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Planetary Wheel Efficiency
The planetary wheel is also called shweel (shock-spoke wheel).
Copyright ©, 2014 LLC, 2013.
Pat. Pend. All rights reserved.
Stealth
Arm
ore
d
Air
less
Shock Crown Configuration
The shock spokes are tangential to the hub.
The planetary wheel concept
Retain air in steel, not in rubber. Thus boost safety, comfort and efficiency.
Forced eccentricity
As a flex torque coupler
Very large cushioned twist capacity.It works against slippage and wear.It reduces drivetrain maintenances.
Foam Filled
Rolling resistance
The rolling resistance expressed in road slope angle term ϑis the steepest slope on which free rolling is about to start. Higher compression ratio shocks (CR > 1:1) are more efficient.
Hardening characteristic
High compression (CR) ratio design reduces:• rolling resistance 2-4x and• drive train wear by 15-30%
Stiffness
Force
CR = 1:1
CR = 4:1
CR=1:1
CR=1:4
CR=1:2
EfficiencyEfficiency: η = 1- ϑ
Shweels ε = 1/18 ϑ = 1.8-1.9% Tires ε = 1/18 ϑ = 3.5-3.7%ε = 1/12 ϑ = 2.7-2.9% ε = 1/27 ϑ = 2.4-2.4%ε = 1/8 ϑ = 3.9-4.5% ε = 1/40 ϑ = 1.6-1.6%ε = 1/6 ϑ = 5.1-6.4% ε = 1/60 ϑ = 1.1-1.1%
Power-Losses/Rolling-Resistances:
Efficiencies:
Shweels ε = 1/18 η = 98% Tires ε = 1/18 η = 96%ε = 1/12 η = 97% ε = 1/27 η = 98%ε = 1/8 η = 95% ε = 1/40 η = 98%ε = 1/6 η = 93% ε = 1/60 η = 99%
CR=1:2 CR=1:1
Compare: Electric motors: η = 79-92% Petrol-Diesel engines: η = 20-40%.
ComparisonAt the same tire-deflections or shock-strokes, an inflated tire has at least twice as much hysteretic losses than a shweel.
For more comfort, stability and impact resistance or attenuation however, shweels have larger stroke capacities.
Shweels thus may need to pay for extra comfort by a few percent more power.
Shweels of higher compressionratio shocks are more efficient.A linear shock (CR=1:1) is the same efficient as an inflated tire.
