Engineering and Science

Engineering Engineering and Scienceand Science

Purpose and NaturePurpose and Nature

Science is the search for Science is the search for knowledge and understandingknowledge and understanding

Technology is the application of Technology is the application of knowledge to satisfy human knowledge to satisfy human needsneeds

They are both creative problem They are both creative problem solving methods!solving methods!

Engineering is...Engineering is...

“… the profession in which a knowledge of mathematics and natural sciences gained by study, experience, and practice is applied with judgment to develop ways to utilize, economically, the materials and forces of nature for the benefit of mankind." (ABET)

Processes ComparedProcesses Compared

Scientific Method

Engineering Design

Process

Why? Knowledge

Need Thing

Specification

The Rest of EngineeringThe Rest of Engineering

Engineers Drive Trains!Engineers Drive Trains!

The distinctions among science and The distinctions among science and engineering and technology are often arbitraryengineering and technology are often arbitraryEngineering design, product testing, Engineering design, product testing, engineering analysis, scientific method are engineering analysis, scientific method are allall creative, problem solving processescreative, problem solving processesHowever, schools teach Engineering using the However, schools teach Engineering using the scientific process with very little hands-on or scientific process with very little hands-on or applied learning activitiesapplied learning activitiesStudents are often left wondering what Students are often left wondering what Engineers really do Engineers really do

Engineering Engineering Design Design

Process Process DescriptionDescription

Engineering Design DefinedEngineering Design Defined

The crux of the design The crux of the design process is creating a process is creating a satisfactory solution to a satisfactory solution to a need need HarrisbergerHarrisberger

The Engineering Design The Engineering Design Process?Process?

Customer Needor Opportunity

Implementation ofOptimal Design

Evaluation of Designs/Selection of Optimal Design

Development ofAlternative Designs

Data & InformationCollection

Problem Definition/Specifications

Source: Accrediting Board For Engineering and Technology

Engineering DesignEngineering Design

Define a needDefine a need

Develop design criteriaDevelop design criteria

Search literature to see what has been Search literature to see what has been donedone

Prepare preliminary designsPrepare preliminary designs

Build and test a prototypeBuild and test a prototype

Redesign and retest as necessaryRedesign and retest as necessary

Source: http://www.sciserv.org/isef/document/index

Dissecting the Dissecting the Engineering Engineering

Design ProcessDesign Process

NeedNeed

Have a need, have a customerHave a need, have a customer

External vs internal; Implied vs explicitExternal vs internal; Implied vs explicit

Often stated as functional requirement Often stated as functional requirement

Often stated as bigger, cheaper, faster, lighterOften stated as bigger, cheaper, faster, lighter

Boilerplate purpose: Boilerplate purpose: The design and The design and construction of aconstruction of a (better____something)_____ (better____something)_____ forfor (kids, manufacturing, medicine) (kids, manufacturing, medicine) to do to do __________.__________.

Criteria & ConstraintsCriteria & Constraints“Design criteria are requirements you specify for your design that will be used to make decisions about how to build the product”

Aesthetics

Geometry

Physical Features

Performance

Inputs-Outputs

Use Environment

Usability

Reliability

Some Design ConstraintsSome Design Constraints

CostCost

TimeTime

KnowledgeKnowledge

Legal, ethical Legal, ethical

Physical: size, weight, power, durabilityPhysical: size, weight, power, durability

Natural, topography, climate, resourcesNatural, topography, climate, resources

Company practicesCompany practices

Evaluate AlternativesEvaluate AlternativesNeeds best stated as function, not formNeeds best stated as function, not formLikely to find good alternatives for cheapest, Likely to find good alternatives for cheapest, fastest, lightest, and encourage discoveryfastest, lightest, and encourage discoveryResearch should reveal what has been doneResearch should reveal what has been doneImprove on what has been doneImprove on what has been donePlay alternatives off criteria and constraintsPlay alternatives off criteria and constraintsBrainstorming helpsBrainstorming helps

SimulationSimulation

Best DesignBest Design

Choose best design that meets criteriaChoose best design that meets criteria

Demonstrate tradeoff analyses (among Demonstrate tradeoff analyses (among criteria and constraints) is high qualitycriteria and constraints) is high quality

Cost (lifecycle) is always considerationCost (lifecycle) is always consideration

Resist overbuilding; drives complexity, Resist overbuilding; drives complexity, cost, time, resourcescost, time, resources

A quality design meets customers expectations!

PrototypePrototype

Prototype is implementation of chosen Prototype is implementation of chosen design alternativedesign alternativeIt is a proof of design, production and It is a proof of design, production and suitabilitysuitabilityPrototypes are often cost prohibitive: Prototypes are often cost prohibitive: Models and simulations may sufficeModels and simulations may sufficeQuality design does not include Quality design does not include redesigning a lot of prototypesredesigning a lot of prototypes

PrototypePrototype

Prototype

picture of 747

Test it WellTest it Well

Test and optimize design against Test and optimize design against constraints and customer expectations. constraints and customer expectations. Create a test plan showing how to testCreate a test plan showing how to testTest in the conditions of useTest in the conditions of useGood test plan shows what test, expected Good test plan shows what test, expected results how to test, and what analyses will results how to test, and what analyses will be. It relates to specification requirementsbe. It relates to specification requirements

Test and RedesignTest and Redesign

Test ResultsTest Results

Successful Test: Satisfying

Test Failure: Priceless

Project bookProject book

Project data bookProject data bookA complete record

All key decisions

Good drawings

Test plans

Results

Conclusions

Things learned

Draw a Good PictureDraw a Good Picture

• Drawings for project notebook, application, display

• Photos, sketches, CAD 2-D or 3-D

• Show assembly, components, materials

Product SketchesProduct Sketches

Other DrawingsOther Drawings

Model AbstractModel Abstract

Engineering goal ~ purpose ~ needEngineering goal ~ purpose ~ need Design and construction of gum-repelling Design and construction of gum-repelling

shoeshoe

Design and evaluation criteriaDesign and evaluation criteriaProcedures and equipment Procedures and equipment Alternatives, solution, prototype featuresAlternatives, solution, prototype features

Test plan ~ test resultsTest plan ~ test resultsConclusions Conclusions Met need? Why not? Changes? Knowledge?Met need? Why not? Changes? Knowledge?

SummarySummary

Processes ComparedProcesses Compared

HypothesisHypothesis

ExperimentExperiment

ConcludeConclude

NeedNeed

Criteria, constraintsCriteria, constraints

AlternativesAlternatives

Build prototypeBuild prototype

Test, modify, retestTest, modify, retest

SpecificationSpecification“The crux of the design

process is creating a satisfactory solution to a

need”

Design FeaturesDesign Features

1.1. Meets a need, has a “customer”Meets a need, has a “customer”

2.2. Design criteria and constraintsDesign criteria and constraints

3.3. Evaluate alternatives (systems or components)Evaluate alternatives (systems or components)

4.4. Build prototype (figuratively)Build prototype (figuratively)

5.5. Test/evaluate against test plans (criteria)Test/evaluate against test plans (criteria)

6.6. Analyze, “tweak” (Analyze, “tweak” (), redesign (), redesign (), retest), retest

7.7. Project book: record, analyses, decisions, Project book: record, analyses, decisions, specificationsspecifications

Summary: A Superior ProjectSummary: A Superior Project

A clear and relevant need from customerA clear and relevant need from customerResearch what’s been done before: don’t Research what’s been done before: don’t make theories out of facts make theories out of facts Enough criteria to develop alternative Enough criteria to develop alternative designs and perform design tradesdesigns and perform design tradesPrototype built after best design chosenPrototype built after best design chosenTest prototype as it will be usedTest prototype as it will be usedComprehensive project book, good specsComprehensive project book, good specs

Avoid These PitfallsAvoid These Pitfalls

No need, no end product

Analysis as a product

Turning facts into questions with hypotheses

Reverse engineering the process

Ah ha!, gadgetry, kits

Demonstrations, product testing

Testing without asking the user

No analysis of prototype test results

Key TermsKey Terms

Define in context and summarize here..Define in context and summarize here..

PrototypePrototype

ModelModel

SimulationSimulation

HypothesisHypothesis

Design criteriaDesign criteria

Design constraintsDesign constraints

Activity: Design CriteriaActivity: Design Criteria What should I test about a light bulb?What should I test about a light bulb?

Base fit-yes/no-first article demo

Brightness-lumens-measure

Life-hours-statistical sample

Packaging-drop test-do last

Robustness-vibration, temperature-test

article

Duty cycle-count on/off-prototype

Production assembly-time-demonstration

ActivityActivity

Teams define test requirements Teams define test requirements for a familiar thing such as MP3 for a familiar thing such as MP3 Player, Cell phone, or clothing Player, Cell phone, or clothing

and report out to classand report out to class

About the About the Scientific Scientific MethodMethod

Scientific Method(s)Scientific Method(s)Be curiousBe curious

Research Research

HypothesisHypothesis

Experiment, dataExperiment, data

Reach ConclusionsReach Conclusions

Prepare report and Prepare report and exhibitexhibit

ObserveObserve

Do researchDo research

Formulate hypothesisFormulate hypothesis

Design experimentDesign experiment

Stop. Do applicationStop. Do application

Conduct experimentsConduct experiments

Evaluate, conclusionsEvaluate, conclusions

Prep paper & exhibitPrep paper & exhibit

Prepare abstractPrepare abstract

Source: http://www.sciserv.org/isef/document/indexSource: SCVSEFA Handbook

HypothesisHypothesis

An educated guessAn educated guess

Prediction of outcomePrediction of outcome

That which can be measured and testedThat which can be measured and tested

Cause and effectCause and effect

Example: if x is true, then y will happenExample: if x is true, then y will happen

To help answer “Why”?