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The Fourier Spectrum Element Method For Vibration And Power Flow Analysis Of Complex Dynamic Systems, Hongan Xu

Wayne State University Dissertations

A general numerical method, the so-called Fourier-Space Element Method (FSEM), is proposed for the vibration and power flow analyses of complex built-up structures. In a FSEM model, a complex structure is considered as a number of interconnected basic structural elements such as beams and plates. The essence of this method is to invariably express each of displacement functions as an improved Fourier series which consists of a standard Fourier cosine series plus several supplementary series/functions used to ensure and improve the uniform convergence of the series representation. Thus, the series expansions of the displacement functions and their relevant derivatives are …

Augmented Reality Navigation Interfaces Improve Human Performance In End-Effector Controlled Telerobotics, Keshav Chintamani

Wayne State University Dissertations

On the International Space Station (ISS) and space shuttles, the National Aeronautics and Space Administration (NASA) has used robotic manipulators extensively to perform payload handling and maintenance tasks. Teleoperating robots require expert skills and optimal performance is crucial to mission completion and crew safety. Degradation in performance is observed when manual control is mediated through remote camera views, resulting in poor end-effector navigation quality and extended task completion times. This thesis explores the application of three-dimensional augmented reality (AR) interfaces specifically designed to improve human performance during end-effector controlled teleoperations. A modular telerobotic test bed was developed for this purpose …

Accelerated Lattice Boltzmann Method For Colloidal Suspensions Rheology And Interface Morphology, Hassan Farhat

Wayne State University Dissertations

ABSTRACT

ACCELERATED LATTICE BOLTZMANN MODEL FOR COLLOIDAL SUSPENSIONS RHEOLOGY AND INTERFACE MORPHOLOGY

by

HASSAN FARHAT

July 2010

Advisor: Dr. Singh Trilochan

Co-Advisor: Dr. Joon Sang Lee

Major: Mechanical Engineering

Degree: Doctor of Philosophy

Colloids are ubiquitous in the food, medical, cosmetic, polymer, water purification and pharmaceutical industries. Colloids thermal, mechanical and storage properties are highly dependent on their interface morphology and their rheological behavior.

Numerical methods provide a cheap and reliable virtual laboratory for the study of colloids. However efficiency is a major concern to address when using numerical methods for practical applications.

This work introduces the main building-blocks for …

Robust Observers And Controllers For Marine Surface Vessels Undergoing Maneuvering And Course-Keeping Tasks, Nassim Khaled

Wayne State University Dissertations

The dynamic behavior of marine surface vessels is highly nonlinear. Moreover, it is significantly influenced by environmental disturbances induced by winds, random sea waves and currents. To yield a desired response of the ship, the guidance and control system of the ship should be robust to both modeling imprecision and significant environmental disturbances.

The focus of the current work is threefold. First, a six degree-of-freedom nonlinear model for a marine surface vessel is developed. It accounts for the coriolis and centripetal acceleration terms, added mass and wave damping terms, wave excitation forces, so-called "memory" effect terms, nonlinear restoring forces, wind …

Skewed Bridge Behaviors: Experimental, Analytical, And Numerical Analysis, Bang-Jo Chun

Wayne State University Dissertations

In the US, nearly 33.5% of highway bridges are skewed. In the past, these skewed bridges have been analyzed as straight bridges. Nevertheless, there exists an extensive literature indicating the mechanical behavior of skewed bridges being quite different from their straight counterparts. In this thesis, to better understand the behavior of skewed bridges, experimental, numerical, and analytical researches have been conducted. The analytical method proposed here is the first of its kind in the skewed bridge research, and is expected to aid the bridge engineers with their design.

First, a three dimensional finite element analysis (FEA) model was developed and …