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Reverse EngineeringReverse Engineering

“ Reverse Engineering: “ Reverse Engineering: Examining competitive Examining competitive or similar or prior products in great detail by or similar or prior products in great detail by dissecting them or literally taking them apart.”dissecting them or literally taking them apart.”

-- Dym Dym & Little& Little

“What does this do?”“What does this do?”“How does it do that?”“How does it do that?”

“Why would you want to do that?”“Why would you want to do that?”

REVERSE ENGINEERING AND REVERSE ENGINEERING AND REDESIGNREDESIGN

Investigation, Prediction, and Hypothesis

Concrete experience: Function and Form

Design Models

Design Analysis

Parametric Redesign

Adaptive Redesign

Original Redesign

Reverse Engineering

Modelling and Analysis

Redesign

PROJECT IMPLEMENTATIONPROJECT IMPLEMENTATION

Phase One: “Identify product to be redesigned”Phase One: “Identify product to be redesigned”Identify at least 3 consumer products (preferably < R500; Identify at least 3 consumer products (preferably < R500; industrial sponsorship required)industrial sponsorship required)Examine product (‘black box’ model; Examine product (‘black box’ model; use; interview users; compare with use; interview users; compare with rivals) and rivals) and predict predict how the product how the product works (i.e. how it fulfills customer works (i.e. how it fulfills customer needs)needs)

Required: 1/7th scale retractable undercarriage

PROJECT IMPLEMENTATIONPROJECT IMPLEMENTATION

Phase Two: “How will you improve the product?”Phase Two: “How will you improve the product?”Disassemble products (plan, bill of materials, exploded view Disassemble products (plan, bill of materials, exploded view drawings)drawings)

Describe how product actually works (Function Structures; Describe how product actually works (Function Structures; Energy Flows)Energy Flows)Map customer needs with QFD matrix (House of Quality, i.e. Map customer needs with QFD matrix (House of Quality, i.e. matrix showing customer requirements versus functional matrix showing customer requirements versus functional requirements)requirements)

‘House of Quality’‘House of Quality’

Key: ? = 9 (strong relation) ? = 3 (some relation) Δ = 1 (weak

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Scale Appearance 9 ? 3 1

Reliable Operation 7 ? ? Δ 4 5

Durable 6 ? ? Δ 3 5

Easy to Install and Maintain 4 ? 4 5

Lightweight 1 Δ ? ? 3 5 Technical Difficulty 5 4 3 2 2

Measurement Units % n (consecutive)

‘g’ min kg

Object Target Values 90 50 3.5 15 1.7 Sierra Precision 70 50 3.5 15 1.05 Objective

Measures Spring-air 20 100 4 12 0.7 Absolute 103 81 64 36 15 Technical

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Functional requirementsFunctional requirementsRivals’Ranking

Rating

After ranking, indicatewhere opportunitiesexist to improvethe product

Functional AnalysisFunctional Analysis

Function of aircraft landing gear

PROJECT IMPLEMENTATION PROJECT IMPLEMENTATION (contd.)(contd.)

Phase One: “Identify product to be redesigned”Phase One: “Identify product to be redesigned”Phase Two: “How will you improve the product?”Phase Two: “How will you improve the product?”Phase Three: “Analysis of the redesign proposalsPhase Three: “Analysis of the redesign proposals

Meet with outside experts/practitionersMeet with outside experts/practitionersResearch of applicable engineering theory for analysisResearch of applicable engineering theory for analysisDecide on how the proposed improvements will be achievedDecide on how the proposed improvements will be achievedDevelop alternative concepts for Develop alternative concepts for affected subsystemsaffected subsystemsConcept selection using weighted Concept selection using weighted scheme and applying the scheme and applying the requirements as identified by QFDrequirements as identified by QFDPerform rigorous engineering Perform rigorous engineering analysisanalysis

SelectionSelectionCriteriaCriteria

PROJECT IMPLEMENTATION PROJECT IMPLEMENTATION (contd.)(contd.)

Phase Four: Phase Four: Synthesis Synthesis and Evaluationand Evaluation

Manufacturing Manufacturing (if possible)(if possible)Evaluation of Evaluation of improvementsimprovements

TYPICAL REDESIGN PROJECTSTYPICAL REDESIGN PROJECTS

Computerized capsule counter for use in pharmacies. Design approach: Original redesign

Radio controlled helicopter with mini-onboard video camera and 2.5GHz

real-time CCTV transmitterDesign approach: Adaptive redesign

Adjustable keyboard support for operation by wheelchair-bound disabled person Design approach: Adaptive redesign

TYPICAL REDESIGN PROJECTSTYPICAL REDESIGN PROJECTS

Human-operated Jaws of LifeDesign approach: Original

redesign

Wheelchair with manually operated hydraulic ramp for negotiating road kerbsDesign approach: Original redesign

Clever kettle featuring electronic level sensor,

and childproof on-off switch

Design approach: Adaptive redesign

Self-righting rugby tackle bagDesign approach: Adaptive redesign

DESIGN IS A PASSIONATE DESIGN IS A PASSIONATE PROCESSPROCESS

Enthusiasm is one of the most powerful engines to success. When you do a thing, do it with all your might. Put your whole soul into it. Stamp it with your own personality. Be active, be energetic, be enthusiastic and faithful and you will accomplish your object. Nothing great was ever achieved without enthusiasm.

Ralph Waldo EmersonRalph Waldo Emerson

DESIGN IS A PASSIONATE DESIGN IS A PASSIONATE PROCESSPROCESS

Use passion as a catalyst to make ideas Use passion as a catalyst to make ideas become reality:become reality:

Never stop asking:Never stop asking:•• Is this really the best I can do?Is this really the best I can do?•• Can the design be made simpler?Can the design be made simpler?

Create, never stagnateCreate, never stagnate

Focus: Focus: You can’t always get what you wantYou can’t always get what you wantBut if you try sometimes well you might findBut if you try sometimes well you might findYou get what you needYou get what you need

Mick Mick Jagger Jagger and Keith Richards, 1969and Keith Richards, 1969

Example ProjectExample ProjectBlack and Decker Hedge TrimmerBlack and Decker Hedge Trimmer

Reverse Engineering ExampleReverse Engineering Example

Reverse Engineering Reverse Engineering MethodologyMethodology

Investigation, Prediction and Hypothesis

Concrete Experience: Function & Form

Design Models

Design Analysis

Parametric Redesign

Adaptive Redesign

Original Redesign

Adapted from Otto and Wood’s “Reverse Engineering and Redesign Methodology” UT Austin

Reverse Engineering

Modeling & Analysis

Redesign

1. 1. Investigation, Prediction and HypothesisInvestigation, Prediction and HypothesisDevelop Black Box ModelDevelop Black Box Model

Assemble product and conduct a testAssemble product and conduct a testWhat goes in? What comes out? (i.e. power, noise, heat, What goes in? What comes out? (i.e. power, noise, heat, vibration)vibration)

Hedge Trimmer

NoiseElectric Power

Blade MovementFinger Switch

Safety Off Vibration, heat

Reverse Engineering Example Project

Conduct a single test of the performance of the product:•Record product performance attributes

–Shearing speed

–3300 strokes/min

–5:1 Gear reduction = 16,500 rpm for the motor

Reverse Engineering Example Project

What is the market for this product?What is the market for this product?““Suitable for small shrubbery” Suitable for small shrubbery” –– Black & Black & Decker Product CatalogueDecker Product CatalogueHomeowners with small yards and limited Homeowners with small yards and limited budgetbudgetFor use only 3For use only 3--4 times a year4 times a year

What are the costs associated with this What are the costs associated with this product?product?

Design Design -- Manufacturing Manufacturing -- Assembly Assembly ––Packaging Packaging –– Resale: R1600)Resale: R1600)

Reverse Engineering Example Project

How long will this product last?How long will this product last?Assumed durability of each component (outdoor use, Assumed durability of each component (outdoor use, dirt)dirt)Availability of replacement parts and service shopsAvailability of replacement parts and service shops

What features does this product have that are important?What features does this product have that are important?MoldedMolded--in cord retainerin cord retainerLock off switch prevents accidental startLock off switch prevents accidental start--upupLock on switch for continuous runningLock on switch for continuous runningLightweight design for less fatigue (10 kg)Lightweight design for less fatigue (10 kg)

Reverse Engineering Example Project

by: jennifer_021 (Fri Apr 7 '00) Pros: lightweight, very durableCons: none

•Trimming the bushes is my only contribution to our 2 acre yard.

•I bought my first Black & Decker hedge trimmer at Hypermarket because it was very inexpensive compared to most other trimmers

•Black & Decker has an excellent reputation.

•The 13" seemed a little too small… The 18" seemed heavier

•I also wanted electric rather than gas because being a busy woman, I had no time to learn about mixing gas.

Durability: Excellent Noise Level: Average Purchase Price: R1550.00

Additional Comments and Additional Comments and Remarks Remarks --11

REF: http://www.epinions.com/hmgd-review-5AC4-E92BC14-38EDE974-prod4

by: mchristians (Fri Apr 7 '00) Pros: Easy to handle and light too! Cons: Electric and water never mix!

•While it may be a good trimmer it also has it's downside!

•The first problem with it being electric is that you need a drop cord.

•The second problem is that since it is electric and you use it outside, you run the risk of being electrocuted! Remember most people doing lawn work are also running sprinklers to water the lawn. I have had good friends killed simply by using these trimmers on wet grass.

•Over all this tool does a great job of trimming but the hazards to your personal safety far out weigh the pros of this tool.

Durability: Good Noise Level: Average Purchase Price: R1650

Additional Comments and Additional Comments and Remarks Remarks --22

by: lpvandermerwe (Tue Jun 27 '00) Pros: Cheap, powerful, lightweightCons: Weak manual, requires an outlet.

•just about the cheapest thing you'll find on the market

•as usual the fine people at B & D come through.

•As long as the cord reaches, I have the power I need.

•safety lock located at the top of the trimmer; release the trigger, the safety clicks on

•One of the safety tips that really amused me was, “Do not use in rain.” On the one hand, I’m just not that stupid, on the other hand...well, we all know someone, don’t we? Folks, it is an electric trimmer. Do Not Use In Rain. Or the bathtub. Really.

Durability: Excellent Noise Level: Average Purchase Price: R1520.00

Additional Comments and Additional Comments and Remarks Remarks --33

After completing a search on the U.S. Patent and Trademark website:

http://www.uspto.gov

Patent # 5,778,649 (1998)

Power Driven Hedge Trimmer

Patent # 5,581,891 (1996)

Hedge Trimmer with Combination Shearing and Sawing Blade Assembly

Patent Search on Hedge TrimmersPatent Search on Hedge Trimmers

2. Concrete Experience: Function and FormCarefully begin Disassembly

Document steps and components with photographs, sketches or video

Function and Form

Hedge Trimmer SubHedge Trimmer Sub--Systems and Systems and InteractionsInteractions

Case

MotorSwitch Blade

Group defined systems and subsystems together.

120 V 120 V -- 8 ampere Motor8 ampere Motor350 rpm350 rpmWhy not batteries?Why not batteries?How important is size, How important is size,

speed?speed?Was weight a Was weight a

considerationconsideration??

Photo of Motor

Motor

Safety lock allows Safety lock allows trigger action.trigger action.Is this a regulatory Is this a regulatory requirement?requirement?Ergonomic issues Ergonomic issues of size and lever of size and lever forceforceWhat type of What type of spring mechanism spring mechanism is used?is used?

Switch

V+

-

MOTOR

Sketch of Switch

Switch

How fast do the blades need How fast do the blades need to move? Force?to move? Force?Are the blades sharp?Are the blades sharp?What are the blades made of What are the blades made of ??Can we replace the blades?Can we replace the blades?

Blades

Transmission

Input gear from motor

Output gear

Pin for upper blade

Pin for lower blade

Blades

Slot for upper blade

Slot for lower blade

How was the case made?How was the case made?Was the case designed to Was the case designed to be aesthetically pleasing?be aesthetically pleasing?Why isn’t the case made Why isn’t the case made out of metal?out of metal?What sort of costs are What sort of costs are involved in the involved in the manufacturing of this case?manufacturing of this case?

Case

Switch - Plastic Injection Molded

Gear – Die Cast Steel

Case – Plastic Injection Molded

Handle – Plastic Injection Molded

Guard – Plastic Injection Molded

Feature List

Reassemble Product

Transforming to engineering specificationsTransforming to engineering specificationsExample Example -- MotorMotor--Blade KinematicsBlade Kinematics

Helical gearsNumber of teeth: input = 4

output = 60

Motor speed = 22800 rpm

Output speed =

= 1520 rpm = 159 rad/sMaximum blade speed = 1 m/s

( )rpm 22800151

604

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Engineering Specifications

Engineering SpecificationsEngineering Specifications

Transforming to engineering Transforming to engineering specificationsspecifications1TinT

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Output gear to blades

2222112 ωIrFrFT =−−

( )φωφω cossin 2212111 rrmF −=

( )φωφω cossin 2222222 rrmF +−=

Engineering Specifications

3. Design Models3. Design ModelsIdentify actual physical principlesIdentify actual physical principlesCreate engineering models and metric Create engineering models and metric rangesrangesAlternatively or concurrently build Alternatively or concurrently build prototype to test parametersprototype to test parameters

Design Models

4. Design Analysis4. Design AnalysisCalibrate modelCalibrate modelCreate engineering analysis, simulation Create engineering analysis, simulation or optimizationor optimizationCreate experiment and testing Create experiment and testing proceduresprocedures

Design Analysis

5. Parametric Redesign5. Parametric RedesignOptimize design parametersOptimize design parametersPerform sensitivity analysis and tolerance Perform sensitivity analysis and tolerance designdesignBuild and test prototypeBuild and test prototype

Parametric Redesign

6. Adaptive Redesign6. Adaptive RedesignRecommends new subsystemsRecommends new subsystemsSearches for inventive solutionsSearches for inventive solutionsAnalyzes force flows and component Analyzes force flows and component combinationscombinationsBuilds and tests prototypeBuilds and tests prototype

Adaptive Redesign

Environmental ImpactEnvironmental ImpactTo determine the environmental To determine the environmental impact of the existing design evaluate impact of the existing design evaluate each step of the each step of the Product Life CycleProduct Life Cycle

PrePre--productionproduction

Manufacturing ProcessManufacturing Process

Product LifeProduct Life

The After LifeThe After Life

PrePre--productionproduction

Replaceability Replaceability of natural resourcesof natural resourcesAvailability of an alternative resourceAvailability of an alternative resourceEnergy required to obtainEnergy required to obtainEnergy to processEnergy to processAmount of waste created during Amount of waste created during processingprocessingWaste disposal methodWaste disposal method

Manufacturing ProcessManufacturing Process

Energy to produceEnergy to produceWaste created during productionWaste created during productionType of wasteType of waste-- solvents, solvents, emissions?emissions?Reuse of inReuse of in--process material process material waste?waste?Material yieldMaterial yield

Product LifeProduct Life

Energy consumptionEnergy consumptionWaste productionWaste productionLength of product lifeLength of product life

The After LifeThe After Life

ReuseReuseRecycleRecycle-- design for design for disassembly?disassembly?NeitherNeither-- harmful pollutants?harmful pollutants?

Discussion: Reuse vs. RecycleDiscussion: Reuse vs. Recycle

SummarySummary

Reverse engineering• Tool to understand current design

solutions and technology• Use dissection, experimentation and

analysis• Save time and gain insight on current

design challenges and solutions