database
Testing Packages
Spreadsheets
Stovepiped efforts utilizing independent representations hides context,
requires extraordinary data management, and complicates the SE effort
Model Based Systems Engineering
Source Requirements Domain
Behavior Domain
Originating requirements
trace to behavior
Data
verified by
Behavior is allocated to
physical components
V&V Domain
Data
Architecture Domain
MODEL
verified by
verified by
Originating requirements trace to physical components
Vitech Corporation
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Data
MBSE Activities Timeline – Top Down
0. Define Need &
System Concept
1. Capture & Analyze Orig.
Requirements
Can be restructured for middle out and reverse
engineering projects.
2. Define System Boundary
3. Capture Originating
Architecture Constraints
4. Derive System
Threads
5. Derive Integrated System Behavior
6. Derive Component Hierarchy
SCHEDULE
7. Allocate Behavior to
Components
8. Define Internal Interfaces
9. Select Design
10. Perform Effectiveness & Feasibility Analyses
11. Define Resources, Error Detection, & Recovery Behavior
12. Develop Validation Requirements/Validation Plans
13. Generate Documentation and Specifications
Requirements (Sources)
Potential Source
Documents
Vitech Corporation
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Capturing Operational Concepts
 Shared vision of
stakeholders
 Mission requirement(s)
 Collection of scenarios
involving external systems
 Shared vision of
stakeholders
 Mission requirement(s)
 Collection of scenarios
involving external systems
Vitech Corporation
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Requirements: Traceability
Sources
Model
Tool
Vitech Corporation
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Layered Approach
Dgn
V&V
BEH
Source
Documents
REQ
ARCH
LEVEL 1
Dgn
V&V
BEH
Docs
Docs
REQ
ARCH
Docs
LEVEL 2
Dgn
V&V
BEH
Docs
REQ
LEVEL n
ARCH
Docs
Must complete a layer before moving to the next layer (completeness)
Vitech Corporation
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Cannot iterate back more than one layer (convergence)
Level Of Detail
View Generators Using a Common
Repository Guarantee Consistent Views
• A graphical view is
defined by features
and a format
• The features are in
the repository
act Thread 1a - Product In Inventory
t1.Make
Information
Request
t1.
Informati...
Project:
Image Management_L2
t1.Accept &
Format Request
t1.
Formatte...
Organization:
t1.Get Product
From Inventory
t1.Provide
Product To
Customer
<<optional>>
<<optional>>
t1.
Inventory...
t1.Accept
Products
t1.
Collection...
Date:
August 22, 2011
View generator
contains format
rules for each
selected view
type
• The format for each
view type is defined
in the view
generator
hier Phy sical C ontext
C
Physical C ontext
C omponent
C .1
C .3
SYS.1
C ustomers
C .2
C ollectors
C ustomer
C ertification A u...
Image
Management Sy ...
C omponent
C omponent
C omponent
C omponent
SYS.1.1
SYS.1.2
C ommand Center
Subsy stem
C omponent
Project:
Image Management_L2
System Design Repository:
Features of Elements &
Control/Connection Constructs
10
Vitech Corporation
O rganization:
Date:
Workstation
Subsy stem
C omponent
A ugust 22, 2011
Automated Documentation Generation
System Design Repository
 Provided from the engineering database
(from the start)
• Uses scripts to generate document files in
RTF, HTML, & ASCII format; you publish in
your word processor (e.g., Microsoft Word)
• Captures any internal graphic in WMF, JPEG,
PNG, & SVG format
• Prints to any device if driver available, (e.g.,
laser, Postscript, plotter)
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Vitech Corporation
MBSE: Restoring Analytical Rigor,
Efficiency, and Effectiveness
PowerPoint Engineering
(Common Practice)
Model-Based SE
(Improved Practice)
Independent drawings
Consistent views
Static diagrams
Executable behavior
Data storage
Linked repository
Stored views
Dynamic view generation
Ad hoc process
(inconsistent results)
Repeatable process
(consistent results)
Manual change
propagation across all
affected products (by the
systems engineer)
Automatic change
propagation across all
current and future
products (by the
engineering environment)
Thank You!
For More Information
 Vitech Website http://www.vitechcorp.com/
 Community http://community.vitechcorp.com/home/
 Presenter [email protected]
We invite your comments and questions on the Community
website at http://community.vitechcorp.com/forum/