University of Wisconsin Madison

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University of WisconsinMadison
2005 SAE Clean Snowmobile Challenge Design
Presentation

• Presented by
• Eric Schroeder
• Adam Schumacher

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Design ConsiderationsMarket Survey

• Survey in Fall 2003
• 75 student riders
• Customers Want
• Acceleration
• Agility
• Historical Best Sellers
• Ski-Doo Rev Platform
• Polaris 600 XC SP
• Top speed not given high priority

• Fall 2003 Survey
• (Experienced Riders)

75 Students Surveyed
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Engine Selection
Snowmobile Engine Emissions Testing

• Engine emissions from 2002 and 2003 CSC and
  current commercial snowmobile engines
• Ski-doo SDI system reduces two stroke emissions
  by 501
• Polaris Liberty engine has lowest emissions of
  commercially available engines

SwRI 2002 (Leda, White)
1 http//www.ski-doo.com/media/2004_SOTY.pdf
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Powertrain Enhancement

• Unique Hybrid Electric Design
• Increases performance without need for larger
  engine
• Motor mounts to custom student machined chaincase

• Measured Performance Increase
• Improves acceleration from 30-60 km/hr
• Does not increase top speed of the snowmobile

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Hybrid Energy Storage

• 48 Volt Battery Pack
• 4 Johnson Controls Inspira Batteries
• 6.5 Amp-hour capacity
• Sufficient for 30 seconds of peak power
• Designed to assist the engine during acceleration
• Makes the sled feel more powerful without added
  fuel consumption and emissions

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Emissions Reduction
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Emissions Reduction

• CSC 2004 Emissions Results
• High CO and HC emissions at WOT
• Found to be open loop at WOT
• Single catalyst used in 2004

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Emissions Reduction

• Improvements for 2005
• Closed loop at WOT
• Dual Catalyst System
• Removed Secondary Air Injection

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Emissions Reduction

• 2005 Emissions Testing Results
• 94 reduction from stock
• 86 reduction from 2004

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Sound Testing
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Sound Pass By Testing
Hood Barrier
Track Skirt
Contributions of Components to Overall Noise
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Frequency Analysis of Sound
Engine
1st order Track
2nd order Track
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Sound Reduction
Track
Engine

• Two Stage Muffler System
• Catalysts
• Three Chamber Broadband Muffler

Tunnel Stiffeners
Direct Sound Barrier
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Resonance of Tunnel
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Total Sound Reduction

• Predict Sound Power Level of 107.5 dBA sound
  power based on Pass by Testing
• 43 reduction (2.5 dBA) in sound power level from
  2004 Bucky 800 HD

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Additional Features

• Electronic Throttle
• Cruise Control
• Traction Control During Launch

• Evaporative Emissions System
• Reduces HC Emissions from thermal cycling of
  fuel tank

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Projected Cost

• Only 500 higher cost than stock
• Based on 5000 sleds per year
• Difference between 700 and 900cc 2 stroke Polaris
  Snowmobiles
• 900 for a 15 increase in power

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Questions?
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Hybrid Layout
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Drivetrain Torques
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Motor Performance
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Motor Controller
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Battery Construction
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Emissions Testing Modes
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Emissions
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Emissions