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Requirement Concepts Modeling Focus Team


  • Sandy Friedenthal - SAF Consulting
  • John Watson
  • Rick Steiner - Skygazer Consulting
  • Tao Yue - Simula
  • Shaukat Ali - Simula
  • Brian Selvy - LSST
  • Bertil Muth - Hood Group
  • David Haines - Boeing
  • Michael Crow - Boeing


The objective of the team is to establish the set of requirements for a comprehensive concept model of Requirements and Verification for SysML V2.

Starting Point

SE Needs Reference Material

Latest Working Documents

Limitations of SysML v1

  • See section 1.2 of the Requirement/Verification Needs document.

Driving Requirements

(R1) The next-generation modeling language must express the core systems engineering concepts. This requires definition of a robust data model that reflects these concepts. The requirements that drove SysML derive from the original Systems Engineering Conceptual Model, jointly developed by the INCOSE/OMG/AP233 WG requirements team. Modifications and refinements to this model will occur in light of lessons learned over the last several years, and as necessary to express the core systems engineering concepts.

Requirements Analysis

2. Propose updates to draft requirements attributes and categories in current concept model for consideration to be included within SysML v2 – Bertil Muth

3. Review requirements relationships in current concept model and propose a draft taxonomy and definition of relationships for SysML v2 – Rick Steiner and Brian Selvy

4. Propose how uncertainty should be addressed in SysML v2 using the current concept model and starting with the weight requirement example (Requirements/Verification SECM Concept Diagrams, slides 7-9) - Tao Yue and Shaukat Ali

  • Completed - Actions listed below have been closed - Sandy asked for feedback to Tao and Shaukat proposed approach to deal with requirements uncertainty that they presented at the 23 Nov telecom. Sandy proposed the following:
    1. Include a non-normative requirement in the SysML v2 RFP for a structured natural language text requirements that incorporates concepts of uncertainty. Refer to Tao/Shaukat’s approach as a potential solution.
    2. Treat the general issue of uncertainty more generally than requirements alone. Focus initially on the uncertainty of property values. Ensure the ability to distinguish different types of uncertainty, such as the uncertainty associated with unit to unit variation (e.g., uncertainty of weight of different manufactured systems) and the uncertainty associated with a property over time due to many different system and environmental uncertainties (e.g. variation in fuel efficiency or engine temperature for a particular vehicle over time)
    3. Action: Tao/Shaukat confirm this is an acceptable proposal - Closed, Tao responded “It is a good proposal. We accept it.”
    4. Action: If confirmed, John to add this requirement and add Tao/Shaukat Structured Natural Language metamodel into the concept model as an example - Closed
    5. Action: Sandy coordinate with Hans Peter to ensure probabilities are sufficiently addressed in the Properties and Expressions concepts - Closed

5. Propose how current concept model can support scenario based requirements using natural language starting with the behavior example (Requirements/Verification SECM Concept Diagrams, slide 12) – Tao Yue and Shaukat Ali

6. Contrast the approaches to Structured Natural Language Requirements approaches – Tao Yue and Shaukat Ali

7. Discuss Bjorn Cole feedback regarding embedding the required properties and constraints in a block. Sandy Friedenthal

8. Assess the mapping between SysML v2 concepts and ReqIF concepts, and provide recommendations for potential future alignment – Bertil Muth

9. Review the integration concepts and their relationship to the verification concepts – Brian, David

  • Meeting discussion date TBD

Derived Requirements


sysml-roadmap/requirement_concepts_modeling_core_team.txt · Last modified: 2017-03-12 12:13 by jwatson