Gait Index Calculation via Sensor Data Interpolation

Solution Overview

Problem

Existing gait measurement devices face challenges in reducing power consumption and communication load while maintaining accurate gait index calculation, particularly when calculating multiple gait indexes, which increases the computational and communication burden.

Innovation Solution

A gait index calculation device that receives sensor data on spatial acceleration and angular velocity at a lower frequency than normal, interpolates this data using methods like linear, polynomial, or machine learning, and calculates the gait index, thereby reducing power consumption and communication load while maintaining accuracy.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If sensor data is transmitted at normal measurement frequency to calculate multiple gait indexes, then calculation accuracy is improved, but power consumption and communication load increase

Engineering Contradiction:

Improvegait index calculation accuracyVSAvoidpower consumption

Core Design Contradiction:

Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The patent applies preliminary action by performing interpolation processing on sensor data before gait index calculation. The interpolation unit reconstructs high-frequency sensor data from low-frequency measurements in advance, allowing accurate gait index calculation without transmitting or processing large volumes of raw high-frequency data, thus reducing power consumption while maintaining accuracy

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent extracts only the essential features needed for gait analysis by interpolating sensor data to capture critical gait events (heel strike, toe-off) without transmitting complete high-frequency data streams. This extraction approach maintains measurement precision for key parameters while significantly reducing communication load and power consumption

Inventive Principle:

Principle #2Taking out (Extraction)

2Measurement precision

If sensor data is transmitted at normal measurement frequency to calculate multiple gait indexes, then calculation accuracy is improved, but communication load increases

Engineering Contradiction:

Improvegait index calculation accuracyVSAvoidcommunication load

Core Design Contradiction:

Measurement precisionVSQuantity of substance

Solution Approach 1:

The patent extracts only the essential features needed for gait analysis by interpolating sensor data to capture critical gait events (heel strike, toe-off) without transmitting complete high-frequency data streams. This extraction approach maintains measurement precision for key parameters while significantly reducing communication load

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent creates a simplified copy of the sensor data through interpolation, generating representative data points that capture the essential characteristics of gait motion. This copied data maintains accuracy for gait index calculation while occupying minimal communication bandwidth

Inventive Principle:

Principle #26Copying

3Duration of action of moving object

If measurement frequency is reduced to lower power consumption, then battery life is extended, but gait index calculation accuracy deteriorates

Engineering Contradiction:

Improvebattery lifeVSAvoidgait index calculation accuracy

Core Design Contradiction:

Duration of action of moving objectVSMeasurement precision

Solution Approach 1:

The patent applies preliminary action by performing interpolation processing on sensor data before gait index calculation. The interpolation unit reconstructs high-frequency sensor data from low-frequency measurements in advance, allowing accurate gait index calculation without transmitting or processing large volumes of raw high-frequency data, thus reducing power consumption while maintaining accuracy

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent changes the temporal parameter of data representation by transforming low-frequency raw sensor data into high-frequency interpolated data. This parameter transformation enables the system to work with reduced measurement frequency (extending battery life) while recovering the temporal resolution needed for accurate gait analysis through mathematical interpolation

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS20240277259A1Gait index calculation device, gait measurement system, gait index calculation method, and recording medium

Publication Date: 2024.08.22 NEC CORP

AI summary

Provided is a gait index calculation device that includes a communication unit that receives sensor data based on spatial acceleration and spatial angular velocity that are measured at a frequency lower than a normal measurement frequency, an interpolation unit that interpolates the sensor data using a predetermined interpolation method, a gait index calculation unit that calculates a gait index using the interpolated sensor data, and an output unit that outputs the calculated gait index.