21 research outputs found

    Radar/electro-optical data fusion for non-cooperative UAS sense and avoid

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    Abstract This paper focuses on hardware/software implementation and flight results relevant to a multi-sensor obstacle detection and tracking system based on radar/electro-optical (EO) data fusion. The sensing system was installed onboard an optionally piloted very light aircraft (VLA). Test flights with a single intruder plane of the same class were carried out to evaluate the level of achievable situational awareness and the capability to support autonomous collision avoidance. System architecture is presented and special emphasis is given to adopted solutions regarding real time integration of sensors and navigation measurements and high accuracy estimation of sensors alignment. On the basis of Global Positioning System (GPS) navigation data gathered simultaneously with multi-sensor tracking flight experiments, potential of radar/EO fusion is compared with standalone radar tracking. Flight results demonstrate a significant improvement of collision detection performance, mostly due to the change in angular rate estimation accuracy, and confirm data fusion effectiveness for facing EO detection issues. Relative sensors alignment, performance of the navigation unit, and cross-sensor cueing are found to be key factors to fully exploit the potential of multi-sensor architectures

    Proceedings of the Fourth MIT/ONR Workshop on Distributed Information and Decision Systems Motivated by Command-Control-Communications (C3) Problems, June 15-June 26, 1981, San Diego, California

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    "OSP number 85552"--Cover.Library has v. 2 only.Includes bibliographies.Workshop suppported by the Office of Naval Research under contract ONR/N00014-77-C-0532edited by Michael Athans ... [et al.].v.1. Surveillance and target tracking--v.2. Systems architecture and evaluation--v.3. Communication, data bases & decision support--v.4. C3 theory

    Proceedings of the 9th MIT/ONR workshop on C3 Systems, held at Naval Postgraduate School and Hilton Inn Resort Hotel, Monterey, California June 2 through June 5, 1986

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    GRSN 627729"December 1986."Includes bibliographical references and index.Sponsored by Massachusetts Institute of Technology, Laboratory for Information and Decision Systems, Cambridge, Mass., with support from the Office of Naval Research. ONR/N00014-77-C-0532(NR041-519) Sponsored in cooperation with IEEE Control Systems Society, Technical Committee on C.edited by Michael Athans, Alexander H. Levis

    An evolutionary approach to optimising neural network predictors for passive sonar target tracking

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    Object tracking is important in autonomous robotics, military applications, financial time-series forecasting, and mobile systems. In order to correctly track through clutter, algorithms which predict the next value in a time series are essential. The competence of standard machine learning techniques to create bearing prediction estimates was examined. The results show that the classification based algorithms produce more accurate estimates than the state-of-the-art statistical models. Artificial Neural Networks (ANNs) and K-Nearest Neighbour were used, demonstrating that this technique is not specific to a single classifier. [Continues.

    Relationship between Anxiety and Freezing of Gait

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    Parkinson’s disease (PD) is the second most common neurodegenerative and a large percentage of PD patients develop freezing of gait (FOG) leading to an overall reduced quality of life. The overarching aim of the thesis is to investigate the relationship between anxiety and freezing of gait, to extend current research on this topic and produce findings that could facilitate more adequate treatment methods for this symptom. The first study validated the seated functional MRI-compatible version of the walking threat paradigm that was previously found to induce anxiety and FOG. This would enable future studies to examine the neural correlates behind anxiety-induced freezing of gait. The second study investigated the effect of anxiety on the utilisation of body-related visual feedback in the form of an avatar in the virtual environment to improve FOG. The third study investigated the effects of Levodopa on the fronto-striato-limbic circuitry in PD Freezers at rest in their ‘ON’ and ‘OFF’ dopaminergic state. Findings suggest that the VR seated threat paradigm is an adequate behavioural surrogate for the VR walking threat paradigm, eliciting comparable amounts of anxiety and freezing of gait as the walking version. Anxiety was also found to interfere with the utilisation of sensory feedback to improve FOG, where in highly threatening situations Freezers lack the capacity to process visual feedback for gait. Finally, dopaminergic medication was also found to partially modulate the frontoparietal-limbic-striatal circuitry in PD Freezers, where baseline anxiety levels influence the impact of Levodopa on the frontoparietal (FPN)- limbic connectivity, and the FPN-putamen connectivity. In conclusion, the current thesis suggests that anxiety contributes to freezing of gait, which may present a barrier to treatment and could be a key factor in the heterogeneity observed in response to medication and sensory cueing

    Autonomous agents for multi-function radar resource management

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    The multifunction radar, aided by advances in electronically steered phased array technology, is capable of supporting numerous, differing and potentially conflicting tasks. However, the full potential of the radar system is only realised through its ability to automatically manage and configure the finite resource it has available. This thesis details the novel application of agent systems to this multifunction radar resource management problem. Agent systems are computational societies where the synergy of local interactions between agents produces emergent, global desirable behaviour. In this thesis the measures and models which can be used to allocate radar resource is explored; this choice of objective function is crucial as it determines which attribute is allocated resource and consequently constitutes a description of the problem to be solved. A variety of task specific and information theoretic measures are derived and compared. It is shown that by utilising as wide a variety of measures and models as possible the radar’s multifunction capability is enhanced. An agent based radar resource manager is developed using the JADE Framework which is used to apply the sequential first price auction and continuous double auctions to the multifunction radar resource management problem. The application of the sequential first price auction leads to the development of the Sequential First Price Auction Resource Management algorithm from which numerous novel conclusions on radar resource management algorithm design are drawn. The application of the continuous double auction leads to the development of the Continuous Double Auction Parameter Selection (CDAPS) algorithm. The CDAPS algorithm improves the current state of the art by producing an improved allocation with low computational burden. The algorithm is shown to give worthwhile improvements in task performance over a conventional rule based approach for the tracking and surveillance functions as well as exhibiting graceful degradation and adaptation to a dynamic environment

    Data bases and data base systems related to NASA's aerospace program. A bibliography with indexes

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    This bibliography lists 1778 reports, articles, and other documents introduced into the NASA scientific and technical information system, 1975 through 1980

    Aeronautical Engineering: A continuing bibliography with indexes (supplement 175)

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    This bibliography lists 467 reports, articles and other documents introduced into the NASA scientific and technical information system in May 1984. Topics cover varied aspects of aeronautical engineering, geoscience, physics, astronomy, computer science, and support facilities

    Advanced Sensing and Control for Connected and Automated Vehicles

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    Connected and automated vehicles (CAVs) are a transformative technology that is expected to change and improve the safety and efficiency of mobility. As the main functional components of CAVs, advanced sensing technologies and control algorithms, which gather environmental information, process data, and control vehicle motion, are of great importance. The development of novel sensing technologies for CAVs has become a hotspot in recent years. Thanks to improved sensing technologies, CAVs are able to interpret sensory information to further detect obstacles, localize their positions, navigate themselves, and interact with other surrounding vehicles in the dynamic environment. Furthermore, leveraging computer vision and other sensing methods, in-cabin humans’ body activities, facial emotions, and even mental states can also be recognized. Therefore, the aim of this Special Issue has been to gather contributions that illustrate the interest in the sensing and control of CAVs
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