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Massachusetts Institute of Technology © Ed Crawley 2002 1 From Value to Architecture Ed Crawley Aeronautics and Astronautics Engineering Systems MIT.

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Presentation on theme: "Massachusetts Institute of Technology © Ed Crawley 2002 1 From Value to Architecture Ed Crawley Aeronautics and Astronautics Engineering Systems MIT."— Presentation transcript:

1 Massachusetts Institute of Technology © Ed Crawley From Value to Architecture Ed Crawley Aeronautics and Astronautics Engineering Systems MIT

2 Massachusetts Institute of Technology © Ed Crawley Today’s Topics Objectives Analysis of architecture A useful tool Synthesis of architecture

3 Massachusetts Institute of Technology © Ed Crawley Learning Objectives 0) Be able to apply the principles, processes and tools of system architecting to structure and lead the early, conceptual PDP phase 1) Discuss systems, systems thinking, products, the PDP and the role of the architect 2) Critique and create architecture, and deliver the deliverables 3) Drive ambiguity out of the upstream process 4) Create the concept 5) Manage the evolution of complexity 6) Critically evaluate current modes of architecture 7) Develop the principles of architecting This is a course in how to think, not what to think

4 Massachusetts Institute of Technology © Ed Crawley Process for Critical Thinking Opportunity, challenge, or reference example identified Thinker develops an approach option Thinker identifies other options, then analyzes and criticizes the options vs. each other and the “developed” approach Synthesized, context-appropriate “best” option is defined

5 Massachusetts Institute of Technology © Ed Crawley The Role of the Architect Defines the boundaries, goals, and functions Creates the Concept Allocates functionality and defines interfaces and abstractions The architect is not a generalist, but a specialist in simplifying complexity, resolving ambiguity and focusing creativity

6 Massachusetts Institute of Technology © Ed Crawley Four Basic Tensions in Product/System Development Benefit ScheduleRisk Cost Value is Benefit at Cost

7 Massachusetts Institute of Technology © Ed Crawley The Architect Creates Good Architecture Satisfies customer needs Incorporates appropriate technology Meets strategic business goals Meets or exceeds present and future regulations HIs operable, maintainable, sustainable, reliable HCan be evolved/modified as appropriate Can be designed and implemented by envisioned team Can be implemented with existing/planned capabilities AND IS ELEGANT

8 Massachusetts Institute of Technology © Ed Crawley Deliverables of the Architect A clear, complete, consistent and attainable (with 80%- 90%confidence) set of goals (with emphasis on functional goals) A functional description of the system, with at least two layers of decomposition A concept for the system A design for the form of the system, with at least two layers of decomposition A notion of the timing, operator attributes, and the implementation and operation plans A document or process which ensures functional decomposition is followed, and the form at interfaces is controlled

9 Massachusetts Institute of Technology © Ed Crawley Architecture - 6 Views Principles Methods & Tools ThemesCasesFrameworks Roles & Definitions

10 Massachusetts Institute of Technology © Ed Crawley Analysis of Architecture Form, function and concept - the architecture Upstream influences Downstream influences

11 Massachusetts Institute of Technology © Ed Crawley A Definition Architecture – The embodiment of concept, and the allocation of physical/informational function (process) to elements of form (objects) and definition of structural interfaces among the objects Consists of: – Function – Related by Concept – To Form Form Function Concept

12 Massachusetts Institute of Technology © Ed Crawley Architecture – Form Suspension bridge Cable-stayed bridge

13 Massachusetts Institute of Technology © Ed Crawley Product Attribute - Function Function is the activity, operations, transformations that create or contribute to performance Function is a system attribute, created by the architect Function is associated with form, and emerges as form is assembled Function can stated in solution neutral form, as a verb plus noun, and with a limited syntax Externally delivered function is linked to value of a product

14 Massachusetts Institute of Technology © Ed Crawley Function is Associate with Form Change voltage proportional to current Change voltage proportional to charge React translation forces Carry moment and shear

15 Massachusetts Institute of Technology © Ed Crawley Concept - the Mapping of Form to Function A system vision which maps form to function and embodies working principles Is in solution-specific vocabulary - it is the solution Is created by the architect Must allow for the execution of all functions Specifies the vector of design parameters, which, when selected, will establish the design Is an abstraction of form, or form is a specification of concept Form Function Concept

16 Massachusetts Institute of Technology © Ed Crawley Dominant Upstream Influence on Architecture Regulation Corporate, Marketing Strategy Customers Competitive Environment Technology Architecture NeedGoals Downstream Strategies, Competence Form Function Concept

17 Massachusetts Institute of Technology © Ed Crawley Product Attribute - Need Need is defined as: – an overall desire or want – a necessity – a wish for something which is lacking Can also include opportunities to fill unexpressed needs Exists in the mind of the beneficiary (outside the enterprise) Expressed often in fuzzy or general (i.e. ambiguous) terms Is interpreted (in part) by the architect

18 Massachusetts Institute of Technology © Ed Crawley Product Attribute - Goals Goal is defined as – what it accomplishes, its performance – what the designer hopes to achieve or obtain Expressed in the precise terms of Product Development Will include goals derived from user Needs (goals from beneficiaries) i.e. the external functional goals Will also include goals from corporate strategy, regulations, competitive analysis, etc. Embodied in a statement of goals (requirements ?) Is defined (in part) by the architect Exist within, and under the control of the enterprise, and are traded against other attributes

19 Massachusetts Institute of Technology © Ed Crawley Framework for Downstream Influences Implementation Evolution Operations Architecture Design Operational sequence and dynamic behavior Operator (training, etc.) Operational cost Form Function Concept

20 Massachusetts Institute of Technology © Ed Crawley Product Attribute - Timing When the system operates, the time sequence of events Has two important aspects – Operational sequence – Dynamic behavior Operations sequence is the total set of steps or processes that the system undergoes, inclusive of the primary process for which it is intended – Including set up, take down, stand alone, contingency and emergency operations Dynamic behavior is the detailed timing of steps, their sequence, start time, duration, overlap, etc.

21 Massachusetts Institute of Technology © Ed Crawley Overall Operational Sequence Waiting in storage Retrieving, connecting, powering-up, setting up, initializing Loading, preparing Process only ops. Contingency ops. Emergency ops. Archiving, unloading Terminating, disconnecting, depowering, storing Inspecting, repairing, calibrating, updating, maintaining Executing Primary Process OPERATING Store Get ready Get set Go Get unset Get unready Fix

22 Massachusetts Institute of Technology © Ed Crawley Product Attribute - Operator Who will use/execute the system Necessary for products with human agents/operators/supervisors [which ones don’t?] – most important for human-in-loop (e.g. aircraft, bicycle) – important for direct human operation (e.g. lathe, wheelchair, calculator) – for other products, can be considered part of interface/constraints (e.g. human factors design, industrial design) Because of the unique issues of human performance and safety, it is useful to keep separate as an additional attribute

23 Massachusetts Institute of Technology © Ed Crawley Product Attribute - Operations Cost Operations Cost is a product attribute How much it will cost to operate the system This is the recurring operational related costs – Operator and other personnel – Training – Maintenance and (nominal) upgrades – Consumables – Indirect operating costs (insurance, etc.)

24 Massachusetts Institute of Technology © Ed Crawley Holistic Framework for Attributes of the Product and its Operations global why the system is built need opportunity global what the system accomplishes goals performance global how the system acts function process global where the elements are form structure global when things occur timing dynamics global who does them operator user global how much does it cost cost expense

25 Massachusetts Institute of Technology © Ed Crawley Other Downstream Processes The system must be designed, so it must be architected in such a way that design can proceed smoothly and efficiently The system must be implemented, so it must be architected for manufacturability, coding, integration, test, and verification The system may evolve and be updated, so it must be architected with a view towards these changes - Evolution is really just a recursive pass through conception, design and implementation Each has its own who, what, where, when,...

26 Massachusetts Institute of Technology © Ed Crawley Qualitative PDP - CDIO Impl. Schedule Impl. Team Impl. Tools Process Flow Impl. Goals Customer Corporate Societal Needs Design Schedule Process Methods Design Goals NRE Costs Product Operator Product Goal Operating Costs Impl. Costs Product Form Product Function Design Tools Design Team Product Timing Conceiving Designing Operating Implementing

27 Massachusetts Institute of Technology © Ed Crawley Business Strategy Functional Strategy Customer Needs Competitors Program plan Business case Generic PDP Conceive MissionConceptual Design Goals Function Concepts Regulation Technology Platform plan Supplier plan Architecture Commitment Requirements definition Model development Requirements flowdown Detail decomposition Interface control Design Preliminary Design Detailed Design Design elaboration Goal verification Failure & contingency analysis Validated design Implement Element Creation Integration, System Test Operate Life Cycle Support Evolution Sourcing Implementation ramp-up Element implementation Element testing Element refinement Product integration Product testing System testing Refinement Certification Market positioning Delivery Sales, Distribution Operations Logistics Customer support Maintenance, repair, overhaul Upgrades Product improve- ment Family expansion Retirement Envision Design Develop Deploy

28 Massachusetts Institute of Technology © Ed Crawley A Tool - Object Process Modeling Object: that which has the potential of stable, unconditional existence for some positive duration of time. Objects have states. Form is the sum of objects Process: the pattern of transformation applied to one or more objects. Processes change states. Function emerges from processes All links between objects and processes have precise semantics Objects Processes

29 Massachusetts Institute of Technology © Ed Crawley Process and its Links A process is associated with a verb and stateless There are a family of about 5 types of links from process to object A process changes the states of its operand(s) through input and output links Transporting changes person from here to there. Input link Output link

30 Massachusetts Institute of Technology © Ed Crawley Summary Object-Process Links P affects O (affectee) P yields O (Resultee) P consumes O (Consumee) P changes O (from state A to B). P is handled by O (agent) P requires O (Instrument)

31 Massachusetts Institute of Technology © Ed Crawley Emergence A process can be zoomed into sub-processes A process emerges from sub-processes The process and sub-processes are not linked in any explicit manner, as the object decomposes into parts Emergence is a powerful feature of systems - parts and sub-processes can come together to cause a process to emerge Emergence sometimes yields the anticipated processes, sometimes does not yield the anticipated process and sometimes unanticipated processes

32 Massachusetts Institute of Technology © Ed Crawley Synthesis of Products Parallel processes: Architecture & Business Case Tracing value to architecture Ambiguity, creativity and complexity Conclusions

33 Massachusetts Institute of Technology © Ed Crawley Parallel Cycles The parallel cycles end when: - The technical architecture “closes” - The business case “closes” The outputs are products with value to customer and profits with value to share holder, while providing appropriate value to society and workforce.

34 Massachusetts Institute of Technology © Ed Crawley Intent An Intent is – What the purpose is – What someone hopes to achieve or obtain Is always defined by someone Useful to create a special symbol for this information object - supposed to remind you of an arrow - where you are going Intent

35 Massachusetts Institute of Technology © Ed Crawley Function - A Formal Definition Previous Definition: the …transformation…that contribute to performance…the actions…for which a thing exists Function is intent plus process Intent Process

36 Massachusetts Institute of Technology © Ed Crawley Value - Formal Definitions Value is delivered when the primary external process(es) acts on the operand in such a way that the needs of the beneficiary are satisfied at a desirable cost. Delivering Primary Process Operand Intent on process Has Beneficiary Needs Product Object Interpreting & Incorporating Value Delivery Value Identification Value: “how various stakeholders find particular worth, utility, benefit, or reward in exchange for their respective contributions to the enterprise” Murman, et al. LEV p178 Value Proposition

37 Massachusetts Institute of Technology © Ed Crawley Product Systems and Value Products include Goods, which are objects which implicitly execute a process Products include Services, which are processes enabled by implicit objects In both cases, the value to the primary beneficiary is in the process, not the object Products Services Implicit Process Goods Implicit Objects

38 Massachusetts Institute of Technology © Ed Crawley Whole Product System The whole system is the array of objects necessary to deliver the externally delivered process to the operand(s).

39 Massachusetts Institute of Technology © Ed Crawley Value to Intent Start by examining the operand associated with value Next identify the attribute of the operand whose change is associated with value Next define the transformation of the attribute associated with value, in solution neutral form This will reduce ambiguity and lead you to a value focused, solution neutral statement of intent on process

40 Massachusetts Institute of Technology © Ed Crawley Concept Concept: a system vision, which embodies working principles, a mapping from function to form Choose from among the system operating processing that specialize to the desired solution neutral, value related process Specialize the related generic concept to the product form This is the exercise of creativity Concept Five primary functions. McGee, deWeck

41 Massachusetts Institute of Technology © Ed Crawley Capturing Intent Once the system is modeled or built, the “attribute transforming” process and “concept” object vanish The “attribute transforming” can be captured as an intent object The concept usually remains implicit, represented by the operating process and concept specialization

42 Massachusetts Institute of Technology © Ed Crawley Decomposition of Function and Form Identify form of the whole product system Zoom the processes of function Decompose the form of the product object Establish the object process links

43 Massachusetts Institute of Technology © Ed Crawley Form and Function - Cooler The whole product includes the ice, food, supporting surface, heat load, light and operator Chilling zooms to the stated processes (using process precedence framework) Cooler decomposes to box and top Map objects to processes to determine object- process architecture Establishing the complexity of the object-process architecture

44 Massachusetts Institute of Technology © Ed Crawley Structure of Form - Cooler Examine the interactions implied by the decompositio n of form Establishing the complexity of the object-object architecture

45 Massachusetts Institute of Technology © Ed Crawley Form and Function - Refrigerator More one to one correspondence of objects and processes Note the whole product elements suppressed: – Food – Support structure – Heat load – Operator

46 Massachusetts Institute of Technology © Ed Crawley Structure of Form - Refrigerator Considerably more object - object complexity

47 Massachusetts Institute of Technology © Ed Crawley So Why Refrigerators and not Coolers? Refrigerators have significantly more complexity than coolers Refrigerators have more functions, performance and robustness than coolers. Principle: underlying and long enduring fundamentals that are always (or almost always) valid. Is a principle lurking here?

48 Massachusetts Institute of Technology © Ed Crawley 2002 Robust Functionality Drives Essential Complexity Essential complexity is that which is essential to deliver functionality before gratuitous complexity slips in Functionality drives complexity in any given concept But “Functionality” is often defined as a surrogate for a much broader set of functions which the product will actually be use for. Therefore, it is the (often implicit) robust functionality which drives essential complexity A Principle

49 Massachusetts Institute of Technology © Ed Crawley Conclusions Architecture requires consideration of form and function, related through concept Value derives from function Starting with the operand, its transformation identifies concepts which deliver value Concepts elaborate into architectures which have form-function and structural complexity Essential complexity is accepted to deliver robust functionality


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