Space Vehicles Commons^™

Exploring The Concept Of A Deep Space Solar-Powered Small Spacecraft, Kian Guillaume Crowley

Master's Theses

New Horizons, Voyager 1 & 2, and Pioneer 10 & 11 are the only spacecraft to ever venture past Pluto and provide information about space at those large distances. These spacecraft were very expensive and primarily designed to study planets during gravitational assist maneuvers. They were not designed to explore space past Pluto and their study of this environment is at best a secondary mission. These spacecraft rely on radioisotope thermoelectric generators (RTGs) to provide power, an expensive yet necessary approach to generating sufficient power. With Cubesats graduating to interplanetary capabilities, such as the Mars-bound MarCO spacecraft, matching the modest …

Alternative Mission Concepts For The Exploration Of Outer Planets Using Small Satellite Swarms, Andrew Gene Blocher

Master's Theses

Interplanetary space exploration has thus far consisted of single, expensive spacecraft missions. Mission costs are particularly high on missions to the outer planets and while invaluable, finite budgets limit our ability to perform extensive and frequent investigations of the planets. Planetary systems such as Jupiter and Saturn provide extremely complex exploration environments with numerous targets of interest. Exploring these targets in addition to the main planet requires multiple fly-bys and long mission timelines. In LEO, CubeSats have changed the exploration paradigm, offering a fast and low cost alternative to traditional space vehicles. This new mission development philosophy has the potential …

Radiation Exposure During Space Travel: Using Radioisotopes For A Comparative Study Of Human Feces And Urine As Integrated Shield Components, Noah L. Falck

Symposium

Earth’s atmosphere and magnetosphere deflect and absorb the majority of harmful radiation traversing Space; however, once outside Low Earth Orbit (LEO), payloads are exposed to Galactic Cosmic Rays (GCR) and Solar Particle Events (SPEs). While humans possess capabilities that hardware does not, we are uniquely vulnerable to radiation. Detrimental effects range from nausea and dizziness brought by intense, short term doses to increased cancer risk and impaired cognitive function associated with chronic exposure. This paper aims to explore the use of human waste (feces and urine) as radiation shields in a comparative study of urine v. water and hydrated v. …

Sysml Based Cubesat Model Design And Integration With The Horizon Simulation Framework, Shaun Luther

Master's Theses

This thesis examines the feasibility of substituting the system input script of Cal Poly’s Horizon Simulation Framework (HSF) with a Model Based Systems Engineering (MBSE) model designed with the Systems Modeling Language (SysML). A concurrent student project, SysML Output Interface Creation for the Horizon Simulation Framework, focused on design of the HSF Translator Plugin which converts SysML models to an HSF specific XML format. A SysML model of the HSF test case, Aeolus, was designed. The original Aeolus HSF input script and the translated SysML input script retained the format and dependency structure required by HSF. Both input scripts …

An Iteration On The Horizon Simulation Framework To Include .Net And Python Scripting, Morgan Yost

Master's Theses

Modeling and Simulation is a crucial element of the aerospace engineering design pro- cess because it allows designers to thoroughly test their solution before investing in the resources to create it. The Horizon Simulation Framework (HSF) v3.0 is an aerospace modeling and simulation tool that allows the user to verify system level requirements in the early phases of the design process. A low fidelity model of the system that is created by the user is exhaustively tested within the built-in Day-in-the-Life simulator to provide useful information in the form of failed requirements, system bottle necks and leverage points, and potential …

Structural Micrometeoroid And Radiation Shielding For Interplanetary Spacecraft, Jared Allen Ruekberg

Master's Theses

This paper focused on two significant space forces that can affect the success of a spacecraft: the radiation and micrometeoroid environments. Both are looked at in the context of the region of space between Earth and Mars. The goal was create reference environments, to provide context to results of environmental modeling, and to provide recommendations to assist in early design decisions of interplanetary spacecraft. The radiation section of this report used NASA's OLTARIS program to generate data for analysis. The area of focus was on the radiation effects for crewed missions, therefore effective dose equivalent was the metric used to …

Tesseract, Edgar Uribe, Vanessa Faune

Mechanical Engineering

PolySat is a student-run, Cal Poly research program in which students develop small satellites, known as CubeSats, to be sent into space. Since the start of the program in 2000, PolySat has developed eight 10cm x 10cm x10cm CubeSats. Recently, the team has developed two satellites of double, and triple, that size for NASA-KSC & AI-Solutions and the National Science Foundation. The recent volumetric expansion has been driven by high demand for further satellite functionality, which necessitates large power generation capabilities. To remain competitive in the growing CubeSat industry, PolySat must develop a platform that can provide enough power to …

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 …

Development Of Safety Standards For Cubesat Propulsion Systems, Liam Jon Cheney

Master's Theses

The CubeSat community has begun to develop and implement propulsion systems. This movement represents a new capability which may satisfy mission needs such as orbital and constellation maintenance, formation flight, de-orbit, and even interplanetary travel. With the freedom and capability granted by propulsion systems, CubeSat providers must accept new responsibilities in proportion to the potential hazards that propulsion systems may present.

The Cal Poly CubeSat program publishes and maintains the CubeSat Design Specification (CDS). They wish to help the CubeSat community to safety and responsibly expand its capabilities to include propulsive designs. For this reason, the author embarked on the …

Analysis Of An Inflatable Gossamer Device To Efficiently De-Orbit Cubesats, Robert A. Hawkins Jr.

Master's Theses

There is an increased need for spacecraft to quickly and efficiently de-orbit themselves as the amount of debris in orbit around Earth grows. Defunct spacecraft pose a significant threat to the LEO environment due to their risk of fragmentation. If these spacecraft are de-orbited at the end of their useful life their risk to future spacecraft is greatly lessened. A proposed method of efficiently de-orbiting spacecraft is to use an inflatable thin-film envelope to increase the body's area to mass ratio and thusly shortening its orbital lifetime. The system and analysis presented in this project is sized for use on …

Feasibility Of Cubesat Formation Flight Using Rotation To Achieve Differential Drag, Skyler M. Shuford

Aerospace Engineering

This paper presents the results of a study conducted to understand the feasibility of CubeSat formation flight. The mechanism for separation and formation studied was differential drag, achieved by rotating the CubeSats to give them different cross-sectional areas. Intuitively, lower altitude orbits provide much higher separation effects. Although the most influential orbital effects occur with maximum and minimum cross-sectional areas, an attitude-controlled and a tumbling CubeSat may provide enough differential drag to meet separation requirements of a mission. Formation flight is possible, but due to the non-linearity of the system, gain scheduling may be the most effective method of long …

Assessment For Completion Of Cp7 Integration With Revision 6 Avionics, Daniel Jennings

Electrical Engineering

he purpose of this project is the continuation of the CP7 CubeSat project, analysis for integration with new Avionics Systems, and to leave behind instruction for future work for completion of the satellite. CP7 is a satellite in development to support a mechanical and electrical system to experiment on particle damping in micro-gravity. The completion of this satellite needs to be prioritized more than it has been by the PolySat team to honor our work with Northrop Grumman, who have been supportive and helpful throughout the process. This work seeks to aid in the completion of this satellite, so that …

A Generic Decision Making Framework For Autonomous Systems, Connor Lange

Master's Theses

With the rising popularity of small satellites, such as CubeSats, many smaller institutions previously incapable of developing and deploying a spacecraft have starting to do so. Institutions with a history of space flight, such as NASA JPL, have begun to put projects on CubeSats that would normally fly on much larger satellites. As a result, the institutions with space flight heritage have begun to port spacecraft software that was previously designed for much larger and more complex satellites to the CubeSat platform. Unfortunately for universities, who are the majority of all institutions devel- oping CubeSats, these ported systems are too …

Feasibility Of Microsatellite Active Debris Removal Systems, Karsten J. James

Master's Theses

Space debris has become an increasingly hazardous obstacle to continued spaceflight operations. In an effort to mitigate this problem an investigation of the feasibility of a microsatellite active debris removal system was conducted. Through proposing a novel concept of operation, utilizing a grapple-and-tug system architecture, and by analyzing each resultant mission phase in the frame of a representative example, it was found that microsatellite scale systems are capable of fulfilling the active debris removal mission. Analysis of rendezvous, docking, control and deorbit mission requirements determined that the design of a grapple-and-tug system will be driven by sizing of the propellant …

Rocket Fuel Pressurization, Sean Green, Joe Marcinkowski, Andrew Nahab

Mechanical Engineering

No abstract provided.

Design, Fabrication, And Testing Of An Emr Based Orbital Debris Impact Testing Platform, Jeffrey J. Maniglia Jr.

Master's Theses

This paper describes the changes made from Cal Poly’s initial railgun system, the Mk. 1 railgun, to the Mk. 1.1 system, as well as the design, fabrication, and testing of a newer and larger Mk. 2 railgun system. The Mk. 1.1 system is developed as a more efficient alteration of the original Mk. 1 system, but is found to be defective due to hardware deficiencies and failure, as well as unforeseen efficiency losses. A Mk. 2 system is developed and built around donated hardware from the Naval Postgraduate School. The Mk. 2 system strove to implement an efficient, augmented, electromagnetic …

Characterization Of The Effects Of A Sun-Synchronous Orbit Slot Architecture On The Earth's Orbital Debris Environment, Connor David Noyes

Master's Theses

Low Earth orbit represents a valuable limited natural resource. Of particular interest are sun-synchronous orbits; it is estimated that approximately 44% of low Earth satellites are sun-synchronous. A previously developed sun-synchronous orbit slot architecture is considered. An in-depth analysis of the relative motion between satellites and their corresponding slots is performed. The long-term evolution of Earth's orbital environment is modeled by a set of coupled ordinary differential equations. A metric for quantifying the benefit, if any, of implementing a sun-synchronous architecture is developed. The results indicate that the proposed slot architecture would reduce the frequency of collisions between satellites in …

Ad-Hoc Regional Coverage Constellations Of Cubesats Using Secondary Launches, Guy G. Zohar

Master's Theses

As development of CubeSat based architectures increase, methods of deploying constellations of CubeSats are required to increase functionality of future systems. Given their low cost and quickly increasing launch opportunities, large numbers of CubeSats can easily be developed and deployed in orbit. However, as secondary payloads, CubeSats are severely limited in their options for deployment into appropriate constellation geometries.

This thesis examines the current methods for deploying cubes and proposes new and efficient geometries using secondary launch opportunities. Due to the current deployment hardware architecture, only the use of different launch opportunities, deployment direction, and deployment timing for individual cubes …

Validation Of The Ballistic Limit Equation For Monolithic Aluminum Shielding At Geostationary Orbital Debris Impact Velocity, Brandon Holladay

Aerospace Engineering

The Cal Poly Electro Magnetic Rail Gun was used to eject a 0.370 gram, rectangular aluminum projectile towards a 1/16 inch monolithic aluminum plate at a speed of 280 ± 50 m/s. The resulting impact left a large attached spall on the back of the shielding. The impact damage was compared to an industry ballistic limit equation for a spherical aluminum projectile of similar diameter and was shown to have slightly less damage than the expected results.

In addition, an aluminum mesh double bumper shield was fired upon in order to verify its higher protection per aerial density as well …

Optimal Slewing Of A Constrained Telescope Using Seventh Order Polynomial Input Torques, Julia K. Bush

Master's Theses

Two-axis gimbals are frequently used to point cameras and telescopes at various points of interest for surveillance, science, and art. The rotation of a two-axis gimbal system is governed by nonlinear angular momentum equations of motion. This paper presents a method for slewing a telescope in space with a gimbaled sensor attached to a nominally non-rotating spacecraft using two seventh order polynomial input functions to characterize torques. To accomplish this task, picking the optimal coefficients of the seventh order polynomial was necessary. It was also desired to use constraint equations to limit the excursion, angular velocity, angular acceleration, and jerk …

Interstellar Mission To Gliese 581, Brock Schmalzel, Brian Tsoi

Aerospace Engineering

This report details a conceptual design for a one-way, interstellar mission, based upon assumed technological advances over the next few hundred years. It addresses the unique challenges associated with an interstellar mission, looking at both developed and theoretical technologies. This report looks specifically at propulsion systems required to reach an exoplanet. In addition, the power, communication, and orbital trajectories are analyzed to see the differences and technological advancements necessary for future missions and the proposed interstellar mission. The destination for the interstellar mission in Gliese 581, a star system located 20.3 light years away and has 5 known planets and …

Development Of A Pyrotechnic Shock Simulation Apparatus For Spacecraft Applications, Joseph Binder, Matthew Mccarty, Chris Rasmussen

Aerospace Engineering

This report details the research, design, construction, and testing of a pyrotechnic shock simulation apparatus for spacecraft applications. The apparatus was developed to be used in the Space Environments Lab at California Polytechnic State University. It will be used for testing spacecraft components with dimensions up to 24”x12”x12” as well as CubeSats. Additionally, it may be used as an instructional or demonstrational tool in the Aerospace Department’s space environments course. The apparatus functions by way of mechanical impact of an approximately 20 lb stainless steel swinging hammer. Tests were performed to verify the simulator’s functionality. Suggestions for improvement and further …

Thermal Vacuum Integration For Cal Poly's Space Environments Laboratory, Chelsea Barackman, Steven Jackowski

Aerospace Engineering

The purpose of the senior project is to construct a thermal vacuum by utilizing a preexisting vacuum chamber in the Space Environments Lab, and a donated Advanced Thermal Sciences (ATS) chiller. While a thermal vacuum is already available on campus, building one for the Space Environments Lab would grant undergraduates access to the equipment, allowing a much better understanding of testing methods and procedures in use by the aerospace industry. This paper explains the design and analysis of the thermal vacuum (T-VAC) project as well as the operation and procedures required for the ATS chiller and fill/drain tank. The thermal …

De-Orbiting Upper Stage Rocket Bodies Using A Deployable High Altitude Drag Sail, Robert A. Hawkins Jr., Joseph A. Palomares

Aerospace Engineering

This report examines the effectiveness of a drag sail to de-orbit upper stage rocket bodies. Many other perturbations contribute to the de-orbiting of these rocket bodies, and these perturbations will also be discussed briefly. This paper will show the length of time needed to force the altitudes of various launch vehicle stages with varying drag area sizes to less than 100 km. The upper stage of the Delta IV launch vehicle in an orbit with an altitude of 500 km will naturally de-orbit in 720 days but when equipped with a 20 m² drag sail, it will de-orbit in …

Preliminary Design Of A Laboratory Cylindrical Hall-Effect Thruster, Scott Mcgrail, Sam Parker

Aerospace Engineering

A 3-cm cylindrical Hall thruster with permanent magnets was designed and modeled. The goal was to design a Hall thruster for Cal Poly’s propulsion laboratory of similar size and performance as Cal Poly’s MiXI thruster. The design process began with an investigation into the physics of Hall thrusters and selection of certain thruster parameters. The selected parameters were the diameter and depth of the channel, the total power input to the system, the discharge supply voltage, the cathode voltage, and the propellant flow rates to the anode and cathode. These parameters were used to determine the operational characteristics of the …

Reliable Software Updates For On-Orbit Cubesat Satellites, Sean Fitzsimmons

Master's Theses

CubeSat satellites have redefined the standard solution for conducting missions in space due to their unique form factor and cost. The harsh environment of space necessitates examining features that improve satellite robustness and ultimately extend lifetime, which is typical and vital for mission success. The CubeSat development team at Cal Poly, PolySat, has recently redefined its standard avionics platform to support more complex mission capabilities with this robustness in mind. A significant addition was the integration of the Linux operating system, which provides the flexibility to develop much more elaborate protection mechanisms within software, such as support for remote on-orbit …

Implementation Of A ¼ Inch Hollow Cathode Into A Miniature Xenon Ion Thruster (Mixi), David Wayne Knapp

Master's Theses

Over the last decade, miniature ion thruster development has remained an active area of research do to its low power, low thrust, and high efficiency, however, due to several technical issues; a flight level miniature ion thruster has proved elusive. This thesis covers the design, fabrication, assembly, and test of an altered version of the Miniature Xenon Ion thruster (MiXI), originally developed by lead engineer Dr. Richard Wirz, at the California Institute of Technology (Caltech). In collaboration with Dr. Wirz, MiXI-CP-V3 was developed at Cal Poly San Luis Obispo with the goal of implementing of a ¼ inch hollow cathode …

Sun-Synchronous Orbit Slot Architecture Analysis And Development, Eric Watson

Master's Theses

Space debris growth and an influx in space traffic will create a need for increased space traffic management. Due to orbital population density and likely future growth, the implementation of a slot architecture to Sun-synchronous orbit is considered in order to mitigate conjunctions among active satellites. This paper furthers work done in Sun-synchronous orbit slot architecture design and focuses on two main aspects. First, an in-depth relative motion analysis of satellites with respect to their assigned slots is presented. Then, a method for developing a slot architecture from a specific set of user defined inputs is derived.

Pico-Satellite Integrated System Level Test Program, Marcus A. Ruddy

Master's Theses

Testing is an integral part of a satellite’s development, requirements verification and risk mitigation efforts. A robust test program serves to verify construction, integration and assembly workmanship, ensures component, subsystem and system level functionality and reduces risk of mission or capability loss on orbit.

The objective of this thesis was to develop a detailed test program for pico-satellites with a focus on the Cal Poly CubeSat architecture. The test program established a testing baseline from which other programs or users could tailor to meet their needs. Inclusive of the test program was a detailed decomposition of discrete and derived test …

Cubesat Constellation Analysis For Data Relaying, Bradley Ryan Smalarz

Master's Theses

Current CubeSat communication technology limits the amount of time, and number of accesses with ground stations. It has been proposed to use a constellation of CubeSats to improve relay performance and increase the number of accesses between a CubeSat and ground stations. By using the spatial and temporal analysis features of STK, coupled with the STK/Matlab interface a robust tool was created to analyze the performance of CubeSat constellations based on a store-and-forward communications model which is not currently supported by the STK Engine. Utilizing the Connect messaging format through a socket connection on the local machine, a Matlab graphical …