Heated Non-Pneumatic Wheel Structure for Cryogenic Planetary Mobility
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing non-pneumatic wheels fail to provide adequate load-bearing capacity, shock absorption, and durability in extreme conditions such as those found on the Moon and Mars, particularly in permanently shaded regions where temperatures drop to -220°C to -240°C.
Innovation Solution
A deformable wheel structure with a laminated annular strip and metal cables, featuring thermal insulation and heating means for interposition layers made of hyperelastic elastomer, to maintain deformability and withstand extreme temperatures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stress or pressure
If the wheel uses a laminated strip with elastomeric interposition layers to achieve low and uniform contact pressure, then the wheel can remain mobile on soft ground, but the elastomeric material becomes too rigid below its glass transition temperature of -140°C to -150°C
Solution Approach 1:
The patent applies parameter changes by actively controlling the temperature of the elastomeric interposition layers through heating means to maintain them above the glass transition temperature. This ensures the material remains flexible and elastic at extremely low ambient temperatures (down to -240°C) by dynamically adjusting its thermal state, thus resolving the contradiction between maintaining low contact pressure and operating at extreme temperatures
Solution Approach 2:
The patent replaces the passive mechanical system with active thermal control. Instead of relying solely on the mechanical properties of elastomer at low temperatures, the invention introduces heating means and thermal insulation to actively manage the temperature parameter, substituting thermal energy input for mechanical property degradation prevention
2Reliability
If the wheel uses conventional non-pneumatic designs, then it eliminates the need for air pressure seals, but it lacks adequate load-bearing capacity and shock-absorbing capability
Solution Approach 1:
The patent applies composite materials by combining rigid ferrules with elastomeric interposition layers in a laminated structure. This composite design provides both load-bearing capacity from the rigid components and shock-absorbing capability from the elastic layers, resolving the contradiction between reliability and structural complexity
Solution Approach 2:
The patent applies segmentation by dividing the wheel structure into discrete laminated layers of ferrules and elastomeric material. This segmented approach allows each layer to perform its specific function (load support or shock absorption) while collectively providing the required reliability without excessive complexity
3Adaptability or versatility
If the wheel operates in permanently shadowed regions at -220°C to -240°C, then it can access these extreme environments, but the elastomeric material becomes brittle and loses its functional properties
Solution Approach 1:
The patent introduces thermal insulation as an intermediary between the extreme cold environment and the elastomeric material. This intermediary layer (along with active heating) mediates the thermal interaction, protecting the material from direct exposure to cryogenic temperatures and maintaining its flexibility for operational reliability
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The wheel maintains mobility on soft ground and withstands extreme temperatures by deforming to conform to the ground surface while maintaining constant ring length, ensuring vehicle mobility and structural integrity in harsh environments.
Implementation Method 1
the laminated strip is covered with at least one thermal insulation coating made from at least one material having a thermal conductivity of less than 0.2 Wm-1
Implementation Method 2
the wheel according to the invention further comprises means for heating the interposition layers of the laminated strip making it possible to distance the temperature of these interposition layers from the glass transition temperature
Implementation Method 3
the part of the laminated strip in contact with the ground deforms, not in an essentially circular shape, but in a shape that matches the surface of the ground while maintaining an essentially constant length of the ferrules
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to a deformable, non-pneumatic load-bearing wheel (2) intended for use on a vehicle for driving in extreme conditions such as those encountered on the Moon and Mars, comprising a hub (4), a laminated strip (6) comprising a plurality of ferrules assembled with interposed layers, and a plurality of metallic cables (8) connecting the hub to the laminated strip, the laminated strip being covered with at least one thermal insulation coating (20) made of at least one material having a thermal conductivity of less than 0.2 Wm-1K-1, and the wheel further comprising means (22, 24, 26) for heating the interposed layers of the laminated strip.