Dtsi/SOL/

ETSI MTS meeting, Sophia Antipolis 1March 2004

Methodology

Chokri Mraidha, Sébastien Gérard

DRT-LIST/DTSI/SOL/LLSP, CEA/Saclay, F-91191 Gif sur Yvette Cedex France

Phone: +33 1 69 08 50 39 ; Fax: +33 1 69 08 20 82

Chokri.Mraidha@cea.fr, Sebastien.Gerard@cea.fr

Dtsi/SOL/

ETSI MTS meeting, Sophia Antipolis 2March 2004

Outlines

Scope: Real-time and Embedded Systems development

Problematic:public: help non-experts to design real-time systemsHow to do it ?

Manage systems complexity, Improve development quality, Make easier the maintenance…

… ensure reliability and effectiveness.

Dtsi/SOL/

ETSI MTS meeting, Sophia Antipolis 3March 2004

Contents

Outlines of the Accord/UML approach

Focus on behavioral aspect modeling

Dtsi/SOL/

ETSI MTS meeting, Sophia Antipolis 4March 2004

Accord/UML Methodology

UML component-based methodology…… in a model-driven way

Régulateur Af

ficheur Capteur

Requirements

Application

ACCORD/UML Méthodology

+ UML tools

+ ACCORD/UML Modules

System modelling

Prototyping

Application Domain : Distributed Real-time Embedded Systems

Dtsi/SOL/

ETSI MTS meeting, Sophia Antipolis 5March 2004

Outlines of the Accord/UML workbench

Document describing the Accord/UML Method

UML profile for SPT« Profile »

UML profile for ACCORD/UML« Profile »

UML profile forACCORD/UML Process

« Profile »UML profile for

ACCORD/UML PAM« Profile »UML profile for

ACCORD/UML DAM« Profile »UML profile for

ACCORD/UML PrM« Profile »

« use »

User guide forAccord/UML profilesunder Objecteering

Virtual Machine

Kernel

Accord Framework

« implement »

ACCORD_UML_Process.prof« ProfileImplementation »ACCORD_UML_PAM.prof

« ProfileImplementation »ACCORD_UML_DAM.prof« ProfileImplementation »ACCORD_UML_PrM.prof

« ProfileImplementation »

Methodology entirely based on UML

Dtsi/SOL/

ETSI MTS meeting, Sophia Antipolis 6March 2004

Several modeler points of view

System models struct. based on dev. cycle

System Analyst

PAM,

Preliminary Analysis

Rules

Req. Doc.

ACCORD/UML

PAM

System Analyst

DAM,

DAM

Detailed AnalysisRules

ACCORD/UML

Spec. Valider

VaM,

Validation Rules

ACCORD/UML VaM

Prototyper

PrM, TeM…

Prototyping Rules

ACCORD/UML

PrM

TeM

Testing Rules

ACCORD/UML

Accord/UML profile

ACCORD/UML

Dtsi/SOL/

ETSI MTS meeting, Sophia Antipolis 7March 2004

Preliminary analysis Model

Purpose « Formalize » requirementsPrinciple

The system is viewed like a “black box”.Contents

a dictionaryto have/to take the target domain in hand

a use-case diagram functionalities clear identification of frontiers

high level scenarios communication protocol between the Syst. and Env.

With real-time constraints

Dtsi/SOL/

ETSI MTS meeting, Sophia Antipolis 8March 2004

Detailed Analysis Model

Three well-funded and complementary model Structural, behavioral, interaction

A component based architecture ( model level)Separation of behavioral aspect

Control aspect UML protocol state machine on classes

Algorithmic aspect Activity diagrams Action language for operations

Support of high level concurrency Real-Time Object

Various communication models Strong or postponed synchronous, asynchronous or diffusion

Refinement of Real-Time constraints

Dtsi/SOL/

ETSI MTS meeting, Sophia Antipolis 9March 2004

Prototyping model

Component-based modelThe system = a componentPossibility of importing binary components

E.g. graphical interface component, mathematical component…

Assembly of componentsDefinition of mechanisms for an automatic integration

at model level or at code level

Complete generation of code (structure + behavior)

Include action language and associated code generators

Targets: Unix, Linux and VxWorks operating systems

Dtsi/SOL/

ETSI MTS meeting, Sophia Antipolis 10March 2004

Validation model

Validation by exhaustive testing through symbolic execution definition of model transformations towards a formal tool called AGATHA that:

calculate in an exhaustive way the dynamic behavior generate automatically tests thanks to a symbolic

execution verify if PAM and DAM sequence diagrams are compatible

with the set of calculated diagrams of AGATHA

Ongoing PhD on schedulability analysis of UML models

Dtsi/SOL/

ETSI MTS meeting, Sophia Antipolis 11March 2004

Contents

Outlines of the Accord/UML approach

Focus on behavioral aspect modeling

Dtsi/SOL/

ETSI MTS meeting, Sophia Antipolis 12March 2004

tgSpeed : intinitReg()stopReg()display()

Regulator

C

Off On

initReg[cptVit->getSpeed()=<30] /display("ON");

stopReg/display("OFF");

tm(100)/tgSpeed = cptVit->getSpeed();

[carSpeed=<30]/display("OFF");

/delta=k1*atan(tgSpeed-cuSpeed);mot->sendCmd(coupleVariation);

ControlControl AlgorithmicAlgorithmic&

The Behavioral Aspect: Common Approach

Usual form of UML state machine

E1 E2

‘Evt’ ‘[’ guard ‘]’ / ‘procedure’List of actions

Sample of usage

Issues related to this situation Maintainability because of different aspects combination Reusability because of state-machine inheritance issues

Dtsi/SOL/

ETSI MTS meeting, Sophia Antipolis 13March 2004

Regulator

+tgSpeed : integer+initReg()+stopReg()+maintainSp()

Off On

initReg()

stopReg()

maintainSp()

Class Behaviour Model=

Logic aspect of behaviour

Activity – “describe behavioral view”M

eth

od B

ehav

iou

r M

ode

l =

Alg

orit

hmic

asp

ect o

f beh

avio

r

carSpeed = cptVit.getSpeed()

mot.sendCmd(coupleVariation)

delta=k1*atan(tgSpeed-cuSpeed)

New operation introduced to integrate algorithmic aspect

Advantages of this proposition Maintainability because of separation of concerns Reusability because of availability of usual OO inheritance mechanisms

UML2 protocole state machines UML2 protocole state machines

… An action language definition… An action language definition

Dtsi/SOL/

ETSI MTS meeting, Sophia Antipolis 14March 2004

Conclusions

Accord/UML methodology gives an executable UML modelA complete and clear behavioral model

Separation of logic and algorithmic aspectsAn action language for operations modeling

Model executability allowsValidation at every stage of the developmentPerformance analysis at the model levelA full customization of code generation to a specific

platform optimized code generation a better reusability of models a better maintability

A standard UML executable model still needs a standard action language notation mapping the action semantics syntax defined in UML 2.0

Dtsi/SOL/

ETSI MTS meeting, Sophia Antipolis 15March 2004

Web sites associated to the subject 

http://wooddes.intranet.gr

www.acotris.c-s.fr

www.systemes-critiques.org/ARTIST

www.east-eea.net

www.carroll-research.org

www.topmodl.org

http://www-drt.cea.fr/acclist.htm

« MDA and DRES summer School »

http://sancy.ensieta.fr/mda« SIVOES-SPT workshop on feedback on SPT profile »

http://www.cs.virginia.edu/rtas04« SIVOES – MoDeVa workshop on Modelling, Design and Validation »

http://www.issre.org/2004