Navigation, Guidance, Control and Dynamics Commons^™

Farmer Perceptions Of Land Cover Classification Of Uas Imagery Of Coffee Agroecosystems In Puerto Rico, Jose Cabrera, Blake Neal, Kevin Adkins, Ronny Schroeder, Gwendolyn Klenke, Shannon Brines, Nayethzi Hernandez, Kevin Li, Riley Glancy, Ivette Perfecto

Publications

Highly diverse agroecosystems are increasingly of interest as the realization of farms’ invaluable ecosystem services grows. Simultaneously there has been an increased use of uncrewed aerial systems (UAS) in remote sensing as drones offer a finer spatial resolution and faster revisit rate than traditional satellites. With the combined utility of UAS and the attention on agroecosystems, there exists an opportunity to assess UAS practicality in highly biodiverse settings. In this study, we utilized UAS to collect fine-resolution 10-band multispectral imagery of coffee agroecosystems in Puerto Rico. We created land cover maps through a pixel-based supervised classification of each farm and …

Uas Model Identification And Simulation To Support In-Flight Testing Of Discrete Adaptive Fault-Tolerant Control Laws, Mansi Subhash Bakori

Doctoral Dissertations and Master's Theses

In mission-critical applications of unmanned and autonomous aerial systems(UAS), it is of significant importance to develop robust strategies for fault-tolerant systems that can countermeasure system degradation and consequently support the integration into the National Airspace (NAS). This thesis research illustrates the results of systems identification that is performed using DATCOM followed by the flight test data. This data is acquired from conducting an intensive flight testings program of a fixed-wing UAS to determine the state-space model of the aircraft. A discrete state-space system is reconstructed from these models to derive Auto-Regressive Moving-Average (ARMA) models used to design a Discrete Direct …

Three-Dimensional, Vision-Based Proportional Navigation For Uav Collision Avoidance, Guanhong Gao

Doctoral Dissertations and Master's Theses

As the number of potential applications for Unmanned Aerial Vehicles (UAVs) keeps rising steadily, the chances that these devices will operate in close proximity to static or dynamic obstacles also increases. Therefore, collision avoidance is an important challenge to overcome for Unmanned Aerial Vehicle operations. Electro-optical devices have several advantages such as light weight, low cost, low algorithm requirements with respect to computational power and possibly night vision capabilities. Therefore, vision-based Unmanned Aerial Vehicle collision avoidance has received considerable attention. Although much progress has been made in collision avoidance systems (CAS), most approaches are focused on two-dimensional environments. In order …

Uncover The Power Of Multipath : Detecting Nlos Drones Using Low-Cost Wifi Devices, Ashok Vardhan Raja

Doctoral Dissertations and Master's Theses

In recent years, consumer UAV technology has seen considerable advances. Consumer UAVs have become an ideal vector for privacy invasions due to their affordability, size, maneuverability, and their ability to stream live high-quality video. There is considerable proliferation of drones in both civil and military domains. Hence it is critical to detect invading unmanned aerial vehicles (UAVs) or drones in a timely manner for both security and safeguarding privacy. Currently available solutions like active radar, video or acoustic sensors are very expensive (especially for individuals) and have considerable constraints (e.g., requiring visual line of sight).

Recent research on drone detection …

Evaluation Of Unmanned Aircraft Flying Qualities Using A Stitched Learjet Model, Patrick M. Callaghan

Theses and Dissertations

In recent years, military UAVs have taken over missions that were too dull, dirty, or dangerous for manned aircraft. The increased demand has led to a build-fly-fix-fly development mentality, plaguing the early lifecycle with staggering mishap rates. Currently, MIL-STD-1797 lists flying qualities for UAVs as TBD, and the standards for manned fixed wing are inadequate when applied to UAVs. In an effort to expand the database of UAV flying qualities, an analysis was completed on a Simulink model of an LJ-25D developed from Calspans Variable Stability System aircraft at the United States Test Pilot School. Three maneuvers were simulated: (1) …

Vision-Aided Navigation Using Tracked Landmarks, Nicodemus Myhre

Doctoral Dissertations and Master's Theses

This thesis presents vision-based state estimation algorithms for autonomous vehicles to navigate within GPS-denied environments. To accomplish this objective, an approach is developed that utilizes a priori information about the environment. In particular, the algorithm leverages recognizable ‘landmarks’ in the environment, the positions of which are known in advance, to stabilize the state estimate. Measurements of the position of one or more landmarks in the image plane of a monocular camera are then filtered using an extended Kalman filter (EKF) with data from a traditional inertial measurement unit (IMU) consisting of accelerometers and rate gyros to produce the state estimate. …

Design Of Synthetic Jet Actuator For Flight Control Of Small Uav, Priyanka Pagadala

Doctoral Dissertations and Master's Theses

The main idea of this project is to develop a prototype SJA - Synthetic Jet Actuator to embed into a small UAV with modified Glauert wing cross-section for Active Flow Control. Apart from lift enhancement, drag reduction, or separation control, etc; LCO suppression might be possible by modifying the boundary layer through the use of these actuators. For initial investigation, a wing section with span of 12.4 cm and chord of 14 cm was fabricated and tests were conducted in the subsonic wind tunnel at the free stream velocities of 5 and 10 m / s. From these experiments, lift …

Thinking Rather Than Panicking About The Current Drone Threat, Tom Foley, Tyrone Groh

Aviation / Aeronautics / Aerospace International Research Conference

Originally titled "UAS Threats in Sport Venues," the authors opted to expand their focus to better to all threats from UASs, and to encourage better preparation for and responses to such threats. Foley and Groh discuss different strategies.

Adaptive Control For Autonomous Navigation Of Mobile Robots Considering Time Delay And Uncertainty, Stephen Kofi Armah

Dissertations

Autonomous control of mobile robots has attracted considerable attention of researchers in the areas of robotics and autonomous systems during the past decades. One of the goals in the field of mobile robotics is development of platforms that robustly operate in given, partially unknown, or unpredictable environments and offer desired services to humans. Autonomous mobile robots need to be equipped with effective, robust and/or adaptive, navigation control systems. In spite of enormous reported work on autonomous navigation control systems for mobile robots, achieving the goal above is still an open problem. Robustness and reliability of the controlled system can always …

Formation Feedback Control Of Uav Flight, Stephen Stegall

Doctoral Dissertations and Master's Theses

This thesis is a study of formation control with autonomous unmanned aerial vehicles using the formation as feedback. There is also an investigation of formation methods presenting insight into different algorithms for formations. A rigid formation is achieved using a proportional-derivative virtual structure with a formation feedback controller. There is an emphasis on stick controlled aerodynamics. The rigid formation is verified by a simulation of a longitudinal model. Formation control ideas are presented for rigid formations.