In the name of ALLAH The Most Beneficent The Most Merciful

1. In the name of ALLAHThe Most BeneficentThe Most Merciful

2. Multidisciplinary Engineering Design Optimization (MCE 540 Graduate Course – Mechanical Engineering Department) • Instructor: • Assist. Prof. Dr.-Ing. Mostafa Ranjbar • Ph.D. (Dr-Ing.), Multidisciplinary Engineering Design Optimization of Structures,TechnischeUniversität Dresden, Germany, 2011 • M.Sc., Vibration Monitoring and Fault Diagnosis of Structures, TarbiatModares University, Tehran, Iran, 2000 • B.Sc., Mechanical Engineering, Shiraz university, Iran, 1998

3. MULTIDISCIPLINARY SYSTEM DESIGNOptimization LECTURE # 2

4. Msdo_______________TerminologYand Problem Statement LECTURE # 2

5. INTRODUCTION • PHASE-I • Introduction to Multidisciplinary System Design Optimization • Terminology and Problem Statement • Introduction to Optimization • Classification of Optimization Problems • Numerical Optimization • MSDO Architectures • Practical Applications

6. LECTURE OUTLINE • Course Introduction • Introduction to (Multidisciplinary) (System) Design Optimization • Systems • Evolution of Design Process • Optimization

7. MSDO: Overview OVERVIEW • Multidisciplinary System Design Optimization (MSDO) deals with the optimization of several engineering disciplines simultaneously. • MSDO gives the engineer the opportunity to find the optimal solution of some system accounting for the interactions between the different disciplines. • It should be noted that the multidisciplinary solution might not be the solution for any one discipline analyzed separate from the other disciplines, but is the best solution accounting for the interactions. • The MSDO field has become vital in design environments in the past decades as systems are becoming more and more complex.

8. WHY MSDO??? OVERVIEW • To enable the design of high performance products, • Balance product performance considerations with manufacturing, economics, and life cycle issues, • Achieve design process timetable compression • Economic competitiveness • Respect the problem physics of coupled systems • towards a physically meaningful design practice.

9. TERMINOLOGYandProblem Statement

10. TERMINOLOGY

11. MSDO TERMINOLOGY • Multidisciplinary System Design Optimization • Multidisciplinary ? • System ? • Design ? • Optimization ?

12. SYSTEM

13. MSDO: Terminology What is a SYSTEM? • A system can be thought of as a set of elements that interact with one another in an organized or interrelated fashion toward a common purpose that cannot be achieved by any of the elements alone or by all of the elements without the underlying organization.

14. MSDO: Terminology What is a SYSTEM? • The personal computer (PC) shown in Figure is an example of a system. The elements of the PC include the processor, display, software, and keyboard. The soldering iron is symbolic of the manufacturing, test, and maintenance equipment that are also system elements. The elements are organized or interrelated to achieve the purpose of the PC. The organization is facilitated by electrical cables and connectors and mechanical fasteners. The elements of the processor consist of the motherboard, the power supply, the case etc., all organized to carry out the processing. The motherboard is further made up of parts and materials that have been assembled via processes such as soldering. • Parts, materials, and processes are the building blocks of most man-made systems.

15. MSDO: Terminology SYSTEM • A system is a physical or virtual object that exhibits some behavior or performs some function as a consequence of interactions between the constituent elements.

16. MSDO: Terminology SYSTEM

17. MSDO: Terminology SYSTEM • 1. The organization of hardware, software, materials, facilities, personnel, data, and services needed to perform a designated function with specified results, such as the gathering of specified data, its processing, and delivery to users. • 2. A combination of two or more interrelated equipment (sets) arranged in a functional package to perform an operational function or to satisfy a requirement.

18. MSDO: Terminology SYSTEM • A system is a physical or virtual object that exhibits some behavior or performs some function as a consequence of interactions between the constituent elements.

19. MSDO: Terminology SYSTEM

20. MSDO: Terminology SYSTEM

21. MSDO: Terminology SYSTEM

22. MSDO: Terminology SYSTEM

23. MSDO: Terminology SYSTEM

24. MSDO: Terminology SYSTEM

25. MSDO: Terminology SYSTEM

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27. MSDO: Terminology SYSTEM

28. MSDO: Terminology SYSTEM

29. MSDO: Terminology SYSTEM • A system is a physical or virtual object that is composed of more than one element and that exhibits some behavior or performs some function as a consequence of interactions between these constituent elements. • FAMILY of SYSTEMS: A set or arrangement of independent systems that can be arranged or interconnected in various ways to provide different capabilities. The mix of systems can be tailored to provide desired capabilities dependent on the situation

30. MSDO: Terminology SYSTEM • A system can be compartmentalized into parts. Usually this follows a hierarchy of compartmentalization into smaller and smaller parts. Generically, the system is compartmentalized into subsystems; the subsystems are compartmentalized into sub-subsystems, etc. Sometimes the various levels of the hierarchy are given specific names, such as in the following examples which are not unique: Level Specific Name • System Launch vehicle • Subsystem Propulsion • Element SRM • Component Ignition Device • Part Igniter

31. MSDO: Terminology COMPARTMENTALIZATION • Separation of the design process into manageable parts. • There are three types of compartmentalization: • Separation of a system into subsystems (subsystems can be further compartmentalized into sub-subsystems); • Separation of the design functions for each subsystem; • Separation of the design functions into the discipline activities necessary to achieve the design.

32. MSDO: Terminology

33. MSDO: Terminology SYSTEM ARCHITECTURE • A System Architecture is defined as the structure, arrangement, or configuration of a system of elements and the relationships required to satisfy both the constraints and a set of functional, performance, reliability, maintainability, and extensibility requirements [Boppe, 1997]. • The structure and relationship among the components of a system. The system architecture may also include the system’s interface with its operational environment. A framework or structure that portrays relationships among all the elements of systems. • SYSTEM ARCHITECTURE is an abstract description of the entities of a system and the relationships between those entities. Architecture is important in most technical fields, including not only civil architecture of buildings but of physical products, software, computer networks, large engineering systems, and infrastructures. The architecture of a system has a strong influence on its behavior. Every system has an architecture.

34. MSDO: Terminology SYSTEM ARCHITECTURE • A set or arrangement of interdependent systems designed to be interconnected in various ways to provide capabilities beyond those systems operating autonomously. • Each component system is designed with a “fall back” capability to operate autonomously, but when operated as an interconnected set, their capabilities are enhanced. • The degree of interdependence can vary from loosely coupled (federated) to tightly coupled (integrated), but the capability of the set is always greater than the sum of the elements operated autonomously.

35. MSDO: Terminology SYSTEM CONSTANTS • These are quantities fixed by the underlying phenomenon rather than by the particular model statement. • Typically, they are natural constants, for example, a gas constant, and the designer has no influence upon them

36. MSDO: Terminology SYSTEM PARAMETERS • These are quantities that are given one specific value in any particular model statement. They are fixed by the application of the mode, rather than by the underlying phenomenon. Examples are atmospheric pressure and required power. • System requirements review (SRR). Demonstrates that the mission and system requirements are defined and understood. In addition, management techniques, procedures, agreements, etc., are evaluated. • System variables: These are quantities that specify different states of a system by assuming different values (possibly within acceptable ranges). Examples are the size of an engine.

37. The systems approach to problem solving – so simple but so complicated

38. MODEL

39. MSDO: Terminology MODEL • A model is an abstraction of a real world construct [Shishko & Chamberlain, 1995]. • A model is a Mathematical Object that has the ability to predict the behavior of a real system under a set of defined operating conditions and simplifying assumptions

40. MSDO: Terminology MODEL • In forming a model for use with optimization, all of the important aspects of the problem should be included, so that they will be taken into account in the solution. • The model can improve visualization of many interconnected aspects of the problem that cannot be grasped on the basis of the individual parts alone.

41. MSDO: Terminology MATHEMATICAL MODEL • A mathematical model of the process or system is then formed on the basis of this description. Depending on the application, the model complexity can range from very simple to extremely complex. • An example of a simple model is one that depends on only a single nonlinear algebraic function of one variable to be selected by the optimizer (the decision maker). • Complex models may contain thousands of linear and nonlinear functions of many variables.

42. MSDO: Terminology TYPES of MODELS • There are a number of ways mathematical models can be usefully categorized. One way is according to its purpose in the trade study process—that is, what system issue and what level of detail the model addresses, and with which outcome variable or variables the model primarily deals. • Other commonly used ways of categorizing mathematical models focus on specific model attributes such as whether a model is: • Static or dynamic • Deterministic or probabilistic (also called stochastic) • Descriptive or optimizing.

43. MSDO: Terminology TYPES of MODELS • These terms allow model builders and model users to enter into a dialogue with each other about the type of model used in a particular analysis or trade study. • No hierarchy is implied in the above list; none of the above dichotomous categorizations stands above the others. • Mathematical simulations are a particularly useful type of model in trade studies.

44. MSDO: Terminology TYPES of MODELS • These kinds of models have been successfully used in dealing quantitatively with large complex systems problems in manufacturing, transportation, and logistics. • Simulation models are used for these problems because it is not possible to "solve" the system's equations analytically to obtain a closed-form solution, yet it is relatively easy to obtain the desired results (usually the system's behavior under different assumptions) using the sheer computational power of current computers.

45. MSDO: Terminology TYPES of MODELS • Linear, nonlinear, integer and dynamic programming models are another important class of models in trade studies because they can optimize an objective function representing an important outcome variable (for example, system effectiveness) for a whole class of implied alternatives. • Their power is best applied in situations where the system's objective function and constraints are well understood, and these constraints can be written as a set of equalities and inequalities

46. MSDO: Terminology SIMULATION • Simulation is the process of exercising a model for a particular instantiation of the system and specific set of inputs in order to predict the system’s response.

47. MSDO: Terminology MODELLING & SIMULATION • Models play important and diverse roles in systems engineering. A model can be defined in several ways, including: • An abstraction of reality designed to answer specific questions about the real world • An imitation, analogue, or representation of a real world process or structure; or • A conceptual, mathematical, or physical tool to assist a decision maker. • Together, these definitions are broad enough to encompass physical engineering models used in the verification of a system design, as well as schematic models like a functional flow block diagram and mathematical (i.e., quantitative) models used in the trade study process.

48. MSDO: Terminology MODELLING & SIMULATION • The main reason for using mathematical models in trade studies is to provide estimates of system effectiveness, performance or technical attributes, and cost from a set of known or estimable quantities. • Typically, a collection of separate models is needed to provide all of these outcome variables. • The heart of any mathematical model is a set of meaningful quantitative relationships among its inputs and outputs. • These relationships can be as simple as adding up constituent quantities to obtain a total, or as complex as a set of differential equations describing the trajectory of a missile in a gravitational field.

49. MSDO: Model Development

50. SYSTEMS ENGINEERING