Ultralight Airless ATV Wheels Using NPR Auxetic Structures

Solution Overview

Problem

Existing vehicle wheels lack efficient designs for ultra-lightweight, airless configurations suitable for all-terrain vehicles, particularly in terms of assembly processes and mass production considerations, which restrict their widespread adoption and performance on varied terrains.

Innovation Solution

The design incorporates flexible ring-shaped tendons and a stuffer component over a rim, with a cover bolted onto the rim to hold the tendons and stuffer in place, forming a negative Poisson ratio (NPR) auxetic structure that increases stiffness during terrain contact, using materials like fiber-reinforced composites, magnesium, or aluminum for the rim and rubber-like materials for the tendons.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Weight of moving object

If traditional wheel designs are used, then structural strength is maintained, but weight is excessive and airless configuration is not achieved

Engineering Contradiction:

Improvewheel weightVSAvoidstructural strength

Core Design Contradiction:

Weight of moving objectVSStrength

Solution Approach 1:

The wheel is divided into multiple concentric rings of unit cells, each containing V-shaped members. This segmentation allows the structure to achieve strength through geometric configuration rather than material mass, significantly reducing weight while maintaining structural integrity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent combines lightweight materials (such as aluminum or magnesium alloys) with the auxetic geometric structure to create a composite wheel that achieves both weight reduction and structural strength. The composite approach allows the lightweight materials to be optimized for their inherent properties while the geometry provides the structural framework.

Inventive Principle:

Principle #40Composite materials

2Strength

If auxetic structures are implemented, then stiffness increases during terrain contact, but manufacturing complexity increases

Engineering Contradiction:

Improvestiffness during terrain contactVSAvoidmanufacturing simplicity

Core Design Contradiction:

StrengthVSEase of manufacture

Solution Approach 1:

The wheel is divided into multiple concentric rings of unit cells, each containing V-shaped members. This segmentation allows the structure to achieve strength through geometric configuration rather than material mass, significantly reducing weight while maintaining structural integrity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent utilizes the negative Poisson's ratio property of auxetic structures, where the geometric parameters (V-shape angles, member thicknesses, spacing) are optimized to achieve the desired stiffness characteristics during terrain contact while remaining manufacturable with standard processes.

Inventive Principle:

Principle #35Parameter changes

3Adaptability or versatility

If integrated wheel-tire design is used, then performance is optimized, but assembly complexity for mass production increases

Engineering Contradiction:

Improveperformance optimizationVSAvoidassembly process complexity

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The wheel is divided into multiple concentric rings of unit cells, each containing V-shaped members. This segmentation allows the structure to achieve strength through geometric configuration rather than material mass, significantly reducing weight while maintaining structural integrity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The wheel components are designed to be pre-assembled or pre-configured in a way that simplifies the final assembly process. The modular unit cell structure allows for pre-fabrication of sections that can be quickly assembled, reducing complexity in mass production while maintaining the integrated wheel-tire performance benefits.

Inventive Principle:

Principle #10Preliminary action

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

This configuration results in an ultra-lightweight, airless wheel with enhanced stiffness during terrain contact, suitable for all-terrain vehicles, enabling efficient performance and adaptability across different terrains while allowing for cost-effective and high-volume production.

Implementation Method 1

the tendons are disposed between the V-shaped components of the stuffer and the spaced-apart surfaces to create a negative Poisson ratio (NPR) or auxetic structure, whereby the stiffness of the structure in the localized region of loading increases due to terrain contact as the wheel rotates

Methodology Applied

Scientific EffectNegative Poisson ratio (NPR) auxetic structure: Auxetic Structures

Data Source

PatentUS10315459B2Ultralightweight airless ATV wheels based upon negative Poisson ratio (NPR) auxetic structures

Publication Date: 2019.06.11 MKP STRUCTURAL DESIGN ASSOCS

AI summary

Improvements are disclosed regarding the way in which vehicle wheels are designed and assembled, including ultralight, airless vehicle wheels adapted for mounting on a rim to receive a tire. One or more flexible ring-shaped tendons are disposed over the rim. A stuffer component is disposed over the tendons, and the wheel is disposed over the stuffer. A cover is bolted onto the rim holding the stuffer and tendons in position. Importantly, the tendons, stuffer and cover are all installed onto the rim from the outside toward the vehicle, thereby easing installation and maintenance. The invention may be adapted for all-terrain vehicles, and the wheel may have diameter on the order of 7 inches, 14 inches, or any other appropriate dimensions.