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.
Agency: Department of Health and Human Services | Branch: | Program: SBIR | Phase: Phase I | Award Amount: 491.40K | Year: 2012
DESCRIPTION (provided by applicant): Current treatment of many forms of congenital heart disease requires multiple surgical procedures starting shortly after birth, with attendant high morbidity and potential mortality. A promising alternative treatment calls for placing a stent in te patent ductus arteriosus (PDA), in order to delay definitive repair until the child is older and wil have a lower risk. A novel stent specifically designed for implantation in the neonate PDA is proposed, in order to overcomethe difficulties that clinicians have experienced with this new procedure in newborns, complications arising from the fact that the stents used were not designed for this purpose. An interdisciplinary team of engineers and pediatric cardiologists will (1)identify/document the requirements for a stent to be implanted in the newborn PDA, including removal; (2) perform analytical and in vitro studies with phantoms to identify the most promising candidate designs for the stent and removal instrumentation; (3)conduct an in vivo pilot study in a suitable animal model to evaluate deployment, recaptureability, trackability and radiopacity; and (4) conduct a pilot long-term animal study to assess safety and efficacy. In this latter study, proposed stent designs will be compared with stents currently being used, in regard to maintenance of patency of the PDA, tissue inflammation, and safe removal from the PDA in the presence of adherent endothelial tissue. These studies will form a compelling foundation for completing development of a PDA stent for treatment of Cyanotic Congenital Heart Disease in neonates. PUBLIC HEALTH RELEVANCE: While significant improvement in treatment of CHD has already been made, including a 30% reduction in mortality over the past decade, there is a still a long way to go and as a whole this area has been significantly underfunded. Successful development of a new stent, specifically designed for implantation in the PDA in neonates, would represent a major contribution toward this end,providing a safer and less invasive means for treating cyanotic congenital heart disease, including hypoplastic left heart syndrome (HLHS), the deadliest of all congenital heart diseases during the first year of life. Currently, the survivl of these neonates requires that they undergo invasive and highly risky open-heart procedures shortly after birth, whereas the availability of a safe and effective PDA stent for would permit delay of invasive surgery until an age when the child is at much lower risk.
Agency: Department of Defense | Branch: Army | Program: SBIR | Phase: Phase II | Award Amount: 722.57K | Year: 2012
Motion sickness is of concern in the transport of troops, be it by air, by land, or by sea. Motion sickness affects the ability to function at the peak of performance, which is particularly important for troops immersed in theatre. Despite the potential difficulties that can be incited by motion sickness, armed forces are frequently subjected to situations that can bring on motion sickness. Driving under indirect-vision driving (IVD) conditions is particularly disposed to result in motion sickness. To date the only proven methods for reducing symptoms of motion sickness are pharmacological and thus, are of limited use to armed forces. Pharmaceuticals must be taken in advance of transport, a luxury of time our troops dont always have. Moreover, they typically have associated cognitive effects which last long after transportation is completed. Our promising on-demand, non-pharmacological method of mitigating motion sickness, will be of considerable aid to our troops driving under IVD conditions, enabling them to reach destinations and complete missions without the adverse and prolonged effects of either motion sickness or traditional treatments. We completed a fully functional prototype of the system during the Phase I effort and are poised to demonstrate its efficacy in laboratory and field tests.
Agency: Department of Defense | Branch: Defense Health Program | Program: SBIR | Phase: Phase II | Award Amount: 999.88K | Year: 2012
An automated, closed loop individualized system for administration of analgesic and anesthetic medication to patients is proposed in order to ensure vigilant, optimized care, especially in special circumstances when a large number of trauma patients must be treated simultaneously by a limited number of medical personnel. The result is improved pain management, safety, outcome, and reduced complications such as post-traumatic stress disorder (PTSD). The Deployable Analgesia Administration System (DAAU) optimally sets the infusion rate and rapidly delivers an initial bolus, based on a population pharmacokinetic approach and employs feedback from vital signs monitoring and automated mental status assessment, as well as a novel means to actively query the brain to monitor analgesic/anesthetic depth, in order to safely oversee infusion. A staged product development is proposed, moving from automatic analgesia/anesthesia delivery to the conscious patient, to infusion of medication into patients whose level of consciousness is diminished either by their injuries or requirement for surgical depth of anesthesia. Phase II consists of (1) verification of biomarkers which reflect patient status and their incorporation into medication infusion algorithms, (2) construction and verification of function of a Deployable Autonomous Analgesia Unit (DAAU) prototype, (3) preclinical verification of safety of DAAU in established animal models receiving analgesia/anesthesia from the DAAU, (4) further investigation of a noninvasive sensor for monitoring analgesic/anesthetic depth (as the DAAU adjusts infusion), (5) risk management, and (6) testing to assess ease of use and setup.
Agency: Department of Health and Human Services | Branch: | Program: SBIR | Phase: Phase II | Award Amount: 1.52M | Year: 2011
DESCRIPTION (provided by applicant): Lung transplants remain the final treatment for many conditions. However, appropriate and available lungs are far fewer than the number of people who need them, leaving many patients to further deterioriate or die while waiting for a transplant. Moreover, there are many patients with insufficient lung function, including those suffering from lung cancer, who are not eligible for a lung transplant. Direct gas exchange between air and blood would provide respiratory support independent of injured lungs and allow the lungs to heal and recover. A device that can oxygenate using room air, rather than compressed air, and has a sufficiently small blood side pressure drop would greatly simplify and improve extracorporeal oxygenation. With the added requirements of long-term safety and efficacy, such a device would realize the final goal of a fully implantable artificial lung. Infoscitex has assembled a team of experts to further develop the technology for a family of vascular gasexchange devices. These devices use available room air and will likely reduce the need for anticoagulation methods compared to other devices currently available or in development. The research program detailed in this proposal will provide the necessary foundation to complete development of the technology for the implantable artificial lung, including initial animal trials. The proposed effort will result in the data necessary to secure the funding and approval for the next stage of device development andeventual market introduction. PUBLIC HEALTH RELEVANCE: The development of an implantable artificial lung based on direct vascular gas exchange performed directly from room air and requiring low levels of anticoagulation is proposed. Our device utilizes a novel two-stage gas exchange system that oxygenates blood via a liquid-liquid interface. This interface, by eliminating the contact of blood to a membrane, reduces fouling of the gas exchange surface which is the limiting factor in other devices under development.