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--- bok:eng:mbse:method [2020/09/10 04:43]
anwlur [Survey of MBSE Methodologies] added FAS
+++ bok:eng:mbse:method [2020/09/17 14:17]
anwlur [JPL State Analysis (SA)] added dev activities
@@ Line 9: / Line 9: @@
   * 2010 revision to Harmony/SE
   * 2nd edition for Vitech MBSE Methodology (released 2011)
+  * 2012 release of JPL SA
   * inclusion of SYSMOD
   * inclusion of Functional Architecture for Systems
@@ Line 229: / Line 230: @@
   - Validation & Verification
 ==== JPL State Analysis (SA) ====
+Sources for this methodology include
+  * 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]].
+JPL State Analysis...
+  * provides a methodology to design complex control systems
+  * Typical architecture is as below
+{{ :bok:eng:mbse:method:jpl_sa1.png?500 |}}
+  * Mission Planning & Execution supplies Control Goals to State Control
+  * Mission Planning & Execution supplies Knowledge Goals to State Estimation
+  * State Estimation supplies State Functions :?: to State Knowledge
+  * State Knowledge supplies State Values to State Control
+  * Models bridges State Estimation, Knowledge and Control
+  * State Control supplies Commands to Hardware Adapter
+  * Sense (sensors) and Act (actuators) are ports to Hardware Adapter. Hardware Adapter is child to System Under Control
+  * Actuator creates changes which influences Sensors
+  * Hardware Adapter supplies Measurements & Commands to State Estimation
+=== Rationale ===
+  * 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
+=== Objectives ===
+  * Facilitates system engineers to precisely express design intent in a tool that actively ensures consistency
+  * Clear distinction between Control System and System Under Control
+  * 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
+    * Describing methods by which objectives will be achieved
+=== 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
+  - Goals are elaborated as (typically) stereotyped use cases whilst the temporal aspect of goals is defined as constraints and analysed in parametric diagrams.
 ==== Object-Process Methodology (OPM) ====

Model of Knowledge by Fitzgerald Systems

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