Space Vehicles Commons^™

Waste And Duplication In Nasa Programs: The Need To Enhance U.S. Space Program Efficiency, Bert Chapman

Libraries Faculty and Staff Scholarship and Research

The U.S. Government faces acute budgetary deficits and national debt problems in the Obama Administration. These problems have been brought about by decades of unsustainable government spending affecting all agencies including the National Aeronautics and Space Administration. (NASA). An outgrowth of this fiscal profligacy is the presence of wasteful and duplicative programs within NASA that prevent this agency from achieving its space science and human spaceflight objectives. These problems occur due to mismanagement of these programs from NASA and the creation of these programs by the U.S. Congress and congressional committees. This occurs because congressional appropriators tend to be more …

Energy Use & Generation, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professor Bob Twiggs on "Energy Use & Generation" from January 19, 2015.

Suborbital Spaceflight: A Student Team’S Plan To Send A Rocket To Space, Bryce Chanes, William Carpenter, Julio Benavides, Matthew Haslam, Brenda Haven

Aviation / Aeronautics / Aerospace International Research Conference

The Eagle Space Flight Team was created with the goal of becoming the first undergraduate team to design, build, and launch a rocket capable of suborbital spaceflight. In order to achieve this goal, the team will have to design a rocket capable of atmospheric flight at speeds over Mach 5 and launch it on one of the largest amateur rocket motors ever made. Over the next three years, the team will progress towards accomplishing this feat through a series of incremental test flights. Before the space flight, the team will build three sub-scale rockets designed to reach altitudes of 30,000’, …

Numerical Investigation On Charring Ablator Geometric Effects: Study Of Stardust Sample Return Capsule Heat Shield, Haoyue Weng, Alexandre Martin

Mechanical Engineering Faculty Publications

Sample geometry is very influential in small charring ablative articles where 1D assumption might not be accurate. In heat shield design, 1D is often assumed since the nose radius is much larger than the thickness of charring. Whether the 1D assumption is valid for the heat shield is unknown. Therefore, the geometric effects of Stardust sample return capsule heat shield are numerically studied using a material response program. The developed computer program models material charring, conductive heat transfer, surface energy balance, pyrolysis gas transport and orthotropic material properties in 3D Cartesian coordinates. Simulation results show that the centerline temperatures predicted …

Deposition Thickness Modeling And Parameter Identification For Spray Assisted Vacuum Filtration Process In Additive Manufacturing, August Mark

Electronic Theses and Dissertations

To enhance mechanical and/or electrical properties of composite materials used in additive manufacturing, nanoparticles are often time deposited to form nanocomposite layers. To customize the mechanical and/or electrical properties, the thickness of such nanocomposite layers must be precisely controlled. A thickness model of filter cakes created through a spray assisted vacuum filtration is presented in this paper, to enable the development of advanced thickness controllers. The mass transfer dynamics in the spray atomization and vacuum filtration are studied for the mass of solid particles and mass of water in differential areas, and then the thickness of a filter cake is …

Nusat I Participant Photographs, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professor Bob Twiggs of the participants involved with the NUSat I program from January 3, 2013.

Cubesat Remote Data & Comms Transponders 145.825 Mhz, Bob Bruninga, Mirek Kasal, Mike Ruprecht

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint presentation created by Bob Bruninga, Mirek Kasal, and Mike Ruprecht titled "Cubesat Remote Data & Comms Transponders 145.825 MHz" from October 16, 2015.

Cubesat Wakes In The Earth’S Ionosphere, Robert M. Albarran Ii

Doctoral Dissertations and Master's Theses

Space exploration is currently being revolutionized by the advent of the CubeSat: 10cm cubed satellites that typically deploy in constellations for less than $100,000. Spacecraft instrumentation design must be redefined to abide by the compact CubeSat payload. Furthermore, the CubeSat dimension must be considered with respect to characteristic length scales of the space plasma environment, namely, the Debye length. Although spacecraft-plasma interactions- surface charging, plasma sheaths and wakes- have been well-studied for larger satellites, they are less understood for CubeSats.

The Dynamic Ionosphere CubeSat Experiment (DICE) is a 1.5U CubeSat which recently ended its mission. DICE carried two fixed-bias Langmuir …

An Unstandard Way Of Using The Cubesat Standard, Robert J. Twiggs, Amin Djamshidpour, Steward Davis, Ben Malphrus

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint presentation created by Professor Bob Twiggs, Amin Djamshidpour, Steward Davis, and Ben Malphrus titled  "An Unstandard way of Using the CubeSat Standard" from November 8, 2014.

Space Hackathon: Magnitude.Io, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint presentation created by Professor Bob Twiggs titled "Space Hackathon: Magnitude.io" from November 7, 2014.

Understanding Orbits: Chapters 4-9, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professor Bob Twiggs titled "Understanding Orbits: Chapters 4-9" from October 30, 2014.

Dynamic Simulation Of Aerial Trolley Alternative To The Mighty Eagle, Jerry Sweafford

Von Braun Symposium Student Posters

No abstract provided.

Control Of A Fuel Cell Based Autonomous Electric Power System For An Aerospace Vehicle, Roshini S. Ashok

Von Braun Symposium Student Posters

No abstract provided.

High Powered Composite Payload Fairing Rocket For Deployable Robotics, Markus Murdy

Von Braun Symposium Student Posters

No abstract provided.

Spacebird: Promoting Space Exploration Through Space Tourism, Eléonore Fontanges

Von Braun Symposium Student Posters

No abstract provided.

Improving And Expanding The Capabilities Of The Poly-Picosatellite Orbital Deployer, David Pignatelli

Master's Theses

The Poly-Picosatellite Orbital Deployer (P-POD) has undergone a series of revisions over the years. The latest revision, described in this Master’s Thesis, incorporates new capabilities like EMI shielding, an inert gas purge system, and an electrical interface to the CubeSats after they are integrated into the P-POD. Additionally, some mass reduction modifications are made to the P-POD, while its overall strength is increased. The P-POD inert gas purge system successfully flew, on a previous revision P-POD. The P-POD components are analyzed to a set of dynamic loads for qualification, and successfully undergoes random vibration qualification testing. The P-POD encounters some …

Design Improvements For A Reusable Horizontal Takeoff And Landing Aircraft For Use On Mars, Brian A. Skoog

Mechanical & Aerospace Engineering Theses & Dissertations

Unmanned aerial vehicle capabilities are required for expanded exploration of the Martian surface. These vehicles can not only gather data at an altitude otherwise unreachable by rovers and satellites, but also deliver small payloads and retrieve samples from distant off-site locations. Previous multi-purpose reusable Mars aircraft studies have been unable to achieve the flight ranges required for expanded exploration. This study has focused on increasing the range of prototype aircraft designs. Assuming that large precision cargo delivery capabilities have been developed and much of the infrastructure associated with a fixed Mars base is in place, the challenge of linking dispersed …

Cubesats: The Beginning Of Amateur Space Exploration, Tim Debenedictis

Robert "Bob" Twiggs STEM Education Collection

An article by Tim DeBenedictis of the Southern Stars Group titled "CubeSats: the Beginning of Amateur Space Exploration" from August 7, 2014.

Microthruster Fabrication And Characterization: In Search Of The Optimal Nozzle Geometry For Microscale Rocket Engines, Katherine L. Fowee, Alina Alexeenko

The Summer Undergraduate Research Fellowship (SURF) Symposium

A major consideration in microsatellite design is the engineering of micropropulsion systems that can deliver the required thrust efficiently with tight restrictions on space, weight, and power. Cold gas thrusters are one solution to the demand for smaller propulsion systems to accommodate the advancements in technology that have allowed for a reduction in the size and thus the cost of satellites. While much research has been done in understanding the flow regimes within these microthrusters, there is a need to understand how different nozzle designs affect microthruster performance. This requires that experimental data be collected on varying nozzles shapes (orifices, …

Trajectory Optimization For A Misson To The Trojan Asteroids, Shivaji Senapati Gadsing

Masters Theses

The problem of finding a minimum-fuel trajectory for a mission to the Jovian Trojan asteroids is considered. The problem is formulated as a modified traveling salesman problem. Two different types of algorithms such as an exhaustive search algorithm and a serial rendezvous search algorithm are developed. The General Mission Analysis Tool (GMAT) is employed for finding optimum trajectories with minimal fuel consumption. The selection of a minimum-fuel mission trajectory, and the associated target asteroids, will be a key factor in determining feasibility and scientific value of a Trojan tour and rendezvous mission.

The transfer trajectory followed by a spacecraft between …

The Study Of Electrostatic And Magnetostatic Active Space Radiation Shielding For Deep Space Missions, Leroy A. Fung

Electrical & Computer Engineering Theses & Dissertations

A goal of the National Aeronautics and Space Administration (NASA) has been to develop technologies that will enable deep space explorations. Such missions include a prolonged stay on the Moon and the ability to sustain a long duration of travel time to Mars and beyond. Long-term human exposures to radiation are a crucial concern. Recent research has taken focus on active and passive shielding methods as a way of eliminating the hazard posed by radiation particles. Passive shielding involves the use of materials that has the ability to withstand radiation particles and reduce the dose by stopping or slowing the …

Numerical Study Of Spallation Phenomenon In An Arc-Jet Environment, Raghava Davuluri, Alexandre Martin

Mechanical Engineering Faculty Publications

The spallation phenomenon might affect the aerodynamic heating rates of re-entry vehicles. To investigate spallation effects, a code is developed to compute the dynamics of spalled particles. The code uses a finite-rate chemistry model to study the chemical interactions of the particles with the flow field. The spallation code is one-way coupled to a CFD solver that models the hypersonic flow field around an ablative sample. Spalled particles behavior is numerically studied for argon and air flow field. The chemistry model is compared with that of Park's model which complies with oxidation and sublimation and shows disagreement for nitridation.

Space Environment, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professor Bob Twiggs titled "Space Environment" from May 12, 2014.

Context & Overview, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professor Bob Twiggs titled "Context & Overview" from May 12, 2014.

Earth Orbits, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professor Bob Twiggs titled "Earth Orbits" from May 12, 2014.

The Next Big Thing Is Small, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professor Bob Twiggs titled "The Next Big Thing is Small" from May 8, 2014.

The Effect Of The 2-Dimensional Magnetic Field Profile In Hall Thrusters, Megan Lewis Harvey

Doctoral Dissertations and Master's Theses

Electric propulsion engines, in particular Hall thrusters, provide the possibility of long-distance, low-cost space travel. The geometrical details of the Hall thrusters, especially the magnetic field prole, are crucial to improving their efficiency. The effect of the magnetic field structure was investigated using a simple, two-dimensional model, assuming axial symmetry. The previous one-dimensional conclusion, namely that the details of the shape of the magnetic field are unimportant, was confirmed. This result has implications for the design of future Hall thruster engines, with an eye toward maximizing their efficiency.

The Pocketqube Concept, Robert J. Twiggs, J. G. Jernigan, L. R. Cominsky, L. R. Malphrus, B. K. Silverman, K. Zack, S. Mcneil, W. Roach-Barrett, T-Logoqube

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professor Bob Twiggs and associates titled "The PocketQube Concept" from April 23, 2014.

Innovative Uses Of The Canisterized Satellite Dispenser (Csd), Robert J. Twiggs, Walter Holemans, Ryan Williams, Andrew Kalman, Rex Ridenoure, Tom Walkinshaw, Ryan Hevner, Floyd Azure

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Walter Holemans, Ryan Williams, Andrew Kalman, Robert Twiggs, Rex Ridenoure, Tom Walkinshaw, Ryan Hevner, and Floyd Azure titled "Innovative Uses of the Canisterized Satellite Dispenser (CSD)" from April 16, 2014.

Spacecraft Thermal Design, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professor Bob Twiggs on "Spacecraft Thermal Design" from April 7, 2014.