Navigation, Guidance, Control and Dynamics Commons^™

Implementation Of Path Planning Methods To Detect And Avoid Gps Signal Degradation In Urban Environments, Ayush Raminedi

Doctoral Dissertations and Master's Theses

In the modern world, various missions are being carried out under the assistance of autonomous flight vehicles due to their ability to operate in a wide range of flight conditions. Regardless, these autonomous vehicles are prone to GPS signal loss in urban environments due to obstructions that cause scintillation, multi-path, and shadowing. These effects that decrease the GPS functionality can deteriorate the accuracy of GPS positioning causing losses in signal tracking leading to a decrease in navigation performance. These effects are modeled into the simulation environment and are used as part of the path planning algorithm to provide better navigation …

Geomagnetic Aided Dead-Reckoning Navigation, Andrei Cuenca

Doctoral Dissertations and Master's Theses

The dependence of modern navigation methods on global positioning systems has led to developing alternative algorithms for localization, capable of providing reliable and robust estimations. Global position system is commonly used in a vast majority of the world’s devices, and it can supply real time position and velocity information. However, its accuracy can be compromised by external operational effects such as signal availability, cyber-attacks or weather conditions. This thesis investigates an alternative approach to enhance navigation in GPS-denied environments. Particularly, it develops an integrated navigation architecture based on geomagnetic referencing models capable of dead reckoning at GPS denied intervals. A …

Derivation And Exploration Of Analytical Aircraft Stability Analysis, Roderick Landreth

Honors Theses

A comprehensive measure of the in-flight stability of an aircraft is essential, though it can take a large amount of resources to do accurately and usefully. Small companies and colleges often don't have the resources to attain accurate experimental or analytical data to describe stable flight before potential failure. This composition investigates methods of completing a static and dynamic stability analysis for an aircraft feasible for a college, small business or hobbyist to complete, with the goal to eliminate the 'barrier of entry' concerning a lack of information and resources. A sample analytical calculation for static stability of Union College's …

Conceptual Design Of A South Pole Carrier Pigeon Uav, Kendrick M. Dlima

Master's Theses

Currently, the South Pole has a large data problem. It is estimated that 1.2 TB of data is being produced every day, but less than 500 GB of that data is being uploaded via aging satellites to researchers in other parts of the world. This requires those at the South Pole to analyze the data and carefully select the parts to send, possibly missing out on vital scientific information. The South Pole Carrier Pigeon will look to bridge this data gap.

The Carrier Pigeon will be a small unmanned aerial vehicle that will carry a 30 TB solid-state hard drive …

Simulation And Piloted Simulator Study Of An Automatic Ground Collision Avoidance System For Performance Limited Aircraft, James D. Carpenter

Theses and Dissertations

The F-16 Automatic-Ground Collision Avoidance System (Auto-GCAS) has been a resounding success since implementation in Nov 2014, saving 8 pilots and 7 aircraft from Controlled Flight into Terrain (CFIT). However, there is no implemented Auto- GCAS for "heavy" performance limited aircraft. This research endeavors to expand on the success of F-16 Auto-GCAS to other aircraft in the Air Force inventory such as the C-130, C-17, and B-1. MIL-STD-1797 classifies performance limited aircraft as large, heavy, and low to medium maneuverability. Using a stitched Learjet-25D model (LJ-25D), an Auto-GCAS algorithm was developed to predict multiple escape-maneuver trajectories, compare these paths to …

Multi-Path Automatic Ground Collision Avoidance System For Performance Limited Aircraft With Flight Tests: Project Have Medusa, Kenneth C. Gahan

Theses and Dissertations

A multi-path automatic ground collision avoidance system (Auto-GCAS) for performance limited aircraft was further developed and improved to prevent controlled flight into terrain. This research includes flight test results from the United States Test Pilot School's Test Management Project (TMP) titled Have Multi-Path Escape Decisions Using Sophisticated Algorithms (MEDUSA). Currently, the bomber and mobility air- craft communities lack an Auto-GCAS. The F-16 Auto-GCAS was proven successful for fighter-type aircraft with seven aircraft and eight lives saved from 2014 to 2018. The newly developed and tested Rapidly Selectable Escape Trajectory (RSET) sys- tem included a 5-path implementation which continuously updated at …

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) …

Design Of Shape-Conforming Nosecone For Optimal Fluid Flow From Transonic To Supersonic Range, Anna Tombazzi

Williams Honors College, Honors Research Projects

Modern flight vehicles, such as rockets, missiles, and airplanes, experience a force caused by forebody wave drag during the flight. This drag force is induced when the frontal point of each vehicle breaks the pressure wave during flight. Efforts to reduce this wave drag force to improve flight efficiency include modifying the nosecone profile of the flight vehicles to lower the drag force.

This project revolved around creating a design to make the transformation of nosecone shapes from a ¾ Parabolic profile to a ½ Power Series profile possible, mid-flight. Using a novel nosecone assembly, shape memory alloys (SMAs) and …

Real Time And High Fidelity Quadcopter Tracking System, Tyler Mckay Hall

Computer Engineering

This project was conceived as a desired to have an affordable, flexible and physically compact tracking system for high accuracy spatial and orientation tracking. Specifically, this implementation is focused on providing a low cost motion capture system for future research. It is a tool to enable the further creation of systems that would require the use of accurate placement of landing pads, payload acquires and delivery. This system will provide the quadcopter platform a coordinate system that can be used in addition to GPS.

Field research with quadcopter manufacturers, photographers, agriculture and research organizations were contact and interviewed for information …

Angle Of Attack Determination Using Inertial Navigation System Data From Flight Tests, Jack Kevin Ly

Masters Theses

Engineers and pilots rely on mechanical flow angle vanes on air data probes to determine the angle of attack of the aircraft in flight. These probes, however, are costly, come with inherent measurement errors, affect the flight characteristics of the aircraft, and are potentially dangerous in envelope expansion flights. Advances in the accuracy, usability, and affordability of inertial navigation systems allow for angle of attack to be determined accurately without direct measurement of the airflow around the aircraft. Utilizing an algorithm developed from aircraft equations of motion, a post-flight data review is completed as the first step in proving the …

The Effects Of Elevator Rate Limiting And Stick Dynamics On Longitudinal Pilot-Induced Oscillations, Patrick J. Peters

Theses and Dissertations

This report presents the results of an investigation into the effects of elevator rate limiting and stick dynamics on longitudinal pilot-induced oscillations (PIO). A simulation study was conducted to prepare for the flight test, but also to gain insight into the effects of rate limiting and stick dynamics. Due to the non-numerical nature of the simulation results, a flexible three-phase flight test plan was developed, first varying the rate limits, then varying the stick dynamics, and finally flying a matrix determined in the first two phases. There were three major conclusions. First, the offset landing task flown was insufficient to …