GLASS FIBER COMPOSITE BIG

WHEEL

Kim Allen, Sam O’Flaherty, and Austin Schantz

Design NOTE: All dimensions are in inches

3D Conceptual Design

Front View

Side View

Top View

Force Calculations

Force Calculations Continued Known values

Fp=250 lbs FS=3W=575 lbs FS=3

Calculated ValuesFw=127.63 lbsFB=447.37 lbs

Force Calculations Continued Max Deflection=.1 inch

From this Max strain εmax-B=.025 εmax-w=.004545

If FB=447.37 lbs Then σB=FB/A=1.553 psi

EB= σB/ εmax-B=61.32 psi=.000422787 GPa

If Fw=127.63 lbsThen σw=Fw/A=7.977 psiEw= σw/ εmax=1755.12 psi=.0121GPa

Composite Design Theoretical Values

E1 (GPa) E2 (GPa) G (GPa) ν

In-Plane Load 3.66 1.65 0.56 0.29

Bending Load 9.09 3.37 1.08 0.28

Initial Values

Calculated Values

Note that the Emax =.0121 GPa. This composite lay-up should hold

E1 (GPa) E2 (GPa) G (GPa) νS-Glass Fiber/Epoxy 52.6 17.1 5.25 0.28

Closed Cell Foam Core

.689476 .689476 .27579 0.3

Test Section Small section with same material layup as

project

Planned Use: Find the maximum compressive and torsion load the layup could withstand

Actual Use: Identify the difficulties in manufacturing and bagging a 3-D project

Manufacturing Foam Core Construction

Hot Wire Drilling the hole for the axle

Sanding

Foam Core

Laying Up the Foam with Glass Fiber Composite

Beginning the Lay-up

The Big Wheel Bagged and ready for vacuum curing

Attaching Front yoke and Preliminary Testing

Drilling Holes for Bolts Adjusting Yolk

Making sure it holds our weight

Making Sure it Moves Smoothly

Making Sure it moves and can hold extra weight

Final Product

Testing Testing Plan

Ride around a parking lotBasic turnsRiding up a small rampTest completed 3 times

ResultsTests completed successfullyWithstood pull-up and torsion forces

Conclusion Successes

Weight rated for an adult riderWithstood forcesProject completed!!!!!

FailuresPedals slip within the hub limiting accelerationMetal components added significant weightTest section not suitable for analysis

QUESTIONS?