Nuclear quadrupole resonance system for landmine detection in Antioquia

Colombia ranks second in the world by number of victims from landmines; and in Colombia, Antioquia is the most affected department. As most landmines in Antioquia do not have metallic parts, metal detectors became useless, however, in most of those mines, the explosive mixture includes ammonium nitrate, and thus a system able to detect this compound could help to locate the mines. On the other side, nuclear quadrupole resonance (NQR) is a spectroscopic technique that allows the detection of some compounds very specifically. Thus, this work had the purpose of developing a system for remote sensing of ammonium nitrate in landmines by NQR. To achieve this goal, a portable NQR device was constructed as well as a probe, capable of sending radiofrequency pulses at the resonance frequency of ammonium nitrate, and capable of picking up the NQR signal after excitation. The manufactured system was tested against some environmental factors, concluding that the most affecting ones are soil conductivity and landmine shape. After achieving a functional system, a classifier based on spectral descriptors was trained, using data acquired with and without ammonium nitrate. Experimental results showed that the proposed classifier (an ensemble of 20 decision trees) had better performance, in terms of the area under the receiver operating characteristic curve, than the classical solution on the literature (which relies only on signal intensity). A final test validated the performance of the system, which detected four of five buried targets in an area of 2 x 1,6 m, having 3 false alarms.Resumen: Colombia es el segundo país con mayor número de víctimas por minas antipersona (MAP) en el mundo, siendo Antioquia es el departamento más afectado. La mayoría de las MAP en Antioquia contienen nitrato de amonio y la resonancia nuclear en cuadrupolo (NQR) es una técnica espectroscópica que permite detectar compuestos de forma muy específica. Así, este trabajo tiene el propósito desarrollar un sistema de NQR para la detección remota de nitrato de amonio en MAP. Para lograr este objetivo, se construyó un equipo portable de NQR, así como un inductor capaz de enviar pulsos a la frecuencia de resonancia del nitrato de amonio y de detectar la señal de NQR. El sistema construido fue probado en diferentes condiciones ambientales y se encontró que los factores que más lo afectan son la conductividad del suelo y la forma de la mina. Luego de lograr un sistema portable y funcional, se entrenó un clasificador basado en descriptores espectrales usando datos adquiridos con y sin nitrato de amonio. A partir de resultados experimentales se encontró que el clasificador entrenado (un ensamble de 20 árboles de decisión) tiene mejor desempeño, en términos del área bajo la curva de característica operativa del receptor, en comparación con la solución extendida en la literatura (que se basa únicamente en la intensidad de la señal). Una última prueba validó el desempeño del sistema, que fue capaz de detectar 5 muestras de nitrato de amonio ocultas en un área de 2 x 1,6 m, con 3 falsas alarmas.Doctorad

Guidebook on Detection Technologies and Systems for Humanitarian Demining

The aim of this publication is to provide the mine action community, and those supporting mine action, with a consolidated review and status summary of detection technologies that could be applied to humanitarian demining operations. This Guidebook is meant to provide information to a wide variety of readers. For those not familiar with the spectrum of technologies being considered for the detection of landmines and for area reduction, there is a brief overview of the principle of operation for each technology as well as a summary listing of the strengths, limitations, and potential for use of the technology to humanitarian demining. For those with an intermediate level of understanding for detection technologies, there is information regarding some of the more technical details of the system to give an expanded overview of the principles involved and hardware development that has taken place. Where possible, technical specifications for the systems are provided. For those requiring more information for a particular system, relevant publications lists and contact information are also provided

A Survey of Research on Sensor Technology for Landmine Detection

According to official figures, more than 100 million landmines lie buried around the world. Although intended for warfare, these mines remain active after warfare ends. Each day these mines are triggered accidentally by civilian activities, ravaging the land and killing or maiming innocent people. To help stop this destruction of the environment and humanity, the scientific community must develop effective humanitarian demining. Mine detection is especially vital to humanitarian demining. The goal of military demining is to clear enough mines quickly to allow troops through a land area. Military demining usually requires mine destruction rates of 80%. The goal of humanitarian demining, in contrast, is to clear enough mines to permit normal civilian use of the land (e.g., construction or agriculture). Humanitarian demining thus demands a destruction rate approaching perfection: UN specifications require a rate better than 99.6%. Of course, a critical aspect of mine clearance is mine detection. Before one can remove mines, one must locate them. To aid scientific inquiry into mine detection, this paper reviews the major current and developing technologies for mine detection. We do not claim to include every technology. Often the details of research intended for specific military applications are difficult to attain. This paper highlights significant studies of mine detection technologies, discussed in several recent conferences and in many recent articles and reports, to show promising directions for future research

Commercial Systems for the Direct Detection of Explosives (for Explosive Ordnance Disposal Tasks)

The main goal of this study, carried out by the author on behalf of the Swiss Defence Procurement Agency (DPA), was to characterise existing technologies, and identify corresponding commercially available systems, for the direct detection of explosives for Explosive Ordnance Disposal (EOD) tasks. Systems should be able to determine if a given piece of munition contains explosives or is inert, and ideally in the former case to establish the type of explosive (see also Annex A2.1). This will be often referred to in the following as the “task at hand”, or the “task of interest to us”. Note that the object in questions has already been detected by other means (usually visually, e.g. lying on the surface) – what is needed is the capacity to characterise its contents (explosive or inert)

Field detection and monitoring of explosives

Detection of explosives in situ is of major importance in several applications: finding hidden explosives in airport luggage and in mail; screening of personnel for concealed explosives; environmental monitoring of explosives-contaminated sites; and, detection of buried landmines. Mobile and hand-held detectors have been developed for the various applications. They can be sub-divided into three classes: vapor and particle detectors; radiation detectors; and, biochemical detectors. An overview of the various explosives detectors and their principles of operation is presented. (C) 2002 Published by Elsevier Science B.V. All rights reserved