Beginners Guide to Model-Based Systems Engineering

12/18/2018

Key Semantics of State Transition Diagrams, cont.

• Triggering events for transitions • Guard conditions (in brackets) • Type

• Call – EventName (condition) • Signal – EventName (condition) • Change – when condition

• Absolute Time – at condition • Relative Time – after condition • Service function for transition • Related behavior shown after triggering event information

Additional information available in Chapter 11 of A Practical Guide to SysML

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stmGeospatialLibrary

Mapping State Transition Diagrams

TurnOff

idle

shuttingdown

ShutdownConfirmed /ShutDownCameras

after 60 s / Display "Timed Out"Status

Startup

elicits

Shutdown [in (loggedon)] / Confirm Shutdown Request

Requirement

Use Case

elaboratedby

initializing

refinedby

basedon / specifiedby

verifiedby

[init ok]

specifiedby

includes/ extends/ kindof

operating

SystemOK

[not initOK]

Verification Requirement

entry/Display "Operating"Status do/OperateGeospation Library exit/Display Status

verifiedby

fulfilledby

involves/ describes

Maintenance [in (loggedon)] / Confirm Maintenance Request

executedby

diagnosing

Verification Event

SystemOK

Resource

employs

includes

maintenance

Test Configuration

Test Activity

captures/ consumes/ produces

MaintenanceCompleted

formedby

Test Procedure

decomposedby

Component

Function

performs

Level of Detail: Medium Audience: System and software engineers Content: System states and the corresponding transitions Use: Insight into the system by taking an orthogonal look at behavior

incorporates

exhibits

exitsby

built from / kindof

exposes

decomposedby

joined to

State

enters

exitedby

inputs/ outputs/ triggeredby

Exit

Interface

Port

decomposedby

includes

comprisedof

Event

Transition

responsible for

connectsto

triggeredby

Link

Item

transfers

includes

decomposedby

constrains/ usesparameter from

generates

results in

causes

assignedto

Organization

Constraint Definition

Concern

Risk

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