Skid MarkWheel and Sprocket

Decision ReportPresenter: Christopher McCrady

Christopher DodsonBrandon Holpuch

Aaron GomollAndy DavisMatt Sims

Alex PeschChristopher Curry

Outline

Configuration Summary

Safety Issues

Sprocket/Wheel Selections

System Level Configuration

Place Vehicle Drawing Here w/ Powertrain Components

Highlighted

Place Updated Picture Here

Drivetrainsub-system

Sub-System Configuration

Rim/Tire Combination

Sprockets

Safety Issues

Tire Diameter Affects Max Current

Ground Clearance

FMEA of Sprocket Clearance

RPN = (SEV) x (OCC) x (DET)

Wheels10 in. x 7 in. Rims18 in. O.D. Tires

Drive Sprocket

14 tooth, 1-7/8 in. O.D.

Smallest Available sprocket that meets horsepower needs

The American Chain Association (ACA) Improved Power Ratings for Single Strand Roller Chain

Differential Sprocket

72 tooth, 11-3/4 in. O.D.Creates 5.1 Gear Ratio

AdvantagesAvailabilityMeets performance specifications

DisadvantagesLimited gear sizes available

Solid Model Verification

1.2”

18” dia.

10” dia.

Questions?

Appendix

Wheel/Tire Decision

Size: 18” x 8.5” x 10”

Cost: $70 ea. (Plain Wheel And Tire) Shipped$100 ea. For Custom Wheels/Tires (shown above) Shipped

Size: 18” x 8.5” x 12”Cost: $130 ea. (Wheel and Tire) ShippedAlready Mounted (would need new wheels/tires for replacement)Limited Availability

Justification

FMEAMaximum current draw = 260 A (accel.)

Damage to motor or controller due to high current (max = 300 A)

Motor Decision

System Design ConsiderationsAdequate space on swingarm

Mounting on swingarm and Final Placement

Production: Perm Motor PMG-132

Prototype: Briggs and Stratton Etek½ cost of the Perm MotorEqual Performance Characteristics

Motor Selection for Production

Etek PMG-132

Max Power 17 hp 17.7 hp

Weight 22 lbs 24 lbs

Volume 0.16 ft3 0.16 ft3

Cost $350 - $450 $950

Battery Comparison

Optima 750S Trojan T1275

Capacity 55 A-h (@20 h) 150 A-h (@ 20 h)

Weight 43 lbs 82 lbs

Volume 0.31 ft3 0.56 ft3

Cost $$ Free $$ $ 160

Braking Decision

System Design Considerations

Hydraulic vs. Mechanical

PlacementLimited SpaceFunctionality

Decision – use a mechanical rear braking system

Required Brake Lever/Pedal Force

Req. Torque = 2140 in-lbs (each brake = 1070 in-lbs)

For safety, design for 1500 in-lbs for each brake

Need 75 lbs on lever

Assume mech. adv. of 4 from brake pedal – need @ 20 lbs pedal force

Refined Rear Axle/Braking System

Electrical Components

12 Volt Battery System

Use a separate battery

Separate charging portsBatteries will be differentWill cause problems when charging

LED Lights

2 ½” Round 9 Ultra BrightStop/tail/turn LED lamp.

Price – $9.99

Front/park/turn LED lamp

Price – $9.99

Accessories

Turn signal kit

Price: $39.95

Fuse Block

Price: $7.90

Accessories

Push pull light switch

Cost: $13.99

Charge Indicator

Cost: $20.99