Engineering Commons^™

Advancing Near Surface Soil Moisture Measurements Using Robotics, Automation, And Remote Sensing, Hemanth Narayan Dakshinamurthy

All Graduate Theses and Dissertations, Fall 2023 to Present

Near-surface soil moisture, or the water content within the soil, is important for understanding the interactions between land and the atmosphere, and for monitoring plants in agricultural settings. However, soil moisture can be highly variable within the same field and varies considerably with time. The challenge involved with measuring soil moisture is that traditional techniques that rely on obtaining large samples are labor and time-intensive, especially for large fields. Developments in sensor technologies have allowed users to record the soil moisture regularly at the points where the sensors are installed. However, to understand how soil moisture changes across a field …

Estimated Aerodynamic Forces And Moments And Optimal Orientation Of The V-Bat Airframe During Vertical Landing In Gusty Conditions, Parker C. Carter

All Graduate Theses and Dissertations, Fall 2023 to Present

Ship based Unmanned Air Systems (UAS) are an important tool used by the United States Navy for situational awareness and short-range operations. Naval UAS are used to provide real-time intelligence, surveillance, reconnaissance, and target-acquisition while being low cost, mission flexible, and safe. Unfortunately UAS suffer disadvantages with respect to adverse environmental conditions caused by the air being displaced by the ship. The accumulation of one or more adverse conditions is known as airwake. To counteract the effects of airwake, the objectives of this work are to first evaluate the effect of forces and moments during the vertical landing phase of …

Sensitivity Study For Uav Gps-Denied Navigation In Uncertain Landmark Fields, Samantha D. Burton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This document provides two 2D simulation sensitivity analyses regarding a drone’s flight characteristic (state) errors within a GPS-denied region. The research focuses on a development and investigation of utilizing a camera to simultaneously determine a drone’s state while locating landmarks, where there is uncertainty in the landmarks’ exact positions prior to the mission (SLAM). This SLAM method is performed in regions with limited access to GPS. Furthermore, there is development and investigation of controlling the drone in conjunction with SLAM using potential error-reducing control parameters. Objectives are to quantitatively understand the UAV’s sensitivity of position errors to sensor grade and …

Improvement Opportunities In The Two-Source Energy Balance Model For Et Using Uav Imagery And Point Cloud Information, Mahyar Aboutalebi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In recent years, satellites and unmanned aerial vehicles (UAVs) provide enormous amounts of spatially-distributed information for monitoring crop conditions by measuring crop’s reflected and emitted radiation at a distance. However, applications of high-resolution UAV imagery and its intermediate products for improving crop water use estimates are not well studied. In other words, the available approaches, methods and algorithms for determining how much water to apply for irrigation using remotely sensed data have been mostly developed at satellite spatial resolutions. High-resolution imageries that have been achieved by small UAVs open new opportunities for revisiting, re-evaluating, and revising available crop water use …

Self-Describing Fiducials For Gps-Denied Navigation Of Unmanned Aerial Vehicles, Amanda J. Strate

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Accurate estimation of an Unmanned Aerial Vehicle’s (UAV’s) location is critical for the operation of the UAV when it is controlled completely by its onboard processor. This can be particularly challenging in environments in which GPS is not available (GPS-denied). Many of the options previously explored for estimation of a UAV’s location without the use of GPS require more sophisticated processors than can feasibly be mounted on a UAV because of weight, size, and power restrictions. Many options are also aimed at indoor operation without the range capabilities to scale to outdoor operations. This research explores an alternative method of …

Evaluating The Hydraulic Performance Of Digital Photogrammetry-Derived 3-Dimensional Models Of A Hydraulic Structure Using Computational Fluid Dynamics, Tyler J. Ashby

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research investigated the combination of aerial imagery, photogrammetry, and computational fluid dynamics (CFD). Two 3D models of an 8-ft ramp flume were developed from aerial imagery using a commercial photogrammetry software. The GCP model was developed using ground control points (GCP) to improve and measure the model's accuracy. The Non-GCP model used GCPs as check points, which only measure the model's accuracy. The horizontal and vertical errors were, respectively, 0.39 in. and 0.73 in. for the GCP model, and 5.37 in. and 2.80 in. for the Non-GCP model.

In addition to the GCP and Non-GCP models, two hybrid 3D …

System-Level Analysis Of Autonomous Uav Landing Sensitivities In Gps-Denied Environments, Terran R. Gerratt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This paper presents an analysis of the navigation accuracy of an fixed-wing Unmanned Aerial Vehicle (UAV) landing on a aircraft carrier. The UAV is equipped with typical sensors used in landing scenarios. Data from the Office of Naval Research is used to accurately capture the behavior of the aircraft carrier. Through simulation, the position and orientation of both the UAV and carrier are estimated. The quality of the UAV’s sensors are varied to determine the sensitivity of these estimates to sensor accuracy. The system’s sensitivity to GPS signals and visual markers on the carrier is also analyzed. These results allow …

Robust Resource Allocation To Secure Physical Layer Using Uav-Assisted Mobile Relay Communications In 5g Technology, Shakil Ahmed

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The unmanned aerial vehicles (UAVs) are also known as drones. Recently, UAVs have attracted the next generation researchers due to their flexible, dynamic, and cost-effective deployment, etc. Moreover, the UAVs have a wide range of application domains, such as rescue operation in the remote area, military surveillance, emergency application, etc. Given the UAVs are appropriately deployed, the UAVs provide continuous and reliable connectivity, on-demand, and cost-effective features to the desired destination in the wireless communication system. Thus, the UAVs can be a great choice to deploy as a mobile relay in co-existence with the base stations (BSs) on the ground …

An Experimental Comparison Of Student Motivation Between Two Computational Thinking-Based Stem Activities: Vex-Based Automation And Robotics And A Quadcopter Activity, Cory J. Ortiz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to compare student motivation between two junior high level computational thinking based STEM curricular activities. These two activities were a newly developed quadcopter based curriculum and a VEX based curricular activity developed for Project Lead the Way’s Gateway to Technology – Automation and Robotics course. Student motivation was assessed using an assessment called My Class Activities which broke motivation into four constructs: interest, challenge, choice, and enjoyment.

This study assessed students in three schools in a northern Utah school district. Students were assessed after receiving each curriculum. Assessment responses were then coded and analyzed. …

Path Following By A Quadrotor Using Virtual Target Pursuit Guidance, Abhishek Manjunath

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Missile guidance laws have been solely developed to follow and intercept a target thereby destroying or damaging it. In this research, the primary objective is to modify and adopt a missile guidance law to be used on a quadrotor to follow a virtual target. The target is termed 'virtual' as it only exists mathematically in the form of equations. The goal is to have the quadrotor successfully following the predefined path (described by the target) while maintaining a fixed distance from the virtual target. To ensure viability and assess performance, a detailed comparison with another path following law is made.

Cognitive Formation Flight In Multi-Unmanned Aerial Vehicle-Based Personal Remote Sensing Systems, Long Di

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This work introduces a design and implementation of using multiple unmanned aerial vehicles (UAVs) to achieve cooperative formation flight based on the personal remote sensing platforms developed by the author and the colleagues in the Center for Self-Organizing and Intelligent Systems (CSOIS). The main research objective is to simulate the multiple UAV system, design a multi-agent controller to achieve simulated formation flight with formation reconfiguration and real-time controller tuning functions, implement the control system on actual UAV platforms and demonstrate the control strategy and various formation scenarios in practical flight tests. Research combines analysis on flight control stabilities, develop- ment …

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 …

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 …