Browsing by Department "Aerospace Engineering"
Now showing items 120 of 220

A complete and fast survey of the orbital insertion design space for planetary moon missions
(20170810)The most expensive maneuver for an interplanetary spacecraft is the orbital injection. One approach to find minimum fuelcost trajectories is to preform a search over a number of design parameters such as radius of periapse, ... 
A homotopic approach to solve the fuel optimal spacecraft proximity operations problem
(201705)This report focuses on finding the lowthrust fuel optimal solution to a class of spacecraft proximity operations subject to path constraints. The mission is for a service spacecraft to perform a surveying orbit relative ... 
A simulation study towards local mass anomaly estimation using GRACE data
(20190130)Since the dawn of spaceborne Earth Science missions like the Gravity Recovery and Climate Experiment (GRACE), our understanding of global geophysical processes has increased significantly. As measurements get more precise, ... 
Acoustic waveforms produced by a laboratory scale supersonic jet
(201408)The spatial evolution of acoustic waveforms produced by a Mach 3 jet are investigated using both 1/4 inch and 1/8 inch pressure field microphones located along rays emanating from the post potential core where the peak ... 
Acoustics from highspeed jets with crackle
(201305)A scaling model based on an effective Gol'dberg number is proposed for predicting the presence of cumulative nonlinear distortions in the acoustic waveforms produced by highspeed jets. Two acoustic length scales, the shock ... 
Adaptation, gyroree stabilization, and smooth angular velocity observers for attitude tracking control applications
(201408)This dissertation addresses the problem of rigidbody attitude tracking control under three scenarios of high relevance to many aerospace guidance and control applications: adaptive attitudetracking control law development ... 
Adaptive and convergent methods for large eddy simulation of turbulent combustion
(201408)In the recent past, LES methodology has emerged as a viable tool for modeling turbulent combustion. LES computes the large scale mixing process accurately, thereby providing a better starting point for smallscale models ... 
Adaptive control for doubleintegrator class systems in the absence of velocity feedback
(201212)This work considers formulation of new classes of adaptive controllers for doubleintegrator type systems where the underlying system parameters are uncertain and the complete statevector is not available for feedback. ... 
Adaptive control schemes for systems with unknown drift and control directions
(200705)In this thesis, we consider two adaptive control problems containing unknown 2×2 or 3×3 orthogonal matrices. The first one refers to the adaptive control problem for systems with unknown drift vector directions where the ... 
Adaptive estimation and control algorithms for certain classes of largescale sensor and actuator uncertainties
(201205)This dissertation considers the general problem of controlling dynamic systems subject to largescale sensor and actuator uncertainties. The assumption is made that the uncertainty is limited to either pure rotation (i.e. ... 
Adaptive finite element simulation of flow and transport applications on parallel computers
(200705)The field of molecular and atomic sensing has seen a vast growth over the last few decades. Yet many advances still remain to be made. This dissertation takes an in depth look at the two major aspects in a molecular ... 
Alignment filtering of ICESat flight data
(201212)ICESat consisted of the Geoscience Laser Altimeter System (GLAS) and a commercial spacecraft bus. The stability of the GLAS to bus alignment was unknown and significant for GLAS pointing. Pointing control was performed by ... 
Analysis of the characteristics of grace dual oneway ranging system
(200805)The motivation for this research was an improvement of the quality of the Earth’s gravity solutions from the GRACE mission data through an instrumentlevel study. The objective was a better understanding of the characteristics ... 
An analytical approach to computing step sizes for finitedifference derivatives
(201205)Finitedifference methods for computing the derivative of a function with respect to an independent variable require knowledge of the perturbation step size for that variable. Although rules of thumb exist for determining ... 
Analytical approach to the design of optimal satellite constellations for spacebased space situational awareness applications
(201112)In recent years, the accumulation of space debris has become an increasingly pressing issue, and adequately monitoring it is a formidable task for designated groundbased sensors. Supplementing the capabilities of these ... 
Application of spontaneous Raman scattering for measurements of thermal nonequilibrium in highspeed mixing and combustion
Mixinginduced vibrational nonequilibrium is studied in the turbulent shear layer between a highspeed jet and a surrounding hotair coflow. The vibrational and rotational temperatures of N2 and O2 are determined by fitting ... 
The application of systems engineering to a Spacebased Solar Power Technology Demonstration Mission
(201205)This thesis presents an endtoend example of systems engineering through the development of a Spacebased Solar Power Satellite (SSPS) technology demonstration mission. As part of a higher education effort by NASA to ... 
Application Of The MCMC Method For The Calibration Of DSMC Parameters
(201105)A Markov Chain Monte Carlo (MCMC) algorithm was employed to obtain a calibrated distribution for the hard sphere diameter, the VHS reference diameter, and the temperature viscosity exponent of argon, for use in the Direct ... 
An architecture for incorporating interactive visualizations into scientific simulations
(200605)As scientific simulations get increasingly complex, so do the requirements of how to deal with the data that is produced. Few scientists and engineers today are satisfied with just looking at streams of numbers; we require ...