Engineering Commons^™

Botsitter, Maria Hatzis, Gregory Blondheim Jr., Marian Bonto, Brett Jacobsen

Williams Honors College, Honors Research Projects

As society progresses into an era where both parents work, whether it is online or in person, children in the home may be put in dangerous situations if they are not given the attention they need. The BotSitter is an automated system that follows the child around and makes an audio alarm to alert both the child and the nearby guardian. Using RSSI trilateration, predetermined danger areas, and embedded controls, the BotSitter will be able to follow the child. The device can manage to keep track of the child for the guardian while being almost completely automated outside of setup.

Heterogeneous Multi-Sensor Fusion For 2d And 3d Pose Estimation, Hanieh Deilamsalehy

Dissertations, Master's Theses and Master's Reports

Sensor fusion is a process in which data from different sensors is combined to acquire an output that cannot be obtained from individual sensors. This dissertation first considers a 2D image level real world problem from rail industry and proposes a novel solution using sensor fusion, then proceeds further to the more complicated 3D problem of multi sensor fusion for UAV pose estimation.

One of the most important safety-related tasks in the rail industry is an early detection of defective rolling stock components. Railway wheels and wheel bearings are two components prone to damage due to their interactions with the …

Optical Spectroscopy Of Wide Bandgap Semiconductor Heterostructures And Group-Iv Alloy Quantum Dots, Tanner A. Nakagawara

Theses and Dissertations

Efficient and robust blue InGaN multiple quantum well (MQW) light emitters have become ubiquitous; however, they still have unattained theoretical potential. It is widely accepted that “localization” of carriers due to indium fluctuations theoretically enhance their efficiency by moderating defect-associated nonradiative recombination. To help develop a complete understanding of localization effects on carrier dynamics, this thesis explores degree of localization in InGaN MQWs and its dependence on well thickness and number of wells, through temperature and power dependent photoluminescence measurements. Additionally, silicon-compatible, nontoxic, colloidally synthesizable 2-5 nm Ge_1-xSn_x alloy quantum-dots (QDs) are explored for potential visible to …

Optimization Methods For Active And Passive Localization, Nil Garcia

Dissertations

Active and passive localization employing widely distributed sensors is a problem of interest in various fields. In active localization, such as in MIMO radar, transmitters emit signals that are reflected by the targets and collected by the receive sensors, whereas, in passive localization the sensors collect the signals emitted by the sources themselves. This dissertation studies optimization methods for high precision active and passive localization.

In the case of active localization, multiple transmit elements illuminate the targets from different directions. The signals emitted by the transmitters may differ in power and bandwidth. Such resources are often limited and distributed uniformly …

Localization Of Sensors In Presence Of Fading And Mobility, Hamzeh Hussain Omari

Electronic Theses and Dissertations

The objective of this dissertation is to estimate the location of a sensor through analysis of signal strengths of messages received from a collection of mobile anchors. In particular, a sensor node determines its location from distance measurements to mobile anchors of known locations. We take into account the uncertainty and fluctuation of the RSS as a result of fading and take into account the decay of the RSS which is proportional to the transmitter-receiver distance power raised to the PLE. The objective is to characterize the channel in order to derive accurate distance estimates from RSS measurements and then …

Uwb Precise Indoor Localization System Performance, Limitations And Its Integration, Essam Abdelkadir Elkhouly

Doctoral Dissertations

An indoor localization system that was built at University of Tennessee is extensively studied and improved. The goal of the system is to achieve mm down to sub-mm accuracy/precision.

Sub-sampling is used to alleviate the high sampling rate required for UWB signals. Current commercial direct sampling systems are still too slow or prohibitively expensive for UWB applications. We developed two different sub-sampling techniques, but the two systems suffer numerous shortcomings: low throughput, non-robustness, non-linearity. A third system is introduced that achieve both high accuracy and high through-put. Changes in the detection algorithm and the frame synchronization are developed to accommodate …

Global Optimization Methods For Localization In Compressive Sensing, Marco Rossi

Dissertations

The dissertation discusses compressive sensing and its applications to localization in multiple-input multiple-output (MIMO) radars. Compressive sensing is a paradigm at the intersection between signal processing and optimization. It advocates the sensing of “sparse” signals (i.e., represented using just a few terms from a basis expansion) by using a sampling rate much lower than that required by the Nyquist-Shannon sampling theorem (i.e., twice the highest frequency present in the signal of interest). Low-rate sampling reduces implementation’s constraints and translates into cost savings due to fewer measurements required. This is particularly true in localization applications when the number of measurements is …

Visual Geo-Localization And Location-Aware Image Understanding, Amir Roshan Zamir

Electronic Theses and Dissertations

Geo-localization is the problem of discovering the location where an image or video was captured. Recently, large scale geo-localization methods which are devised for ground-level imagery and employ techniques similar to image matching have attracted much interest. In these methods, given a reference dataset composed of geo-tagged images, the problem is to estimate the geo-location of a query by finding its matching reference images. In this dissertation, we address three questions central to geo-spatial analysis of ground-level imagery: 1) How to geo-localize images and videos captured at unknown locations? 2) How to refine the geo-location of already geo-tagged data? 3) …

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 …

Conductive Textiles And Their Use In Combat Wound Detection, Sensing, And Localization Applications, Stephen A. Holland

Masters Theses

Conductive textiles, originally used for electromagnetic shielding purposes, have recently been utilized in body area network applications as fabric antennas and distributed sensors used to document and analyze kinematic movement, health vital signs, or haptic interactions. This thesis investigates the potential for using conductive textiles as a distributed sensor and integrated communication system component for use in combat wound detection, sensing, and localization applications. The goal of these proof-of-concept experiments is to provide a basis for robust system development which can expedite and direct the medical response team in the field. The combat wound detection system would have the capability …

Target Localization In Passive And Active Systems : Performance Bonds, Vlad Mihai Chiriac

Dissertations

The main goal of this dissertation is to improve the understanding and to develop ways to predict the performance of localization techniques as a function of signal-to-noise ratio (SNR) and of system parameters. To this end, lower bounds on the maximum likelihood estimator (MLE) performance are studied. The Cramer-Rao lower bound (CRLB) for coherent passive localization of a near-field source is derived. It is shown through the Cramer-Rao bound that, the coherent localization systems can provide high accuracies in localization, to the order of carrier frequency of the observed signal. High accuracies come to a price of having a highly …

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 …