Nanosatellite Launch Data-Logger (Sync),
2018
California Polytechnic State University, San Luis Obispo
Nanosatellite Launch Data-Logger (Sync), Christopher Martin Gerdom
Master's Theses
CubeSat designers are increasingly looking to incorporate delicate structures and optics into their payloads. These delicate payloads, however, may not survive the required absolute-worst-case launch vibration testing needed for flight certification. To help address this problem, and to better match testing conditions to real-world launch environments, this thesis introduces Sync, a compact 1/4U CubeSat payload designed to collect data on the vibrations and thermal environments CubeSats experience inside a deployer on the way to orbit. This data can be used to better understand the launch environment for different vehicles, and help develop new, more realistic testing guidelines that could enable …
Hybrid Processes In Material Removal Of Hard And Brittle Materials,
2018
Western Michigan University
Hybrid Processes In Material Removal Of Hard And Brittle Materials, Hossein Mohammadi
Dissertations
New technologies demand new materials with better mechanical, optical, and thermal properties. Materials that are light weight, strong with high resistance to high temperatures, and compatible with a predetermined condition. Such materials usually are challenging to manufacture and process compared to widely available materials such as metals. Ceramics and semiconductors are considered extremely hard and brittle, making them very difficult to cut and manufacture. The other major and fast-growing type of materials are composites (including Ceramic Matrix Composites, CMC) that are also considered very challenging to machine. All these materials have many applications in major industries (i.e. electronics, aerospace, optics, …
Shape-Stabilization Of Pcm/Hdpe Composites With 3d-Printing Applications For Battery Thermal Management,
2018
Embry-Riddle Aeronautical University
Shape-Stabilization Of Pcm/Hdpe Composites With 3d-Printing Applications For Battery Thermal Management, Thomas Benjamin Freeman
Doctoral Dissertations and Master's Theses
Phase-change materials (PCMs) are a useful alternative to more traditional methods of thermal management of Li-ion batteries in electric or hybrid-electric vehicles. PCMs are materials which absorb large amounts of latent heat and undergo solid-to-liquid phase change at near-constant temperature. The goal of this thesis is to experimentally investigate the thermal properties of a novel shape-stabilized PCM/HDPE composite extruded filament. The extruded filament can then be used in a 3D printer for custom PCM/HDPE shapes. These custom PCM/HDPE shapes can be used to help reduce weight, energy consumption, and complexity of the thermal management of the ESS. The PCM used …
Design And Implementation Of Intelligent Guidance Algorithms For Uav Mission Protection,
2018
Embry-Riddle Aeronautical University
Design And Implementation Of Intelligent Guidance Algorithms For Uav Mission Protection, Karina Rivera
Doctoral Dissertations and Master's Theses
In recent years, the interest of investigating intelligent systems for Unmanned Aerial Vehicles (UAVs) have increased in popularity due to their large range of capabilities such as on-line obstacle avoidance, autonomy, search and rescue, fast prototyping and integration in the National Air Space (NAS). Many research efforts currently focus on system robustness against uncertainties but do not consider the probability of readjusting tasks based on the remaining resources to successfully complete the mission. In this thesis, an intelligent algorithm approach is proposed along with decision-making capabilities to enhance UAVs post-failure performance. This intelligent algorithm integrates a set of path planning …
Finite Element Modeling And Experimental Characterization Of Knot Configuration Effect On The Mechanical Performance Of Surgical Suture,
2018
Western Michigan University
Finite Element Modeling And Experimental Characterization Of Knot Configuration Effect On The Mechanical Performance Of Surgical Suture, Arz Y. Qwam Alden
Dissertations
Tendon injuries in orthopedic surgery and sports medicine are escalating; hence there is great interest in improving tendon repair. The integrity of tendon repair depends in part on a combination of suture material, suture size and knot configuration. Recent studies have indicated the failure of surgical knots as a failure mode during surgical repair. Further, there is still no consensus on the ideal (best/safest) surgical knot techniques. Also, this failure mode is related to stress concentrations, which cannot be easily established with traditional tensile testing. Most researchers have focused on the measurement and comparison of the gross structural response of …
Comparative Analysis Of Electrodynamic Toroidal Radiation Shielding Configurations,
2018
California Polytechnic State University, San Luis Obispo
Comparative Analysis Of Electrodynamic Toroidal Radiation Shielding Configurations, Max Rosenberg
Master's Theses
Beyond the protective confines of Earth's atmosphere and magnetosphere, spacecraft are subject to constant bombardment by high-energy charged particles originating from our Sun in the form of Solar Particle Events (SPEs), and from outside the solar system in the form of Galactic Cosmic Rays (GCRs). The harm these particles do can be reduced or mitigated outright through radiation shielding. Because protons and other charged particles comprise most of these radiation particles, strong magnetic fields could be generated around spacecraft to deflect incoming charged radiation particles. This thesis investigates the performance of specific configurations of toroidal superconducting solenoids to generate magnetic …
A Computational Fluid Dynamics (Cfd) Analysis Of The Aerodynamic Effects Of The Seams On A Two-Dimensional Representation Of A Soccer Ball,
2018
California Polytechnic State University, San Luis Obispo
A Computational Fluid Dynamics (Cfd) Analysis Of The Aerodynamic Effects Of The Seams On A Two-Dimensional Representation Of A Soccer Ball, Allen R. Rohr
Master's Theses
Most major sports today use a dedicated ball or projectile with specific shape, size, and surface geometry, except for soccer. Over the history of the sport, the surface geometry and design stayed relatively unchanged, sewn together using 32 pentagonal and hexagonal panels. However, recent innovations in panel designs differ substantially from the traditional 32 panel ball. The effects these new designs have on the aerodynamic characteristics of the ball have remained largely unknown, even with the influx of experimental research completed in the past decade. Experimental studies have been broad in scope, analyzing an entire ball in wind tunnels or …
Bi-Stability In The Wakes Of Platooning Ahmed Bodies,
2018
California Polytechnic State University, San Luis Obispo
Bi-Stability In The Wakes Of Platooning Ahmed Bodies, Daniel M. Stalters
Master's Theses
Autonomous heavy vehicles will enable the promise of decreased energy consumption through the ability to platoon in closer formation than is currently safe or legal. It is therefore increasingly important to understand the complex and dynamic wake interactions between vehicles operating in close proximity for aerodynamic gains. In recent years, a growing body of research has documented a bi-stable, shifting wake generated behind the Ahmed reference bluff body. At the same time, studies of platooning Ahmed bodies have focused on changes to the body forces and moments at different following distances or lateral offsets, typically based around time-averaged measurements or …
2018 Summer-Fall Graduate Recognition Program,
2018
The University of Alabama in Huntsville
2018 Summer-Fall Graduate Recognition Program, Propulsion Research Center, Robert Frederick
PRC Graduate Recognition
This program includes the graduate recognition program for summer and fall 2018. Includes photographs, upcoming events, recent publications, and student profiles.
Carbon Nanotube Fibers: Mechanical Behavior And The Effects Of The Space Environment,
2018
Air Force Institute of Technology
Carbon Nanotube Fibers: Mechanical Behavior And The Effects Of The Space Environment, Ryan A. Kemnitz
Theses and Dissertations
Carbon nanotube materials are promising multifunctional materials for incorporation into aerospace structures because of their high tensile strength, high electrical conductivity, and low density. This research aimed to characterize the mechanical failure mechanisms of carbon nanotube fibers and examine the effects of the space environment on their material properties. Tensile tests were conducted at varying strain rates and on fibers of varying gage lengths to examine the underlying molecular failure mechanisms and impact of defects on fiber strength. Tensile strength and elastic modulus were observed to increase with increasing strain rate and decrease with increasing gage lengths. The observed effects …
Thermal Management Of Satellite Electronics Via Gallium Phase Change Heat Sink Devices,
2018
Air Force Institute of Technology
Thermal Management Of Satellite Electronics Via Gallium Phase Change Heat Sink Devices, Brian O. Palmer
Theses and Dissertations
The purpose of this research was to determine the effectiveness and feasibility of additively manufactured heat sinks using gallium as a phase change material in the thermal management of satellite electronics. A design was created based on the footprint of an Astronautical Development, LLC Lithium 1 UHF radio and six heat sinks were additively manufactured; two each of stainless steel 316, Inconel 718, and ULTEM 9085. Each heat sink was filled with gallium for testing purposes. Models were created to simulate the behavior of the heat transfer and phase change processes occurring within the heat sink. Additionally, laboratory data was …
Flight Vehicle Design,
2018
Brigham Young University
Additively-Manufactured Hybrid Rocket Consumable Structure For Cubesat Propulsion,
2018
Utah State University
Additively-Manufactured Hybrid Rocket Consumable Structure For Cubesat Propulsion, Britany L. Chamberlain
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Three-dimensional, additive printing has emerged as an exciting new technology for the design and manufacture of small spacecraft systems. Using 3-D printed thermoplastic materials, hybrid rocket fuel grains can be printed with nearly any cross-sectional shape, and embedded cavities are easily achieved. Applying this technology to print fuel materials directly into a CubeSat frame results in an efficient, cost-effective alternative to existing CubeSat propulsion systems. Different 3-D printed materials and geometries were evaluated for their performance as propellants and as structural elements. Prototype "thrust columns" with embedded fuel ports were printed from a combination of acrylonitrile utadiene styrene (ABS) and …
Experimental Investigation Of A Green Hybrid Thruster Using A Moderately Enriched Compressed Air As The Oxidizer,
2018
Utah State University
Experimental Investigation Of A Green Hybrid Thruster Using A Moderately Enriched Compressed Air As The Oxidizer, Marc Anthony Bulcher
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
A hybrid rocket is a propulsion system that uses propellants in two different phases, typically a solid fuel inside the combustion chamber and a separate gaseous or liquid oxidizer stored in a tank. Hybrid rockets are an area of research interest because of their low explosive risk, inexpensive components, and high degree of reliability. In the Propulsion Research Laboratory at Utah State University, pure oxygen is among the top choice for hybrid rocket oxidizers due to its low cost and ease of storage. When paired with a solid fuel known as ABS (acrylonitrile butadiene styrene) plastic, specific impulse values exceed …
Autonomous Trajectory Planning For Satellite Rpo And Safety Of Flight Using Convex Optimization,
2018
Utah State University
Autonomous Trajectory Planning For Satellite Rpo And Safety Of Flight Using Convex Optimization, Nicholas G. Ortolano
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Optimal trajectory planning methods that implement convex optimization techniques are applied to the area of satellite rendezvous and proximity operations. This involves the development of linearized relative orbital motion dynamics and constraints for two satellites, where one maintains a near-circular reference orbit. The result is formulated as a convex optimization problem, where the objective is to minimize the amount of fuel required to transfer from a given initial condition to the desired final conditions. A traditional rendezvous and proximity operations scenario is analyzed, which includes examples of initial approach, inspection, final approach, and docking trajectories. This scenario may include trajectory …
Inter-Laminar Fracture Of 3d-Printed Plastics - Development Of Methods,
2018
Utah State University
Inter-Laminar Fracture Of 3d-Printed Plastics - Development Of Methods, Christopher Stolinski
All Graduate Plan B and other Reports, Spring 1920 to Spring 2023
Due to the increased use of 3D printed acrylonitrile butadiene styrene (ABS) plastic parts, a way to quantify the failure energy (energy needed to initiate cracking) is needed. Impact tests at high rates of loading are performed to determine failure energy. Throughout testing, specimens are monitored with high speed cameras to perform camera-based deformation measurements. Data acquisition and processing methods to calculate failure energy using crack opening displacement, and loading rates are developed to enable further use by Dr. Ryan Berke’s lab at Utah State University.
Design Of An Attitude Control System For A Spacecraft With Propellant Slosh Dynamics,
2018
Embry-Riddle Aeronautical University
Design Of An Attitude Control System For A Spacecraft With Propellant Slosh Dynamics, Nolan Coulter
Doctoral Dissertations and Master's Theses
The presence of propellant slosh dynamics in a spacecraft system during a maneuver leads to attitude control system (ACS) performance degradation resulting in attitude tracking errors and instability. As spacecraft missions become more complex and involve longer durations, a substantial propellant mass is required to achieve the mission objectives and perform orbital maneuvers. When the propellant tanks are only partially filled, the liquid fuel moves inside the tanks with translational and rotational accelerations generating the slosh dynamics. This research effort performs a comparative study with different optimal control techniques and a novel application of a model reference artificial immune system …
Control Driven Scaling Effects Of Motor And Rotors For Urban Air Mobility Design,
2018
Embry-Riddle Aeronautical University
Control Driven Scaling Effects Of Motor And Rotors For Urban Air Mobility Design, Agustin A. Giovagnoli
Doctoral Dissertations and Master's Theses
Through this thesis research the problem of controllability and propulsion associated with scaling-up consumer drones to vehicles that may carry significantly larger payloads, including passenger will be analyzed and tested. Controllability is mainly compromised due to the increasing response time of a larger rpm controlled rotor. This requires a more powerful motor, which translates into heavier and larger devices compromising the thrust-to-weight ratio. Collective pitch control at constant rpm is proposed as a first approach to mitigate the controllability problem, and it is tested in a MATLAB Simulink environment. This solution, linked to a Non-linear Dynamic Inversion controller, is simulated …
Variable Reluctance Virtual Torque Sensor For Automotive Applications,
2018
Western Michigan University
Variable Reluctance Virtual Torque Sensor For Automotive Applications, Vivek Iddum
Masters Theses
Torque sensing has been realized as one of the critical aspects in improving the dynamic vehicle performance in automotive systems. This thesis mainly presents the work on the development of a novel torque measurement method based on the estimation of nth-order flywheel angular acceleration from the variable reluctance flywheel speed sensor pulses. The number of firings in the engine determine the order of the harmonic to be used for torque estimation. The nth-order flywheel angular acceleration is computed using a micro-controller with built in timer counter and an associated signal conditioning circuit. The pulses obtained from the flywheel speed sensor …
Control Development For Autonomous Landing Of Quadcopter On Moving Platform,
2018
Florida Institute of Technology
Control Development For Autonomous Landing Of Quadcopter On Moving Platform, Rakhayai Mangsatabam
Theses and Dissertations
This thesis focuses on the control development for autonomous landing of a quadcopter on a moving platform. The object tracking and path following is performed through on-board vision-based systems. The goal of the thesis is to develop a controller for autonomous landing of a quadcopter and test its fidelity with simulations and experiments. The thesis is carried out in two sections, simulation and experiment. The simulation was carried out based on the system modeled and a PD (Proportional Derivative) controller was used to simulate the quadcopter landing. The simulation was split into three parts, with each part attempting to become …
