A team of researchers and support organizations, affiliated with the Army Aviation and Missile Research, Development, and Engineering Center (AMRDEC), has initiated multidiscipline efforts to develop nano-based structures and components for advanced weaponry, aviation, and autonomous air/ground systems applications. The main objective of this research is to exploit unique phenomena for the development of novel technology to enhance warfighter capabilities and produce precision weaponry. The key technology areas that the authors are exploring include nano-based sensors, analysis of 3D printing constituents, and nano-based components for imaging detection. By integrating nano-based devices, structures, and materials into weaponry, the Army can revolutionize existing (and future) weaponry systems by significantly reducing the size, weight, and cost. The major research thrust areas include the development of carbon nanotube sensors to detect rocket motor off-gassing; the application of current methodologies to assess materials used for 3D printing; and the assessment of components to improve imaging seekers. The status of current activities, associated with these key areas and their implementation into AMRDEC’s research, is outlined in this paper. Section #2 outlines output data, graphs, and overall evaluations of carbon nanotube sensors placed on a 16 element chip and exposed to various environmental conditions. Section #3 summarizes the experimental results of testing various materials and resulting components that are supplementary to additive manufacturing/fused deposition modeling (FDM). Section #4 recapitulates a preliminary assessment of the optical and electromechanical components of seekers in an effort to propose components and materials that can work more effectively.
There is a continuous need for the Department of Defense (DoD) and its associate weaponry supply organizations to consistently evaluate the usability of weapons that exhibit deteriorative characteristics over a period of time. Along the same lines, enhanced condition-based maintenance evaluation procedures are necessary to mitigate the risk and reduce the cost of catastrophic failure of varying inventories of military systems. One significant area of research is the verification of the existence of sufficient concentrations of propellant stabilizer in the motor of stored missiles. Results from developed apparatuses can help collect degradation information to establish indicators that the missile’s double-based solid propellant is still functional after long-term storage. Other mechanisms are being developed for the assessment of degradation in gun barrel rifling. The research outlined in this paper summarizes the Army Aviation and Missile Research, Development, & Engineering Center’s (AMRDEC’s) investigative approaches relative to the use of spectral-optical and acoustical methodologies for detecting deteriorations in both propellant and the apparatus that engages munitions. A spectral-optical sensing approach is presented that is based on distinctive light collecting optical fiber –based developments designed to detect the concentration of propellant ingredients. The use of diagnostic acoustic sensing mechanisms is delineated to include the use of commercially available transducer-based readers to collect information that is indicative of the distance that acoustic waves travel through weaponry components. In collaboration with several AMRDEC industry and academia supporters, this paper outlines sensing methods that are under consideration for implementation onto weapon systems. Conceptional approaches, experimental configurations, and laboratory results are presented for each initiative. Cost-savings and improved weaponry health monitoring capabilities are expected to derive from each sensing mechanisms.
Sensing technologies are currently needed for better maintainability, reliability, safety, and monitoring small variable changes on microscopic and nanoscale systems. Plasmonic sensor research has contributed to chemical and biological sensing needs by monitoring ultrafast temporal and spatial changes in optoelectronic systems. Nonlinear plasmonic waveguides with subwavelength confinement can further enhance the capabilities of plasmonic devices. Results in this paper highlight the derivation of the full-vector Maxwell Equations for the single metal- dielectric slot waveguide and the metal –dielectric –metal waveguide with the dielectric having a Kerr-like nonlinearity. These waveguides, typically have metallic losses that compete with nonlinearity at certain frequencies that can hinder surface plasmon wave propagation. By considering temporal and spatial beam propagation in these waveguides one expects to observe novel effects that could be used for sensing applications such as femtosecond pulse propagation with plasmon self-focusing, self-trapping, and frequency conversion with reduction in metallic losses.
Researchers at the Army Aviation and Missile Research, Development, and Engineering Center (AMRDEC) have
initiated multidiscipline efforts to develop nano-based structures and components for insertion into advanced missile,
aviation, and autonomous air and ground systems. The objective of the research is to exploit unique phenomena for the
development of novel technology to enhance warfighter capabilities and produce precision weapons. The key technology
areas that the authors are exploring include nano-based microsensors, nano-energetics, nano-batteries, nano-composites,
and nano-plasmonics. By integrating nano-based devices, structures, and materials into weaponry, the Army can
revolutionize existing (and future) missile systems by significantly reducing the size, weight and cost. The major
research thrust areas include the development of chemical sensors to detect rocket motor off-gassing and toxic industrial
chemicals; the development of highly sensitive/selective, self-powered miniaturized acoustic sensors for battlefield
surveillance and reconnaissance; the development of a minimum signature solid propellant with increased ballistic and
physical properties that meet insensitive munitions requirements; the development of nano-structured material for higher
voltage thermal batteries and higher energy density storage; the development of advanced composite materials that
provide high frequency damping for inertial measurement units' packaging; and the development of metallic
nanostructures for ultraviolet surface enhanced Raman spectroscopy. The current status of the overall AMRDEC
Nanotechnology research efforts is disclosed in this paper. Critical technical challenges, for the various technologies, are
presented. The authors' approach for overcoming technical barriers and achieving required performance is also
discussed. Finally, the roadmap for each technology, as well as the overall program, is presented.
We continue a study of the equivalence particle principle applied to an optical spatial soliton which is a "narrow filament" that maintains its existence in a waveguide. Using this principle, expressions for acceleration, spatial frequency, spatial period and other variables for a spatial soliton can be derived from the solution of basic Nonlinear Schrödinger Equation. These results agree well with numerical simulations of the Modified Nonlinear Schrödinger Equation. If the expression of the acceleration is bounded in some cases this means the spatial soliton propagates with a swing effect. We go one step further in this theoretical study to investigate the effects of the swing effect with power law included in the Modified Nonlinear Schrödinger Equation.
The one-particle type temporal soliton exists by maintaining a balance between dispersive linear contributions on the one hand and non-linear effects on the other. The linear contributions occur from processes such as group velocity and polarization mode dispersion. The nonlinear features occur from Kerr, or power law non-Kerr behavior. In addition, a variety of perturbations, such as damping, Brillouin scattering, and Raman effects exist to alter the simple soliton solution. In this paper, we review the propagation of temporal solitons in power law non-Kerr media. This is developed through the higher nonlinear Schroedinger's equation (HNLSE). Also, the fundamentals of multiple-scales are presented that will be used to yield quasi-stationary solitons when perturbations are present. In waveguides, the one-particle type spatial soliton exists by maintaining a balance between the linear propagational diffraction and non-linear self-focusing, while possibly being subjected to a variety of perturbations. Here, we use a spatial optical soliton solution to the nonlinear Schroedinger equation in an inhomogeneous triangular refractive index profile as a small index perturbation to illustrate the oscillation property within a two dimensional waveguide. We determine, from the motion of spatial soliton, its effective acceleration, period of oscillation, and compare results with the Gaussian refractive index profile. Such spatial solitons behave as point masses existing in a Newtonian gravitational potential hole.
Short pulse spectral content becomes modified while propagating in dispersive media. However, in dispersive nonlinear media, optical pulses resulting in solitary waves maintain their existence if proper balance is established between nonlinear self-phase modulation on the one hand and linear dispersion on the other. Such invariance pulse shape is critical for data transfer reliability in telecommunication technologies. Robust solitary waves that emerge from collisions unaltered are called solitons. During propagation of optical solitons in inhomogeneous media their trajectories are observed to deviate from straight-line paths to that of oscillatory behavior. Here, we use a spatial optical soliton solution to the nonlinear Schrödinger equation in an inhomogeneous triangular refractive index profile as a small index perturbation to illustrate the oscillation motion. We determine the effective acceleration, give the period of oscillation, and compare results with the Gaussian refractive index profile. Such spatial solitons behave as point masses existing in a Newtonian gravitational potential hole. This novel transverse oscillatory behavior, occurring for various refractive index profiles, results from an effectively bounded acceleration.