1. From SADT to SysML:
formulation of an embedding
pascal.roques@gmail.com ICSSEA , 07/12/2010

2. Speaker: Pascal Roques
 Senior Consultant, >20 years modeling experience
• SADT,
• OMT, UML, SysML
 Co-founder and chairman of
 Author of several best-seller UML books in French
 … and of the first French SysML book
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3. The past: SADT and ASA™ (1/2)
 SADT: Structured Analysis and Design Technique
• Diagrammatic notation designed specifically to help people describe
and understand systems
• Boxes and arrows
with informal semantics
• Top-down functional breakdown
• Received extensive use starting in 1973 by the US Air Force
Integrated Computer Aided Manufacturing program
• In 1981, IDEF0 formalism was published, based on SADT
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4. The past: SADT and ASA™ (2/2)
 ASA™: Automata and
Structured Analysis (Verilog)
• Enhanced SADT with dynamics
description by means of Finite
State Machines
 Formalization of communication
arrows
 Dynamic description of the leaf
functions in terms of states, events,
actions and conditions (LSA
language)
• Provided tools, not only for
edition and documentation
generation, but also simulation
and even test generation
 applied intensively on industrial
projects, mainly in: aeronautics,
ground transport and space
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5. The present: SysML™ (OMG)
 General-purpose graphical modeling language for
specifying, analyzing, designing, and verifying complex
systems that may include hardware, software,
information, personnel, procedures, and facilities
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6. Possible SADT/SysML mappings (1/3)
 SADT: A-0 Context Diagram
• Describes the environment of the system seen as a black box
 SysML Internal Block
Diagram
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7. SysML Complementary Diagrams (1/2)
 SysML Block Definition Diagram
 SysML Use Case Diagram
 SysML Sequence Diagram
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8. Possible SADT/SysML mappings (2/3)
 SADT: A0 Diagram
• Shows the first breakdown level of the system into functions
 SysML Internal Block
Diagram
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9. Possible SADT/SysML mappings (3/3)
 SADT: A0 Diagram
 SysML Activity Diagram
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10. SysML Complementary Diagrams (2/2)
 SysML Block Definition Diagram
 SysML Sequence Diagram
 SysML State Machine Diagram
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11. Summary: SADT/SysML
SADT SysML
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12. Conclusion
 SADT provides only two different types of diagrams, enabling
simple communication
• But this is paid by a lack of expressivity that can be really a problem
for complex systems
 On the contrary, SysML offers nine different types of
diagrams and is then much richer!
• SysML is just a modeling language, not a method
 A systematic translation from SADT models to SysML models
can be envisaged, even if some theoretical points are still
debatable
• Main issue: are SADT functions mostly structural (SysML blocks) or
mostly behavioral (SysML activities and actions) or both?!
• Work in progress with Obeo Designer
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