Flexible Ultrasound Array Self-Calibration on Curved Objects

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing acoustic systems struggle to accurately measure curved objects due to unknown inter-element positions of transducers in flexible arrays, hindering image reconstruction.

Innovation Solution

A flexible sheet with an array of transducers determines spatial coordinates by measuring arrival times of acoustic waves from a common origin, such as a scattering element within the object, and uses wave directions and distances to model the sheet's shape, allowing for accurate reconstruction of the object's geometry.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a flexible ultrasound array is used to measure curved objects, then the adaptability to curved surfaces is improved, but the measurement precision deteriorates due to unknown inter-element positions of transducers

Engineering Contradiction:
Improveadaptability to curved surfacesVSAvoidmeasurement precision
Core Design Contradiction:
Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The system performs self-calibration by using the acoustic waves themselves to determine the positions of transducers. The calibration process is automated and does not require external intervention or predetermined geometric information, allowing the flexible array to self-correct for its unknown positions on curved surfaces

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The system changes the parameters being measured from simple acoustic reflections to time-of-flight measurements of acoustic waves. By measuring the time it takes for acoustic waves to travel between transducers and reflect off known features within the object, the system can calculate precise spatial coordinates even when the array configuration is unknown

Inventive Principle:
Principle #35Parameter changes

2Ease of operation

If the inter-element positions of transducers are unknown, then the ease of operation is improved for flexible arrays, but the reliability of image reconstruction deteriorates

Engineering Contradiction:
Improveease of operationVSAvoidreliability of image reconstruction
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The system performs preliminary calibration measurements before actual imaging. By first measuring the time-of-flight of acoustic waves to establish the spatial coordinates of all transducers, the system prepares the necessary geometric information in advance, ensuring reliable image reconstruction during subsequent imaging operations

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system uses feedback from acoustic wave measurements to continuously refine and update the spatial coordinates of transducers. The measured time-of-flight data provides feedback that allows the system to correct and verify transducer positions, ensuring accurate and reliable image reconstruction

Inventive Principle:
Principle #23Feedback

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

Enables precise measurement and imaging of curved objects by determining transducer positions and object structures using acoustic wave properties, even when transducer positions are a priori unknown.

Implementation Method 1

acoustic waves traversing and/or reflected of material substructures

Methodology Applied
Scientific EffectAcoustic wave generation and detection: Sound

Implementation Method 2

mammography and other acoustic images can be generated using pulse-echo measurements

Methodology Applied
Scientific EffectPulse-echo measurement: Echo

Implementation Method 3

the common origin is formed by one or more common scattering elements inside the curved object

Methodology Applied
Scientific EffectAcoustic scattering: Scattering

Implementation Method 4

A set of arrival times is determined of acoustic waves arriving at different transducers in the array originating from a common origin

Methodology Applied
Scientific EffectTime of flight measurement: Time of Flight

Data Source

PatentEP4384851B1Flexible ultrasound array for measuring a curved object with scattering element
Publication Date: 2026.03.18 NEDERLANDSE ORG VOOR TOEGEPAST NATUURWETENSCHAPPELIJK ONDERZOEK TNO
  • EP4384851B1 patent drawingFigure 1A~1C
  • EP4384851B1 patent drawingFigure 2A~2C
  • EP4384851B1 patent drawingFigure 3A~3B

AI summary

A system and method for acoustically measuring a curved object (Obj). A flexible sheet (20) is provided with an array of acoustic transducers (10). The flexible sheet (20) is wrapped around the curved object (Obj) such that the acoustic transducers (10) acoustically contact the curved object (Obj). The acoustic transducers (10) are used to generate and/or measure acoustic waves (W) at variable locations depending on a shape of the curved object (Obj). Spatial coordinates (X,Y,Z) of the acoustic transducers (10) are determined, while the flexible sheet (20) is wrapped around the curved object (Obj). In particular, the spatial coordinates are determined based on respective subsets of travel times (Ta,Tb,Tc) used to calculate respective wave directions of the acoustic waves (Wa,Wb,Wc) arriving at respective subarrays (10a,10b,10c) from a common origin, e.g. scattering element (S) inside the curved object (Obj).