Buried Landmines Research Articles

Ballistic Ground Penetrating Radar Equipment for Blast-Exposed Security Applications

Among all the forensic applications in which it has become an important exploration tool, ground penetrating radar (GPR) methodology is being increasingly adopted for buried landmine localisation, a framework in which it is expected to improve the operations efficiency, given the high resolution imaging capability and the possibility of detecting both metallic and non-metallic landmines. In this context, this study presents landmine detection equipment based on multi-polarisation: a ground coupled GPR platform, which ensures suitable penetration/resolution performance without affecting the safety of surveys, thanks to the inclusion of a flexible ballistic shielding for supporting eventual blasts. The experimental results have shown that not only can the blanket absorb blast-induced flying fragments impacts, but that it also allows for the acquisition of data with the accuracy required to generate a correct 3D reconstruction of the subsurface. The produced GPR volume is then processed through an automated learning scheme based on a Convolutional Neural Network (CNN) capable of detecting buried objects with a high degree of accuracy.

Robust landmine detection from thermal image time series using Hough transform and rotationally invariant features

ABSTRACT Automated detection of buried anti-personnel landmines using remote sensing techniques is very important for clearing minefields without putting lives in danger. Although thermal infrared imaging is promising, it is far from applicable to the real world in its current state-of-the-art. The most serious problem is that experiments are generally held using sandboxes or levelled and cleared soil, but real fields are, at least partially, covered with plants. In this study, we present an algorithm for landmine detection that is robust enough to detect beyond the clutter caused by partial plant cover. The first part is a hypothesis generator based on circular Hough Transform applied to images that are filtered to enhance circular structures. The second part tests the candidate landmine coordinates using rotationally invariant features, including modified Histogram of Oriented Gaussians (HOG), over multiple images taken at different times after Wiener filtering to maximize signal-to-clutter ratio. The performances of various features and classifiers are compared. The overall performance of the algorithm is demonstrated on a dataset of real-world landmine images contaminated by simulated plants. Satisfactory results are obtained up to 40% equivalent plant coverage where more than 65% of the pixels are fully or partially covered by plants.

GPR Target Detection by Joint Sparse and Low-Rank Matrix Decomposition

Ground penetrating radar (GPR) uses electromagnetic waves to image, locate, and identify changes in electric and magnetic properties in the ground. The received signal comprises not only the target echoes but also strong reflections from the rough, uneven ground surface, which impair subsurface inspections and visualization of buried objects. In this paper, a background clutter mitigation and target detection method using low-rank and sparse priors is proposed for GPR data. The radar signal is decomposed into the sum of a low-rank component and a sparse component, plus noise. The low-rank component captures the ground surface reflections and background clutter, whereas the sparse component contains the target reflections. The effectiveness of the proposed method is evaluated on real radar signals collected from buried landmines and improvised explosive devices. The experimental results show that the proposed method successfully removes the background clutter and estimates the target signals.

Method for accurate position detection of landmine based on PGNAA technology

In the present study, the multi-detectors device was designed for landmine detection based on the MCNP simulation. With the D-T neutron generator and BGO detectors set as the core of device, boron-doping polyethylene with 5% boron was chosen for decreasing the activated noise in device. Based on the designed device, the method was proposed to detect the accurate position of buried landmine by discussing the relationship of nitrogen response between different detectors. With the calculation of simulation results, it indicated the accurate position of landmine could be acquired with a small deviation according the method. Finally, based on the established device, experimental measurement was made for furtherly investigating the validity of method.

Numerical Analysis of a Sensorized Prodder for Landmine Detection by Using its Vibrational Characteristics

Prodders are widely used devices in landmine detection. A sensorized prodder has been developed to detect shallow buried landmines by their vibrational characteristics. However, the influencing mechanisms of prodder’s components on the measured vibrational characteristics are not clear, and the vibration intensity of the buried landmine decreases with burial depth. A numerical analysis method is proposed to investigate the effects of parameters of prodder-object coupling system on the measured vibrational characteristics. The calculated main resonance frequency is 109.2 Hz, which corresponds well with the published analogy result of 110 Hz, and the mathematical method is also validated by the previous experimental results. Based on the proposed analysis method, an optimized prodder is designed, whereby the signal strength can theoretically increase 122.78%, which means that a greater depth of detection can be acquired. This optimal design is verified by the simulation experiment that was conducted with the optimization function of Adams software.

Inverse Transmission Line Modeling of GPR for Landmine Detection and Subsurface Parameter Estimation

This paper presents detection of plastic landmines and characterization of subsurface and the target using ground penetrating radar (GPR) measurements. The inverse transmission line (TL) modeling approach is used to analyze the characteristics of practical GPR system operating above non-uniform ground. The modeling approach considers the presence of surface roughness, natural clutter, targets and soil moisture. With this model, the time domain signature of electromagnetic (EM) propagation can be assessed. The inverse TL modeling is applied to estimate the characteristic parameters (such as conductivity, magnetic permeability and permittivity) of the subsurface and buried plastic landmines. TL modeling is applied to obtain the reverse solution of the electromagnetic equations. Different scenarios were considered and test signals of the B-scan data are used to test the effectiveness of the method. Simulations of the real data analysis showed the effectiveness of the model and its application to target detection and characterization of the subsurface. Performance of the modeling is analyzed using receiver operating characteristic (ROC) analysis of the four hypotheses and it has found that 99.5% detection has achieved as the cost of 12% of false alarm. Keywords : Dielectric properties; EM wave propagation; GPR; Parameter estimation; Inverse transmission line.

MCA-Based Clutter Reduction From Migrated GPR Data of Shallowly Buried Point Target

Reducing clutter is an important process in terms of improving the detection of targets when using ground penetrating radar (GPR), especially in the case of overlapping target responses and clutter. We present an alternative scheme to remove clutter from monostatic GPR data by combining migration and morphology component analysis (MCA). A simple phase shift migration is first performed on received B-scan data. In the migrated B-scan, clutter, and useful target responses exhibit different morphologies. The clutter appears to be horizontal stripes and the hyperbolic reflection from the target is refocused into an enhanced point-like shape. Subsequently, an overcomplete dictionary is constructed to discriminatively and sparsely represent each morphology based on the simulated GPR data. In particular, the 2-D undecimated discrete wavelet transform is used for the target component, and the 2-D curvelet atoms are used for the clutter. Then, the MCA technique is exploited to sparsely separate the two different components, which leads to the clutter reduction. The sparse representation of 2-D finite-difference-time-domain-based synthetic GPR data illustrates the validity of the overcomplete dictionary. In this paper, the proposed clutter removal method is tested on a synthetic model of point-like targets and real data from buried landmines. The migration concentrates the refracted signals from landmines to their origins, and the shapes of the landmines can be clearly defined. The results of the clutter reduction suggest that the proposed method is more effective than the method implemented directly on the B-scan data and the traditional mean subtraction.

Bacterial bioreporters for standoff detection of buried landmines: molecular manipulations for performance enhancement

We can now create life without the need for sperm or eggs, with the power to revolutionise fertility. Should we, asks Elie Dolgin

Aerobic Transformation of 2,4-Dinitrotoluene by Escherichia coli and Its Implications for the Detection of Trace Explosives.

DNT (2,4-dinitrotoluene), a volatile impurity in military-grade 2,4,6-trinitrotoluene (TNT)-based explosives, is a potential tracer for the detection of buried landmines and other explosive devices. We have previously described an Escherichia coli bioreporter strain engineered to detect traces of DNT and have demonstrated that the yqjF gene promoter, the sensing element of this bioreporter, is induced not by DNT but by at least one of its transformation products. In the present study, we have characterized the initial stages of DNT biotransformation in E. coli, have identified the key metabolic products in this reductive pathway, and demonstrate that the main DNT metabolite that induces yqjF is 2,4,5-trihydroxytoluene. We further show that E. coli cannot utilize DNT as a sole carbon or nitrogen source and propose that this compound is metabolized in order to neutralize its toxicity to the cells.IMPORTANCE The information provided in this article sheds new light both on the microbial biodegradability of nitroaromatic compounds and on the metabolic capabilities of E. coli By doing so, it also clarifies the pathway leading to the previously unexplained induction of the E. coli yqjF gene by 2,4-dinitrotoluene, an impurity that accompanies 2,4,6-trinitrotoluene (TNT)-based explosives. Our improved understanding of these processes will serve to molecularly enhance the performance of a previously described microbial bioreporter of buried landmines and other explosive devices, in which the yqjF gene promoter serves as the sensing element.

The importance of tuning curves and two-tone tests in nonlinear acoustic landmine detection

During the 1990s through ∼2010, Jim Sabatier’s group (Univ. Mississippi and NCPA) had made significant progress in understanding airborne acoustic landmine detection. In particular, using their development of scanning laser Doppler vibrometry, plastic anti-tank landmines could be detected in soil along roadbeds. Research on the nonlinear acoustic detection of buried landmines by Dimitry Donskoy (Stevens Tech) lead to lumped element models of the target which included a nonlinear spring-like mechanism. Tom Muir studied seismic excitations. Sabatier and Korman suggested that the soil nonlinearity and the soil interaction with the flexural vibration of the top-plate of the landmine or drum-like simulant were both significant factors in nonlinear landmine detection. Nonlinear tuning curves of the soil vibration response vs. frequency (directly over the target) along with rich combination frequency generation in two-tone tests suggested that the vibration was similar to Paul Johnson’s group results on mesoscopic nonlinear elasticity found in geomaterials. Recent airborne acoustic nonlinear landmine detection experiments compare drum-like simulant tuning curves to results using a soil plate oscillator apparatus (two circular flanges sandwiching and clamping a thin circular elastic plate that supports a cylindrical level column of sand above the plate) to help model flexural mesoscopic nonlinear hysteretic behavior.

Glowing bacteria detect buried landmines

Glowing bacteria detect buried landmines

A low-cost, portable optical explosive-vapour sensor

Humanitarian demining requires a broad range of methodologies and instrumentation for reliable identification of landmines, antipersonnel mines, and other explosive remnants of war (ERWs). Optical sensing methods are ideal for this purpose due to advantages in sensitivity, time-of-response and small form factor. In this work we present a portable photoluminescence-based sensor for nitroaromatic vapours based on the conjugated polymer Super Yellow integrated into an instrument comprising an excitation LED, photodiode, Arduino microprocessor and pumping mechanics for vapour delivery. The instrument was shown to be sensitive to few-ppb concentrations of explosive vapours under laboratory conditions, and responds to simulated buried landmine vapour. The results indicate that a lightweight, easy-to-operate, low-cost and highly-sensitive optical sensor can be readily constructed for landmine and ERW detection in the field, with potential to aid worldwide efforts in landmine mitigation.

Laser vibration sensing at Fraunhofer IOSB: review and applications

Laser vibrometry based on coherent detection allows noncontact measurements of small-amplitude vibration characteristics of objects. This technique, commonly using the Doppler effect, offers high potential for short-range civil applications and for medium- or long-range applications in defense and security. Most commercially available laser Doppler vibrometers are for short ranges (up to a few tens of meters) and use a single beam from a low-power HeNe laser source (λ=633 nm). Medium- or long-range applications need higher laser output power, and thus, appropriate vibrometers typically operate at 1.5, 2, or 10.6 μm to meet the laser safety regulations. Spatially resolved vibrational information can be obtained from an object by using scanning laser vibrometers. To reduce measuring time and to measure transient object movements and vibrational mode structures of objects, several approaches to multibeam laser Doppler vibrometry have been developed, and some of them are already commercially available for short ranges. We focus on applications in the field of defense and security, such as target classification and identification, including camouflaged or partly concealed targets, and the detection of buried land mines. Examples of civil medium-range applications are also given.

Novel Imaging Radar Technology for Detection of Landmines and Other Unexploded Ordnance

The safe, reliable, and efficient detection and subsequent removal of buried landmines or other unexploded ordnance (UXO) still remains a challenge. According to Landmine Monitor (2015), almost 60 states suffer the threat of antipersonnel mine contamination, while the total extent of contaminated areas is likely to be thousands of square kilometers and the total number of threat objects may be well over 100 million. In contrast, total annual clearing rates are in the order of about 230,000 landmines and about 200 km2 for the year of 2014, as the number of new contaminations continues to grow. Although non-technical surveillance for the identification of contamination improves slowly, more progress is needed in the basic detection of UXO. Although many new technologies have been investigated the last 20 years, the classical ones like metal detectors and dogs in cooperation with humans operators are still the most commonly ones used today. Hence, the detection process for many scenarios is unacceptably slow and dangerous for the operators, as they are typically less than 1 m away from the threats. Hence, a sensor technology enabling a sufficient stand-off distance for operators and reliable detection at high area throughput is desirable. The following paper describes the physical background, the system design, and representative measurement results of our innovative radar approach to this problem.

3D characteristic diagram of acoustically induced surface vibration with different landmines buried

The 3D characteristic diagram of acoustically induced surface vibration was employed to study the influence of different buried landmines on the acoustic detection signal. By using the vehicular experimental system for acoustic landmine detection and the method of scanning detection, the 3D characteristic diagrams of surface vibration were measured when different objects were buried underground, including big plastic landmine, small plastic landmine, big metal landmine and bricks. The results show that, under the given conditions, the surface vibration amplitudes of big plastic landmine, big metal landmine, small plastic landmine and bricks decrease in turn. The 3D characteristic diagrams of surface vibration can be used to further identify the locations of buried landmines.

Intelligent Multisensor Prodder for Training Operators in Humanitarian Demining.

Manual prodding is still one of the most utilized procedures for identifying buried landmines during humanitarian demining activities. However, due to the high number of accidents reported during its practice, it is considered an outmoded and risky procedure and there is a general consensus about the need of introducing upgrades for enhancing the safety of human operators. With the aim of contributing to reduce the number of demining accidents, this paper presents an intelligent multisensory system for training operators in the use of prodders. The proposed tool is able to provide to deminers useful information in two critical issues: (a) the amount of force exerted on the target and if it is greater than the safe limit and, (b) to alert them when the angle of insertion of the prodder is approaching or exceeding a certain dangerous limit. Results of preliminary tests show the feasibility and reliability of the proposed design and highlight the potential benefits of the tool.

Using of Boron Waste as a Shielding Material on Landmine Detection with NBS Imaging Technique

Boron wastes are produced as a result of production route of boron products and these wastes still contain a small amount of boron. In order to understand the possible use of boron waste in non-metallic landmine detection as a shielding, Monte Carlo simulations were applied by neutron backscattering imaging technique using two different neutron sources of Cf and deuterium–deuterium (D–D) reaction. NBS imaging detector system consists of a group of thermal neutron He detectors. To investigate the performance of the landmine detection system, a suitable shield around the neutron source was designed and this system was tested for localisation of buried landmine.

Standoff detection of explosives and buried landmines using fluorescent bacterial sensor cells

A standoff detection scheme for buried landmines and concealed explosive charges is presented. The detection procedure consists of the following: Live bacterial sensor strains, genetically engineered to produce a dose-dependent amount of green fluorescent protein (GFP) in the presence of explosives' vapors, are encapsulated and spread on the suspected area. The fluorescence produced by the bacteria in response to traces of the explosive material in their microenvironment is remotely detected by a phase-locked optoelectronic sampling system.This scheme enables fast direct access to a large minefield area, while obviating the need to endanger personnel and equipment. Moreover, the employment of phase locking detection efficiently isolates the bacterial sensors' fluorescent output from the background optical signals. This facilitates the application of bacterial sensors in an outdoor environment, where control of background illumination is not possible. Using this system, we demonstrate standoff detection of 2,4-DNT both in aqueous solution and when buried in soil, by sensor bacteria either in liquid culture or agar-immobilized, respectively, at a distance of 50m in a realistic optically noisy environment.

Computer-aided detection and identification of mine-like objects in infrared imagery using digital image processing

Numerous image processing algorithms are available for detection and identification of buried landmine objects from infrared IR images. There is no universal solution available for this challenging worldwide problem. While developing an algorithm for a specific database, the external factors are not taken into consideration which implies that an algorithm which gives best results for a particular database may not be effective for another database acquired from a dissimilar scenario. Nevertheless, in order to increase the robustness of the detection system, a hybrid of intelligent algorithms and newly proposed methodologies are being used in many situations yielding better results. In that view, an effort is taken to identify the feasibility of some of the available image processing algorithms for their effective application in landmine detection using IR images. The results of outdoor measurements in two different soil types are presented and the implementations of these algorithms are qualitatively and quantitatively compared.

Of Mice and Men [Turnstile

Presents information on the current state of the art in the detection of buried land mines and unexploded ordnance.