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Garcia E.,Infoscitex Corporation | Antsaklis P.J.,University of Notre Dame
Systems and Control Letters | Year: 2013

This paper presents a model-based control approach for output feedback stabilization and disturbance attenuation of continuous time systems that transmit measurements over a limited bandwidth communication network. Necessary and sufficient conditions for asymptotic stability of the networked system in the presence of persistent external disturbances are given. The results in this paper provide a significant improvement in the performance of the system and provide a considerably reduction of the necessary network bandwidth with respect to similar approaches in the literature. © 2013 Elsevier B.V. All rights reserved. Source

Garcia E.,University of Notre Dame | Garcia E.,Infoscitex Corporation | Antsaklis P.J.,University of Notre Dame
IEEE Transactions on Automatic Control | Year: 2013

This paper combines two important control techniques for reducing communication traffic in control networks, namely, model-based networked control systems (MB-NCS) and event-triggered control. The resulting framework is used for stabilization of uncertain dynamical systems and is extended to systems subject to quantization and time-varying network delays. The use of a model of the plant in the controller node not only generalizes the zero-order-hold (ZOH) implementation in traditional event-triggered control schemes but it also provides stability thresholds that are robust to model uncertainties. The effects of quantized measurements are especially important in the selection of stabilizing thresholds. We are able to design error events based on the quantized variables that yield asymptotic stability compared to similar results in event-triggered control that consider nonquantized measurements which, in general, are not possible to use in digital computations. With respect to MB-NCS, the stability conditions presented here do not need explicit knowledge of the plant parameters as in previous work but are given only in terms of the parameters of the nominal model and some bounds in the model uncertainties. We consider the joint adverse effects of quantization and time delays and emphasize the expected tradeoff between the selection of quantization parameters and the admissible network induced delays. © 2012 IEEE. Source

Agency: Department of Defense | Branch: Air Force | Program: SBIR | Phase: Phase I | Award Amount: 149.98K | Year: 2012

ABSTRACT: Exposure to hexavalent chromium (Cr(VI)) poses significant health risks to personnel involved in processing chromium containing materials. Therefore, thorough cleaning of residues of material containing Cr(VI) is extremely important. The soaps used currently to clean the areas contaminated with Cr(VI) negatively affect with processes of heavy metal recovery from washdown and waste waters. This is caused by competitive binding of the active soap ingredients to the heavy-metal ions; thus, the chelating agent and ion exchanges cannot react with the metal cations. In order to mitigate the problems created by the use of regular soaps, a designer soap, that is process friendly, allows complete removal of the Cr(VI) materials from contaminated surfaces, and does not reduce the efficiency of heavy metal collection from washdown and waste waters needs to be used is needed to be used in the designated work areas. In response to this problem, Infoscitex Corporation (IST) has developed a concept for a novel designer soap that will Efficiently remove Cr(VI) contamination Be inert towards recoverable heavy metal cations Be environmentally friendly and inexpensive BENEFIT: Military Application: Most DoD paint/depaint operations run their waste water thru an industrial waste water treatment plant for treatment to remove regulated wastes. Each DoD facility would benefit from such a soap. Commercial Application: Commercial paint and depaint facilities could benefit from a designer soap that would not interfere with the treatment of metals at the industrial waste treatment facilities.

Agency: Department of Defense | Branch: Air Force | Program: SBIR | Phase: Phase I | Award Amount: 149.90K | Year: 2012

ABSTRACT: The continually expanding role technology plays on the modern battlefield is resulting in Warfighters having to carry more batteries. This increased battery weight puts additional strain on the Warfighter and increases logistical burden. In response to these issues, the Air Force has created a power generation and management system (PG & M) that acts as a central power source that can be used to recharge multiple devices. Currently, devices are attached to the PG & M system via conventional cables and connectors. These cables and connectors represent the weak points in the system in that connectors can become damaged or fouled to the point of not being useable, and cables represent snag hazards and hard points. Infoscitex (IST) proposes to develop a system that will integrate wireless power transmission capabilities into the user"s gear and will negate the issues associated with the conventional connectors currently in use. The system will integrate the required coils and conditioning electronics into a cradle or docking station configuration that will serve to maintain coil alignment and spacing, ensuring the most efficient wireless transmission possible. BENEFIT: The benefits of the proposed system will include improved system reliability by replacing cables and connectors, with minimal additional system weight. The proposed solution will be adaptable to virtually any electronic device that can be worn by the battlefield airman. The commercial applications for the proposed technology include use by law enforcement and first responders, as well as outdoor enthusiasts, for powering or recharging multiple body-worn electronic devices from a central power supply, therefore saving on battery weight and storage space.

Agency: Department of Defense | Branch: Army | Program: SBIR | Phase: Phase I | Award Amount: 99.98K | Year: 2012

Infoscitex Corporation proposes to develop a mathematics-based predictive design tool that will greatly simplify the e-textile design process and provide designers with an extensive range of options. Our initial focus will be on garments made using broadloom e-textiles but this tool will eventually be expanded to include other textile articles and fabric types. A critical component of this effort will be the development of algorithms which are able to predict where e-textiles yarns in one pattern piece intersect with e-yarns in a second pattern piece at the seam. The IST team has already identified a promising approach for accomplishing this based on Moire fringe theory. This capability can be used to determine where along a seam a weld needs to be made, how large the welding horn needs to be in order to maximize the chance of forming a successful weld, and what other wires might be unintentionally connected. This information can in turn be used to design welding templates which will greatly simplify the garment assembly and welding process. However, the most compelling application of this tool will likely come when it is used to guide the early stages of the design process.

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