Engineering Commons^™

Development Of Mirror Flexures For Use In The Muvi Instrument, Colin W. Harrop

Master's Theses

The Miniaturized Ultraviolet Imager (MUVI), is a compact wide field UV imaging instrument in development at UC Berkeley Space Sciences Laboratory and Cal Poly, San Luis Obispo. MUVI is designed to fit in a 2U CubeSat form factor and provide wide field, high resolution images of the ionosphere at far ultraviolet wavelengths. This thesis details the design and analyses of MUVI’s deployable cover mirror mounting flexures. Three different flexure geometries were evaluated, an optimal candidate was determined based on a number of criteria including isolation of vibration and stress to the mirrors, manufacturability and cost. The design of the flexure …

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 …

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 …

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 …

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 …

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 …

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 …

On-Board Orbit Determination And 3-Axis Attitude Determination For Picosatellite Applications, John Arthur Bowen

Master's Theses

This thesis outlines an orbit determination and 3-axis attitude determination system for use on orbit as applicable to 1U CubeSats and other picosatellites. The constraints imposed by the CubeSat form factor led to the need for a simple configuration and relaxed accuracy requirements. To design a system within the tight mass, volume, and power constraints inherent to CubeSats, a balance between hardware complexity, software complexity and accuracy is sought. The proposed solution consists of a simple orbit propagator, magnetometers with a magnetic field look-up table, Sun sensors with an analytic Sun direction model, and the TRIAD method to combine vector …