This document provides an introduction to complex system engineering. It defines what a system is, discusses system engineering and the system engineering process. It covers topics such as requirements, design, architecture, integration, verification and validation. The goal of system engineering is to design the right system to satisfy customer needs using an interdisciplinary approach.

1. Introduction to Complex System Engineering 3 march 2009 Emmanuel FUCHS Slides available soon at www.elfuchs.fr

3. Content • Complex System Example • System Definition • System Engineering • Design The Right System • Process • Requirements • Design and Architecture • Functional and Physical Allocation • Integration • IVVQCA

4. Complex System Examples Information Systems

5. System Problems Examples

6. System Problems Examples

8. System definition (Eberhardt Rechtin 1926-2006) A system is a construct or collection of different elements that together produce results not obtainable by the elements alone. The elements, or parts, can include people, hardware, software, facilities, policies, and documents; that is, all things required to produce systems-level results. The results include system level qualities, properties, characteristics, functions, behavior and performance. The value added by the system as a whole, beyond that contributed independently by the parts, is primarily created by the relationship among the parts; that is, how they are interconnected.

9. Systemic The whole is greater than the sum of the parts; T he part is greater than a fraction of the whole. Aristotle

10. System: another definition A system is any set (group) of interdependent or temporally interacting parts . Parts are generally systems themselves and are composed of other parts, just as systems are generally parts of other systems.

11. System Definition Sub System Sub System Sub System System Users Mission Environment Stakeholders Border

12. System Meta Model From INCOSE

13. SE Bodies http://www.afis.fr/ Association Française d'Ingénierie Système http://www.incose.org/ International Council on Systems Engineering (INCOSE)

15. System Engineering Definition “ an interdisciplinary approach encompassing the entire technical effort to evolve and verify an integrated and balanced set of system, people, product, and process solutions that satisfy customer needs …..”

16. System Engineering (SE) SE focuses on defining customer needs and required functionality early in the development cycle, documenting requirements, then proceeding with design synthesis and system validation while considering the complete problem Systems engineers deal with abstract systems, and rely on other engineering disciplines to design and deliver the tangible products that are the realization of those systems. Systems engineering effort spans the whole system lifecycle .

17. Systemic Approach One + One > two Aristotle : The whole is more than the sum of its parts. Parts (Components) Connections

18. System Engineering Meta Model From INCOSE

19. System engineer/architect Works with system abstraction. It is impossible to master everything Requirements Management System Model

21. Design the right system As proposed by the project sponsor As proposed by the programmers As specified in the project request As designed by the project analyst As installed at the users’ site What the customer really want

23. Process Definition Set of interrelated of interacting activities which transforms inputs to outputs P Inputs Outputs

24. A Process

25. Process: V cycle

26. Sequential V cycle drawbacks Documentation And mock-up Phase

27. Sequential V cycle drawbacks Documentation And mock-up Phase

28. Iterative and Incremental Incremental Iterative

29. Barry W. Boehm

30. Iterative and Incremental The Systems Engineering Process is not sequential. It is parallel and iterative. The complex interrelationship between creating and improving models throughout the process of developing and selecting alternatives is a good example of the dynamic nature of the systems engineering process.

31. Process Standardization NASA DOD (US Departement Of Defense): Documentation Model IEEE ISO (International Organization for Standardization) IEC (International Electrotechnical Committee). ISO/IEC 15504 / SPICE (Software Process Improvement and Capability dEtermination) SEI (Software Engineering Institute)

32. Capability Maturity Model - Integration CMMI defines the essential elements of effective processes for engineering disciplines based on best industry experiences . CMMI models provide guidance when developing and evaluating processes. CMMI models are not actually processes or process descriptions.

33. CMMI Maturity Levels process uncontrolled poorly managed and reactive initial 1 process characterized by projects and often reactive managed 2 process characterized for the organization and is proactive defined 3 process measured and controlled quantitatively managed 4 focus on process improvement optimizing 5 Status Identified as Level

34. ITIL ITIL : Information Technology Infrastructure Library http:// www.itil-officialsite.com

35. Process Documentation and Review SSS: System/Segment Specification SSDD : System/Segment Design Document IRS : Interface Requirement Specification ICD : Interface Control Definition SRR : System Requirement Review SDR : System Design Review TRR : Test Readiness Review

37. Process Activities

38. What is a requirement ? A requirement is a condition to be satisfied in order to respond to: A contract A standard A specification Any other document and / or model imposed.

39. Requirements User’s Requirements Statements in natural language of the system services. Described by the user System Requirements Structured document setting out detailed description of system services. Part of the contract

40. User’s Requirements example A customer must be able to abort a transaction in progress by pressing the Cancel key instead of responding to a request from the machine. The washing machine will be used in the following countries: UK, USA, Europe, Eastern Europe

41. Process

42. System Requirements The System shall provide ........ The System shall be capable of ........ The System shall weigh ........ The Subsystem #1 shall provide ........ The Subsystem #2 shall interface with .....

43. Requirement Quality A good requirement states something that is necessary , verifiable , and attainable To be verifiable, the requirement must state something that can be verified by: analysis, inspection, test, or demonstration (AIDT)

44. Requirement analysis User Requirement Minimum levels of noise and vibration are desirable . System Requirement Requirement 03320: The noise generated shall not exceed 60 db

45. Requirement Types Functional requirements Functional requirements capture the intended behavior of the system. This behavior may be expressed as services, tasks or functions the system is required to perform Non-Functional requirements All others Constraints

46. DOORS

47. DOORS

48. DOORS

50. Process

51. System Architecture The System Architecture identifies all the products (including enabling products) that are necessary to support the system and, by implication, the processes necessary for development, production/construction, deployment, operations, support, disposal, training, and verification

52. Architecture Modeling System : Abstraction Functional model Dynamic model Semantic Model Object model Physical Model Interfaces Model Model Views

53. Architecture Meta Model From IEEE

54. Architecture and Components Assembly

55. Example of Architecture Views The Functional Architecture identifies and structures the allocated functional and performance requirements. The Physical Architecture depicts the system product by showing how it is broken down into subsystems and components

56. Functional VS physical Model How to fly ? Look at birds: Physical Model So I need: Legs, Eyes, Brain, and Wings. But I can not fly !!! Why ? I have to find the flight functional model !

57. Example Birds physical for flying Physical decomposition: physical components that birds used to fly: Legs, Eyes, Brain, and Wings. But can not be applied to system directly

58. Flying functional model Functional decomposition of flying function: Produce horizontal thrust, Produce vertical lift. Takeoff and land, Sense position and velocity, Navigate,

59. Allocations Represent general relationships that map one model element to another Different types of allocation are: Behavioral (i.e., function to component) Structural (i.e., logical to physical) Software to Hardware ….

60. Bird and Airplane Functional to Physical architecture mapping Wings Wings Produce vertical lift Wings Propeller or jet Produce horizontal thrust Brain Brain or computer Navigate Eyes Vision or radar Sense position and velocity Legs Wheels, Takeoff and land Bird Physical Component Airplane Physical Component Function

61. Stove Pipe architecture User Functional Organization Physical

62. Multi-criteria decision

63. Trade Off Multi-criteria decision-aiding techniques are available to help discover the preferred alternatives. This analysis should be repeated, as better data becomes available.

65. Tower Crane example

66. Tower Crane example x

67. French Tower Cranes

68. British Tower Cranes

69. British Tower Cranes

70. British Tower Cranes

71. British Tower Cranes

72. Luffing jib tower crane When the jib is moved, the hoist gear is controlled in such a way as to ensure that the hook travels horizontally.

73. Luffing jib tower crane

74. The two types of basic jib design Horizontal Jib This jib takes the form of a simple structure extending from the tower, along which a trolley can travel, carrying the hoist rope and hook assembly to vary radii. Luffing Jib The luffing jib has no trolley, the variation of hook radii is achieved by altering the jib angle, the same as with a mobile crane.

75. Horizontal Jib

76. Luffing Jib

77. Luffing jib tower crane These cranes have been designed for work on particularly high buildings or in extremely restricted spaces. These cranes can solve all the problems that may appear in building sites settled in crowded places, in the town centres or in some areas full of obstacles like prefabricated buildings or towers.

78. Washing Machine example

79. Functional To Physical Model Functional : Discover the system functions Washing Machine What it does ? Washes How it does ? Agitates Physical Component : Agitator

80. Washing Machine Physical Model agitator tube draining hand-operated washer plungers

81. Washing Machine Physical Model agitator Outer tube draining top loading US

82. Washing Machine Physical Model agitator Outer tube draining Inner tube = drum front loading Europe

83. Washing Machine Functional model

84. Context Diagram

85. Washing Machine Functional Breakdown

86. Washing Machine Data Flows

87. Washing Machine allocation example

88. Washing Machine Physical Model agitator tube draining hand-operated washer plungers

89. Washing Machine Physical Model agitator Outer tube draining top loading US

90. Washing Machine Physical Model agitator Outer tube draining Inner tube = drum front loading Europe

91. Washing Machine Physical Model top loading

92. Washing Machine Physical Model front loading

93. Washing Machine Physical Model front loading

94. UML

95. SysML

96. Block definition diagram of the Clothe Washing Domain

97. Activity hierarchy in block diagram definition (Hierarchical Functional Model)

98. Washing Machine Data Flows

100. Process

101. Process: V cycle

102. Integration Integration means bringing things together so they work as a whole.

103. Spaghetti Plate Syndrome Spaghetti Plate System Architect System Integrator

104. Encapsulation A nalogy Implementation Interface A driver doesn't care of engine's internal working. He only knows the interface

106. Process

107. IVVQCA Integrate : Build the system Verification : Ensures that you built it right Validation : Ensures that you built the right thing Certification : Ensure that the system is safe Acceptance : Ensures that the customer gets what he wants and the company get paid.

108. Ensure that the system is safe

109. Conclusion Thank You For Your Attention Questions are welcome Contacts : [email_address] Slides Available soon at www.elfuchs.fr