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bok:eng:mbse:method
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bok:eng:mbse:method [2020/09/10 08:19] anwlur [Survey of MBSE Methodologies] added gap to 2012 release of JPL SA |
bok:eng:mbse:method [2020/09/18 10:38] (current) anwlur [JPL State Analysis (SA)] |
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| * D. Wagner, "An Ontology for State Analysis: Formalizing the Mapping to SysML", IEEE (2012). Accessed on September 10th, 2020 [[http://www.omgsysml.org/State_Analysis_Ontology%20_in_SysML.pdf|here]]. | * D. Wagner, "An Ontology for State Analysis: Formalizing the Mapping to SysML", IEEE (2012). Accessed on September 10th, 2020 [[http://www.omgsysml.org/State_Analysis_Ontology%20_in_SysML.pdf|here]]. | ||
| * D. Wagner, "An Ontology for State Analysis: Formalizing the Mapping to SysML", Presentation to IEEE Aerospace Conference (March 2012). Accessed on September 10th, 2020 [[https://trs.jpl.nasa.gov/bitstream/handle/2014/42601/12-0881.pdf|here]]. | * D. Wagner, "An Ontology for State Analysis: Formalizing the Mapping to SysML", Presentation to IEEE Aerospace Conference (March 2012). Accessed on September 10th, 2020 [[https://trs.jpl.nasa.gov/bitstream/handle/2014/42601/12-0881.pdf|here]]. | ||
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| + | JPL State Analysis... | ||
| + | |||
| + | * provides a methodology to design complex control systems | ||
| + | * Typical architecture is as below | ||
| {{ :bok:eng:mbse:method:jpl_sa1.png?500 |}} | {{ :bok:eng:mbse:method:jpl_sa1.png?500 |}} | ||
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| * Mission Planning & Execution supplies Control Goals to State Control | * Mission Planning & Execution supplies Control Goals to State Control | ||
| * Mission Planning & Execution supplies Knowledge Goals to State Estimation | * Mission Planning & Execution supplies Knowledge Goals to State Estimation | ||
| - | * State Estimation supplies State Functions (?) to State Knowledge | + | * State Estimation supplies State Functions :?: to State Knowledge |
| * State Knowledge supplies State Values to State Control | * State Knowledge supplies State Values to State Control | ||
| * Models bridges State Estimation, Knowledge and Control | * Models bridges State Estimation, Knowledge and Control | ||
| Line 247: | Line 252: | ||
| * Actuator creates changes which influences Sensors | * Actuator creates changes which influences Sensors | ||
| * Hardware Adapter supplies Measurements & Commands to State Estimation | * Hardware Adapter supplies Measurements & Commands to State Estimation | ||
| - | |||
| - | JPL SA ... | ||
| - | |||
| - | * provides a methodology to design complex control systems | ||
| - | * extends basic concepts from control theory and software architecture | ||
| === Rationale === | === Rationale === | ||
| - | * As system complexity grown it is not possible to manage a system based on subsystem-level functional decomposition, the web of interactions are too great | + | * As system complexity grows it is not possible to manage a system based on subsystem-level functional decomposition, the web of interactions are too great |
| * There is a gap between requirements on SW specified by system engineers and the implementation of these requirements by software engineers, leaving open the possibility of misinterpretation of system engineer's intent | * There is a gap between requirements on SW specified by system engineers and the implementation of these requirements by software engineers, leaving open the possibility of misinterpretation of system engineer's intent | ||
| Line 262: | Line 262: | ||
| * Facilitates system engineers to precisely express design intent in a tool that actively ensures consistency | * Facilitates system engineers to precisely express design intent in a tool that actively ensures consistency | ||
| * Clear distinction between Control System and System Under Control | * Clear distinction between Control System and System Under Control | ||
| - | * Model of System Under Control must be explicitly identified and used in a way that assures consensus | + | * Provide a methodology for |
| - | * | + | * Discovering and documenting states of a system |
| - | + | * Modeling behavior of state variables and relationships between them | |
| - | + | * Capturing mission objectives in detailed scenarios motivated by operator intent | |
| - | + | * Keep track of system constraints and operating rules | |
| - | * Unordered List Item | + | * Describing methods by which objectives will be achieved |
| - | * Make system intent explicit in the design and implementation | + | |
| - | * Controllers use state estimates as inputs - not direct measurements | + | |
| - | * Single controller per state variable | + | |
| - | * Single estimator per state variable | + | |
| - | + | ||
| - | === Example === | + | |
| - | + | ||
| === Development Activities === | === Development Activities === | ||
| + | - The foundation of the JPL SA methodology is the control system and the //system under control// are explicitly different. This separation is formalized in an //ontology// which is written in OWL2. JPL used [[https://protege.stanford.edu/|Protege]] as the editing environment. | ||
| + | - This ontology is mapped to SysML artifacts using Query/View/Transformation (QVT), a model-to-model transformation standard by OMG. | ||
| + | - A context diagram (block diagram) includes //Analysis Context// with parts //System Under Control// and //Control System// | ||
| + | - In a state effects diagram (=internal block diagram) map the relationship between different state variables contained within the context. Use //affects// and //affectedBy// relationships. | ||
| + | - Define mathematical relationships between State Variables with parametric diagrams | ||
| + | - Control System is designed. A State Variable has only 1 //Controller// and (may) have only one //Estimator// | ||
| + | - The //HardwareAdapter// is modeled to be an interface between the Control System and System Under Control. Measurements flow from System Under Control to Control System, Controls flow the other way. | ||
| + | - Goals are elaborated as (typically) stereotyped use cases whilst the temporal aspect of goals is defined as constraints and analyzed in parametric diagrams. | ||
| ==== Object-Process Methodology (OPM) ==== | ==== Object-Process Methodology (OPM) ==== | ||
| ==== SYSMOD ==== | ==== SYSMOD ==== | ||
| + | |||
| + | ==== Funcational Architecture Methodology ==== | ||
| + | |||
bok/eng/mbse/method.1599725978.txt.gz · Last modified: 2020/09/10 08:19 by anwlur
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