Engineering and the Environment

REDUCING THE THREAT TO PUBLIC SAFETY: IMPROVED OBJECT CHARACTERISATION, LOCATION AND DETECTION

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 interdisciplinary mathematics and engineering 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).

The EPSRC funded interdisciplinary collaborative research project “Reducing the threat to public safety: Improved object characterisation, location and detection” is addressing these issues by developing a new theory of metal detection (MD) and applying it to the characterisation, location and detection of realistic threat items by using, and enhancing, state-of-the-art measurement equipment. The project is running from 1st January 2018 to 30th June 2021 and is in collaboration with Department of Mathematics, The University of Manchester, the School of Electrical & Electronic Engineering, The University of Manchester and the Department of Mathematics at UCL. The industrial partners are DSTL, Rapiscan Systems and Safeline.

MATHEMATICAL MODELLING OF IMPACT FORCES IN FREIGHT TRAINS

Evaluation of longitudinal forces in modern freight trains is of primary importance for their safe operation. To adequately predict the most harmful operation scenario, including the so-called coupled impacts that may significantly squeeze the carriages, their deformability, inhomogeneity, as well as energy dissipation inside the cars need to be taken into account. By taking advantage of the fact that the freight car vibrations of interest are usually of relatively low frequency, a simplified mathematical model has been derived to incorporate the aforementioned phenomena. The model provides sufficient accuracy but saves a tremendous amount of numerical simulation time. This work has been carried out in collaboration with Amsted Rail Inc., USA, and has led to a number of joint publications, e.g. 

Kaplunov, J., Shestakova, A., Aleynikov, I., & Hopkins, B. (2014). Perturbed rigid body motions of viscoelastic structures. In Proc. 9th Int. Conf. Struct. Dyn. EURODYN-2014, Porto, Portugal (pp. 3461-3464).

Kaplunov, J., Shestakova, A., Aleynikov, I., Hopkins, B., & Talonov, A. (2015). Low-frequency perturbations of rigid body motions of a viscoelastic inhomogeneous bar. Mechanics of Time-Dependent Materials, 19(2), 135-151.