Views on Evolvability of Embedded Systems

317 Pages·2011·7.342 MB·English

by  Piërre van de Laar, Alexander U. Douglas (auth.), Pierre Van de Laar, Teade Punter (eds.)

Embedded Systems
SeriesEditors
NikilD.Dutt,DepartmentofComputerScience,ZotCode3435,DonaldBren
SchoolofInformationandComputerSciences,UniversityofCalifornia,Irvine,
CA92697-3435,USA
PeterMarwedel,TUDortmund,Informatik12,Otto-Hahn-Str.16,44227
Dortmund,Germany
GrantMartin,TensilicaInc.,3255-6ScottBlvd.,SantaClara,CA95054,USA
Forfurthervolumes:
http://www.springer.com/series/8563

Pie¨rre van de Laar Teade Punter
(cid:2)
Editors
Views on Evolvability
of Embedded Systems
123
Editors
Pie¨rrevandeLaar TeadePunter
EmbeddedSystemsInstitute EmbeddedSystemsInstitute
LaplaceBuilding0.10 LaplaceBuilding0.10
DenDolech2 DenDolech2
5612AZEindhoven 5612AZEindhoven
Netherlands Netherlands
[email protected] [email protected]
ISBN978-90-481-9848-1 e-ISBN978-90-481-9849-8
DOI10.1007/978-90-481-9849-8
SpringerDordrechtHeidelbergLondonNewYork
LibraryofCongressControlNumber:2010937425
(cid:2)c SpringerScience+BusinessMediaB.V.2011
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Foreword
Back in 2004 new markets in China, India and South America were beginningto
openupanditwasimportantforPhilipsHealthcaretomaintainitsstrongpositionin
MRImedicalscanners.ForwardthinkingpeopleatPhilipsHealthcareMRIstarted
to worry about this and how to remain competitive in an increasingly changing
world.Oneoftheproblemswastoeffectivelydealwithaconstantflowofchanges
to the system. Thesechangeswere comingin fromall kindsof sources:key tech-
nologysuppliers,customer expectations,emergingnew diagnostic techniquesand
marketpressurestoreducecost.Foranorganizationdesigningandbuildinghighly
complexmedicalimagingsystemsthiswasindeedachallenge.
Foranybusiness,stayingaheadrequiresofferinggreatproductsontime andat
competitiveprices.ToPhilipsHealthcareMRIevolvabilitymeansthattheimpactof
changeshouldbeminimalandpredictable.Forourdevelopmentorganizationthisis
akeyenablertodeliveronourcommitments.However,evenseeminglysimplehigh
levelchangescanhavearipplingeffectacrossfunctionalboundaries.Wehaveex-
periencedinthepasthowunexpectedchangepropagationcanhamperpredictability
ofourdevelopments.
Designing and building complex products like MRI scanners requires experts
frommultipletechnicaldisciplinestoworktogether.Aseachdisciplinehasitsown
way of working and its own vocabulary, communication does not always come
naturally,raisingtheneedforefficientmeansof communicatingrequirementsand
designs.
Whileapplyingchangestothesystem,erosionofthequalitiesofthearchitecture
hasproventobearealdanger.Ourarchitectswantedsystematicwaystomaintain
theintegrityofthesystemarchitecturewhilebeingabletoincorporatechangemore
easily.Thereforetheyneededasystemarchitectureanddevelopmentprocessesthat
allowforexpectedandunexpectedchange.
Oneofourstrategiestoaddressthesekindsofproblemswastoparticipateinthe
Darwinproject.AsthenamesuggestsDarwinfocusedonevolvability.Researchers
fromESI,PhilipsResearch,theTechnicalUniversitiesofDelft,Twente andEind-
hoven,theVUUniversityofAmsterdamandUniversityofGroningencametogether
inBesttoworkwithourseniorarchitectstoexplorewaysofmakingchangeeasier
andmorepredictable.Thescopeoftheprojectwaswideandcovereddifferentstages
oftheproductcreationprocess.Itaddressedverydifferentlevels,fromexposingthe
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vi Foreword
structure of our rapidly growingcode base, approaching10 million lines of code,
tomakingdecisionsonarchitectureevolutionstogetherwithmanagementandtech-
nicalstakeholders.We were shownnovelwaysof modelingand visualizationand
howthesecanbeusedtoenhancecommunicationandtomoveustowardsa‘right-
by-design’wayofworking.
This book marks the end of the Darwin project. It contains easy to read de-
scriptionsof all the researchcarried outand possible applicationareas. At Philips
HealthcareMRIweusedtheDarwinianprinciplestoevaluatetheresultsachieved.
Eachresearchtopicwascriticallyevaluatedforsuitabilityandvaluetoourorganiza-
tion.Industrialscalepilotswerecarriedoutandonlythefittesttopicswereallowed
tobeincorporatedintoourwayofworking.DespitethisharshtreatmentIamhappy
to say that significant benefits have been achieved. We have deployed techniques
and tools into our organizationthat help us to communicatebetter,to capture and
implementourowndesignideasandtopredictandanalyzecomplexsystembehav-
ior. Topics thatwere notfoundfit enoughin our setting may verywell flourish in
otherenvironments,butofcoursethatisallpartoftheDarwinstory.
We are happy with the results achieved by the Darwin project and it has once
again demonstrated the benefits to be gained from working with outside groups.
The different parties involved in Darwin have provided us with some innovative
approaches that can help us maintain our “Best-in-Class” status in MRI system
development.
April2010 FonsGijselhart
VicePresident/DevelopmentandPMOManager
MRISystems
PhilipsHealthcare
Preface
Ithasbecomea traditionthateachEmbeddedSystemsInstitute’s5yearIndustry-
as-Laboratory project is concluded with a book, bringing together the main
achievements of the research. This is now the fifth book in this series. In a way
it is also the first book, as this book is published by the international publisher,
Springer,asopposedtoourearlierbooks,whichwerepublished‘inhouse’.
This book describes the Darwin project which addressed the challenges of
designingandmaintaininglargeembeddedsoftware-basedsystems.Theindustrial
vehiclechosenfortheresearchwastheMRIscannerfamilymadebyPhilipsHealth-
care.MRI scannersarecomplex,high-value,high-endmachinesofferinga unique
detailed view of the inside of the human body. In this specialized field Philips is
a renownedworldleader.Theprojectteamwasmadeupofresearchersandarchi-
tects from the Embedded Systems Institute, Philips Healthcare, Philips Research,
TUDelft,TUEindhoven,theUniversityofTwente,theUniversityGroningenand
theVUUniversityofAmsterdam.DarwinstartedinOctober2005andranuntilthe
endofSeptember2010.
The Darwin project focused specifically on system evolvability, that is, a sys-
tem’sabilitytohandlechangestoitsrequirements,environmentandimplementation
technologies. The need to improve system evolvability is becoming increasingly
recognized, especially in the engineering of computer based systems, where the
development, commissioning and replacement of large systems can be extremely
costly.Despite thisclearindustrialneed,therearenoformalmeansforevaluating
the evolvability of systems; hence, no means of proving that one system is more
evolvable than another. The Darwin project recognized this and aimed to provide
methodsandtoolsthatwouldleadtothedesignofhighlyevolvablesystems.MRI
scanners,apartfromthecomplexityoftheirmechanicalandphysicalcomponents,
contain close to 10 million lines of code. Time to market pressures, customer de-
mands, system opennessand strict certification proceduresall increase a system’s
complexity making evolvability an important system quality. The Industry-as-
Laboratoryparadigm,pioneeredbyESI,bringstogetherresearchersfromacademia
andindustrytofocusonconcreteindustrialcasesandhasbeeninstrumentalinthis
project.Withoutthisapproach,universityresearcherswouldnothavebeenableto
validate their work, nor would they have had access to a real system’s code base.
vii
viii Preface
Conversely,theapproachhasallowedindustrialsystemdesignerstoseethemerits
ofadvancednewsoftwareandsystemdevelopmenttechniquesbeingdevelopedin
academia.
I would like to thank all participants in this project for their commitment and
contributions; as a team, they have made Darwin into a success! The support of
PhilipsHealthcareandtheDutchMinistryofEconomicAffairs(AgentschapNL),
whoprovidedthefinancialsupport,viatheBSIKfunding,forDarwin,aregratefully
acknowledged.We also thank Springer for their willingness to publish this book.
Withthisbook,theEmbeddedSystemsInstitutehopestosharethemostimportant
results and insights of the Darwin projectwith a wider audience,both in industry
andacademia.
April2010 Prof.dr.ir.BoudewijnHaverkort
ScientificDirector&Chair
EmbeddedSystemsInstitute
TheNetherlands
Acknowledgements
This work has been carried out as a part of the DARWIN project at Philips
HealthcareundertheresponsibilitiesoftheEmbeddedSystemsInstitute(ESI).This
projectispartiallysupportedbytheDutchMinistryofEconomicAffairsunderthe
BSIK program.We gratefullyacknowledgethe inputfrommanypeopleatPhilips
Healthcare MRI over the five years of the Darwin project. Special thanks go to
Philips Healthcare for organizingan Industry-as-Laboratoryproject in their com-
pany. We also thank the Philips Healthcare and Philips Research employees, our
academicpartnersandourESIcolleaguesthatwereinvolvedforreviewingthechap-
ters. Their peer reviews provided constructive feedback and improved the quality
of the book. Furthermore, we like to thank our academic partners (University of
Twente,EindhovenUniversityofTechnology,VU UniversityofAmsterdam,Uni-
versity of Groningen and Delft University of Technology), Philips Research and
Philips Healthcare for writing a variety of book chapters. This has resulted in a
bookthatshowstheviewsonevolvabilityofembeddedsystems.
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