SVE Inc. Flag Mount Redesign

Group 4Nick Hatcher, Andrew Taylor, Neil Barnes, Jakob Combs, Chris Cook

Reason for the designMain requirements and targets

Customer/Engineering RequirementsProduct presentation

Performance demonstrationProduct evaluation

Against the engineering targetsConclusion

Current mount used by SVE Inc. was very prone to failure out in the field

Because of this, some of the customers have become unhappy with the current design

Competitors of SVE Inc. have designs which outperform the current SVE Inc. design

CUSTOMERREQUIREMENTS

Mounts to ATV Minimal Cost Fits ¼” Flag Pole Can Withstand

Flexing Ease of Assembly Detachable Short Assembly

Time Pleasing Appearance Very Durable Safe for ATV Driver

ENGINEERINGSPECIFICATIONS

Bolt/Nut Assembly $7 Target Price Fits ¼” Pole Angle of

Displacement Number of Parts Number of Steps People Liking Mount Detaches From Pole Product Lifetime Angle of Recoil

WEIGHTS

12 25 20 9 5 1 5 3 10 10

Effort was made to reduce spring recoil Keep driver and those around him/her safe

Design included ability to reuse flag pole The thumb screw and sleeve insert allows the

driver to remove the broken end of the pole and reuse the good end until it becomes undesirable because of short length. This decreases unnecessary waste produced.

Keep costs LOW! (Under $7) Added structural support to the design

Overcoming the failure mode of the current design

Increased weld strength Previous spring design used small tack weld

Increased flexibility Current design allows only 70˚ at 14 inches

above fixed mounting point Design Lifetime

The midterm design was initially chosen and built upon to create our final design.

Pro-E Concept Final Design

Pro-E Concept Final Design

Two prototypes were created which utilized springs of different wire diameter.

Prototype AWire Diameter: 0.135”

Prototype BWire Diameter: 0.105”

Although only two prototypes were created, it was decided to see what effect a rubber core insert would have on one of the prototypes. This was done as a means to effectively lower the recoil angle at a low cost.

Performance Demonstration Each prototype was benchmarked

against the Polaris competition mount using the same process of measuring the angle of recoil as measured after release from an initial displacement.

A large angular measuring device was constructed and used to do multiple recoil tests on the benchmark and the prototypes.

Apparatus used for angular measurements.

Apparatus ready for testing with Polaris flag inserted.Each prototype was tested in this manner.

From these results, data was compiled which evaluated each of the prototypes against the Polaris competition, some of which can be seen below.Initial Angle of

Displacement (deg)

Prototype A (w/ Rubber Core Insert) Recoil Angle

(deg)

Prototype A (w/o Rubber Core Insert) Recoil Angle (deg)

Prototype B Recoil Angle (deg)

10 5 11.75 820 14 19.75 1830 20.667 27.75 2640 31.167 36.5 35.550 40.833 42 4360 49.167 48.75 5270 52.83 56.25 59.580 58.833 62.25 67.590 64 68.75 73.5

Having collected this data, product evaluation could begin as it was compared to data collected from the Polaris competition mount.

All engineering requirements were met except for the $7.00 cost requirement.

This data put Prototype A w/o rubber core within 5 degrees of Polaris competition.

Polaris Spring Mount Recoil Angle(deg)

9.66617

24.33329.66638

42.66648.3355.66665

Prototype A (w/o Rubber Core Insert) Recoil Angle (deg)

11.7519.7527.7536.542

48.7556.2562.2568.75

Release Angle (deg)

102030405060708090

This can be seen in this video…

From our evaluation we concluded: Prototype A w/o rubber core met the most

customer requirements while saving cost. Although prototype uses the 0.135” diameter

wire with a spring rate of approx. 100 lbs./in., the final design will include spring provided by Lee Spring:▪ 0.135” wire diameter▪ 2.5” in length▪ 134.1 lbs./in. spring rate to bring recoil data closer

to Polaris

The following recommendations give a few ideas for which cost could be saved.

Use standard size bar stock (1”, 1.25”, etc.) Currently calling for 1.125” outer diameter

Use of less precise tolerances in design Originally called for tolerances down to

0.001”

Pre-manufactured parts could be used McMaster-Carr and CarrLane provide off-

the-shelf parts which are similar to design and could be easily implemented.

Lee Spring would provide specific spring for these parts

Other connection types could be used in design besides welding Press-fitting However, this would need to be tested

and possibly call for high tolerance values

Replace thumb screw with glue to cut costs

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