Department of Mechanical Science and Engineering

UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN

mechse.illinois.edu

Team 9 Transmission Project

PresentationColin Heshmat, Austin Martel, Jon Henricks, and

Peter Macknick

Department of Mechanical Science and Engineering UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN

2 Speed Transmission

Fixed Gears

Input Gears

Output

Friction ClutchInput

Engagement Disc

Bearing

Rubber

High speed Idle Low Speed

Bevel Gear

Goal:Using a $150 budget create a two speed transmission

Problems: 1. Friction Clutch2. Engagement disc shearing3. Too much overall friction

Peter

Department of Mechanical Science and Engineering UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN

2-speed Transmission + ReverseJon

Reverse Shift Fork

Reverse Gear

Reverse Gear Engagement

Pad

Identical to Project 2Setup

Goals• Improve efficiency/quality• Minimize costs• Meet new requirements

Design Modifications• Added 3 gears, 1 shaft• Increased engagement pad thickness• Installed an additional shifter• Applied Vaseline between gear teeth• Realigned shaft supports

Department of Mechanical Science and Engineering UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN

Video

Department of Mechanical Science and Engineering UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN

Performance Predictions vs. Results

• From the fundamental law of gearing: and

Theoretical angular velocity: 90 rpm

Measured peak angular velocity: 138 rpm

Theoretical maximum torque: 0.778 N*m

Measured peak torque: 0.054 N*m

• From the definition of power (the time rate of energy transfer between work):

Theoretical power output: 1.8 Watts

Measured power output: 0.254 Watts

Colin

Department of Mechanical Science and Engineering UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN

Finite Element Analysis

• Pinion 1 engagement pad– Transfers power from shaft 1 to pinion 1

– RP Part

– Nylon

• Applied point forces on each peg

• Displacement constraint on flat of hole

• Highest stress: 434 kPa– Over 100 times smaller than UTS (58 Mpa)

Austin

Department of Mechanical Science and Engineering UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN

Questions?