idaho apps advanced pumpkin propulsion system

Idaho APPSAdvanced Pumpkin Propulsion System

Team MembersAndrew Schmohr

Kara Peer Shelby Smith

Josh Bouma Ramzi Sadeddinsarama

Advisor: Dr. Tom Hess Sponsor: Dr. John Foltz

ObjectiveIdaho APPSAdvanced Pumpkin Propulsion System

Design and build a pumpkin cannon for the Clearwater Corn Maze in Lewiston, ID

Needs-Quantitative• Cost less than $4000• Wheels 4” to 8” in diameter• Launch pumpkin 200 yards• Withstand 40,000 uses total• 6’ by 15’ footprint (or less)• 10” Barrel

Idaho APPSAdvanced Pumpkin Propulsion System

Needs-Qualitative

• Aesthetically pleasing• Weather protection• Aiming mechanism• Trigger lock for overnight

protection

Idaho APPSAdvanced Pumpkin Propulsion System

Wants-Quantitative

Idaho APPSAdvanced Pumpkin Propulsion System

• 1 Minute recovery time

-Qualitative• Hatch on barrel for loading• No age limit for use• No hearing protection

Zero Order Math Model

Idaho APPSAdvanced Pumpkin Propulsion System

Position as a Function of Time

Idaho APPSAdvanced Pumpkin Propulsion System

Design OptionsIdaho APPSAdvanced Pumpkin Propulsion System

3 Designs• Compressed Air• Dual Spring & Winch• Extension Spring & Pulleys

Idaho APPSAdvanced Pumpkin Propulsion System

Tank 2

Tank 1

Ball Valves

Compressor

Compressed Air Layout

Idaho APPSAdvanced Pumpkin Propulsion System

•Compressed Air Propulsion•Pumpkin Support• Sabot selection•Barrel Lubrication vs. Rollers or Bearings

The Barrel

Spring PropulsionDual Springs &

Winch

• Compression springs• Winch provides

mechanical advantage

• Winch has disconnect• Reconnection of

cable

Idaho APPSAdvanced Pumpkin Propulsion System

• Crank gear ratio of 15.8:1• Disconnect in cable provides measure

of safety• Potential for mechanical failures

Idaho APPSAdvanced Pumpkin Propulsion SystemSpring Propulsion

Dual Springs & Winch

• Springs connected to cables

• Sabot cranked back pulling the springs in tension

• Release of sabot – springs contract

Idaho APPSAdvanced Pumpkin Propulsion SystemSpring Propulsion

Extension Springs & Pulley

Idaho APPSAdvanced Pumpkin Propulsion SystemSpring Propulsion

Extension Springs & Pulley

• Smaller springs• Sabot could tangle• Inner barrel may be required to prevent

tangling• Increased barrel diameter

BaseIdaho APPSAdvanced Pumpkin Propulsion System

Idaho APPSAdvanced Pumpkin Propulsion System

• Need to be able to aim in both vertical and horizontal directions

• Swiveling plate for horizontal direction

• 2 options for vertical direction

Aiming

Idaho APPSAdvanced Pumpkin Propulsion System

• Barrel sits on swiveling plate • Plate is lockable

Horizontal Aiming

Idaho APPSAdvanced Pumpkin Propulsion System

Option 1: Rack n Pinion on

barrel

Vertical AimingOption 2:

Scissor Style carjack

Cost EstimationIdaho APPSAdvanced Pumpkin Propulsion System

Design Independent Components

Design Independent Components Subtotal

Base and WheelsBarrel – 10” SCH 80

PVCAiming MechanismFasteners &

MiscellaneousSubtotal

$ 594$ 560$ 100$ 100

10 % Contingency$

1354$ 135$

1489

Valves, Elbows, WyeCompressor

Air TanksSubtotal

10 % Contingency

$ 270$ 300$ 170$ 740$ 74

$ 814

Compressed Air Subtotal

Cost EstimationIdaho APPSAdvanced Pumpkin Propulsion System

Compressed Air

Compression Springs (4 Qty)Winch

Sabot (3/4” steel plate)Subtotal

10 % Contingency

$ 324$ 200

$ 75$ 599$ 60

$ 659

Dual Springs & Winch Subtotal

Cost EstimationIdaho APPSAdvanced Pumpkin Propulsion System

Dual Springs & Winch

Extension Springs (12 Qty)Pulleys (12 Qty)Sabot (canvas)

Subtotal10 % Contingency

$ 240$ 140

$ 25$ 405$ 41

$ 446

Extension Springs & Pulleys Subtotal

Cost EstimationIdaho APPSAdvanced Pumpkin Propulsion System

Extension Springs & Pulleys

Total Cost Estimation

Idaho APPSAdvanced Pumpkin Propulsion System

Compressed Air

Extension Springs & Pulleys

Independent Components

System Subtotal

System Total

$ 1489

$ 814

$ 2303

$ 1489 $ 1489

$ 569

$ 2058

$ 446

$ 1935

Dual Springs &

Winch

Idaho APPSAdvanced Pumpkin Propulsion System

Weight Dua

l Sp

ringsAir

Pre

ssur

e

Ease of UseCost

Ease of Design/Manufacturing

503020

100

6.276

640

7.68

6.1

742

8.868

780

Exten

sion

Sprin

gs

Decision Matrix

Higher value indicates better option