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A novel Eigenstructure Assignment (ESA) method for vibration confinement of flexible structures has been developed. This method is an output feedback control and determines the closed-loop systems that their eigenvectors are orthogonalized to the open-loop eigenvectors. This method is a numerical method and used Singular Value Decomposition (SVD) to find(More)
(ABSTRACT) This dissertation addresses the problem of motion planning and control for nonholonomic mobile robots, particularly wheeled and tracked mobile robots, working in extreme environments, for example, desert, forest, and mine. In such environments, the mobile robots are highly subject to external disturbances (e.g., slippery terrain, dusty air,(More)
Mechanical Engineering This study evaluates the dynamic interaction between rail vehicles and the track on which they travel. The measurements were analyzed in the time and frequency domain. The effects of external parameters such as the vehicle design, subgrade stiffness, and degree of curvature were analyzed and compared for both the vehicle response and(More)
This work deals with the biocompatibility of dense nano- and micro-structured Hydroxyapatite/Titania composites prepared by two step and conventional sintering, respectively. By application of two step sintering, it was shown that the final grain size of HA-15 wt.% TiO2 is maintained lower than 100 nm while by the application of conventional sintering it(More)
This study explores the use of generalized polynomial chaos theory for modeling complex nonlinear multibody dynamic systems in the presence of parametric and external uncertainty. The polynomial chaos framework has been chosen because it offers an efficient computational approach for the large, nonlinear multibody models of engineering systems of interest,(More)
This study applies generalized polynomial chaos theory to model complex nonlinear multibody dynamic systems operating in the presence of parametric and external uncertainty. Theoretical and computational aspects of this methodology are discussed in the companion paper " Modeling Multibody Dynamic Systems With Uncertainties. Part I: Theoretical and(More)
In this paper a nonlinear stress-based controller is designed to position a single-degree-of-freedom shape memory alloy (SMA) actuated manipulator. A three-part model was constructed based on the dynamics/kinematics of the arm, the thermomechanical behavior of SMAs, and an assumed heat transfer model consisting of electrical heating and natural convection.(More)
Orthogonal eigenstructure control is a novel active control method for vibration suppression in multi-input multi-output linear systems. This method is based on finding an output feedback control gain matrix in such a way that the closed-loop eigenvectors are almost orthogonal to the open-loop ones. Singular value decomposition is used to find the matrix,(More)
Disturbed sleep is common in end-stage renal disease (ESRD). Exogenous melatonin has somniferous properties in normal subjects and can improve sleep quality (SQ) in several clinical conditions. Recent studies have shown that melatonin may play a role in improving sleep in patients undergoing dialysis. The goal of the present study was to assess the effect(More)
The accuracy of the results from a rail vehicle dynamic model is dependent on the realism of the track input to the model. An important part of the track input is the irregularities that exist on actual track. This study analyzes the irregularities inherent in railroad track geometry data, and provides an analytical method for creating track data with the(More)