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The present studies are concerned with the modelling of the manufacturing process of nitrocellulose-base propellant in which cellulose acetate is substituted as a model for the explosive nitrocellulose. An investigation of the inter-relationships between processing and rheological and morphological properties has been carried out on cellulose acetate doughs, using modified torque and capillary extrusion rheometers. Some of the doughs show a yield stress and behave as Herschel-Bulkley fluids. The yield stress is found to be smaller than that of nitrocellulose doughs, and there is some evidence of shear heating. Mixing time and mixing temperature showed no influence on the rheological parameters of the doughs. These results suggest that the change in rheological properties of propellant doughs is attributed to the change in crystallinity and fibrosity after processing. The rheological properties of doughs are greatly affected by extrusion temperature, solvent, plasticiser and filler content. The interaction between the solvents and plasticisers with cellulose acetate was explained by adopting a model consisting of a rigid backbone chain from which protruded flexible side groups. In good solvents these side groups extend causing interactions between molecules, giving rise to dough up and elasticity. In poor solvents, dough up becomes difficult and the elasticity is low because the flexible side groups retract towards the stiff backbone chain. The morphology of solvated doughs is examined using solution viscometry, infrared spectroscopy, scanning electron microscope, differential scanning calorimetry, x-ray diffraction and dynamic mechanical thermal analysis. All these techniques showed that the solvation process had no significant effect on the molecular architecture of the cellulose acetate, in which the original crystallinity of the material is low. From this it was concluded that changes in the rheological properties of nitrocellulose doughs as a function of the process variables was due to changes induced in the crystallites rather than in the amorphous regions.

Nitrogen-rich energetic materials (EMs) are characterized by their typically high values for heat-of-formation as well as the environmental benefit associated with the production of nitrogen gas upon detonation. This makes them the most likely class of materials to replace currently used explosives such as lead azide (LA), 2,4,6-trinitrotoluene (TNT), and 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX). The sensitivity of EMs to mechanical stimuli such as impact and friction is governed primarily by the packing arrangement, as observed in the crystal structure. For this reason, crystal engineering is the most effective tool to achieve low sensitivity, high-performing EMs. In Chapter 2 the pH-dependent formation of two different dihydrazinyl tetrazine/azobistetrazolate salts was explored. These materials have high calculated detonation parameters and are expected to have large differences in sensitivity based on the different packing arrangements adopted. In Chapter 3, azobistetrazolate was substituted for a series of more thermally stable anions for the creation of a family of dihydrazinyltetrazine-based secondary explosives. The use of oxalyldihydrazide (ODH) as an energetic cation was explored in Chapter 4, where the selective formation of both singly and doubly protonated versions of ODH allowed for the creation of both 1:1 and 2:1 energetic salts.

Master of Science / Department of Mechanical and Nuclear Engineering / William L. Dunn / One of the most pressing threats facing the United States is the increasingly effective use of improvised explosive devices or IEDs. Many commonly used techniques to detect explosives involve imaging. The primary drawback of imaging is that it requires interpretation of one or more images from each target. Human interpretation requires extensive training and is subject to the chance of false-negatives due to human fatigue. To counter the threat posed by IEDs, the signature-based radiation scanning (SBRS) technology has been developed. The goal of this project is to create an automated system, with minimal operator assistance, that is capable of detecting at least a gallon-sized explosive sample from at least one meter away. It is hoped that this can be accomplished quickly, in less than 30 seconds, with high sensitivity and specificity. The SBRS technique is based on the fact that many classes of materials have similar stoichiometries. For example, many common explosives have characteristic concentrations of hydrogen, carbon, nitrogen and oxygen. As neutrons interact with a material, unique gamma rays are created based on the composition of the material. Specifically, in this work, the gamma rays from inelastically scattered neutrons and from thermal neutron capture are investigated. Two neutron detectors are also used, whose responses depend on neutron thermalization in and around the target. Response templates are created based on gamma-ray and neutron responses that are collected from targets that contain explosives,. These templates are developed under different conditions for many different explosive materials to create a library of templates. The collection of responses from an unknown target is compared to a subset of the library of templates using a figure of merit to distinguish benign from explosive targets. Preliminary experiments were performed at Kansas State University. A high-purity germanium detector (HPGe) was used to detect the gamma rays. Two neutron detectors, one covered with cadmium, were used to detect back-streaming neutrons. A 252Cf radioisotope source as well as a Triga Mk III reactor were used as neutron sources.

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.

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Improvised Explosive Devices (IEDs) continue to kill and seriously injure military members throughout the Iraqi theatre. Autonomous Ground Vehicle (AGV) seeks to identify the human presence placing the IED and then report that contact to a unit of action. This research developed a semi-autonomous platform that can navigate to waypoints, avoid obstacles, investigate possible threats and then detect motion that triggers a visual camera. The information is then relayed back to the user and can trigger a variety of actions. AGV has been tested in a numerous environments with a wide range of success. It is limited by the communication range from its standard 802.11G router and the continuous availability of the global positioning system. Terrain with extensive peaks and valleys is not ideal for the current platform. However, for detecting the human presence that is consistent with IED placement, AGV is well suited.

U.S. special operations forces (SOF) are likely to undertake missions against terrorists, insurgents, and other enemies where they will encounter explosive hazards. Identification, detection, and neutralization of weapons of mass destruction, improvised explosive devices, booby-traps, and similar weapons requires the support of technicians trained in explosive ordnance disposal (EOD), an expertise that is not resident in SOF units. Consequently, there is a need for EOD technicians with SOF capabilities who can readily integrate with them. This thesis employs a variety of methodologies, from an analysis of required capabilities to an application of game theory, to determine how SOF can be best supported by existing EOD forces and how the supporting command structures and relationships may be improved. It concludes that the Navy's EOD force is best suited to provide support to SOF, and should be included in all special operations planning documents. Those Navy EOD units tasked to provide support to SOF should be consolidated into one organization dedicated to that mission. Finally, when supporting SOF, the Navy should replace its current eight-person EOD operational element with a two-man team that will better match SOF operational requirements. / US Navy (USN) author.

"Submitted in partial fulfillment of the requirements for the degree of Master of Business Administration from the Naval Postgraduate School, December 2009." / Advisor(s): Boudreau, Michael ; Brinkley, Douglas. "December 2009." "MBA Professional report"--Cover. Description based on title screen as viewed on January 28, 2010. Author(s) subject terms: Notional Concept, Virtual Work Environment, Management Information System, Urgent Universal Needs Statement, share drive-based database. Includes bibliographical references (p. 65-66). Also available in print.