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1 – 10 of 94Ricardo Castedo, Anastasio Pedro Santos, José Ignacio Yenes, José Ángel Sanchidrián, Lina María López and Pablo Segarra
The purpose of this paper is to investigate the applicability of the LS-DYNA software using a Lagrangian formulation in the jet formation, flight and penetration of improvised…
Abstract
Purpose
The purpose of this paper is to investigate the applicability of the LS-DYNA software using a Lagrangian formulation in the jet formation, flight and penetration of improvised explosively formed projectiles (EFPs). Numerical results dealing with different properties of the EFPs have been validated with a significant number of field tests.
Design/methodology/approach
2D and 3D Lagrangian models, using different material definition, are developed to reproduce the field-measured characteristics of copper- and steel-made EFPs: projectile size and velocity. After validation, the model has been extended to analyse the penetration features. Two different plasticity models have been used to describe the steel target, Plastic-Kinematic and Johnson–Cook.
Findings
Despite the difficulty in characterizing a non-industrial artefact, the results show that both Lagrangian models (2D and 3D) are able to simulate the projectile size, velocity and penetration capability with errors less than 10 per cent when using the Johnson–Cook material model for both liner and target.
Practical implications
These data can be used to test the penetration ability of improvised EFP’s against different targets, i.e. light armoured vehicles.
Originality/value
There are no references that address the application of the Lagrangian simulation of non-industrial EFPs and its validation with field tests, including penetration assessment.
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This paper aims to examine the present‐day use of, and future prospects for, robots for detecting mines and improvised explosive devices (IEDs), with an emphasis on the key…
Abstract
Purpose
This paper aims to examine the present‐day use of, and future prospects for, robots for detecting mines and improvised explosive devices (IEDs), with an emphasis on the key operational requirements.
Design/methodology/approach
Following an introduction to the impact of mines and IEDs, this paper considers the problems with their detection and considers the techniques used. It then highlights their limitations and identifies key detection requirements. The remainder of the paper discusses the present‐day and future role of robots, notably for IED detection and humanitarian demining. This is followed by a brief conclusion.
Findings
This shows that mines and IEDs pose a major military and humanitarian threat but existing detection methods, including robots, suffer from many shortcomings. Robotic technologies that offer prospects are discussed but many specific requirements must be met if robotic solutions are to exert any real, future impact.
Originality/value
This paper highlights the need for improved mine and IED detection methods and identifies the factors that need to be taken into account if robots are to contribute meaningfully to these tasks in the future.
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– The purpose of this paper is to provide details of recent developments in sensors for detecting explosives and chemical warfare agents.
Abstract
Purpose
The purpose of this paper is to provide details of recent developments in sensors for detecting explosives and chemical warfare agents.
Design/methodology/approach
Following an introduction, this paper first discusses a selection of new sensing techniques aimed at detecting explosives and explosive devices. It then considers new developments in sensors for detecting chemical warfare agents. Brief concluding comments are drawn.
Findings
This paper shows that a diversity of sensor technologies is being investigated, including various advanced optical methods, nanomaterials, microelectromechanical system, electronic noses, biosensors and electrochemical techniques, several of which offer levels of sensitivity in the parts-per-trillion region. These not only have the potential to yield improved devices for detecting explosives and chemical weapons but may also play a role in health care, environmental monitoring, drug detection and industrial health and safety.
Originality/value
In an era of escalating terrorism and military conflicts, this provides a timely review of new technologies for detecting explosives and chemical warfare agents.
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Roemi Fernández, Héctor Montes, Carlota Salinas, Pablo González de Santos and Manuel Armada
The purpose of this paper is to introduce the design of a training tool intended to improve deminers' technique during close‐in detection tasks.
Abstract
Purpose
The purpose of this paper is to introduce the design of a training tool intended to improve deminers' technique during close‐in detection tasks.
Design/methodology/approach
Following an introduction that highlights the impact of mines and improvised explosive devices (IEDs), and the importance of training for enhancing the safety and the efficiency of the deminers, this paper considers the utilization of a sensory tracking system to study the skill of the hand‐held detector expert operators. With the compiled information, some critical performance variables can be extracted, assessed, and quantified, so that they can be used afterwards as reference values for the training task. In a second stage, the sensory tracking system is used for analysing the trainee skills. The experimentation phase aims to test the effectiveness of the elements that compose the sensory system to track the hand‐held detector during the training sessions.
Findings
The proposed training tool will be able to evaluate the deminers' efficiency during the scanning tasks and will provide important information for improving their competences.
Originality/value
This paper highlights the need of introducing emerging technologies for enhancing the current training techniques for deminers and proposes a sensory tracking system that can be successfully utilised for evaluating trainees' performance with hand‐held detectors.
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This paper aims to provide a review of the uses of gas sensors to detect explosives' vapours and chemical warfare agents (CWAs).
Abstract
Purpose
This paper aims to provide a review of the uses of gas sensors to detect explosives' vapours and chemical warfare agents (CWAs).
Design/methodology/approach
Following a brief introduction, this paper first considers the use of gas sensors to detect explosives. Second, gas sensors that respond to CWAs are discussed. Some mentioned is made of commercial devices but the emphasis is on emerging technologies and recent research.
Findings
Detecting explosives is an emerging application for gas sensors. Despite some commercial products, it is the topic of a major research effort and poses a significant technological challenge due to the very low vapour concentrations involved. Many optical and solid‐state techniques are under development and some have shown ppt levels of resolution to TNT and allied compounds. Detecting CWAs is a far more mature application and many products exist, often based on analytical methods. Nevertheless, research into improved sensing techniques continues, frequently aimed at detecting ppb concentrations of nerve agents. Much of this research is aimed at meeting the needs of, and is being funded by, the US military and security agencies.
Originality/value
This paper provides a technical review of recent developments in the use of gas sensors to detect explosives and CWAs.
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Outlines the types of devices used by terrorists. Discusses how theterrorist threat can be assessed, how a building can be physicallyprotected and how the property manager should…
Abstract
Outlines the types of devices used by terrorists. Discusses how the terrorist threat can be assessed, how a building can be physically protected and how the property manager should respond to the perceived threat, both practically and reactively. Summarizes that the property manager′s security plan should consist of the identification of risks, physical protection measures, and the physical and procedural action that can be taken to reduce the risk of terrorism or deal with it should it occur.
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Last December a meeting of the SILVER Robotics Special Interest Group was held at the Land Systems Section of DERA at Chertsey, UK, and addressed the subject of robotics in…
Abstract
Last December a meeting of the SILVER Robotics Special Interest Group was held at the Land Systems Section of DERA at Chertsey, UK, and addressed the subject of robotics in military and explosive ordnance disposal (EOD) applications. Presentations speculated on the future of intelligent vehicles; battlefield engineering and robotics; the RAVEN explosive ordnance disposal system; stereo vision and virtual reality for robotics; and three papers on explosive ordnance disposal. During the lunch break there was a demonstration of some of the systems reviewed at the meeting.
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Explains a simulation system, the Wheelbarrow Mk 8 Plus control training simulator, developed by Anite Systems to be used by the army for training operators of remote vehicles for…
Abstract
Explains a simulation system, the Wheelbarrow Mk 8 Plus control training simulator, developed by Anite Systems to be used by the army for training operators of remote vehicles for making safe explosive devices.
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M. Grujicic, B. Pandurangan, G.M. Mocko, S.T. Hung, B.A. Cheeseman, W.N. Roy and R.R. Skaggs
Detonation of landmines buried to different depths in water‐saturated sand is analyzed computationally using transient non‐linear dynamics simulations in order to quantify impulse…
Abstract
Detonation of landmines buried to different depths in water‐saturated sand is analyzed computationally using transient non‐linear dynamics simulations in order to quantify impulse loading. The computational results are compared with the corresponding experimental results obtained using the Vertical Impulse Measurement Fixture (VIMF), a structural mechanical device that enables direct experimental determination of the blast‐loading impulse. The structural‐dynamic/ballistic response of the Rolled Homogenized Armor (RHA) used in the construction of the VIMF witness plate and the remainder of the VIMF and the hydrodynamic response of the TNT high‐energy explosive of a mine and of the air surrounding the VIMF are represented using the standard materials models available in literature. The structural‐dynamic/ballistic response of the sand surrounding the mine, on the other hand, is represented using our recent modified compaction model which incorporates the effects of degree of saturation and the rate of deformation, two important effects which are generally neglected in standard material models for sand. The results obtained indicate that the use of the modified compaction model yields a substantially better agreement with the experimentally‐determined impulse loads over the use the original compaction model. Furthermore, the results suggest that, in the case of fully saturated sand, the blast loading is of a bubble type rather than of a shock type, i.e. the detonation‐induced momentum transfer to the witness plate is accomplished primarily through the interaction of the sand‐over‐burden (propelled by the high‐pressure expanding gaseous detonation by‐products) with the witness plate.
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