Spelling suggestions: "subject:"improvised explosive device"" "subject:"improvised explosive crevice""
1 |
A graph-theory-based C-space path planner for mobile robotic manipulators in close-proximity environmentsWall, D G 10 August 2016 (has links)
In this thesis a novel guidance method for a 3-degree-of-freedom robotic manipulator arm in 3 dimensions for Improvised Explosive Device (IED) disposal has been developed. The work carried out in this thesis combines existing methods to develop a technique that delivers advantages taken from several other guidance techniques. These features are necessary for the IED disposal application. The work carried out in this thesis includes kinematic and dynamic modelling of robotic manipulators, T-space to C-space conversion, and path generation using Graph Theory to produce a guidance technique which can plan a safe path through a complex unknown environment. The method improves upon advantages given by other techniques in that it produces a suitable path in 3-dimensions in close-proximity environments in real time with no a priori knowledge of the environment, a necessary precursor to the application of this technique to IED disposal missions. To solve the problem of path planning, the thesis derives the kinematics and dynamics of a robotic arm in order to convert the Euclidean coordinates of measured environment data into C-space. Each dimension in C-space is one control input of the arm. The Euclidean start and end locations of the manipulator end effector are translated into C-space. A three-dimensional path is generated between them using Dijkstra’s Algorithm. The technique allows for a single path to be generated to guide the entire arm through the environment, rather than multiple paths to guide each component through the environment. The robotic arm parameters are modelled as a quasi-linear parameter varying system. As such it requires gain scheduling control, thus allowing compensation of the non-linearities in the system. A Genetic Algorithm is applied to tune a set of PID controllers for the dynamic model of the manipulator arm so that the generated path can then be followed using a conventional path-following algorithm. The technique proposed in this thesis is validated using numerical simulations in order to determine its advantages and limitations.
|
2 |
Detection and Monitoring of Improvised Explosive Device Education Networks Through the World Wide Web.Stinson, Robert T. III 06 1900 (has links)
As the information age comes to fruition, terrorist networks have moved mainstream by promoting their
causes via the World Wide Web. In addition to their standard rhetoric, these organizations provide anyone with an
Internet connection the ability to access dangerous information involving the creation and implementation of
Improvised Explosive Devices (IEDs). Unfortunately for governments combating terrorism, IED education networks
can be very difficult to find and even harder to monitor. Regular commercial search engines are not up to this task, as
they have been optimized to catalog information quickly and efficiently for user ease of access while promoting retail
commerce at the same time. This thesis presents a performance analysis of a new search engine algorithm designed to
help find IED education networks using the Nutch open-source search engine architecture. It reveals which web
pages are more important via references from other web pages regardless of domain. In addition, this thesis discusses
potential evaluation and monitoring techniques to be used in conjunction with the proposed algorithm.
|
3 |
A graph-theory-based C-space path planner for mobile robotic manipulators in close-proximity environmentsWall, D. G. January 2016 (has links)
In this thesis a novel guidance method for a 3-degree-of-freedom robotic manipulator arm in 3 dimensions for Improvised Explosive Device (IED) disposal has been developed. The work carried out in this thesis combines existing methods to develop a technique that delivers advantages taken from several other guidance techniques. These features are necessary for the IED disposal application. The work carried out in this thesis includes kinematic and dynamic modelling of robotic manipulators, T-space to C-space conversion, and path generation using Graph Theory to produce a guidance technique which can plan a safe path through a complex unknown environment. The method improves upon advantages given by other techniques in that it produces a suitable path in 3-dimensions in close-proximity environments in real time with no a priori knowledge of the environment, a necessary precursor to the application of this technique to IED disposal missions. To solve the problem of path planning, the thesis derives the kinematics and dynamics of a robotic arm in order to convert the Euclidean coordinates of measured environment data into C-space. Each dimension in C-space is one control input of the arm. The Euclidean start and end locations of the manipulator end effector are translated into C-space. A three-dimensional path is generated between them using Dijkstra’s Algorithm. The technique allows for a single path to be generated to guide the entire arm through the environment, rather than multiple paths to guide each component through the environment. The robotic arm parameters are modelled as a quasi-linear parameter varying system. As such it requires gain scheduling control, thus allowing compensation of the non-linearities in the system. A Genetic Algorithm is applied to tune a set of PID controllers for the dynamic model of the manipulator arm so that the generated path can then be followed using a conventional path-following algorithm. The technique proposed in this thesis is validated using numerical simulations in order to determine its advantages and limitations.
|
4 |
Photon signatures for standoff bomb detectionLoschke, Kyle W. January 1900 (has links)
Master of Science / Department of Mechanical and Nuclear Engineering / William L. Dunn / The purpose of this research was to develop a technology to quickly identify hidden explosive materials. The developed method needs to be performed at a standoff distance of approximately two meters or more, must have high sensitivity (low false-negative rate) and good specificity (low false-positive rate), and should be able to detect a minimum amount of approximately one gallon (15 lbs) of explosive material.
In an effort to meet these goals, a template-matching procedure to aid in the rapid detection of hidden improvised explosive devices was investigated. Multiple photon-scattered responses are being used as a part of a multidimensional signature-based radiation scanning (SBRS) approach in an attempt to detect chemical explosives at safe, standoff distances. The SBRS approach utilizes both neutron and photon interrogation to determine if a target contains explosive material, but the focus of this thesis is on photon interrogation.
Beams of photons are used to create back-streamed responses called signatures, which are dependent on the density and the composition of the target. These signatures are compared to templates, which are collections of the same signatures if the interrogated volume contained a significant amount of explosives. The signature analysis produces a single figure-of-merit. A low figure-of-merit indicates an explosive might be present in the target. Experiments have been conducted that show an explosive surrogate (fertilizer) can be distinguished from several inert materials using these photon signatures, proving these signatures to be very useful in this particular method of chemical explosive detection.
|
5 |
Development and Validation of a Finite Element Dummy Lower Limb Model for Under-body blast ApplicationsBaker, Wade Andrew 18 July 2017 (has links)
An under-body blast (UBB) refers to the use of a roadside explosive device to target a vehicle and its occupants. During Operation Iraqi Freedom, improvised explosive devices (IEDs) accounted for an estimated 63% of US fatalities. Furthermore, advancements in protective equipment, combat triage, and treatment have caused an increase in IED casualties surviving with debilitating injuries. Military vehicles have been common targets of IED attacks because of the potential to inflict multiple casualties.
Anthropomorphic test devices (ATDs) are mechanical human surrogates designed to transfer loads and display kinematics similar to a human subject. ATDs have been used successfully by the automotive industry for decades to quantify human injury during an impact and assess safety measures. Currently the Hybrid III ATD is used in live-fire military vehicle assessments. However, the Hybrid III was designed for frontal impacts and demonstrated poor biofidelity in vertical loading experiments.
To assess military vehicle safety and make informed improvements to vehicle design, a novel Anthropomorphic Test Device (ATD) was developed and optimized for vertical loading. ATDs, commonly referred to as crash dummies, are designed to estimate the risk of injuries to a human during an impact. The main objective of this study was to develop and validate a Finite Element (FE) model of the ATD lower limb. / Master of Science / An under-body blast (UBB) refers to the use of a roadside explosive device to target a vehicle and its occupants. During Operation Iraqi Freedom, improvised explosive devices (IEDs) accounted for an estimated 63% of US fatalities. Furthermore, advancements in protective equipment, combat triage, and treatment have caused an increase in IED casualties surviving with debilitating injuries. Military vehicles have been common targets of IED attacks because of the potential to inflict multiple casualties.
Anthropomorphic test devices (ATDs) are mechanical human surrogates designed to transfer loads and display kinematics similar to a human subject. ATDs have been used successfully by the automotive industry for decades to quantify human injury during an impact and assess safety measures. Currently the Hybrid III ATD is used in live-fire military vehicle assessments. However, the Hybrid III was designed for frontal impacts and demonstrated poor biofidelity in vertical loading experiments.
To assess military vehicle safety and make informed improvements to vehicle design, a novel Anthropomorphic Test Device (ATD) was developed and optimized for vertical loading. ATDs, commonly referred to as crash dummies, are designed to estimate the risk of injuries to a human during an impact. The main objective of this study was to develop and validate a Finite Element (FE) model of the ATD lower limb.
|
6 |
BLAST-INDUCED BRAIN INJURY: INFLUENCE OF SHOCKWAVE COMPONENTSReneer, Dexter V. 01 January 2012 (has links)
Blast-induced traumatic brain injury (bTBI) has been described as the defining injury of Operations Enduring Freedom and Iraqi Freedom (OEF/OIF). Previously, most blast injury research has focused on the effects of blast on internal, gas filled organs due to their increased susceptibility. However, due to a change in enemy tactics combined with better armor and front-line medical care, bTBI has become one of the most common injuries due to blast. Though there has been a significant amount of research characterizing the brain injury produced by blast, a sound understanding of the contribution of each component of the shockwave to the injury is needed. Large animal models of bTBI utilize chemical explosives as their shockwave source while small animal models predominantly utilize compressed air-driven membrane rupture as their shockwave source. We designed and built a multi-mode shock tube capable of utilizing compressed gas (air or helium)-driven membrane rupture or chemical explosives (oxyhydrogen – a 2:1 mixture of hydrogen and oxygen gasses, or RDX – high order explosive) to produce a shockwave. Analysis of the shockwaves produced by each mode of the McMillan Blast Device (MBD) revealed that compressed air-driven shockwaves exhibited longer duration positive phases than compressed helium-, oxyhydrogen-, or RDX-driven shockwaves of similar peak overpressure. The longer duration of compressed air-driven shockwaves results in greater energy being imparted on a test subject than would be imparted by shockwaves of identical peak overpressures from the other sources. Animals exposed to compressed air-driven shockwaves exhibited more extensive brain surface hematoma, more blood-brain barrier compromise, more extensive reactive astrocytosis, and greater numbers of activated microglia in their brains than did animals exposed to oxyhydrogen-driven shockwaves of even greater peak overpressure. Taken together, these data suggest that compressed air-driven shockwaves contain more energy than their chemical explosive-derived counterparts of equal peak overpressure and can result in greater injury in an experimental animal model. Additionally, these data suggest that exposure to longer duration shockwaves, which is common in certain realworld scenarios, can result in more severe bTBI. The results of this study can be used to aid design of blast wave mitigation technology and future clinical intervention.
|
7 |
The Detection and Identification of Explosives by Canines and Chemical InstrumentationMadison D Reavis (12445989) 12 July 2022 (has links)
<p> </p>
<p>With bombings in the United States on the rise for the first time since 2016, the detection and identification of explosives remains of pertinent interest to law enforcement agencies. This work presents two soon-to-be published research articles that focus on the detection and identification of explosives by both chemical instrumentation and canines. The first article, <em>Quantitative Analysis of Smokeless Powder Particles in Post-Blast Debris via Gas Chromatography/Vacuum Ultraviolet Spectroscopy (GC/VUV)</em>, utilizes gas chromatography/vacuum ultraviolet spectroscopy (GC/VUV) to determine the difference in chemical composition of two smokeless powders in both pre- and post-blast conditions. The compounds of interest in this study were nitroglycerin, 2,4-dinitrotoluene, diphenylamine, ethyl centralite, and di-n-butyl phthalate. Concentration changes between pre- and post-blast smokeless powder particles were determined as well as microscopic differences between pre- and post-blast debris for both smokeless powders in all devices. To our knowledge, this is the first use of GC/VUV for the quantification of explosives. The second article, <em>An Odor-Permeable Membrane Device for the Storage of Canine Training Aids</em>, proposes the use of an odor-permeable membrane device (OPMD) as a standardized storage method for canine training aids. It is hypothesized that the OPMD would minimize cross-contamination between training aids, and that the OPMD could be used for canine training as well as storage. The goal of this research is to use flux and evaporation rate to quantify the explosive odor that escapes from the OPMD compared to unconfined explosives. Preliminary data suggests that there is an exponential relationship between relative boiling point and evaporation rate. It has been determined that compounds with higher boiling points have lower evaporation rates than compounds that have lower boiling points. The materials studied thus far are known odor compounds produced by explosive formulations. These include nitromethane, nitroethane, 1-nitropropane, r-limonene, and toluene. </p>
|
Page generated in 0.0695 seconds