1. Problem
Definition
Concept
Generation
Simulations Sample Testing
Prototype
Manufacturing
Final
Prototypes
SIMULATIONS
Homogenized Properties:
SAMPLE COMPRESSION TESTING
Simulations vs.
Compression Testing
Young's Modulus
Thermoplastic Cells
NON-PNEUMATIC CELLULAR LUNAR WHEEL
QUENTIN DERIOT, AMIT HOTCHANDANI DAYARAM, SAMIR KASSAM, JORDAN PRICE
MCGILL UNIVERSITY, MONTREAL, CANADA
RECOMMENDATIONS
• Traction can be increased by adding grousers
• Explore beyond linear-elastic behaviour, i.e. buckling
• Consider alternative manufacturing methods
i. Brazing outer band
ii. Laser cutting
• Investigate materials with high fatigue limits
FINAL PROTOTYPESPROBLEM DEFINITION
• Non-pneumatic wheels for lunar soil
• Optimization process
i. Deformability for better traction by increasing
contact surface
ii. Minimize rolling resistance to conserve energy
• Cellular structures provide a lightweight solution
with variable mechanical properties determined by
cell geometry and material
i. Density
ii. Elastic Modulus
iii. Shear Modulus
Evaluation Criteria Thermoplastic
0.275"
Aluminum
0.25"
Aluminum
0.375"
Aluminum
0.5"
Experimental E (MPa) 0.593 1.228 0.362 0.145
Theoretical E (MPa) 0.016 1.452 0.43 0.181
Error for E (%) 3603.1 15.4 15.9 20.2
Experimental ʋ 0.963 1.496 1.896 1.226
Theoretical ʋ 1 1 1 1
Error for ʋ (%) 3.8 49.6 89.6 22.6
Experimental Yield
(KPa)
35 28 21 18.5
Theoretical Yield (KPa) 7.14 36 16 9
Error for Yield (%) 390.2 22.2 31.3 105.6
Material Aluminum 3003 Aluminum 3003
Cell Size 3/8 “ 1/2 “
Mass 0.750 kg 0.612 kg
Relative
Density
0.0213 0.0160
E 0.430 MPa 0.181 MPa
G 0.019 MPa 0.008 MPa
ACKNOWLEDGEMENTS
Peter Radziszewski, Michele Faragalli, Daniel Oyama, Gary Savard
y = 0.6702x - 0.0094
y = 0.5151x + 0.0022
0
0.002
0.004
0.006
0.008
0.01
0.012
0.014
0.016
0.018
0 0.005 0.01 0.015 0.02 0.025 0.03 0.035 0.04
Stress(MPa)
Strain
Load Direction 1
Load Direction 2
Linear (Load Direction 1)
Linear (Load Direction 2)
CONCEPT GENERATION
Final Concept:
30%
25%
15%
30%
Evaluation Criteria Manufacturability
& Cost
Mechanical
Properties &
Performance
Weight
Deformability