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Computation Time Comparison Between Matlab And C++ Using Launch Windows, Tyler Andrews 2012 California Polytechnic State University, San Luis Obispo

Computation Time Comparison Between Matlab And C++ Using Launch Windows, Tyler Andrews

Aerospace Engineering

Processing speed between Matlab and C++ was compared by examining launch windows and handling large amounts of data found in pork chop plots. A compilation of code was generated in Matlab to produce the plots and an identical file was created in C++ that was then compiled and run in Matlab to plot the data. This file is known as a MEX-file. This report outlines some of the basics when working with MEX-files and the problems that face users. For Lambert’s solver, multi revolution cases were considered and some pork chop plots of single revolution trajectories were plotted. Three different …


Accelerating Lambert's Problem On The Gpu In Matlab, Nathan Parrish 2012 California Polytechnic State University, San Luis Obispo

Accelerating Lambert's Problem On The Gpu In Matlab, Nathan Parrish

Aerospace Engineering

The challenges and benefits of using the GPU to compute solutions to Lambert’s Problem are discussed. Three algorithms (Universal Variables, Gooding’s algorithm, and Izzo’s algorithm) were adapted for GPU computation directly within MATLAB. The robustness of each algorithm was considered, along with the speed at which it could be computed on each of three computers. All algorithms used were found to be completely robust. Computation time was measured for computation within a for-loop, a parfor-loop, and a call to the MATLAB command ‘arrayfun’ with gpuArray-type inputs. Then, a Universal Variables Lambert’s solver was written in CUDA and compiled for use …


The Numerical Open-Source Many-Body Simulator (Noms), Jason Lloyd Daniel, Javen Kyle Foster-O'Neal 2012 California Polytechnic State University, San Luis Obispo

The Numerical Open-Source Many-Body Simulator (Noms), Jason Lloyd Daniel, Javen Kyle Foster-O'Neal

Aerospace Engineering

This paper outlines the setup and creation of an object-oriented N-body simulator as part of a continued project to explore physical phenomenon and human-computer natural interaction technologies. The tools and processes required to build an N-body simulator are also included. Several integrators were evaluated based on their ability to maintain system energy The 2nd order integrator Verlet and 3rd order integrator Hermite algorithms had the greatest accuracy to model large-scale N-body dynamics for their given computation time. Other algorithms required significantly shorter time steps to achieve similar short-term accuracy. At present, NOMS can reasonably simulate 10,000 particles at less than …


Comprehensive Matlab Gui For Determining Barycentric Orbital Trajectories, Steve Katzman 2012 California Polytechnic State University, San Luis Obispo

Comprehensive Matlab Gui For Determining Barycentric Orbital Trajectories, Steve Katzman

Aerospace Engineering

When a 3-body gravitational system is modeled using a rotating coordinate frame, interesting applications become apparent. This frame, otherwise known as a barycentric coordinate system, rotates about the system’s center of mass. Five unique points known as Lagrange points rotate with the system and have numerous applications for spacecraft operations. The goal of the Matlab GUI was to allow easy manipulation of trajectories in a barycentric coordinate system to achieve one of two end goals: a free-return trajectory or a Lagrange point rendezvous. Through graphical user input and an iterative solver, the GUI is capable of calculating and optimizing both …


De-Orbiting Upper Stage Rocket Bodies Using A Deployable High Altitude Drag Sail, Robert A. Hawkins Jr., Joseph A. Palomares 2012 California Polytechnic State University, San Luis Obispo

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 …


Optimization And Design For Heavy Lift Launch Vehicles, Paul Andreas Ritter 2012 University of Tennessee - Knoxville

Optimization And Design For Heavy Lift Launch Vehicles, Paul Andreas Ritter

Masters Theses

The simulation and evaluation of an orbital launch vehicle requires consideration of numerous factors. These factors include, but are not limited to the propulsion system, aerodynamic effects, rotation of the earth, oblateness, and gravity. A trajectory simulation that considers these different factors is generated by a code developed for this thesis titled Trajectories for Heavy-lift Evaluation and Optimization (THEO). THEO is a validated trajectory simulation code with the ability to model numerous launch configurations. THEO also has the capability to provide the means for an optimization objective. Optimization of a launch vehicle can be specified in terms of many different …


Sun-Synchronous Orbit Slot Architecture Analysis And Development, Eric Watson 2012 California Polytechnic State University, San Luis Obispo

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.


A Survey Of Mission Opportunities To Trans-Neptunian Objects – Part Ii, Ashley M. Gleaves 2012 University of Tennessee - Knoxville

A Survey Of Mission Opportunities To Trans-Neptunian Objects – Part Ii, Ashley M. Gleaves

Chancellor’s Honors Program Projects

No abstract provided.


Asteroid Retrieval Feasibility Study, John Brophy, Fred Culick, Louis Friedman, Pedro Llanos, et al. 2012 California Institute of Technology

Asteroid Retrieval Feasibility Study, John Brophy, Fred Culick, Louis Friedman, Pedro Llanos, Et Al.

Publications

This report describes the results of a study sponsored by the Keck Institute for Space Studies (KISS) to investigate the feasibility of identifying, robotically capturing, and returning an entire Near-Earth Asteroid (NEA) to the vicinity of the Earth by the middle of the next decade. The KISS study was performed by people from Ames Research Center, Glenn Research Center, Goddard Space Flight Center, Jet Propulsion Laboratory, Johnson Space Center, Langley Research Center, the California Institute of Technology, Carnegie Mellon, Harvard University, the Naval Postgraduate School, University of California at Los Angeles, University of California at Santa Cruz, University of Southern …


Applications Of Aerodynamic Forces For Spacecraft Orbit Maneuverability In Operationally Responsive Space And Space Reconstitution Needs, Matthew N. Goodson 2012 Air Force Institute of Technology

Applications Of Aerodynamic Forces For Spacecraft Orbit Maneuverability In Operationally Responsive Space And Space Reconstitution Needs, Matthew N. Goodson

Theses and Dissertations

Each year multiple satellites are launched to provide end users key pieces of information. This information ranges from remote sensing data for military or civilian purposes (e.g., weather forecasting, troop movements, agricultural production, etc.) to large bandwidth telecommunications sensors. No matter the type of information needed, society is demanding more. Because of this continual rise in information needs, the current model of launching one satellite for one mission is not sustainable. To satisfy the information needs of nations across the globe, a means for satellites to transition from one mission type to another must be developed. One means of transitioning …


Trajectory Control And Optimization For Responsive Spacecraft, Costantinos Zagaris 2012 Air Force Institute of Technology

Trajectory Control And Optimization For Responsive Spacecraft, Costantinos Zagaris

Theses and Dissertations

The concept of responsive space has been gaining interest, and growing to include systems that can be re-tasked to complete multiple missions within their lifetime. The purpose of this study is to develop an algorithm that produces a maneuver trajectory that will cause a spacecraft to arrive at a particular location within its orbit earlier than expected. The time difference, delta t, is used as a metric to quantify the effects of the maneuver. Two separate algorithms are developed. The first algorithm is an optimal control method and is developed through Optimal Control Theory. The second algorithm is a feedback …


Investigating Various Propulsion Systems For An External Attachment For A Controlled-Manual De-Orbit Of The Hubble Space Telescope, Nelson de Guia 2012 California Polytechnic State University, San Luis Obispo

Investigating Various Propulsion Systems For An External Attachment For A Controlled-Manual De-Orbit Of The Hubble Space Telescope, Nelson De Guia

Aerospace Engineering

This reports explains the results for a proposed senior project. This project concerns the Hubble Space Telescope, and exploring the possibility of having an external propulsion attachment for a manual de-orbit. The Hubble Space Telescope was proposed to return to Earth via the Space Shuttle. Although, through the current U.S. Space Administration, the Space Shuttle has been retired before the Hubble Space Telescope was retrieved. By completing this project, the results could provide insight to what type of propulsion would best de-orbit the Hubble upon its retirement. Different propulsion systems were considered to attempt to determine an optimal attachment, varying …


Global Optimization Of Mga-Dsm Problems Using The Interplanetary Gravity Assist Trajectory Optimizer (Igato), Jason M. Bryan 2011 California Polytechnic State University, San Luis Obispo

Global Optimization Of Mga-Dsm Problems Using The Interplanetary Gravity Assist Trajectory Optimizer (Igato), Jason M. Bryan

Master's Theses

Interplanetary multiple gravity assist (MGA) trajectory optimization has long been a field of interest to space scientists and engineers. Gravity assist maneuvers alter a spacecraft's velocity vector and potentially allow spacecraft to achieve changes in velocity which would otherwise be unfeasible given our current technological limitations. Unfortunately, designing MGA trajectories is difficult and in order to find good solutions, deep space maneuvers (DSM) are often required which further increase the complexity of the problem. In addition, despite the active research in the field over the last 50 years, software for MGA trajectory optimization is scarce. A few good commercial, and …


Comet: Constrained Optimization Of Multiple-Dimensions For Efficient Trajectories, Michael Curt Conrad 2011 California Polytechnic State University, San Luis Obispo

Comet: Constrained Optimization Of Multiple-Dimensions For Efficient Trajectories, Michael Curt Conrad

Master's Theses

The paper describes the background and concepts behind a master’s thesis platform known as COMET (Constrained Optimization of Multiple-dimensions for Efficient Trajectories) created for mission designers to determine and evaluate suitable interplanetary trajectories. This includes an examination of the improvements to the global optimization algorithm, Differential Evolution, through a cascading search space pruning method and decomposition of optimization parameters. Results are compared to those produced by the European Space Agency’s Advanced Concept Team’s Multiple Gravity Assist Program. It was found that while discrepancies in the calculation of ΔV’s for flyby maneuvers exist between the two programs, COMET showed a noticeable …


Formulation Of An Optimal Search Strategy For Space Debris At Geo, Daniel J. Jackson 2011 California Polytechnic State University, San Luis Obispo

Formulation Of An Optimal Search Strategy For Space Debris At Geo, Daniel J. Jackson

Master's Theses

The purpose of this thesis is to create a search strategy to find orbital debris when the object fails to appear in the sky at its predicted location. This project is for NASA Johnson Space Center Orbital Debris Program Office through the MODEST (Michigan Orbital Debris Survey Telescope) program. This thesis will build upon the research already done by James Biehl in “Formulation of a Search Strategy for Space Debris at GEO.” MODEST tracks objects at a specific right ascension and declination. A circular orbit assumption is then used to predict the location of the object at a later time. …


An Analysis Of Stabilizing 3u Cubesats Using Gravity Gradient Techniques And A Low Power Reaction Wheel, Erich Bender 2011 California Polytechnic State University, San Luis Obispo

An Analysis Of Stabilizing 3u Cubesats Using Gravity Gradient Techniques And A Low Power Reaction Wheel, Erich Bender

Aerospace Engineering

The purpose of this paper is to determine the feasibility of gravity gradient stabilizing a 3U CubeSat and then using a miniature reaction wheel to further increase stability characteristics. This paper also serves as a guide to understanding and utilizing quaternions in attitude control analysis. The analytical results show that using 33 centimeter booms and 400 gram tip masses, a 3U CubeSat will experience a maximum of 6 degrees of angular displacement in yaw and pitch, and less than .5 degrees of angular displacement in the nadir axis. A .120 kilogram miniature reaction wheel developed by Sinclair Interplanetary was introduced …


An Analysis Of N-Body Trajectory Propagation, Emerson Frees II 2011 California Polytechnic State University, San Luis Obispo

An Analysis Of N-Body Trajectory Propagation, Emerson Frees Ii

Aerospace Engineering

Trajectories created with n-body orbit models were propagated in geocentric and interplanetary test cases. The n-body models were created in MATLAB® using numerical integration. In the geocentric test case, the n-body codes were compared to a two-body orbit model and to the default HPOP model used in Satellite Tool Kit®. The interplanetary test case compared the n-body model to the HORIZONS ephemeris data from JPL and an equation for ephemeris propagation. Both cases used the same initial positions and velocities and were propagated for the same duration. The results of the analysis showed that while n-body models …


Design, Fabrication, And Testing Of An Electromagnetic Rail Gun For The Repeated Testing And Simulation Of Orbital Debris Impacts, Jeff Maniglia, Jordan Smiroldo, Alex Westfall, Guy Zohar 2011 California Polytechnic State University, San Luis Obispo

Design, Fabrication, And Testing Of An Electromagnetic Rail Gun For The Repeated Testing And Simulation Of Orbital Debris Impacts, Jeff Maniglia, Jordan Smiroldo, Alex Westfall, Guy Zohar

Aerospace Engineering

An Electromagnetic Railgun (EMRG) was designed, built, and tested, capable of firing a projectile a 1 gram projectile at 650 m/s muzzle velocity. The EMRG utilizes an injector, a high voltage power supply, a capacitor bank, inductors and rails. The injector fires 2300 psig Nitrogen gas into the system to provide an initial velocity. The high voltage power supply charges the capacitor bank. The capacitor bank discharges the electric potential built up through the projectile while inside the rails in order to create the EMRG’s force. The inductors are used to pulse form the capacitor bank in order to get …


Development And Analysis Of Onboard Translunar Injection Targeting Algorithms, Phillippe Lyles Winters Reed 2011 University of Tennessee, Knoxville

Development And Analysis Of Onboard Translunar Injection Targeting Algorithms, Phillippe Lyles Winters Reed

Masters Theses

Several targeting algorithms are developed and analyzed for possible future use onboard a spacecraft. Each targeter is designed to determine the appropriate propulsive burn for translunar injection to obtain desired orbital parameters upon arrival at the moon. Primary design objectives are to minimize the computational requirements for each algorithm but also to ensure reasonable accuracy, so that the algorithm’s errors do not force the craft to conduct large mid-course corrections. Several levels of accuracy for dynamical models are explored, the convergence range and speed of each algorithm are compared, and the possible benefits of the Broyden and trust-region targeters are …


Mapping Galileo's Trajectory, Mark Woods 2011 California Polytechnic State University, San Luis Obispo

Mapping Galileo's Trajectory, Mark Woods

Aerospace Engineering

The NASA Galileo mission was mapped out using a patched conics approximation. Galileo launched from Earth, underwent a gravity assist from Venus back to Earth for another gravity assist. Galileo then came back to Earth for one more gravity assist to propel it to Jupiter. A simulation ignoring all perturbations (i.e. third body effects, zonal (harmonics, solar wind, drag) was carried out. The simulation was able to make it to the final Earth flyby before diverging from the actual trajectory. The simulated and actual flyby dates all differed by less than 5 hours, and the simulated and actual flyby altitudes …


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