Systems EngineeringBringing Systems Into Being

TextSystems Engineering and Analysis, B.S. Blanchard and W. J. Fabrycky, 3rd edition, Prentice-Hall, 1998.

Systems Engineering ChallengeTo bring products and systems into being that meet customer expectations cost effectively.

Engineering For Product Competitiveness1) 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 Competitiveness3) 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 Competitiveness5) 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 - DefinitionsAn 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 - Definitionsa) 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

Top-down Lifecycle Interdisciplinary Definition of System Requirements

System Lifecycle Process

Definition of Need Conceptual Design Preliminary Design Detail Design and Development Production/Acquisition Utilization and Support Phaseout and Disposal

System LifecycleN E E DConceptual Design Detail Design Production

ACQUISITION PHASE

Product Use, Phase Out, Disposal

UTILIZATION PHASE

Conceptual Design

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

System Functional Analysis Preliminary Synthesis and Allocation of Design Criteria System Optimization System Synthesis and Definition

Detail Design

System/Product Design Prototype Development System Prototype Test and Evaluation

Production & Product Use

System Assessment and Evaluation Modifications - Corrective Action - Product Improvement Utilization and Support - Assessment, Analysis and Evaluation - Modifications

Phase Out And Disposal

Design for Disposability Green Engineering

Other Process Models

Waterfall Model Spiral Model V Model

Note: Most models must be tailored!

System Design Evaluation/Feedback

System Design CriteriaRequirements Analysis Feasibility Analysis Operational Requirements Maintenance and Support Concept Measures of Effectiveness (Technical Performance Measures, TPM) System Level

System Design EvaluationDesign Evaluation Identification of Design-Dependent Parameters (DDP) Analysis and Trade-off Studies Synthesis and Evaluation System Level

System Design CriteriaRequirements Analysis Functional Analysis and Allocation Measures of Effectiveness (Technical Performance Measures, TPM) Subsystem Level

System Design EvaluationDesign Evaluation Identification of DDP Analysis and Trade-off Studies Synthesis and Evaluation Subsystem Level

Evaluation of Multiple CriteriaSystem Attributes

Technical Performance Measures

Design Dependent Parameters

Multiple Criteria

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 AlternativesSYSTEM VALUE FirstFirst-Order Consideration ECONOMIC FACTORS TECHNICAL FACTORS SecondSecond-Order SYSTEM EFFECTIVENESS Considerations

REVENUES

LIFECYCLE COST

(Adapted From: Blanchard and Fabrycky, System Engineering and Analysis, Prentice Hall, 1998)

Generating Design AlternativesC U S T O M E R0 Need, Functions, and Systems Requirements 1 Design Decision Schema Design Team 4 2Feasibility

Design Synthesis

TopTopDown Approach

Candidate Design

3 Design DDPs EvaluationDIPs

Estimation/ Prediction BottomBottomUp Approach

Preferred 5 Candidate Physical and Economical Databases Existing Components, Parts, and Subsystems

T E C H N O L O G I E S

R E S E A R C H A N D D E V E L O P M E N T

(Adapted From: Blanchard and Fabrycky, System Engineering and Analysis, Prentice Hall, 1998)

Implementing Systems Engineering

Applications for Systems Engineering Management of Systems Engineering Potential Benefits