Systems Engineering
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Bringing Systems Into Being
Text
Systems Engineering and Analysis, B.S. Blanchard
and W. J. Fabrycky, 3rd edition, Prentice-Hall, 1998.
Systems Engineering Challenge
To bring products and systems into being
that meet customer expectations cost
effectively.
Engineering For Product
Competitiveness
1) Improving methods for defining product and
system requirements, including
determination of performance, effectiveness,
and essential system characteristics.
2) Addressing the total system with all of its
elements from a life – cycle perspective.
Engineering For Product
Competitiveness
3) Considering the overall system hierarchy and
interactions between various levels in the
hierarchy.
4) Organizing and integrating the necessary
engineering and related disciplines into the
main systems engineering effort in a timely
concurrent manner.
Engineering For Product
Competitiveness
5) Establishing a disciplined approach with
appropriate review, evaluation, and feedback
provisions to insure orderly and efficient
progress from the initial identification of need
through phase out and disposal.
System Engineering - Definitions
An interdisciplinary approach encompassing the
entire technical effort to evolve and verify an
integrated and life-cycle balanced set of system,
people, product, and process solutions that
satisfy customer needs. Systems engineering
encompasses:
System Engineering - Definitions
a) the technical efforts related to the development,
manufacturing, verification, deployment,
operations, support, disposal of, and user training
for system products and processes;
b) the definition and management of the system
configuration;
c) the translation of the system definition into work
breakdown structures;
d) development of information for management
decision making.
Key Words
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Top-down
Lifecycle
Interdisciplinary
Definition of System Requirements
System Lifecycle Process
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Definition of Need
Conceptual Design
Preliminary Design
Detail Design and Development
Production/Acquisition
Utilization and Support
Phaseout and Disposal
System Lifecycle
N
E
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D
Conceptual
Design
Detail
Design
Production
ACQUISITION PHASE
Product Use, Phase Out, Disposal
UTILIZATION PHASE
Conceptual Design
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Finalized Need Statement
Feasibility Analysis
High Level Requirements Analysis
- Operational Requirements
- Maintenance and Support
- Technical Performance Measures
Functional Analysis and Allocation
Analysis, Synthesis and Evaluation
Preliminary Design
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System Functional Analysis
Preliminary Synthesis and Allocation of Design
Criteria
System Optimization
System Synthesis and Definition
Detail Design
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System/Product Design
Prototype Development
System Prototype Test and Evaluation
Production & Product Use
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System Assessment and Evaluation
Modifications
- Corrective Action
- Product Improvement
Utilization and Support
- Assessment, Analysis and Evaluation
- Modifications
Phase Out And Disposal
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Design for Disposability
Green Engineering
Other Process Models
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Waterfall Model
Spiral Model
V Model
Note: Most models must be tailored!
System Design Evaluation/Feedback
System Design Criteria
Requirements Analysis
• Feasibility Analysis
• Operational Requirements
• Maintenance and Support Concept
• Measures of Effectiveness
(Technical Performance Measures, TPM)
System Level
System Design Evaluation
Design Evaluation
• Identification of Design-Dependent
Parameters (DDP)
• Analysis and Trade-off Studies
• Synthesis and Evaluation
System Level
System Design Criteria
Requirements Analysis
• Functional Analysis and Allocation
• Measures of Effectiveness
(Technical Performance Measures, TPM)
Subsystem Level
System Design Evaluation
Design Evaluation
• Identification of DDP
• Analysis and Trade-off Studies
• Synthesis and Evaluation
Subsystem Level
Evaluation of Multiple Criteria
System Attributes
Technical Performance
Measures
Design Dependent
Parameters
Multiple Criteria
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System Attributes
- arise from/in need statement
Technical Performance Measures (TPM)
- must be specified in terms of some level of
importance, as determined by the customer and
the criticality of the functions to be performed
Design Dependent Parameters(DDP)
- tradeoffs must be made
Generating Alternatives
SYSTEM VALUE
First-Order
Consideration
ECONOMIC FACTORS
TECHNICAL FACTORS
Second-Order
REVENUES
LIFECYCLE
COST
SYSTEM EFFECTIVENESS
Considerations
(Adapted From: Blanchard and Fabrycky, “System Engineering and Analysis, Prentice Hall, 1998)
Generating Design Alternatives
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Need, Functions, and Systems Requirements
1
Design
Decision
Schema
Design
Team
2
Feasibility
Design
Synthesis
TopDown
Approach
Candidate Design
4
Design
DDPs
Evaluation
3
Estimation/
Prediction
DIPs
Preferred 5
Candidate Physical and Economical Databases
Existing Components,
Parts, and Subsystems
BottomUp
Approach
T
E
C
H
N
O
L
O
G
I
E
S
(Adapted From: Blanchard and Fabrycky, “System Engineering and Analysis, Prentice Hall, 1998)
R
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A
R
C
H
A
N
D
D
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V
E
L
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P
M
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N
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Implementing Systems
Engineering
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Applications for Systems Engineering
Management of Systems Engineering
Potential Benefits