Software-intensive medizinische Systeme stehen in einem immensen Marktdruck. Während sie technologisch und hinsichtlich ihrer Sicherheit kompromisslos innovativ sein müssen, fordern die Krankenhäuser und auch Gesundheitskostenreformen eine immer kürzere Zykluszeit bei gleichzeitig angespannten Budgets. Traditionelle Entwicklungsprozesse, die Innovation und Qualität über einen schwerfälligen Prozess erreichten, sind nicht mehr zeitgemäß. Unsere Studien zeigen, dass in der Medizintechnik die Kosten für Nacharbeiten über den Produktlebenszyklus hinweg durch eine Verbesserung des Requirements Engineering um 30-50% gesenkt werden können. Requirements Engineering hat daher eine Schlüsselstelle als Erfolgsfaktor im Gesundheitswesen. Modellbasierte Vorgehensweisen unterstützt die durchgängige Entwicklung von Anforderungen bis zur Validierung. Durch den erhöhten Abstraktionsgrad zu Beginn bei der anforderungsentwicklung und Analyse sind Problembeschreibungen wesentlich klarer, einfacher und weniger redundant. Das erhöht nicht nur die Entwicklungsgeschwindigkeit, sondern sorgt innerhalb des Projektes für klar verstandende Domänenkonzepte. Modelle helfen bei der Durchgängigkeit von den systemanforderungen zu den Softwareanforderungen und dann zu Design und Validierung. Unser Beitrag zeigt Industrieerfahrungen bei Siemens Healthcare und bietet Orientierung bei der Umsetzung modellbasierter Entwicklung mit Fokus auf Requirements Engineering in medizinischen Systemen. Wir zeigen, wie Anforderungen so formalisiert werden, dass einerseits informell formulierte Anforderungen schrittweise in eine formalere Form kommen und während die Verständlichkeit der Anforderungen erhalten bleibt. Damit sind die Anforderungen präzise formuliert und werden zur Konsistenzsicherung und Vervollständigung genutzt, und sie können weiterhin von Stakeholder verschiedenem Hintergrund verstanden und validiert werden.
2. Contents
Goals
Brief look on Siemens Healthcare
Business challenges
Model-based Engineering: Issues & Solutions
Recommendations
Further Information
2012 Siemens Healthcare Diagnostics Inc. Page 2
3. Contents
Goals
Brief look on Siemens Healthcare
Business challenges
Model-based Engineering: Issues & Solutions
Results and Summary
Further Information
2012 Siemens Healthcare Diagnostics Inc. Page 3
4. Goals of this Talk
Share the experiences using
models in engineering gained
at Siemens Healthcare
Discuss challenges, needs
and requirements to advance
model-driven product
development
Show the concrete value of
model-based engineering
2012 Siemens Healthcare Diagnostics Inc. Page 4
5. Contents
Goals
Brief look on Siemens Healthcare
Business challenges
Model-based Engineering: Issues &
Solutions
Results and Summary
Further Information
2012 Siemens Healthcare Diagnostics Inc. Page 5
6. Siemens Healthcare
In vivo diagnostics (imaging)
X-Ray Computed Magnetic Molecular Ultrasound Oncology
Tomography Resonance Imaging
IT Solutions
In vitro diagnostics (laboratory systems)
Immunoassay Molecular Clinical Chemistry Hematology Urinalysis Lab Automation Point of Care
2012 Siemens Healthcare Diagnostics Inc. Page 6
7. Vector Consulting Services
Your Partner in Achieving Engineering
Excellence
… offers a comprehensive consulting, tools
and training portfolio for optimizing technical Automotive
product development
… serves industries such as automotive, Aviation &
Defense
aviation, IT and telecom, energy and
environment, medical and railway
IT &
Telecom
… is supporting clients worldwide on
efficiency improvement, requirements
engineering, ALM/PLM, systems Energy &
Environment
engineering, product management, interim
management, and organizational change
Medical &
… as a group serves companies across the Healthcare
world with over 1000 employees and sales
of well over 150 Mio € pa Railway &
Transportation
www.vector.com/consulting
2012 Siemens Healthcare Diagnostics Inc. Page 7
8. Contents
Goals
Brief look on Siemens and Vector
Healthcare
Project syngo.via
Business Challenges
Business challenges Issues & Solutions
Model Management:
Lean Requirements Engineering
Results and Summary
Results Information
Further and Summary
Further Information
2012 Siemens Healthcare Diagnostics Inc. Page 8
9. Business Challenges in Medical Device
Industry
Focus of this talk
Platforms
Sources: [1, 2, 5]
Application Life-cycle Model-based
Management Tools Globally Integrated Engineering and Reuse
Engineering
Systems
2012 Siemens Healthcare Diagnostics Inc. Page 9
10. Typical Large-Scale Medical Device
Projects
Project Context
Several thousand single
product requirements
Several million lines of code
Several hundred developers
in many locations worldwide
Many fold clinical
applications
Source: H IM
2012 Siemens Healthcare Diagnostics Inc. Page 10
11. Disclaimer:
The content discussed in this presentation needs
to be considered as work in progress.
2012 Siemens Healthcare Diagnostics Inc. Page 11
12. Contents
Goals
Brief look on Siemens and Vector
Project syngo.via
Business challenges
Business challenges
Model-based Engineering: Issues & Solutions
Lean Requirements Engineering
Results and Summary
Results Information
Further and Summary
Further Information
2012 Siemens Healthcare Diagnostics Inc. Page 12
13. Industry Issues and Pain Points
Pain Points Business Impact
Intransparent product Technology-driven product platform, no link to business
structure, domain drivers
model partially incomplete Non-transparent relationship between problem & solution space
Re-scoping sessions with customers on basis of many specs.
Ambiguity and lack of Textual-based specifications are subject to interpretation
accuracy in specifications Textual use case descriptions work only for smaller projects
Natural language subject to interpretation, inconsistent, incomplete
Growing architecture Redundancy of architecture components due to lack of
complexity understanding of problem- and solution space
Business needs not consistently linked to features
Too much variability in software architecture
Insufficient verification and Test specifications in natural language are
validation efficiency executed in a manual way only
Thousands of pages of requirements to transform
Test cases manually created
2012 Siemens Healthcare Diagnostics Inc. Page 13
14. Overview:
Solutions along the Life-Cycle
A) Requirements Meta-
Model
B) Feature D) Architecture Model E) Model-based
Model Mapping System Test
C) Graphical Modeling of
Clinical Workflows
Source: H IM
2012 Siemens Healthcare Diagnostics Inc. Page 14
15. Pain point 1: Intransparent Product
Structure
Solutions:
Selected issues:
Non-transparent relations A. Requirements Meta-model
between problem- & solution B. Feature Model
space
Re-scoping sessions w/
Source: H IM
customer on basis of many
engineering specs.
2012 Siemens Healthcare Diagnostics Inc. Page 15
16. Solution A:
Requirements Meta Model
Problem Space DB Characteristics:
Stakeholder Provides needed artifacts, their
Business Plan Request
Market Analysis, attributes and relationships to each
SW Platform Roadmap,
Business Case, etc.
input for other.
input for Using meta-model, it is also possible to
prescribe the way how / which data are
MRS
SW Feature
Analysis captured .
Market analyzed Use Case Specifications,
Requirement by Load Profiles, Benefits:
Concept Papers
Lean artefact infrastructure, no
redundancy
SW Req.
SWRS
(Problem) Guidance for engineering tasks
SW Req. with structured input
(Solution)
Established link between business
Source: H IM
Specification/
Structural Element Content
Mapping or drivers, requirements, design and
Document Input
test
2012 Siemens Healthcare Diagnostics Inc. Page 16
17. Solution B: Feature Model
Characteristics:
Highest Level of Feature Model Hierarchical tree to describe the
structure, dependencies and
commonalities
Lays out the basics for variant
management and impact analysis
Benefits:
Higher level abstraction of grouping
of requirements into sellable units:
From 5,000 product requirements
to 800+ features (factor ~ 6)
Visual domain model for healthcare
workflows (tree & graphical)
Graphical View
Reduction in time to understand
Source: H IM
Hierarchical View
aspects of the system
2012 Siemens Healthcare Diagnostics Inc. Page 17
18. Solution B:
Feature Model & Its Relations (1)
Stakeholder Requests Application Use Cases
How can I manage
huge amounts of
Requirements?
How do I scope a
product version
efficiently?
Architecture Model
Source: H IM
2012 Siemens Healthcare Diagnostics Inc. Page 18
19. Solution B:
Feature Model & Its Relations (2)
Stakeholder Requests Application Use Cases
How do I manage
Architecture Model
stakeholder requests
from different
businesses most
effectively?
Source: H IM
2012 Siemens Healthcare Diagnostics Inc. Page 19
20. Pain point 2: Ambiguity and Lack of
Accuracy of Specifications
Level Requts. Manually Manual test
Object Embedded graphs case creation
Issues:
Textual use case descriptions work only
Document Req. 1 Picture / diagram
for smaller projects < ~ 100
(text)
requirements
Natural language subject to Features Req. 2 Picture / diagram
interpretation, usually inconsistent, (text)
incomplete with incorrect version (and
conflicting) Paragraph Req. 3 Picture / diagram
(text)
Root causes:
Textual requirements engineering do not
scale for platform projects Solutions:
Missing versioning
No direct access to single requirements C. Graphical Modeling of
Lack of product structure Clinical Workflows
Inconsistently executed change
management process
Source: H IM
2012 Siemens Healthcare Diagnostics Inc. Page 20
21. Solution C:
Graphical Modeling of Clinical Workflows (1)
Characteristics:
Used to describe clinical workflows that
consist of a collection of steps in a defined
sequence together with accompanying
specification of pre-/post-conditions,
business rules, performance aspects, etc.
Benefits:
Increase expressiveness of clinical
workflows to describe dynamic behaviors
of clinical workflows
Early analysis of stakeholder requests
from customers
Improved impact analysis of change
requests
Joint modeling sessions to describe the
Source: H IM
needs from the customer‘s point of view
2012 Siemens Healthcare Diagnostics Inc. Page 21
22. Solution C:
Graphical Modeling of Clinical Workflows (2)
Stakeholder Requests Application Use Cases
How can I analyze a Model
Architecture
feature or a
stakeholder request?
Source: H IM
2012 Siemens Healthcare Diagnostics Inc. Page 22
23. Pain point 3: Growing Architecture
Complexity
Selected issues: Solutions:
Business needs not consistently
linked to features/ requirements; D. Architecture Model Mapping
dependencies between features not
easily visible
Source: H IM
Too much variability in software
architecture
2012 Siemens Healthcare Diagnostics Inc. Page 23
24. Solution D:
Architecture Model Mapping
F Feature Model Characteristics:
F F F
Identifies links between features and their
implementation
SWF SWF SWF SWF SWF SWF SWF
Explicit modeling of variability in the architecture
S Architecture Model
Benefits:
SS SS SS
Architectural decisions motivated by features
C C C C C C
and product-line variability
Enabling reduction of architectural complexity
Support impact analysis for (de-) scoping
sessions
Early identification of architectural risks
Improved accuracy of early effort estimates
Source: H IM
Reduction of number of scoping sessions
2012 Siemens Healthcare Diagnostics Inc. Page 24
25. Pain point 4: Insufficient Verification and
Validation Efficiency
Issues:
Test cases often manually Solutions:
generated from prose use cases
Cycle times for system test too E. Model-based System Test
long
Source: H IM
2012 Siemens Healthcare Diagnostics Inc. Page 25
26. Solution E:
Model-based System Test (1)
Benefits:
Early identification of requirements
defects through validation by testers
Effort reduction for test (cycle time,
cost ~ -30%) and increase of test
coverage (*)
Decrease number of defects
Model-based testing is highly
structured, reproducible and efficient
Increase reuse of development
artifacts
Quicker impact analysis by parsing
model for late requirements changes
Source: H IM
(*) Based on experience from other projects
2012 Siemens Healthcare Diagnostics Inc. Page 26
27. Solution E:
Model-based System Test (2)
Stakeholder Requests Application Use Cases
Architecture Model
Which application
use case is covered
by which test case?
Source: H IM
2012 Siemens Healthcare Diagnostics Inc. Page 27
28. Contents
Goals
Brief look on Siemens and Vector
Project syngo.via
Business challenges
Business challenges
Model-based Engineering: Issues & Solutions
Lean Requirements Engineering
Results and Summary
Results Information
Further and Summary
Further Information
2012 Siemens Healthcare Diagnostics Inc. Page 28
29. Major Changes to Development for
Model-based Engineering
A) Requirements Meta-
Model
B) Feature D) Architecture Model E) Model-based
Model Mapping System Test
C) Graphical Modeling of
Clinical Workflows
Source: H IM
2012 Siemens Healthcare Diagnostics Inc. Page 29
30. Benefits from Model-based Engineering
Feature models can help to reduce detail of product requirements
through abstraction (~ factor 6) [6]
Reduction of review times by ~ 40% using graphical modeling of
product requirements [9]
Reduction of analysis time for requirements changes
Model-based testing reduces testing effort by ~ 30% through
automation
Reduction in overall cycle time for development projects driving more
efficiency [3, 6]
2012 Siemens Healthcare Diagnostics Inc. Page 30
31. Experiences with Introducing Model-
based Engineering
Model-based engineering means a huge organizational change. Only
10% of organizations in medical have moved that road so far [10]
Modeling competence of product managers and requirements
engineers needs to be built up step-by-step thereby facilitating
acceptance
Seamless model-driven engineering needs adequate tools support.
Continuous assessment and
verification of business benefits Processes
for model-based engineering is
mandatory to maintain sponsorship.
Model-based
Engineering
Tools Persons
2012 Siemens Healthcare Diagnostics Inc. Page 31
33. Contents
Goals
Brief look on Siemens and Vector
Project syngo.via
Business challenges
Business challenges
Model-based Engineering: Issues & Solutions
Lean Requirements Engineering
Results and Summary
Results and Summary
Further Information
Further Information
2012 Siemens Healthcare Diagnostics Inc. Page 33
34. References
1. US Food & Drug Administration, Design Control Guidance for Medical Device Manufacturers; March 11, 1997
2. US Food & Drug Administration, Quality System Regulation,; January 1, 1997, http://www.fda.org/cdrh/qsr/01qsreg.html
3. Brian Berenbach, Daniel Paulish, Arnold Rudorfer, Juergen Kazmeier, Software Systems Requirements Engineering; Mc-
Graw Hill 2009; http://www.mhprofessional.com/product.php?isbn=0071605479
4. Renate Loeffler: Formal Scenario-based Requirements Specification and Test Case Generation in Healthcare
Applications, Diplomarbeit, Univ. Paderborn, 10/2009
5. Medical Device & Diagnostic Industry 101, Carey Smoak, Roche Molecular Systems Inc., Pleasonton, CA, Pharma SUG
2010, Paper 1B01
6. Arnold Rudorfer, Christof Ebert: Lean Requirements Engineering in Medical Systems, MedConf 2010, Munich, Germany,
October 14, 2010; http://2010.medconf.de/downloads/abstracts2010/T2_T3_V1_vector_siemens.pdf
7. Arnold Rudorfer, Christof Ebert: Quality Requirements Engineering in in Medical Systems, OOP11, Munich, Germany,
January 27, 2011 http://www.sigs.de/download/oop_2011/downloads/files/Do2-
3_Ebert_Rudorfer_Update_QualityRE_OOP2011.pdf
8. Arnold Rudorfer: Model-based Engineering in Medical Device Development – Issues & Solutions, INCOSE Workshop,
Phoenix, AZ, USA, January 31, 2011,
http://www.omgwiki.org/MBSE/lib/exe/fetch.php?media=mbse:2011iw_incose_modelmanagement_rudorfer.pdf
9. Brian Berenbach: Comparison of UML and Text based Requirements Engineering,
http://www.cs.helsinki.fi/u/vjkuusel/docs/Comparison%20of%20UML%20and%20text%20based%20requirements%20engi
neering%20Brian%20Berenbach.pdf
10. Christian Denger, Raimund Feldman: State of the Practice in Software Development for Medical Device Production,
Fraunhofer Institute Experimentelles Software Engineering, February 2007
2012 Siemens Healthcare Diagnostics Inc. Page 34
35. Arnold Rudorfer
Program Manager System Platform
Siemens Healthcare Diagnostics
62 Flanders-Bartley Road
Flanders, NJ, 08736 (U.S.A.)
Phone: +1 973 927 28 28 ext. 4732
Cell: +1 609 954 2384
Email:
arnold.rudorfer@siemens.com
2012 Siemens Healthcare Diagnostics Inc. Page 35
37. Documented Experiences and Best Practices
from various Industry Projects
English language:
Software & Systems
Requirements
Engineering: In Practice
2009
McGrawHill
German language:
Systematisches
Requirements
Engineering
Fourth edition, 2012
Dpunkt.verlag
Link to web site McGrawHill Link to web site Dpunkt
2012 Siemens Healthcare Diagnostics Inc. Page 37