HANG TIGHTRishi Savaliya, Mitch Reid, Kelsey Barrera

AGENDA

Define the Problem Time Management Survey Brainstorming Research Donation Letters Existing Solutions Group Solutions Selecting an Approach First Prototype Second Prototype

Third Prototype Test Procedures Test Results and

Evaluation Refinements

DEFINE THE PROBLEM

Problem Statlement

According to the US Department of Transportation’s National Highway Traffic Safety Administration (NHTSA), approximately 57 million people in the United States rode a bicycle in the year 2002. The first bicycle that used a chain was invented in 1885. This resulted in the problem of bicycle chains falling off the gears. In a class of 27 students, 20 agree that bicycle chains falling is a problem that occurs very often and should be solved.

DEFINE THE PROBLEM

Statement of Purpose

Create a product that will prevent the chain from falling off the gear of a

bicycle.

GANTT CHART

SURVEY

Survey population: 145

Goals of conducting our survey Target Market Information Multiple causes of falling bicycle chains Problem Justification Product Pricing

SURVEY DATA – TARGET MARKET INFORMATION

Age groups: 14 and under 15 to 25

Ride bikes on average of 1 to 5 times weekly

SURVEY DATA – CAUSES FOR FAULTY CHAINS

15%

38%

4%

19%

24%

1%

Why Do You Ride Your Bicycle

No Answer Leisure/Hobby

Competition Transportation

Exercise Other

SURVEY DATA – PROBLEM JUSTIFICATION

88%

12%

Have You or Someone You Know Experienced Chain Prob-

lems?

Yes No

69%

20%

3%3%

6%

How Often Has This Problem Occurred?

1 to 2 Times a Year

1 to 2 Times a Month

1 to 2 Times a Week

More Often Than That

No Answer

13%

18%

55%

3%4% 7%

What Was Done To Fix Prob-lem?

Nothing

Take To Bicycle Shop

Fixed By Self

Disposed Of Bicycle

Other

No Answer

SURVEY DATA – PRODUCT PRICING

37%

26%

28%

10%

How Much Would You Pay For A Solution?

$0.01 - $3.99

$4.00 - $7.99

$8.00 - $11.00

More Than $11.00

BRAINSTORMING

Determine what specifically causes chains to fall off

Create possible designs No restraints All ideas welcome

Build off of team member’s ideas for best preliminary design

RESEARCH

Why do bike chains fall off? Decreased tension makes chain loose Misalignment of chain and sprocket

Does not mean that bike can not be used

DONATION LETTER

Explained reason for writing Asked bike manufacturers to donate

bikes Schwinn Mongoose/Pacific Cycle Trek Bicycle Raleigh America Inc. Cannondale Bicycle Corp.

Benefits to companies for contributions

EXISTING SOLUTIONS

Drive-shaft driven bicycle Eliminates chain

Patent 5078416

EXISTING SOLUTIONS

Chain catcher for bicycles Does not prevent chain from falling

Patent 5184984

EXISTING SOLUTIONS

Motorized bike with gear and chain coverPatent 6591929

GROUP SOLUTIONS

Design 1

GROUP SOLUTIONS

Design 2

GROUP SOLUTIONS

Design 3

GROUP SOLUTIONS

Design 4

CRITERIA AND CONSTRAINTS

Easy to use Aesthetics Functionality Material Cost Feasibility Adaptability

SELECT AN APPROACH

Constraint Weight Design 1 Design 2 Design 3 Design 4

Ease of Use 5 1 5 2 5

Aesthetics 2 1 5 3 4

Functionality 5 2 4 4 4

Material 3 1 1 2 3

Cost 4 1 1 2 3

Feasibility 3 1 1 4 3

Adaptability 4 1 1 1 5

Total - 31 69 66 103

DEVELOP A DESIGN PROPOSAL

Created a build process

Completed material and cost analysis

Created technical drawings for concept

FIRST PROTOTYPE

Foam

FIRST PROTOTYPE – PROBLEMS

Too large for bike Wheels on prototype don’t align Not a good material Very hard to construct Arms too far from base

NEW DESIGN

Design 5

DESIGN MATRIX

Constraint Weight Design 1 Design 2 Design 3 Design 4 Design 5

Ease of Use 5 1 5 2 5 5

Aesthetics 2 1 5 3 4 5

Functionality 5 2 4 4 4 5

Material 3 1 1 2 3 4

Cost 4 1 1 2 3 4

Feasibility 3 1 1 4 3 5

Adaptability 4 1 1 1 5 5

Total - 31 69 66 103 123

MATERIAL SELECTION MATRIX

Specification Wood Plastic Steel Cardboard Foam Aluminum

Durability 3 4 5 2 1 5

Cost 5 3 1 5 5 1

Machinability 5 5 2 5 5 2

Availability 5 5 3 5 4 3

Aesthetics 4 5 5 1 1 5

Total 22 22 16 18 16 16

SECOND PROTOTYPE

Wood

BILL OF MATERIALS – SECOND PROTOTYPE

Item Quantity Specifications Price

Wood 1 2" X 4" X 2' $ 1.98 Screws with

Bolts 2 packs of 3 1/4" 20 $ 1.49 per pack

Rubber Bands A ball of themMultiple sizes and strengths Already Owned

Total - - $ 4.90

TEST PROCEDURES

Chain Alignment Chain must stay aligned with prototype

wheels Drop Test

See effect of various riding terrains on prototype

Durability Test Chain stays aligned for a given period of

time Rider Interference

Prototype cannot prevent rider from pedaling properly

TEST RESULT AND EVALUATION

Wooden prototype passed all tests

SECOND PROTOTYPE – PROBLEMS

Lots of broken parts

Very close to wheel

Very close to pedal

REFINEMENTS

Redo dimensions Arm Wheel Base

Create new piece Attachment Piece

New Material ABS Plastic

THIRD PROTOTYPE

ABS Plastic

THIRD PROTOTYPE

Prototype with bike

BILL OF MATERIALS – THIRD PROTOTYPE

Item Quantity Specifications PriceScrews and

Bolts 2 packs of 3 1/4" 20 $1.49 per pack

Rubber Bands A ball of themMultiple sizes and strengths Pre-owned

Plastic ABS Plastic

Total - -

TEST RESULT AND EVALUATION

Duration test completed Passed

Chain alignment test completed Passed

Other tests still to be determined

THIRD PROTOTYPE – PROBLEM

Plastic is layered Easier to break

REFINEMENTS

New material Steel Aluminum

New elastic Design is still the same

FINAL PRODUCT

SUMMARY

QUESTIONS?

THANK YOU