Elastic Expansion Sensing for Automatic Nappy Fullness Detection

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing incontinence products, such as nappies, require manual checking by caregivers for soiling, which is time-consuming and can lead to discomfort or skin issues if not done regularly, and there is a need for an improved method to detect nappy fullness automatically.

Innovation Solution

A sensing device with an expandable member and detector unit is attached to or integrated with the nappy, using elastic elements to detect expansion based on nappy volume changes, providing a nappy fullness parameter.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If manual checking of nappy fullness is performed regularly, then wearer comfort and skin health are maintained, but caregiver time and effort increase significantly

Engineering Contradiction:

Improvewearer comfort and skin healthVSAvoidcaregiver time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The nappy sensing device performs self-monitoring of fullness using expandable members and detectors, eliminating the need for continuous caregiver intervention. The system serves itself by automatically detecting and reporting nappy status, while still maintaining wearer comfort through timely fullness detection.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The sensing device provides continuous feedback to caregivers about nappy fullness status through detectable signals. This feedback mechanism allows caregivers to respond only when needed, reducing unnecessary time spent on routine checks while ensuring timely intervention when the nappy is full.

Inventive Principle:

Principle #23Feedback

2Loss of time

If manual checking frequency is reduced to save time, then caregiver time decreases, but wearer comfort and skin health deteriorate

Engineering Contradiction:

Improvecaregiver timeVSAvoidwearer comfort and skin health

Core Design Contradiction:

Loss of timeVSReliability

Solution Approach 1:

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

The manual mechanical checking process is replaced with an automated sensing system using expandable members, detectors, and signal transmission mechanisms. This substitution maintains reliability by continuously monitoring nappy status without requiring frequent manual intervention.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Reliability

If sensing elements are integrated onto the nappy during manufacture, then device reliability improves, but manufacturing complexity increases

Engineering Contradiction:

Improvesensing device attachmentVSAvoidnappy manufacturing process

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The sensing device components (expandable members, detectors, attachment points) are merged with the nappy structure during manufacturing. This integration ensures reliable attachment and proper functioning of the sensing elements while allowing for streamlined production processes.

Inventive Principle:

Principle #5Merging (Combining)

4Measurement precision

If the expandable member uses elastic elements to detect expansion, then measurement precision improves, but device complexity increases

Engineering Contradiction:

Improvenappy fullness detectionVSAvoidsensing device structure

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The sensing device detects nappy fullness by monitoring changes in physical parameters of the expandable member, specifically the stretching of elastic elements. As the nappy expands with waste, the elastic elements stretch proportionally, and the detector measures this dimensional change to determine fullness status with high precision.

Inventive Principle:

Principle #35Parameter changes

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 sensing device accurately determines nappy fullness, reducing the need for manual checks and minimizing discomfort or skin issues by alerting caregivers when the nappy needs changing.

Implementation Method 1

The one or more elastic elements are configured to stretch as the attachment points move apart such that the expandable member is configured to expand in accordance with expansion of the nappy

Methodology Applied

Scientific EffectElasticity: Elasticity

Implementation Method 2

The detector unit is configured to detect expansion of the expandable member. The detector unit is further configured to determine a nappy fullness parameter based on the detected expansion of the expandable member

Methodology Applied

Scientific EffectMechanical deformation detection: Deformation

Data Source

PatentEP4319702B1Sensing device for a nappy

Publication Date: 2025.10.22 OXFORD HEALTHTECH LTD

Figure 1
Figure 2
Figure 3

AI summary

There is described a sensing device for attaching to an external surface of a nappy. The sensing device comprises an expandable member comprising one or more elastic elements extending between a plurality of attachment points, wherein the attachment points are configured to fixedly attach the expandable member to the external surface of the nappy, and wherein the one or more elastic elements are configured to stretch as the attachment points move apart such that the expandable member is configured to expand in accordance with expansion of the nappy. The sensing device further comprises a detector unit coupled to the expandable member, wherein the detector unit is configured to detect expansion of the expandable member, and is further configured to determine a nappy fullness parameter based on the detected expansion of the expandable member.