Microwave Dielectric Imaging for 3D Foreign Body Detection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for detecting foreign bodies in packaged products are limited, as they either require contact or alteration of the product, or suffer from inadequate penetration and high absorption due to water content, and cannot provide a comprehensive three-dimensional map of dielectric properties.

Innovation Solution

A system and method using microwave imaging technology to spatially detect foreign bodies within products based on dielectric characteristics, generating a three-dimensional map of dielectric properties to identify foreign bodies effectively.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If microwave imaging is used to detect foreign bodies based on dielectric properties, then detection capability for low-density materials (plastic, glass) is improved, but device complexity increases compared to simple metal detectors

Engineering Contradiction:
Improvedetection capabilityVSAvoiddevice complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The microwave imaging system uses a single detection mechanism (dielectric property measurement) that can detect multiple types of foreign bodies (metal, plastic, glass, wood) uniformly, replacing the need for multiple specialized detectors. The system achieves multi-functionality by measuring dielectric contrast, which varies for different materials, allowing one device to perform what previously required multiple devices.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent replaces physical/mechanical detection methods (X-ray imaging, infrared scanning) with electromagnetic wave-based microwave imaging. This substitution enables detection based on dielectric properties rather than density or thermal properties, allowing detection of low-density materials that are invisible to X-ray and infrared methods.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Device complexity

If a two-dimensional map of dielectric properties is generated, then the system is simpler to implement, but it cannot provide complete spatial information about foreign bodies

Engineering Contradiction:
Improvesystem simplicityVSAvoidspatial information
Core Design Contradiction:
Device complexityVSLoss of information

Solution Approach 1:

The patent transitions from two-dimensional dielectric mapping to three-dimensional dielectric tomography by adding the depth dimension through microwave signal propagation analysis. Multiple antennas arranged in arrays transmit and receive microwave signals at different positions, enabling reconstruction of dielectric properties throughout the entire volume of the product, not just a cross-sectional view.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Ease of operation

If conventional detection methods are used, then the system is easier to operate, but they require contact with or alteration of the product

Engineering Contradiction:
Improveoperational simplicityVSAvoidproduct alteration
Core Design Contradiction:
Ease of operationVSObject-affected harmful factors

Solution Approach 1:

The patent replaces contact-based mechanical detection methods with non-contact electromagnetic wave-based microwave imaging. Microwaves penetrate the product and container without physical contact, detecting foreign bodies through dielectric contrast while leaving the product unchanged. This eliminates the need for opening containers, taking samples, or physically manipulating the product.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

4Device complexity

If infrared-based techniques are used for detection, then the system is simpler than microwave systems, but they suffer from limited penetration and high absorption due to water content

Engineering Contradiction:
Improvesystem complexityVSAvoiddetection reliability
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The patent changes the electromagnetic parameter from infrared frequency to microwave frequency. Microwaves have longer wavelengths and lower frequencies than infrared radiation, allowing them to penetrate water-containing products more effectively. The dielectric properties of water and food products at microwave frequencies enable deeper penetration and reduced absorption compared to infrared techniques.

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

Enables non-invasive, real-time detection of foreign bodies in products, providing a comprehensive three-dimensional analysis that aids in reducing or eliminating foreign bodies in production lines, while being cost-effective compared to X-ray systems.

Implementation Method 1

at least one plurality of antennae (210) arranged transversally to the crossing direction (L) and adapted to transmit an electromagnetic scanning signal in the microwave range

Methodology Applied
Scientific EffectElectromagnetic radiation (microwave): Electromagnetic Induction

Implementation Method 2

Each antenna (210) of said plurality of antennae (200) is adapted to transmit the electromagnetic scanning signal so as to diffuse in said product (135)

Methodology Applied
Scientific EffectDielectric properties: Dielectric Permittivity

Data Source

PatentEP4118421B1System and method for spatially detecting any foreign bodies within a product on the basis of dielectric characteristics of said product
Publication Date: 2025.01.29 FT SYST SRL
  • EP4118421B1 patent drawingFigure 1
  • EP4118421B1 patent drawingFigure 2
  • EP4118421B1 patent drawingFigure 3

AI summary

The present invention relates to a system (100) for spatially detecting any foreign bodies within a product (135) on the basis of dielectric characteristics of said product (135), said system (100) comprising: conveyor means (150) adapted to convey said product (135) through a scanning region (S) along a crossing direction (L), in a predefined crossing time interval (T) for crossing said scanning region (S); a plurality of antennae (200) arranged transversally to said crossing direction (L), wherein each antenna (210) of said plurality of antennae (200) is adapted to operate in the microwave range, and wherein each antenna (210) is adapted to transmit an electromagnetic scanning signal adapted to propagate in said scanning region (S), so as to diffuse in said product (135); processing means (250) adapted to generate a first set of values indicative of the dielectric characteristics of said product (135) based on at least one diffused electromagnetic signal received by at least one antenna (210) of said plurality of antennae (200), said processing means (250) being adapted to compare said first set of values with a second set of values indicative of the dielectric characteristics of said product (135) in the absence of any foreign bodies,wherein each antenna (210) of said plurality of antennae (200) is adapted to transmit said electromagnetic scanning signal at least once in said crossing time interval (T), according to a predefined transmission frequency.