Reducing the Threat to Public Safety: Improved metallic object characterisation, location and detection

Lead Research Organisation: University of Manchester
Department Name: Electrical and Electronic Engineering


The United Nations (UN) have announced that "With more than 30,000 foreign terrorist fighters from some 100 countries around the world, terrorism is a global threat requiring a comprehensive and unified response." This statement followed a spate of recent terrorist attacks, including those in France and Germany (July 2016), and a growing sense of global uncertainty in the western world. Promoting improvements to the identification and location of metallic threat items is an important aspect of the unified response and is an area where engineering and science can make a significant impact. Improvements in metal detection (MD) technology also provides wider benefits to the humanitarian cause of clearing landmines in developing countries. Wider benefits exist for the technology being transferred to MD companies developing devices for the non-destructive testing (NDT) of materials for safe structures, ensuring food safety, improved scrap metal sorting, as well as in medical imaging and archaeological searches.

Of course current metal detectors do find highly conductive objects and their simple design (and portability) has made them a highly cost effective modality for safety and security applications. Unfortunately, current technology is not able (or has limited capability) to distinguish between objects of different shape and materials of objects and can only detect objects within a small stand-off distance (or buried depth).

This proposal is aimed at overcoming these drawbacks through an interdisciplinary approach to improving MD technology, combing engineering, mathematics and scientific computation. Our hypothesis is that the response of metallic items in low frequency electromagnetic fields can be accurately described using a tensor based approximation. To test this hypothesis, we will develop a complete laboratory demonstration of our MD approach. This includes the following novel aspects: an efficient and adaptable software that can compute tensor coefficients for in-homogeneous objects, an algorithm for identifying different targets from field measurements with embedded uncertainty quantification as well as enhancing MD measurements by building new coil arrays based on optimised coil design. The goal is that our complete software and measurement package will lead to a step change in MD.
Description The aim of this project is to improve MD across a complete spectrum of applications by better location and discrimination of multiple objects leading to a reduction in false positives. This is being achieved through the following objectives:
1. Deeper understanding of metal detector theory based on Magnetic Polarisability Tensors (MPTs) to innovate a step change in detector design.
2. Development of a fast and accurate simulation tool for MPTs using scientific computing.
3. Improved detector design based on a deeper understanding of MD theory.
4. Validation and verification of computed MPTs using measurements for relevant applications.
5. Improving classification and discrimination of conducting objects.
Exploitation Route Through the Innovate UK project with Metrasens and Rapiscan listed under further funding.
Sectors Digital/Communication/Information Technologies (including Software),Security and Diplomacy,Transport

Description Used to support an exhibition at the Royal Society Summer Exhibition 2020
First Year Of Impact 2020
Sector Digital/Communication/Information Technologies (including Software),Security and Diplomacy,Transport
Description A novel Smart Metal Detector (SMD) to detect and locate real threats (e.g. handguns and knives) without interrupting the normal flow of public, thus leading to far more accurate, efficient and cost-effective security screening
Amount £1,366,412 (GBP)
Funding ID 39814 
Organisation Innovate UK 
Sector Public
Country United Kingdom
Start 04/2020 
End 07/2022
Description Lectureship in Personnel Screening Systems
Amount £550,000 (GBP)
Organisation Rapiscan Systems 
Sector Private
Country United States
Start 10/2019 
End 09/2024
Title Method and apparatus for determining conductivity 
Description Embodiments of the present invention provide a method of and an apparatus for determining conductivity of a metal target. An interrogation magnetic field is provided and induces an electrical current in the metal target. A resultant magnetic field is generated by the electrical current. In-phase and out-of-phase components of the resultant magnetic field are determined for the target at a first frequency (conductivity limit due to skin depth) and a second frequency of the interrogation magnetic field respectively. The conductivity of the metal target is determined based on the in-phase and out-of-phase components at the first and second frequencies. 
IP Reference PCT/GB2018/051173 
Protection Patent granted
Year Protection Granted 2018
Licensed Yes
Impact Licence with Magnapower to exploit this technology
Description Royal Society Summer Science Exhibition 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact Finding buried targets presents a serious challenge - especially in the detection and removal of anti-personnel landmines. Our research is pioneering cutting edge sub-surface detection technology for humanitarian demining. This work centres on the combination of innovative electromagnetic inspection and ground-penetrating radar, leading to safer, faster, and more effective landmine clearance.
Year(s) Of Engagement Activity 2020