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1 | 2010
Lecture 1: Systems – what and why?
Covered in this lecture• Systems and systems thinking• Why we use Systems Engineering• Systems from “cradle to grave”
2 | 2010
Systems and systems thinking
3 | 2010
Definition of a System
• “a combination of interacting elements organized to achieve one or more stated purpose”
• “an integrated set of elements, subsystems, or assemblies that accomplish a defined objective. These elements include products (hardware, software, firmware), processes, people, information, techniques, facilities, services, and other support elements.
4 | 2010
From: INCOSE
The elements of a system• Systems are composed of components, attributes, and relationships. These are described as follows:
• Components are the parts of a system• Attributes are the properties (characteristics, configuration, qualities, powers, constraints and states)• Relationships between pairs of linked components are the result of engineering the attributes of both components so that the pairs operates together effectively in contributing to the system’s
purpose(s)
5 | 2010
Which of these are systems? What are their purpose; the main components; attributes and relationships?
6 | 2010
Systems of Systems (SoS)• SoS are systems-of-interest whose system elements are themselves system.
• SoS are defined as an interoperating collection of component systems that produce results unachievable by the individual systems alone.
Example: Transport System-of-Systems
Systems of Systems• Challenges with development of SoS:
• System elements operate independently• System elements have different life cycles• The initial requirements are likely to be ambiguous• Complexity is a major issue• Management can overshadow engineering• Fuzzy boundaries cause confusion• SoS engineering is never finished
The hierarchy within a system
10 | 2010
Example: Space Transportation System
11 | 2010
From: NASA Systems Engineering Handbook
Example: Space Transportation System
12 | 2010
From: NASA Systems Engineering Handbook
Example: Space Transportation System
13 | 2010
From: NASA Systems Engineering Handbook
Why we use Systems Engineering
14 | 2010
Systems engineering emerged as an effective way to manage complexity and change. Reducing the risk associated with new systems or
modifications to complex systems continues to be primary goal of the systems engineer.
Use of Systems Engineering 100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
ConceptDesign
Develop
Prod/Test
OperationsThroughDisposal
8% 15% 20%
100%
Committed Costs
70%
85%95%
3-6X
20-100X
500-1000X
Time
50%
Cu
mu
lati
ve P
erc
en
tag
e L
ife C
ycle
Co
st
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
ConceptDesign
Develop
Prod/Test
OperationsThroughDisposal
8% 15% 20%
100%
Committed Costs
70%
85%95%
3-6X
20-100X
500-1000X
Time
50%
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
ConceptDesign
Develop
Prod/Test
OperationsThroughDisposal
8% 15% 20%
100%
Committed Costs
70%
85%95%
3-6X
20-100X
500-1000X
Time
50%
Cu
mu
lati
ve P
erc
en
tag
e L
ife C
ycle
Co
st
Committed Life Cycle Cost against Time
From prototype to market penetration
Pe
ne
tra
tio
n in
toth
em
ark
et
(%)
0 10 20 30 40 50 60 70 80 90 100 110 120 years
Videorecorder(1952)
Mobile Phone(1983)
Internet(1975)
Personal Computer
(1975)
Microwave(1953)
Radio(1905)
TV(1926)
Electricity(1873) Phone
(1876)
Car(1886)
Source: Microsoft
100
90
80
70
60
50
40
30
20
10
0
Cost and schedule overruns lessens with increasing systems engineering effort
Variance in the cost and schedule overruns also lessens with increasing systems engineering
effort
Value of Systems Engineering
Cost and schedule overruns correlated with systems engineering effort
Systems from cradle to grave
Life-cycle model
18 | 2010
Generic Business life-cycle
• Every system or product life cycle consists of the business aspect (business case), the budget aspect (funding) and the technical aspect (product)
• The systems engineer creates technical solutions that are consistent with the business case and the funding constraints
InvestmentsRevenues
Order intake
Business Development, Marketg
System Engineering
Design
Production
Operation
Accumulated $,€
Break even -RETURN ON INVESTMENT !
years- 10 - 5 5 10 15 20
Life-cycle stages
Decision Gates• Decision Gates (control gates, milestones, reviews) represent major decision points in the system life cycle
• Objectives:• Ensure business and technical baselines are acceptable and will lead to satisfactory verification and validation• Ensure that the risk of proceeding to the next step is acceptable• Continue to foster buyer and seller teamwork
22 | 2010
From: NASA Systems Engineering Handbook
23 | 2010
From: NASA Systems Engineering Handbook
”Vee”-model
24 | 2010
From: Forsberg, System Engineering for faster, cheaper, better
Left side of the Vee model
Right side of the Vee model