ME 191 Final Presentation
Spring 2009
Team Members:
Jarret Vian
Bryan Rowley
John Murray

Introduction
 Re-Design
 Manufacturing
 Testing
 Conclusion
Minimum 60” wheel base
 Unequal front & rear track widths
 Minimum 1” ground clearance
 Minimum 2” total suspension travel
 Template must pass through frame
 Spherical bearings must be in double shear
 Design must handle applied loading


Rate of camber angle change with respect to
both body roll and wheel displacement

Original

Final Design
Manufactured at CSUS, by FSAE team

A - Arms

Bearing Holder

Hub & Spindle

Upright


Camber
Caster


Wheelbase
Track Width

Rate of camber angle change per degree
body roll
3.50
3.00
y = 0.7494x - 0.5621
R² = 0.9983
2.50
2.00
1.50
1.00
Camber
0.50
Linear (Camber)
0.00
-0.50
-1.00
0.00
2.00
4.00
6.00
Body Roll (Degrees)
Camber Angle vs. Body Roll
(Experimental)
Camber Angle (Degrees)
Camber Angle (Degrees)
Camber Angle vs. Body Roll
(Theoretical)
1.00
y = 0.7857x - 1.5119
R² = 0.9973
0.50
0.00
-0.50
Camber
-1.00
Linear (Camber)
-1.50
-2.00
0.00
1.00
2.00
3.00
Body Roll (Degrees)

Rate of camber angle change per inch of
wheel displacement
1.00
0.50
y = -0.7564x - 0.5463
R² = 0.9969
0.00
-0.50
Camber
-1.00
Linear (Camber)
-1.50
-2.00
-2.00
-1.00
0.00
1.00
2.00
Wheel Displacement (Inches)
Camber Angle vs. Wheel
Displacement (Experimental)
Camber Angle (Degrees)
Camber Angle (Degrees)
Camber Angle vs. Wheel
Displacement (Theoretical)
0.00
-0.50
-1.00
y = -0.8085x - 1.2266
R² = 0.9633
-1.50
Camber
-2.00
Linear (Camber)
-2.50
-3.00
-1.00
0.00
1.00
2.00
3.00
Wheel Displacement (Inches)

Strain Gages






Degrease
Abrade
Burnish
Condition
Neutralize
M-Bond 200

Solder

Connect to
instrumentation

Apply the load, and maintain a constant force on the tire
 139lbs, 300lbs, 400lbs
 Read the strain from each channel on the instrumentation
Load
(lbs)
Gage(s)
Rosette 1
139
Rosette 2
Rosette 3
Instrument
Channel
1
2
3
4
5
6
7
8
9
ε
γxy
ε1
ε2
(microstrain) (microstrain) (microstrain) (microstrain)
4
-18
-13
13
12
29
4
-5
-8
σ1
(psi)
σ2
(psi)
Von
Mises
(psi)
-27
11
-20
179
-556
663
-18
33
9
1,156
601
1,001
-6
5
-9
71
-238
280
Rosette 1
Von Mises Stress (psi)
3,000
2,500
y = 5.9793x
R² = 0.9812
2,000
1,500
1,000
500
0
0
50
100
150
200
250
300
350
400
Load (lbs)
Load (lbs)
759
Gage
Rosette 1
Rosette 2
Rosette 3
Von Mises (psi)
4,538
6,415
1,565

Elastic
450

Rosette location

Probe
Theoretical
Stress (psi)
Rosette 1
1,611
Rosette 2
3,358
Rosette 3
565
Gage


Experimental
Percent
Stress (psi) difference
4,538
95%
6,415
63%
1,565
94%
Sy = 50,800psi
Assumption: rigid

Assumption: smooth
Strain
gauge and accelerometer data logged
during driving

Mychron 3 data logger
with internal Accelerometer

Strain gauges
Requirement:
Wheel Base
Unequal track length
Smaller track at least 75% of larger
Minimum 2" total travel
Theoretical
≥ 60"
Experimental (Actual) Pass/Fail or % Diff
61.5"
Front: 48" Rear: 45" Front: 49" Rear: 45"
Pass
Pass
94%
92%
Pass
3"
2.625"
Pass
Template must pass throuh frame
Pass/Fail by design
Pass
Spherical bearings must be in
double shear
Pass/Fail by design
Pass
See test and analysis section
Pass
Material must not fail
Camber vs Displacement goal
-.7654 deg/in
-.8085 deg/in
6.89%
Camber vs Body Roll goal
.7494 deg/deg
.7857 deg/deg
4.84%
PREDICTED COST
ACTUAL COST
MATERIALS
1545
610
BEARINGS
246
130
HARDWARE
232
135
TOTAL
2023
875

Engineering is challenging and rewarding

Never underestimate the scope of a project

Always test to verify assumptions