Segmented Insole with Eversion Module for Foot Kinematics

Solution Overview

Problem

Existing insoles fail to effectively follow the natural eversion and inversion movements of the foot during a gait cycle, leading to inadequate balance, cushioning, and propulsion.

Innovation Solution

A flexible insole design with double deformation zones that promote eversion and inversion by storing energy in the heel and releasing it to the forefoot, utilizing elastically deformable materials and varying hardness coefficients to enhance the twisting motion, accompanied by a curved blade for improved damping and propulsion.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Stability of the object's composition

If a traditional rigid insole is used, then structural support is provided, but the natural eversion and inversion movements of the foot during gait cycle are restricted

Engineering Contradiction:

Improvestructural supportVSAvoidfoot movement adaptability

Core Design Contradiction:

Stability of the object's compositionVSAdaptability or versatility

Solution Approach 1:

The insole is divided into multiple zones with different flexibility characteristics: a rigid heel zone for structural support, a flexible intermediate zone for energy storage and release, and a rigid forefoot zone for propulsion. This segmentation allows each zone to perform its specific function while collectively supporting natural foot movements.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the insole have different mechanical properties - the heel area uses harder material (Shore A 40-60) for stability, while the intermediate zone uses softer material (Shore A 20-40) for flexibility and energy storage. This local differentiation of material properties enables both structural support and movement adaptability.

Inventive Principle:

Principle #3Local quality

2Adaptability or versatility

If a flexible insole material is used, then natural foot movements are accommodated, but structural support and stability are reduced

Engineering Contradiction:

Improvefoot movement adaptabilityVSAvoidstructural support

Core Design Contradiction:

Adaptability or versatilityVSStability of the object's composition

Solution Approach 1:

The insole is divided into multiple zones with different flexibility characteristics: a rigid heel zone for structural support, a flexible intermediate zone for energy storage and release, and a rigid forefoot zone for propulsion. This segmentation allows each zone to perform its specific function while collectively supporting natural foot movements.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the insole have different mechanical properties - the heel area uses harder material (Shore A 40-60) for stability, while the intermediate zone uses softer material (Shore A 20-40) for flexibility and energy storage. This local differentiation of material properties enables both structural support and movement adaptability.

Inventive Principle:

Principle #3Local quality

3Reliability

If the insole follows natural foot kinematics with eversion and inversion zones, then balance and cushioning are improved, but device complexity increases

Engineering Contradiction:

Improvebalance and cushioning performanceVSAvoidinsole structural complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The insole is divided into four functional zones (first and second arch zones, third and fourth forefoot zones) connected by rigid joining elements. This segmentation creates a structured system that follows foot kinematics while maintaining manufacturing feasibility through modular design.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Multiple reinforcing elements (arch supports, forefoot supports, and joining elements) are integrated into a single molded structure. This merging of functions into one component achieves the complex kinematic followability while avoiding the complexity of assembling multiple separate parts.

Inventive Principle:

Principle #5Merging (Combining)

4Use of energy by moving object

If energy storage and release mechanism is implemented through double deformation zones, then propulsion efficiency is enhanced, but manufacturing complexity increases

Engineering Contradiction:

Improvepropulsion efficiencyVSAvoidinsole manufacturing simplicity

Core Design Contradiction:

Use of energy by moving objectVSEase of manufacture

Solution Approach 1:

The insole utilizes changes in material hardness (Shore A 20-60 range) and structural geometry (arch zones, forefoot zones, joining elements) to create energy storage and release characteristics. This parameter-based approach achieves propulsion efficiency through material and structural selection rather than complex mechanical mechanisms.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The insole is made from elastomeric material with varying durometer values across different zones, creating a composite structure with tailored mechanical properties. This allows energy storage in flexible zones while maintaining structural integrity in rigid zones, achieving propulsion efficiency through material composition rather than complex assembly.

Inventive Principle:

Principle #40Composite materials

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 insole design improves stability and reduces energy expenditure by naturally accompanying the foot's kinematics, enhancing balance, cushioning, and propulsion during physical activities like walking or running.

Implementation Method 1

The insole is made from an elastically deformable material... the second and fourth zones constitute a rigid support then causing a spin movement

Methodology Applied

Scientific EffectElasticity: Elasticity

Implementation Method 2

the first and second reinforcing elements consist at least partially of a rigid or semi-rigid material having respectively first and second determined hardness coefficients, the second hardness coefficient being greater than or equal to the first hardness coefficient

Methodology Applied

Scientific EffectHardness differential:

Implementation Method 3

The intermediate part comprises in its middle portion a blade substantially curved transversely and arcuate longitudinally... promote the damping phase by absorbing part of the energy

Methodology Applied

Scientific EffectDamping: Damping

Data Source

PatentEP3773045B1Flexible insole for a footwear article and orthopaedic shoe comprising such an insole

Publication Date: 2023.03.01 CZAPLICKI NATHALIE

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Figure 3~4

AI summary

The present invention relates to a flexible insole (100) which can be placed in a footwear article under the wearer's foot, said insole (100) comprising a front portion (10) and a rear portion (20) which are intended to receive the front of the foot and the heel, respectively, and a flexible intermediate portion (30) connecting the front portion (10) and the rear portion (20). The plantar face (100a) of the insole includes an eversion and inversion module (40) comprising first (41) and second (44) reinforcing elements arranged relative to each other so as to cooperate with one another in such a way that the flattening of the module (40) in the rear portion (20) causes the first (41a) and third (44a) zones to bend, thereby producing, by compensation with the second (41b) and fourth (44b) zones, the twisting of the intermediate portion (30) in the axial direction of the insole (100) and the raising of the front portion (10) relative to the intermediate portion (30).