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Full-Text Articles in Engineering
Bio-Inspired Cooperative Optimal Trajectory Planning For Autonomous Vehicles, Charles Remeikas
Bio-Inspired Cooperative Optimal Trajectory Planning For Autonomous Vehicles, Charles Remeikas
Electronic Theses and Dissertations
With the recent trend for systems to be more and more autonomous, there is a growing need for cooperative trajectory planning. Applications that can be considered as cooperative systems such as surveying, formation flight, and traffic control need a method that can rapidly produce trajectories while considering all of the constraints on the system. Currently most of the existing methods to handle cooperative control are based around either simple dynamics and/or on the assumption that all vehicles have homogeneous properties. In reality, typical autonomous systems will have heterogeneous, nonlinear dynamics while also being subject to extreme constraints on certain state …
Vision-Based Sensing And Optimal Control For Low-Cost And Small Satellite Platforms, Bradley Sease
Vision-Based Sensing And Optimal Control For Low-Cost And Small Satellite Platforms, Bradley Sease
Electronic Theses and Dissertations
Current trends in spacecraft are leading to smaller, more inexpensive options whenever possible. This shift has been primarily pursued for the opportunity to open a new frontier for technologies with a small financial obligation. Limited power, processing, pointing, and communication capabilities are all common issues which must be considered when miniaturizing systems and implementing low-cost components. This thesis addresses some of these concerns by applying two methods, in attitude estimation and control. Additionally, these methods are not restricted to only small, inexpensive satellites, but offer a benefit to large-scale spacecraft as well. First, star cameras are examined for the tendency …
Mission Analysis For Pico-Scale Satellite Based Dust Detection In Low Earth Orbits, Jacob Belli
Mission Analysis For Pico-Scale Satellite Based Dust Detection In Low Earth Orbits, Jacob Belli
Electronic Theses and Dissertations
A conceptual dust detection mission, KnightSat III, using pico-scale satellites is analyzed. The purpose of the proposed KnightSat III mission is to aid in the determination of the size, mass, distribution, and number of dust particles in low earth orbits through a low cost and flexible satellite or a formation of satellites equipped with a new dust detector. The analysis of a single satellite mission with an on-board dust detector is described; though this analysis can easily be extended to a formation of pico-scale satellites. Many design aspects of the mission are discussed, including orbit analysis, power management, attitude determination …
Mechanical Properties And Thermal Residual Stresses Of Zrb2-Sic Ceramic Composites For Hypersonic Vehicle Applications, Richard Stadelmann
Mechanical Properties And Thermal Residual Stresses Of Zrb2-Sic Ceramic Composites For Hypersonic Vehicle Applications, Richard Stadelmann
Electronic Theses and Dissertations
Ultra High Temperature Ceramic (UHTC) ZrB2- 10, 20, 30wt%SiC composites are of high interest for use in hypersonic air-breathing vehicles. In this work, ZrB2- 10, 20, 30wt%SiC UHTC composites were produced by the Spark Plasma Sintering (SPS) technique. After sintering, almost dense ceramics with ~ 5-8% porosity were produced. Their mechanical properties, such as Young’s, shear, and bulk moduli, along with Poisson’s ratio, 4-point bending strength, and single edge V-notched beam (SEVNB) fracture toughness were measured. In addition, in-situ bending experiments under a Raman microscope were performed to determine the piezo-spectroscopic coefficients of SiC Raman active peaks for calculation of …