Browsing by Subject "Aerospace Engineering and mechanics"

Now showing 1 - 3 of 3
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    Modelling of galfenol nanowires for sensor applications.
    (2010-05) Narayan, Krishnan Shankar
    Galfenol is a new magnetostrictive material with potential applications in sensors for acoustic waves. The purpose of the present investigation is to study the properties of galfenol nanowires of nanometer range diameter relevant to sensing of acoustic waves using the phenomenon of magnetostriction. In this endeavor we study first the basic energetics for this material. Then we investigate the macro-scale behaviour for galfenol using the theory of "Large body limits in Ferro-magnetism" of Desimone [DS93]. Subsequently we look at the existence and stability of single domain states in galfenol nanowires. The theoretical predictions are then verified by numerical methods.
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    Personal navigation using a kinetic model of human gait.
    (2010-12) Matthews, Christopher J.
    Personal navigation concerns the tracking of human beings via devices carried or worn by individuals and presents a unique set of challenges in regards to navigation system and algorithm design. Many conventional position ¯xing and dead reckoning approaches tend to perform poorly given the requirements for personal navigation, which may consider GNSS-denied environments, a wide, highly dynamic range of motion, and low-cost and small form-factor sensor limitations. A novel approach to assisting or augmenting other navigation algorithms by employing a kinetic model of human gait is presented in this thesis. The kinetic model in concert with a single-axis accelerometer is shown here to comprise a virtual sensor capable of providing step size estimates in-situ for straight forward walking. Furthermore, the combination of the kinetic model and accelerometer yields a navigation solution of comparable or better performance when compared to a step counting dead reckoning approach. The derivation of this model is discussed, details of the experiments are given, and results are shown.
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    Supercavitating vehicle modeling and dynamics for control.
    (2010-05) Mokhtarzadeh, Hamid
    Abstract summary not available