Engineering Commons^™

The Surface Conditions Of Spacecraft Panels May Significantly Affect Spacecraft Survivability, Trace Taylor

Research on Capitol Hill

USU junior Trace grew up in Brigham City and studies physics and electrical engineering. The majority of spacecraft failure is caused by electron charging on the outer surfaces of the craft. Additionally, contaminants on the craft can cause a film over surface panels, increasing the problem. Trace is studying how roughness on panels can mitigate this contamination as it affects the charging that can lead to craft failure. This research will help determine what optimal panel materials should be used in future spacecraft construction. Trace started research almost as soon as he came to campus in his freshman year, and …

Analysis And Design Of 3-Phase Unfolding Based Ac-Dc Battery Chargers, Rees R. Hatch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis presents the analysis and design of high-efficiency battery chargers for heavy duty EV applications. The rise in popularity of the electric vehicles (EVs) due to their increased efficiency over conventional internal combustion engines, has driven the need for more battery charging infrastructure. Furthermore, heavy duty vehicles are also being converted to electric to fill needs such as public transportation via bus fleets as well as cargo delivery via semi-trucks. Such heavy duty vehicles require more energy than personal transportation vehicles and thus require larger battery packs. To charge heavy duty battery packs in the same amount of time …

Embracing Low-Power Systems With Improvement In Security And Energy-Efficiency, Pramesh Pandey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As the economies around the world are aligning more towards usage of computing systems, the global energy demand for computing is increasing rapidly. Additionally, the boom in AI based applications and services has already invited the pervasion of specialized computing hardware architectures for AI (accelerators). A big chunk of research in the industry and academia is being focused on providing energy efficiency to all kinds of power hungry computing architectures. This dissertation adds to these efforts.

Aggressive voltage underscaling of chips is one the effective low power paradigms of providing energy efficiency. This dissertation identifies and deals with the reliability …

Raw Depth Image Enhancement Using A Neural Network, Xuan Xie

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The term image is often used to denote a data format that records information about a scene’s color. This dissertation object focuses on a similar format for recording distance information about a scene, “depth images”. Depth images have been used extensively in consumer-level applications, such as Apple’s Face ID, based on depth images for face recognition.

However, depth images suffer from low precision and high errors, and some post-processing techniques need to be utilized to improve their quality. Deep learning, or neural networks, are frameworks that use a series of hierarchically arranged nonlinear networks to process input data. Although each …

Radio-Frequency Transmitter Geolocation Using Non-Ideal Received Signal Strength Indicators, Samuel Whiting

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Locating a radio transmitter is important in a number of problems such as finding radio tags, people with radios, and devices that are collecting information in an unauthorized manner. Locating a radio transmitter is inherently difficult because the radio waves of concern are not in the visible spectrum, they reflect and distort easily, and they propagate at the speed of light.

A number of methods for locating transmitters are currently used, the majority of which require expensive hardware and extensive processing. This thesis presents a method of using simpler measurements to produce similar location estimates in order to augment or …

Digital Microfluidics As A Reconfiguration Mechanism For Antennas, Yasin Damgaci

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The properties of conventional antennas are fixed by the initial design and cannot be changed. A reconfigurable antenna, on the other hand, can dynamically change its properties, and it can adjust its behavior for a given propagation condition. This dissertation work concentrates on novel reconfiguration technologies, including design, microfabrication, and characterization aspects with an emphasis on their applications to multifunctional reconfigurable antennas. In the literature, reconfigurable antennas have made use of various reconfiguration techniques. The most common techniques utilized revolved around switching mechanisms. Other techniques such as the incorporation of variable capacitors, varactors, and physical structure manipulation surfaced recently to …

Secure Localization Topology And Methodology For A Dedicated Automated Highway System, Bhaswati Deka

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In today’s fast-paced world, mobility is a very important factor in improving the quality of living. The purpose of an automated transportation system (ATS) is to provide mobility to one and all, irrespective of their capabilities. An ATS requires a lot of planning to be efficient and safe for public use. One of the main aspects of safety is to determine the location of the individual vehicles within the system and ensure that their location is not posing any hazard to other vehicles in the system or any other entity outside the system. The process of determining or verifying the …

Development Of A Reconfigurable Multi-Faceted Communications Device Using Partial Dynamic Reconfiguration, Richard Dunkley

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Supporting a variety of communication protocols has typically required extensive hard- ware and Input/Output (I/O) interfaces targeting each protocol specifically. Recent designs in the past ten years have created more dynamic approaches by using Field Programmable Gate Arrays (FPGAs) and embedded hardware to implement or simulate previous hardware I/O designs. With the constant increase in FPGA and embedded technologies the capabilities of dynamic implementations have expanded. This report addresses the design of an up-to-date reconfigurable multi-faceted embedded device targeting recent technological advances in FPGAs.

Architecture, Inertial Navigation, And Payload Designs For Low-Cost Unmanned Aerial Vehicle-Based Personal Remote Sensing, Calvin Coopmans

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis presents work done towards a Personal Remote Sensing (PRS) system: small Unmanned Aerial Vehicles (UAVs) with electronic, control, and sensing subsystems. Based on papers presented to conferences (AutoTestCon2008 and MESA2009), as well as other work on PRS, multiple levels of engineering are detailed: complex multi-UAV data flow; attitude estimation filters; real-time microprocessor functionality; and small, mobile power systems. Wherever possible, Open-Source tools and designs have been used, modified, or studied, providing excellent cost to performance ratios in most cases. First, the overall PRS UAV architecture, AggieAir, is presented with a motivating examples (GhostEye and EagleEye camera payloads). Then, …

Micro Electro Mechanical Systems Integrated Frequency Reconfigurable Antennas For Public Safety Applications, Hema Swaroop Mopidevi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis work builds on the concept of reconfiguring the antenna properties (frequency, polarization, radiation pattern) using Radio Frequency (RF) Micro Electro Mechanical Systems (MEMS). This is a part of the overall research performed at the RF Micro/Nano Electro Mechanical Systems (μN∈MS) Laboratory at Utah State University, which includes design, microfabrication, test, and characterization of μN∈MS integrated cognitive wireless communication systems (Appendix A).

In the first step, a compact and broadband Planar Inverted F Antenna (PIFA) is designed with a goal to accommodate reconfigurability at a later stage. Then, a Frequency Reconfigurable Antenna …

Micronetworking: Reliable Communication On 3d Integrated Circuits, Andres A. Contreras

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The potential failure in through-silicon vias (TSVs) still poses a challenge in trying to extend the useful life of a 3D integrated circuit (IC). A model is proposed to mitigate the communication problem in 3D integrated circuits caused by the breaks at the TSVs. We provide the details of a low-complexity network that takes advantages of redundant TSVs to make it possible to re-route around breaks and maintain effective communication between layers. Different configurations for the micronetwork are analyzed and discussed. We also present an evaluation of the micronetwork's performance, which turns out to be quite promising, based on several …

Integrated Solar Panel Antennas For Cube Satellites, Mahmoud N. Mahmoud

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis work presents an innovative solution for small satellite antennas by integrating slot antennas and solar cells on the same panel to save small satellite surface real estate and to replace deployed wire antennas for certain operational frequencies. The two main advantages of the proposed antenna are: 1) the antenna does not require an expensive deployment mechanism that is required by dipole antennas; 2) the antenna does not occupy as much valuable surface real estate as patch antennas. The antenna design is based on using the spacing between the solar cells to etch slots in these spaces to create …

Minimum Symbol Error Rate Timing Recovery System, Nagendra Bage Jayaraj

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis presents a timing error detector (TED) used in the symbol timing synchronization subsystem for digital communications. The new timing error detector is designed to minimize the probability of symbol decision error, and it is called minimum symbol error rate TED (MSERTED). The new TED resembles the TED derived using the maximum likelihood (ML) criterion but gives rise to faster convergence relative to MLTED. The new TED requires shorter training sequences for symbol timing recovery. The TED operates on the outputs of the matched filter and estimates the timing offset. The S-curve is used as a tool for analyzing …

Cooperative Remote Sensing And Actuation Using Networked Unmanned Vehicles, Haiyang Chao

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation focuses on how to design and employ networked unmanned vehicles for remote sensing and distributed control purposes in the current information-rich world. The target scenarios are environmental or agricultural applications such as river/reservoir surveillance, wind profiling measurement, and monitoring/control of chemical leaks, etc. AggieAir, a small and low-cost unmanned aircraft system, is designed based on the remote sensing requirements from environmental monitoring missions. The state estimation problem and the advanced lateral flight controller design problem are further attacked focusing on the small unmanned aerial vehicle (UAV) platform. Then the UAV-based remote sensing problem is focused with further flight …

Transmitter Localization Using Autonomous Robotic Swarms, Joshua S. Adams

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this research is to design a proof of concept system that is capable of locating a hidden radio transmitter and to investigate methods of multi-agent formation control with a specific interest in the effectiveness of these methods on the overall objective of locating this transmitter. A system is proposed and developed in which autonomous agents work together to locate this transmitter and their responsiveness is analyzed while using formations based both on a behavioral system and a system derived from centroidal Voronoi tessellations. Many software adaptations to the existing MASnet program are required, as well as some …

Optimal Sensing And Actuation Policies For Networked Mobile Agents In A Class Of Cyber-Physical Systems, Christophe Tricaud

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The main purpose of this dissertation is to define and solve problems on optimal sensing and actuating policies in Cyber-Physical Systems (CPSs). Cyber-physical system is a term that was introduced recently to define the increasing complexity of the interactions between computational hardwares and their physical environments. The problem of designing the "cyber'' part may not be trivial but can be solved from scratch. However, the "physical'' part, usually a natural physical process, is inherently given and has to be identified in order to propose an appropriate "cyber'' part to be adopted. Therefore, one of the first steps in designing a …

Decentralized Coordination Of Multiple Autonomous Vehicles, Yongcan Cao

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation focuses on the study of decentralized coordination algorithms of multiple autonomous vehicles. Here, the term decentralized coordination is used to refer to the behavior that a group of vehicles reaches the desired group behavior via local interaction. Research is conducted towards designing and analyzing distributed coordination algorithms to achieve desired group behavior in the presence of none, one, and multiple group reference states.

Decentralized coordination in the absence of any group reference state is a very active research topic in the systems and controls society. We first focus on studying decentralized coordination problems for both single-integrator kinematics and …

Wavelets As A De-Noising Approach Of Cartilage Displacement Field Determined By Mri, David Francisco Toribio Carvajal

Undergraduate Honors Capstone Projects

Tissue engineering was once categorized as a subfield of biomaterials, but having grown in scope and importance, it can be considered as a field in its own right. Tissue engineering studies the mechanical properties of tissues and the applications that repair or replace portions of or whole tissues. The analyses of the mechanical properties of tissues can help in the diagnosis of tissue diseases and in the monitoring of the progress of tissue treatments and replacements.

In order to study the mechanical properties of tissues, it is often required to repeatedly compress and decompress the tissue. This deformation process helps …

Analog Front-End Design Using The Gm/Id Method For A Pulse-Based Plasma Impedance Probe System, Arun J. Rao

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Plasma Impedance Probe (PIP) is an electronic instrument that measures the impedance of a dipole antenna immersed in a plasma environment. Measurements made by the PIP provide valuable information regarding the plasma environment. Knowledge of ionospheric plasma density and density disturbances is required to understand radio frequency communication with satellites. The impedance curve provides us with significant plasma characteristics such as the electron-neutral collision frequency and plasma electron density.

The work proposed here is a transistor-level implementation of the analog front-end, the non-inverting amplifier that is used to drive the antenna. The antenna immersed in plasma is excited with …

A Finite Domain Constraint Approach For Placement And Routing Of Coarse-Grained Reconfigurable Architectures, Rohit Saraswat

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Scheduling, placement, and routing are important steps in Very Large Scale Integration (VLSI) design. Researchers have developed numerous techniques to solve placement and routing problems. As the complexity of Application Specific Integrated Circuits (ASICs) increased over the past decades, so did the demand for improved place and route techniques. The primary objective of these place and route approaches has typically been wirelength minimization due to its impact on signal delay and design performance. With the advent of Field Programmable Gate Arrays (FPGAs), the same place and route techniques were applied to FPGA-based design. However, traditional place and route techniques may …

Metamaterial-Inspired Miniaturized Multi-Band Microwave Filters And Power Dividers, Alper Genc

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Integration of more communication standards in one microwave wireless device created a demand on developing compact, low-cost, and robust multi-band microwave components. This dissertation presents three studies for designing miniaturized and multi-band circuits that can be used for multi-band radio frequency (RF) front-ends. These three studies are the design of dual-band and tunable bandpass filters as well as dual- and triple-band equal-split power dividers/combiners. The dual-band filter is based on split ring resonators and double slit complemantary split ring resonators. A dual-band prototype three-stage Chebyshev filter, with a fractional bandwidth of 2% at 0.9 GHz and a fractional bandwidth of …

Methodology To Derive Resource Aware Context Adaptable Architectures For Field Programmable Gate Arrays, Harikrishna Samala

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The design of a common architecture that can support multiple data-flow patterns (or contexts) embedded in complex control flow structures, in applications like multimedia processing, is particularly challenging when the target platform is a Field Programmable Gate Array (FPGA) with a heterogeneous mixture of device primitives. This thesis presents scheduling and mapping algorithms that use a novel area cost metric to generate resource aware context adaptable architectures. Results of a rigorous analysis of the methodology on multiple test cases are presented. Results are compared against published techniques and show an area savings and execution time savings of 46% each.

Native Earth Electric Field Measurements Using Small Spacecraft In Low Earth Orbit, John A. Pratt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The use of small satellites to measure the native electric field of the earth has historically presented many problems as a result of the generally modest pointing capabilities of small satellites. In spite of this, the cost of small satellites makes them ideal for just such scientific missions. This thesis details many of the constraints of electric field measuring missions as well as the requirements on any spacecraft designed to accomplish such. The data from a small sounding rocket mission is then analyzed and its usefulness discussed. Possible other methods for use are also discussed.

Design, Test, And Calibration Of The Utah State University Floating Potential Probe, Jessica D. Gregory

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The ionosphere is a conducting layer in the Earth's upper atmosphere and is the nearest naturally occurring plasma environment. Inherent to all plasma environments is an electric field. Currently, the double electric field probe is the most successful instrument for measuring the electric fields of space plasmas. Utah State University/Space Dynamics Lab has developed a double electric field probe, called the Floating Potential Probe (FPP), with a slightly different instrumentation approach than what has been done previously. The FPP is one component of a suite of instruments that launched in fall of 2007 from Wallops Island, Virginia, as part of …

Automatic People Counting And Matching, John Sallay

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis explores software algorithm for implementing a people counting and matching system to be used on a bus. A special camera is used, known as a texel camera, that generates depth and color information for a scene. This added information greatly facilitates both the tasks of matching and counting.

Although people counting is a relatively mature field, there are several situations in which current technologies are not able to count correctly. Several of these difficult situations are tested with 82% counting accuracy.

The idea of matching people on a bus is also developed. The goal is not to identify …

Object Trajectory Estimation Using Optical Flow, Shuo Liu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Object trajectory tracking is an important topic in many different areas. It is widely used in robot technology, traffic, movie industry, and others. Optical flow is a useful method in the object tracking branch and it can calculate the motion of each pixel between two frames, and thus it provides a possible way to get the trajectory of objects. There are numerous papers describing the implementation of optical flow. Some results are acceptable, but in many projects, there are limitations. In most previous applications, because the camera is usually static, it is easy to apply optical flow to identify the …

A Pipeline Analog-To-Digital Converter For A Plasma Impedance Probe, Mohamad A. El Hamoui

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Space instrumentation technology is an essential tool for rocket and satellite research, and is expected to become popular in commercial and military operations in fields such as radar, imaging, and communications. These instruments are traditionally implemented on printed circuit boards using discrete general-purpose Analog-to-Digital Converter (ADC) devices and other components. A large circuit board is not convenient for use in micro-satellite deployments, where the total payload volume is limited to roughly one cubic foot. Because micro-satellites represent a fast growing trend in satellite research and development, there is motivation to explore miniaturized custom application-specific integrated circuit (ASIC) designs to reduce …

Surface Wave Propagation In A Dielectric Waveguide Loaded With An Anisotropic, Conductive, And Spatially Dispersive Substrate, Tushar Andriyas

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis presents an analytical treatment of surface waves inside a dielectric slab loaded with a conductive and spatially dispersive semiconductor-like substrate. The work is primarily focused on the modelling of the substrate and getting the field solutions out from the Helmholtz equation. Appropriate boundary conditions have been used in order to get a unique dispersion relation. The surface wave modes are then extracted from the relation by using a root-searching algorithm, which in this work is the MATLAB Genetic Algorithm toolbox. Many different substrate configurations have been considered, starting from the very basic isotropic case to the most complex …

Full-Wave Analyses Of Nano-Electromechanical Systems Integrated Multifunctional Reconfigurable Antennas, Xiaoyan Yuan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis work builds upon the theoretical studies and full-wave analysis of radio frequency micro- and nano-electromechanical systems (RF M/NEMS) integrated multi-functional reconfigurable antennas(MRAs). This is a part of the overall μN∈MS research efforts performed in the RF NEMS Laboratory at USU, which includes design, microfabrication, test, and characterization of M/NEMS integrated congitive wireless communication systems (fig. A.1).

The thesis work focuses on two MRAs. 1) A triple bands patch antenna which can operate at 800, 2400, and 4900 MHz in response to public safety wireless communication systems. 2) A multi-frequency multi-polarization MRA for wireless personal area networking application (WPAN) …

Experiments In Distributed Multi-Robot Coordination, Larry Dale Ballard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Consensus control algorithms for multi-agent systems are an area of much research. Several consensus control laws are experimentally validated on a multi-robot testbed in this thesis. A graphical user interface (GUI) is developed that simplies use of the testbed, as well as allows the execution of the testbed programs to be divided across multiple computers. This not only provides a more powerful computing environment, but a more realistic communication environment for the testbed. A method for a time varying or dynamic formation is both proposed and experimentally validated on the testbed. This research also explores a method for dynamic group …