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Spacecraft Trajectory Planning For Optimal Observability Using Angles-Only Navigation, Francisco José Franquiz 2019 Embry-Riddle Aeronautical University

Spacecraft Trajectory Planning For Optimal Observability Using Angles-Only Navigation, Francisco José Franquiz

Doctoral Dissertations and Master's Theses

This work leverages existing techniques in angles-only navigation to develop optimal range observability maneuvers and trajectory planning methods for spacecraft under constrained relative motion. The resulting contribution is a guidance method for impulsive rendezvous and proximity operations valid for elliptic orbits of arbitrary eccentricity.

The system dynamics describe the relative motion of an arbitrary number of maneuvering (chaser) spacecraft about a single non-cooperative resident-space-object (RSO). The chaser spacecraft motion is constrained in terms of the 1) collision bounds of the RSO, 2) maximum fuel usage, 3) eclipse avoidance, and 4) optical sensor field of view restrictions. When more than one …


First Approach To Coupling Of Numerical Lifting-Line Theory And Linear Covariance Analysis For Uav State Uncertainty Propagation, Cory D. Goates, Randall S. Christensen, Robert C. Leishman 2019 Utah State University

First Approach To Coupling Of Numerical Lifting-Line Theory And Linear Covariance Analysis For Uav State Uncertainty Propagation, Cory D. Goates, Randall S. Christensen, Robert C. Leishman

Faculty Publications

Numerical lifting-line is a computationally efficient method for calculating aerodynamic forces and moments on aircraft. However, its potential has yet to be tapped for use in guidance, navigation, and control (GN&C). Linear covariance analysis is becoming a popular GN&C design tool and shows promise for pairing with numerical lifting-line. Pairing numerical lifting-line with linear covariance analysis allows for forward propagation of state uncertainty for real-time decision making. We demonstrate this for select state variables in a drone aerial recapture situation. Linear covariance analysis uses finite difference derivatives obtained from numerical lifting-line to calculate force and moment variances. These show agreement …


Machine Learning Methods For Rapid Inspection Of Automated Fiber Placement Manufactured Composite Structures, Christopher Sacco 2019 University of South Carolina

Machine Learning Methods For Rapid Inspection Of Automated Fiber Placement Manufactured Composite Structures, Christopher Sacco

Theses and Dissertations

The advanced manufacturing capabilities provided through the automated fiber placement (AFP) system has allowed for faster layup time and more consistent production across a number of different geometries. This contributes to the modern production of large composite structures and the widespread adaptation of composites in industry in general and aerospace in particular. However, the automation introduced in this process increases the difficulty of quality assurance efforts and inspection. The AFP process can induce a number of manufacturing defects including wrinkles, twists, gaps, and overlaps. The manual identification of these defects is often laborious and requires a measure of expert knowledge. …


Nonlinear Observer For Visual-Inertial Navigation Using Intermittent Landmark Measurements, Miaomiao Wang 2019 Western University

Nonlinear Observer For Visual-Inertial Navigation Using Intermittent Landmark Measurements, Miaomiao Wang

Western Research Forum

The development of reliable orientation, position and linear velocity estimation algorithms for the 3D visual-inertial navigation system (VINS) is instrumental in many applications, such as autonomous underwater vehicles (AUVs), and unmanned aerial vehicles (UAVs). It is extremely important when the global position system (GPS) is not available in GPS-denied environments. Recently, observers design for VINS using landmark position measurements from Kinect sensors or stereo cameras has been increasingly investigated in the literature.

The aim of this work is to design a nonlinear observer for VINS under the assumption that landmark position measurements are intermittent. In practice, the landmark measurements are …


Low-Cost Applications Of Composite Pressure Vessels In Solid Rocket Motor Design, Riley Meik, Andy George 2019 Brigham Young University

Low-Cost Applications Of Composite Pressure Vessels In Solid Rocket Motor Design, Riley Meik, Andy George

Journal of Undergraduate Research

For years, the delivery of payloads into space was unavailable to universities and small spacecraft companies. With growth in the space industry and advancements in rocket technology, space payload deployment became an option but was still cost-prohibitive for most. Sounding rockets, small rockets designed for low-cost, flexible access to space, were the solution. Although sounding rockets make access to space noticeably less expensive, the cost is still out of reach for low-budget space experiments. The great challenge of today is making these launch vehicles more efficient and affordable.


Turbine Passage Design Methodology To Minimize Entropy Production-A Two-Step Optimization Strategy, Paht Juangphanich, Cis De Maesschalck, Guillermo Paniagua 2019 Purdue University

Turbine Passage Design Methodology To Minimize Entropy Production-A Two-Step Optimization Strategy, Paht Juangphanich, Cis De Maesschalck, Guillermo Paniagua

School of Aeronautics and Astronautics Faculty Publications

Rapid aerodynamic design and optimization is essential for the development of future turbomachinery. The objective of this work is to demonstrate a methodology from 1D mean-line-design to a full 3D aerodynamic optimization of the turbine stage using a parameterization strategy that requires few parameters. The methodology is tested by designing a highly loaded and efficient turbine for the Purdue Experimental Turbine Aerothermal Laboratory. This manuscript describes the entire design process including the 2D/3D parameterization strategy in detail. The objective of the design is to maximize the entropy definition of efficiency while simultaneously maximizing the stage loading. Optimal design trends are …


Propulsion System Testing For A Long-Endurance Solar-Powered Unmanned Aircraft, D. Dantsker, Robert Deters, Marco Caccamo 2019 University of Illinois

Propulsion System Testing For A Long-Endurance Solar-Powered Unmanned Aircraft, D. Dantsker, Robert Deters, Marco Caccamo

Publications

The increase in popularity of unmanned aerial vehicles (UAVs) has been driven by their use in civilian, education, government, and military applications. However, limited on-board energy storage significantly limits flight time and ultimately usability. The propulsion system plays a critical part in the overall energy consumption of the UAV; therefore, it is necessary to determine the most optimal combination of possible propulsion system components for a given mission profile, i.e. propellers, motors, and electronic speed controllers (ESC). Hundreds of options are available for the different components with little performance specifications available for most of them. In order to determine the …


A Multi-Fidelity Prediction Of Aerodynamic And Sonic Boom Characteristics Of The Jaxa Wing Body, Forrest L. Carpenter, Paul G. A. Cizmas, Christian R. Bolander, Ted N. Giblette, Doug F. Hunsaker 2019 Texas A&M University

A Multi-Fidelity Prediction Of Aerodynamic And Sonic Boom Characteristics Of The Jaxa Wing Body, Forrest L. Carpenter, Paul G. A. Cizmas, Christian R. Bolander, Ted N. Giblette, Doug F. Hunsaker

Mechanical and Aerospace Engineering Student Publications and Presentations

This paper presents a detailed comparison between the linear panel solver PANAIR A502 and the in-house Navier–Stokes solver UNS3D for a supersonic low-boom geometry. The high-fidelity flow solver was used to predict both the inviscid and laminar flow about the aircraft geometry. The JAXA wing body was selected as the supersonic low-boom geometry for this study. A comparison of the undertrack near-field pressure signatures showed good agreement between the three levels of model fidelity along the first 0.8L of the signature. Large oscillations in the PANAIR results were observed. The PANAIR discrepancies were traced back to violations of the …


Investigation Into The Effects Of Blade Tip Twist On Noise Reduction For A Naca 0012 Rotor Blade, Uyen T. Sou 2019 San Jose State University

Investigation Into The Effects Of Blade Tip Twist On Noise Reduction For A Naca 0012 Rotor Blade, Uyen T. Sou

McNair Research Journal SJSU

The advancement of the urban air mobility concept is heavily dependent on the public acceptance of the aircraft vehicles used for air taxis. The importance of the perception of noise by humans is crucial to the passing of legislation and proposals working to implement the new transport system. The investigation into how the noise perception can be reduced is vital to the success of the personal air travel industry. The air taxi design has been geared towards the rotorcraft models. Therefore, the investigation into the rotor blade designs is necessary because, similar to helicopters, the main component in noise generation …


Effects And Solutions On The Human Body After Long-Duration Space Flights, Jose Jaime Esquivel Patricio 2019 San Jose State University

Effects And Solutions On The Human Body After Long-Duration Space Flights, Jose Jaime Esquivel Patricio

McNair Research Journal SJSU

During the Cold War, President John F. Kennedy made it a mission for the National Aeronautics and Space Administration (NASA) to accomplish a lunar landing and return to Earth. The final lunar landing and the last time humans left Low Earth Orbit (LEO) was in December, 1972. However, 47 years have passed and the fascination with traveling into deep space remains alive and flourishing. A major problem with future human missions to Mars is the effects of microgravity and Mars’ 0.38g environment. Unfortunately, space medicine is limited and little is known about the effects of microgravity on the human body …


An Investigation Of The Anomalous Thrust Capabilities Of The Electromagnetic Drive, Hannah J. Simons 2019 California Polytechnic State University, San Luis Obispo

An Investigation Of The Anomalous Thrust Capabilities Of The Electromagnetic Drive, Hannah J. Simons

Physics

The Electromagnetic Drive (EMDrive) is a propellant-less engine concept hypothesized by aero- space engineer Roger Shawyer. Shawyer’s proposed thruster technology is grounded on the theory of electromagnetic resonant behavior exhibited by a radiofrequency cavity, though the source of any generated thrust is undetermined by current physical laws. NASA Eagleworks Laboratories at John- son Space Center conducted a vacuum test campaign to investigate previously reported anomalous thrust capabilities of such a closed radiofrequency cavity, using a low-thrust torsion pendulum. The team published positive, although small-scaled thrust results in 2017. Following NASA Eagleworks breakthrough result and operating under the assumption that the …


Effects Of Corrugations On Stiffness Properties Of Composite Beams For Structural Applications, Jane Xiao 2019 California Polytechnic State University, San Luis Obispo

Effects Of Corrugations On Stiffness Properties Of Composite Beams For Structural Applications, Jane Xiao

Master's Theses

Composites have high strength-to-weight ratios, which is particularly desired for applications with weight restrictions. Common composite materials such as carbon fiber reinforced plastic (CF) and fiber glass reinforced plastic (FG) were used in this research. While composite materials possess high stiffness and strength properties, the stiffness of composite laminates may be maximized by changing the geometry. By adding corrugations, the flexural stiffness is increased in one direction compared to the stiffness of a flat part with the same amount of material. Thus, stiffness increases without a change in weight. The primary goal of this research was to investigate the stiffness …


Atomic Oxygen Effects On Particulate Contamination And Short Beam Strength Of Carbon Composites, Marlee K. Litzinger 2019 California Polytechnic State University, San Luis Obispo

Atomic Oxygen Effects On Particulate Contamination And Short Beam Strength Of Carbon Composites, Marlee K. Litzinger

Master's Theses

In order to design a successful space system, the unique challenges of the space environment it will operate in must be considered during the design process. Atomic oxygen (AO) is a detrimental environmental effect found in Low Earth Orbit (LEO) that affects spacecraft surfaces by oxidizing and eroding material over time, particularly polymers. Carbon fiber/epoxy composites are a commonly used spacecraft material affected by AO exposure. Carbon composites are used as a structural material, such as on solar panels; their large surface area therefore is a potential contamination source to sensitive components. The Space Environments and Testing Lab at California …


Nanoparticle Injector For Photonic Manipulators Using Dielectrophoresis, Jaykob Maser, Joshua Rovey 2019 Missouri University of Science and Technology

Nanoparticle Injector For Photonic Manipulators Using Dielectrophoresis, Jaykob Maser, Joshua Rovey

Mechanical and Aerospace Engineering Faculty Research & Creative Works

We describe the concept of a dielectrophoretic nanoparticle injector and its use in a plasmonic/photonic-based nanoparticle manipulation system. Particle motion is achieved by generating an electrostatic, non-uniform field between two tilted plates and applying the corresponding dielectrophoretic force to net-neutral nanoparticles. We investigate the dependence the dielectrophoretic force has on the plate angle of the charged plates as well as their separation distance, dielectric filler material, and exit interface membrane. Our results indicate an increasing average and maximum dielectrophoretic force attainable in the axial direction with corresponding decreasing plate angle and gap distance. The model also predicts larger field variation …


Estimation Of The Region Of Attraction Of Underactuated Systems And Its Enlargement Using Impulsive Inputs, Nilay Kant, Ranjan Mukherjee, Dhrubajit Chowdhury, Hassan K. Khalil 2019 Missouri University of Science and Technology

Estimation Of The Region Of Attraction Of Underactuated Systems And Its Enlargement Using Impulsive Inputs, Nilay Kant, Ranjan Mukherjee, Dhrubajit Chowdhury, Hassan K. Khalil

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Stabilization of an equilibrium point is an important control problem for underactuated systems. For a given control design, the ability of the system to remain stable in the presence of disturbances depends on the size of the region of attraction of the stabilized equilibrium. The sum of squares and trajectory reversing methods are combined together to generate a large estimate of the region of attraction. Then, this estimate is effectively enlarged by applying the impulse manifold method, which can stabilize equilibria from points lying outside the estimated region of attraction. In this paper, the generality of the approach is demonstrated …


Modifying Casting Parameters To Improve The High Temperature Ductility Of Investment Cast Nickel-Based Superalloy Pwa 1455, Lars Alexander Hedin, Cole Magnum Introligator 2019 California Polytechnic State University, San Luis Obispo

Modifying Casting Parameters To Improve The High Temperature Ductility Of Investment Cast Nickel-Based Superalloy Pwa 1455, Lars Alexander Hedin, Cole Magnum Introligator

Materials Engineering

PCC Structurals, an industry leader in superalloy investment castings, has observed inconsistencies in the stress rupture performance of polycrystalline nickel-based superalloy PWA 1455. PCC has changed their casting parameters to reduce the thermal gradient during cooling but have been unable to correlate these changes with an increase in stress rupture elongation. Metallographic examination of past samples indicated microstructures composed of non- equiaxed dendritic grains with mean diameter of .021 inches along the test axis. A similar study on polycrystalline superalloys has indicated that excessive superheat temperatures above the liquidus can result in large grains identical to those observed, limiting the …


Redesign Of Cubesat For Beam Charging, Kuba Preis 2019 California Polytechnic State University, San Luis Obispo

Redesign Of Cubesat For Beam Charging, Kuba Preis

Industrial and Manufacturing Engineering

This paper is intended to be a study in the applications of the design freedom granted by additive manufacture in the design of a 1U CubeSat frame. The main loads experienced by a CubeSat are structural (during launch) and thermal (solar radiation). Beam charging is an emerging technology which involves charging a CubeSat using a laser beam. In this paper, a CubeSat frame was redesigned to account for the structural loads induced during launch and the thermal loads induced when beam charging. The thermal, weight, design, and structural requirements for a new CubeSat design were derived. The 1U CubeSat frame …


A Homegrown Dsmc-Pic Model For Electric Propulsion, Dominic Charles Lunde 2019 California Polytechnic State University, San Luis Obispo

A Homegrown Dsmc-Pic Model For Electric Propulsion, Dominic Charles Lunde

Master's Theses

Powering spacecraft with electric propulsion is becoming more common, especially in CubeSat-class satellites. On account of the risk of spacecraft interactions, it is important to have robust analysis and modeling tools of electric propulsion engines, particularly of the plasma plume. The Navier-Stokes equations used in classic continuum computational fluid dynamics do not apply to the rarefied plasma, and therefore another method must be used to model the flow. A good solution is to use the DSMC method, which uses a combination of particle modeling and statistical methods for modeling the simulated molecules. A DSMC simulation known as SINATRA has been …


Colloid Thruster To Teach Advance Electric Propulsion Techniques To Post-Secondary Students, Alexander M. Powaser 2019 California Polytechnic State University, San Luis Obispo

Colloid Thruster To Teach Advance Electric Propulsion Techniques To Post-Secondary Students, Alexander M. Powaser

Master's Theses

Colloid thrusters, and electrospray thrusters as a whole, have been around since the 1960s. When they were first developed, the high efficiency and fine thrust control was overshadowed by the high power requirement for such a low thrust that the system provides. This caused the technology to be put on hold for aerospace applications. Now, as small satellites are becoming more prevalent, there has been a resurgence in interest in electrospray thruster technology. The recent advancements in tech- nology allow electrospray thrusters to use significantly less power and occupy less volume than their predecessors. As electrospray technology continues to advance, …


An Afternoon With General Thomas P. Stafford, Stafford Air & Space Museum 2019 Southwestern Oklahoma State University

An Afternoon With General Thomas P. Stafford, Stafford Air & Space Museum

Programs

An Afternoon with General Thomas P. Stafford

Sunday, May 19th, 2019 at 2:00 P.M. at the Weatherford High School Performing Arts Center.


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