Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Mechanical Engineering (169)
- Aeronautical Vehicles (61)
- Space Vehicles (53)
- Physical Sciences and Mathematics (45)
- Other Aerospace Engineering (42)
-
- Aerodynamics and Fluid Mechanics (40)
- Navigation, Guidance, Control and Dynamics (32)
- Structures and Materials (31)
- Propulsion and Power (30)
- Aviation (20)
- Systems Engineering and Multidisciplinary Design Optimization (18)
- Electrical and Computer Engineering (16)
- Physics (14)
- Materials Science and Engineering (13)
- Engineering Science and Materials (11)
- Oceanography and Atmospheric Sciences and Meteorology (10)
- Atmospheric Sciences (9)
- Heat Transfer, Combustion (8)
- Computer Sciences (7)
- Applied Mechanics (6)
- Astrodynamics (6)
- Computational Engineering (6)
- Computer Engineering (6)
- Management and Operations (6)
- Multi-Vehicle Systems and Air Traffic Control (6)
- Social and Behavioral Sciences (6)
- Applied Mathematics (5)
- Arts and Humanities (5)
- Institution
-
- University of Texas at Arlington (98)
- Embry-Riddle Aeronautical University (57)
- Air Force Institute of Technology (49)
- Purdue University (38)
- California Polytechnic State University, San Luis Obispo (37)
-
- Missouri University of Science and Technology (32)
- Utah State University (30)
- Morehead State University (22)
- University of Alabama in Huntsville (16)
- Old Dominion University (12)
- Western Michigan University (9)
- DePaul University (8)
- University of Kentucky (6)
- University of Nebraska - Lincoln (5)
- The University of Akron (3)
- University of Arkansas, Fayetteville (3)
- University of Central Florida (3)
- University of Dayton (3)
- University of South Carolina (3)
- University of Texas at El Paso (3)
- Clark University (2)
- Florida Institute of Technology (2)
- Georgia Southern University (2)
- The University of Southern Mississippi (2)
- University of South Florida (2)
- Washington University in St. Louis (2)
- Western Kentucky University (2)
- World Maritime University (2)
- Bowling Green State University (1)
- City University of New York (CUNY) (1)
- Keyword
-
- #antcenter (13)
- CFD (8)
- Aviation (7)
- UAV (7)
- Additive manufacturing (6)
-
- SAR (6)
- Aerodynamics (5)
- Computational fluid dynamics (5)
- CubeSat (5)
- Drones (5)
- Aircraft (4)
- Artificial satellites (4)
- Data center (4)
- Finite element method (4)
- Navigation (4)
- Radar (4)
- Turbulence (4)
- UAS (4)
- Ceramic fibers (3)
- Composite materials (3)
- Composites (3)
- Control (3)
- Gas turbines (3)
- Hypersonic (3)
- Optimal control (3)
- Radiation (3)
- Remote sensing (3)
- Rocket (3)
- Simulation (3)
- Supersonic (3)
- Publication
-
- Mechanical and Aerospace Engineering Theses - Archive (80)
- Theses and Dissertations (53)
- Doctoral Dissertations and Master's Theses (30)
- Robert "Bob" Twiggs STEM Education Collection (21)
- Master's Theses (19)
-
- Mechanical and Aerospace Engineering Dissertations - Archive (18)
- Mechanical and Aerospace Engineering Faculty Research & Creative Works (18)
- Space Dynamics Laboratory Publications (16)
- Open Access Theses (14)
- The Summer Undergraduate Research Fellowship (SURF) Symposium (12)
- Von Braun Symposium Student Posters (12)
- Aerospace Engineering (10)
- Aviation / Aeronautics / Aerospace International Research Conference (10)
- 2017 Academic High Altitude Conference (8)
- International Journal of Aviation, Aeronautics, and Aerospace (8)
- Masters Theses (8)
- All Graduate Theses and Dissertations, Spring 1920 to Summer 2023 (7)
- Dissertations (7)
- Doctoral Dissertations (7)
- Mechanical and Aerospace Engineering Faculty Publications (7)
- Open Access Dissertations (7)
- Mechanical & Aerospace Engineering Theses & Dissertations (6)
- Publications (6)
- Theses and Dissertations--Mechanical and Aerospace Engineering (5)
- Electronic Theses and Dissertations (4)
- Honors Theses (3)
- Mechanical Engineering (3)
- Open Access Theses & Dissertations (3)
- Research Horizons Day Posters (3)
- United States Air Force: Publications (3)
- Publication Type
- File Type
Articles 151 - 180 of 476
Full-Text Articles in Aerospace Engineering
Book Review: High G Flight - Physiological Effects And Countermeasures, Stefan Kleinke
Book Review: High G Flight - Physiological Effects And Countermeasures, Stefan Kleinke
International Journal of Aviation, Aeronautics, and Aerospace
This review provides insight on the content and a review of the quality of the recent release of High G Flight - Physiological Effects and Countermeasures from Ashgate Publications.
This review does not reflect the views of IJAAA or ERAU. This work was not peer reviewed.
High G Flight - Physiological Effects and Countermeasures
Global Optimized Isothermal And Nonlinear Models Of Earth’S Standard Atmosphere, Nihad E. Daidzic, Ph.D.,
Global Optimized Isothermal And Nonlinear Models Of Earth’S Standard Atmosphere, Nihad E. Daidzic, Ph.D.,
International Journal of Aviation, Aeronautics, and Aerospace
Both, a global isothermal temperature model and a nonlinear quadratic temperature model of the ISA was developed and presented here. Constrained optimization techniques in conjunction with the least-square-root approximations were used to design best-fit isothermal models for ISA pressure and density changes up to 47 geopotential km for NLPAM, and 86 orthometric km for ISOAM respectively. The mass of the dry atmosphere and the relevant fractional-mass scale heights have been computed utilizing the very accurate eight-point Gauss-Legendre numerical quadrature for both ISOAM and NLPAM. Both, the ISOAM and the NLPAM represent viable alternatives to ISA in many practical applications and …
Entropy Minimization Design Approach Of Supersonic Internal Passages, Jorge Sousa, Guillermo Paniagua
Entropy Minimization Design Approach Of Supersonic Internal Passages, Jorge Sousa, Guillermo Paniagua
School of Aeronautics and Astronautics Faculty Publications
Fluid machinery operating in the supersonic regime unveil avenues towards more compact technology. However, internal supersonic flows are associated with high aerodynamic and thermal penalties, which usually prevent their practical implementation. Indeed, both shock losses and the limited operational range represent particular challenges to aerodynamic designers that should be taken into account at the initial phase of the design process. This paper presents a design methodology for supersonic passages based on direct evaluations of the velocity field using the method of characteristics and computation of entropy generation across shock waves. This meshless function evaluation tool is then coupled to an …
Designing A Remote Aerial System To Image And Analyze The Health Of Grape Crops At Cal Poly San Luis Obispo, Alexander D. Vice, Dylan Benton, Adipratnia Asmady, Andrew Mercier, Andrew Meyer, Eric Belfield, Aaron Drake
Designing A Remote Aerial System To Image And Analyze The Health Of Grape Crops At Cal Poly San Luis Obispo, Alexander D. Vice, Dylan Benton, Adipratnia Asmady, Andrew Mercier, Andrew Meyer, Eric Belfield, Aaron Drake
STAR Program Research Presentations
In the last decade the prevalence of unmanned aerial vehicles (UAVs) has exploded; however, the presence of UAVs in research situations is still a relatively new and untested field. The autonomous flight lab (AFL) at Cal Poly San Luis Obispo is a new lab site that is dedicated to using UAVs to benefit research for all backgrounds. Before AFL was able to fly missions we first needed to actually receive our vehicles, create a lab space that would provide all of the necessary resources and equipment necessary to fly, and to be granted permission by the Federal Aviation Administration (FAA) …
Development Of Tools Needed For Radiation Analysis Of A Cubesat Deployer Using Oltaris, Marycarmen Gonzalez-Dorbecker
Development Of Tools Needed For Radiation Analysis Of A Cubesat Deployer Using Oltaris, Marycarmen Gonzalez-Dorbecker
Master's Theses
Currently, the CubeSat spacecraft is predominantly used for missions at Low- Earth Orbit (LEO). There are various limitations to expanding past that range, one of the major ones being the lack of sufficient radiation shielding on the Poly-Picosatellite Orbital Deployer (P-POD). The P-POD attaches to a launch vehicle transporting a primary spacecraft and takes the CubeSats out into their orbit. As the demand for interplanetary exploration grows, there is an equal increase in interest in sending CubeSats further out past their current regime. In a collaboration with NASA’s Jet Propulsion Laboratory (JPL), students from the Cal Poly CubeSat program worked …
Common Calibration Standards For Visible/Infrared Optical Sensors Are Essential To Multi-Sensor Missile Defense Architectures, Joe Tansock, Alan Thurgood, Bruce Guilmain, Garry Schnelzer
Common Calibration Standards For Visible/Infrared Optical Sensors Are Essential To Multi-Sensor Missile Defense Architectures, Joe Tansock, Alan Thurgood, Bruce Guilmain, Garry Schnelzer
Space Dynamics Laboratory Publications
Outline
- What is calibration and why is it important?
- What calibration provides to visible/infrared optical sensors being used for missile defense
- Mapping of missile defense needs to calibration domains
- Calibration planning
- Calibration examples (airborne and spaceborne)
- Summary
Examining How Breakdowns In Pilot Monitoring Of The Aircraft Flight Path, Robert Sumwalt, David Cross, Dennis Lessard
Examining How Breakdowns In Pilot Monitoring Of The Aircraft Flight Path, Robert Sumwalt, David Cross, Dennis Lessard
International Journal of Aviation, Aeronautics, and Aerospace
Aircraft accident and incident data reveal that serious safety consequences can arise when flight crewmembers fail to properly monitor the aircraft flight path. This research study reviewed human factors literature to better understand why pilots fail to properly monitor, and analyzed accident and incident data. Recommendations for improving monitoring performance were formulated, which may be useful to air carriers in implementing a new Federal Aviation Administration requirement that calls for specific training in monitoring.
On The Selection Of A Good Shape Parameter For Rbf Approximation And Its Application For Solving Pdes, Lei-Hsin Kuo
On The Selection Of A Good Shape Parameter For Rbf Approximation And Its Application For Solving Pdes, Lei-Hsin Kuo
Dissertations
Meshless methods utilizing Radial Basis Functions~(RBFs) are a numerical method that require no mesh connections within the computational domain. They are useful for solving numerous real-world engineering problems. Over the past decades, after the 1970s, several RBFs have been developed and successfully applied to recover unknown functions and to solve Partial Differential Equations (PDEs).
However, some RBFs, such as Multiquadratic (MQ), Gaussian (GA), and Matern functions, contain a free variable, the shape parameter, c. Because c exerts a strong influence on the accuracy of numerical solutions, much effort has been devoted to developing methods for determining shape parameters which provide …
Similarity Analysis Of A Swirling Counter-Flow, Jitesh Rane
Similarity Analysis Of A Swirling Counter-Flow, Jitesh Rane
Doctoral Dissertations and Master's Theses
Swirling counter-flows are used in numerous engineering applications, like combustion, heat exchangers, cyclonic separation and mixing, etc. These swirling counter-flows produce complex flow fields. It is important to study these types of flows in order to use them properly in many applications.
The present work provides insight into the flowfield inside a swirling counter-flow when the fluid is injected tangentially in a cylindrical container. A semi-analytical solution is developed by starting with the full Navier-Stokes equation and using a similarity analysis. A decaying swirl along the axis of the cylinder is assumed, which reduces the Navier-Stokes equations to first order …
Consensus With Reduced Communication Links Via Relative Neighboring Velocity Information, Gerardo De La Torre, Tansel Yucelen
Consensus With Reduced Communication Links Via Relative Neighboring Velocity Information, Gerardo De La Torre, Tansel Yucelen
Mechanical and Aerospace Engineering Faculty Research & Creative Works
In this paper, a consensus protocol is introduced to virtually manipulate the communication topology of a given networked multiagent system - without adding physical edges to the graph. The proposed protocol achieves this objective by utilizing not only neighboring agents' relative position information but also their possibly delayed velocity information. It is shown that the stability of the proposed framework is not dependent on the possible time delay present in the neighboring velocity information. In addition, it is formally proven that utilization of the proposed consensus protocol is equivalent to the addition of virtual communication links in a standard consensus …
Adaptive Control With Nonlinear Reference Systems, Tansel Yucelen, Benjamin Gruenwald, Jonathan A. Muse, Gerardo De La Torre
Adaptive Control With Nonlinear Reference Systems, Tansel Yucelen, Benjamin Gruenwald, Jonathan A. Muse, Gerardo De La Torre
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Although reference systems with linear dynamics are common in the adaptive control literature, they can lead to limitations on the achievable closed-loop dynamical system performance. This is due to the fact that linear reference systems can only approximate the desired closed-loop behavior of nonlinear dynamical systems in narrow regions of the state-space. In this paper, we study a new adaptive control architecture for uncertain dynamical systems based on a nonlinear reference system. It is shown that the system error between the uncertain dynamical system and the nonlinear reference system asymptotically vanishes in steady-state, and its performance is guaranteed during the …
Exploitation Of Heterogeneity In Distributed Sensing: An Active-Passive Networked Multiagent Systems Approach, John Daniel Peterson, Tansel Yucelen, Girish Chowdhary, Suresh Kannan
Exploitation Of Heterogeneity In Distributed Sensing: An Active-Passive Networked Multiagent Systems Approach, John Daniel Peterson, Tansel Yucelen, Girish Chowdhary, Suresh Kannan
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Most distributed sensing methods assume that the expected value of sensed information is same for all agents - ignoring differences in sensor capabilities due to, for example, environmental factors and sensors' quality and condition. In this paper, we present a distributed sensing framework to exploit heterogeneity in information provided about a dynamic environment using an active-passive networked multiagent systems approach. Specifically, this approach consists of agents subject to exogenous inputs (active agents) and agents without any inputs (passive agents). In addition, if an active agent senses a quantity accurately (resp., not accurately), then it is weighted high (resp., low) in …
Analysis And Design Of Adaptive Control Systems With Unmodeled Input Dynamics Via Multiobjective Convex Optimization, Mario Luca Fravolini, Tansel Yucelen, Jonathan Muse, Paolo Valigi
Analysis And Design Of Adaptive Control Systems With Unmodeled Input Dynamics Via Multiobjective Convex Optimization, Mario Luca Fravolini, Tansel Yucelen, Jonathan Muse, Paolo Valigi
Mechanical and Aerospace Engineering Faculty Research & Creative Works
A challenging problem for adaptive control systems is the accurate characterization of the transient response in the presence of dynamic uncertainties such as a partially known actuator. Considering an actuator modelled as a first order filter with an uncertain control effectiveness and using a projection mechanism for parameters adaptation, we show that the tracking error dynamics behaves as a linear system perturbed by bounded uncertainties. This brings the advantage that the stability analysis can be cast in terms of LMIs so that convex optimization tools can be used for analysis and design. In this framework we propose a mixed linear/adaptive …
Exploring New Lagrangian Cyclers To Enhance Science: Communications With Cubesat Technology, Pedro P. Llanos, Abdiel Santos Galindo, John Ford
Exploring New Lagrangian Cyclers To Enhance Science: Communications With Cubesat Technology, Pedro P. Llanos, Abdiel Santos Galindo, John Ford
Publications
This paper discusses the opportunities that abound by using the CubeSat technology to travel to and communicate with the International Space Station, explore space, monitor space weather, monitor space debris and perhaps travel to Mars.
The Robert & Esther Goddard Papers, Robert H. Goddard
The Robert & Esther Goddard Papers, Robert H. Goddard
Finding Aids
Dr. Robert H. Goddard was a member of the Clark Physics Department for 29 years. Foremost American pioneer of rocket research, he laid the technical and theoretical foundations for many of the developments in long-range rockets, missiles, satellites and space flight, which collectively put us into the Space Age.
The collection includes correspondence, diaries, journals, patent applications and awards, reports, and photographs. The collection also includes original paintings by Dr. Goddard.
Bio-Fuel Alternatives In South African Airways (Saa) Operations - Is It An Effective Response To Vulnerability Over Carbon Taxes And Penalty?, Daniel Kwasi Adjekum
Bio-Fuel Alternatives In South African Airways (Saa) Operations - Is It An Effective Response To Vulnerability Over Carbon Taxes And Penalty?, Daniel Kwasi Adjekum
International Journal of Aviation, Aeronautics, and Aerospace
The paper did a comparative analysis of the carbon emission and European Union Emission Trading Surcharges (EU ETS) of South African Airways (SAA) current fleet that used aviation jet A1 fuel and the same fleet if it had used a 25% bio-fuel ‘drop in’ for the European routes within the first quarter of the 2014 flying year (FY 14). Operational data in terms of the flight scheduled, aircraft type, total time enroute, route stage length, passenger estimates were obtained through SAA’s flight operations website. An independent t–test was conducted to compare means of the emissions. The mean carbon dioxide …
How To Save The World: One Life (And Uav) At A Time!, Natalie A. Wright
How To Save The World: One Life (And Uav) At A Time!, Natalie A. Wright
STAR Program Research Presentations
The proliferation of Uninhabited Aerial Vehicles (UAV’s) in commercial and public service aviation arenas has begun to gain the attention of many citizens. Popularized vehicles such as quadcopters have applications in aerial photography, small package delivery and hobbyist/consumer interests. Use of small-scale, fixed- and rotary-wing, remotely operated systems has been popularized as a result of such vehicles’ size and operational simplicity, which widens the range of application of this technology. Public service applications have the potential to advance emergency services management, which can substantially contribute to the public wellbeing. This research will examine the utility of multi-rotor systems in the …
Evaluation Of Different Optimal Control Problem Formulations For Solving The Muscle Redundancy Problem, Friedl De Groote, Allison Kinney, Anil Rao, Benjamin J. Fregly
Evaluation Of Different Optimal Control Problem Formulations For Solving The Muscle Redundancy Problem, Friedl De Groote, Allison Kinney, Anil Rao, Benjamin J. Fregly
Mechanical and Aerospace Engineering Faculty Publications
This study evaluates several possible optimal control problem formulations for solving the muscle redundancy problem with the goal of identifying the most efficient and robust formulation. One novel formulation involves the introduction of additional controls that equal the time derivative of the states, resulting in very simple dynamic equations. The nonlinear equations describing muscle dynamics are then imposed as algebraic constraints in their implicit form, simplifying their evaluation. By comparing different problem formulations for computing muscle controls that can reproduce inverse dynamic joint torques during gait, we demonstrate the efficiency and robustness of the proposed novel formulation.
Bio-Fuel Alternatives In South African Airways (Saa) Operations - Is It An Effective Response To Vulnerability Over Carbon Taxes And Penalty?, Daniel Kwasi Adjekum
Bio-Fuel Alternatives In South African Airways (Saa) Operations - Is It An Effective Response To Vulnerability Over Carbon Taxes And Penalty?, Daniel Kwasi Adjekum
Aviation Faculty Publications
The paper did a comparative analysis of the carbon emission and European Union Emission Trading Surcharges (EU ETS) of South African Airways (SAA) current fleet that used aviation jet A1 fuel and the same fleet if it had used a 25% bio-fuel ‘drop in’ for the European routes within the first quarter of the 2014 flying year (FY 14). Operational data in terms of the flight scheduled, aircraft type, total time enroute, route stage length, passenger estimates were obtained through SAA’s flight operations website. An independent t–test was conducted to compare means of the emissions. The mean carbon dioxide …
Flight Dynamics Nonlinearity Assessment Across A New Aerodynamic Attitude Flight Envelope, Ayman Muhammad Abdallah
Flight Dynamics Nonlinearity Assessment Across A New Aerodynamic Attitude Flight Envelope, Ayman Muhammad Abdallah
Mechanical & Aerospace Engineering Theses & Dissertations
A new asymmetric level aerodynamic attitude flight envelope is introduced in this dissertation. The aerodynamic attitude envelope is an angle of attack vs. sideslip angle region which describes the extent of where an aircraft can sustain a steady slipping horizontal flight condition. The new envelope is thus an extension of the more common speed-altitude symmetric level flight envelope. This new envelope can be used for design requirements, dynamic analysis, control synthesis, or performance comparison. Moreover, this envelope provides enhanced insight into trimability-controllability limitations within the aircraft design model. The aerodynamic attitude flight envelope is constructed for a six degree of …
Nano Scale Mechanical Analysis Of Biomaterials Using Atomic Force Microscopy, Diganta Dutta
Nano Scale Mechanical Analysis Of Biomaterials Using Atomic Force Microscopy, Diganta Dutta
Mechanical & Aerospace Engineering Theses & Dissertations
The atomic force microscope (AFM) is a probe-based microscope that uses nanoscale and structural imaging where high resolution is desired. AFM has also been used in mechanical, electrical, and thermal engineering applications. This unique technique provides vital local material properties like the modulus of elasticity, hardness, surface potential, Hamaker constant, and the surface charge density from force versus displacement curve. Therefore, AFM was used to measure both the diameter and mechanical properties of the collagen nanostraws in human costal cartilage. Human costal cartilage forms a bridge between the sternum and bony ribs. The chest wall of some humans is deformed …
Self-Organization Of Protein Fibers In Weightlessness, Dylan Bell
Self-Organization Of Protein Fibers In Weightlessness, Dylan Bell
Theses and Dissertations
It is currently hypothesized and widely believed that the growth of self aggregating protein chains such as amyloid fibers has a direct effect on the function of the human brain. We hypothesized creating self-assembling protein in weightlessness would allow the aggregation to continue for a longer period of time in solution without sedimentation. When protein de-natures and self-organizes into amyloid fibers the effect can be detrimental. Some neurodegenerative diseases, such as Alzheimer’s and Dementia, are believed to be caused by the collection of these fibers made from proteins such as tau and amyloid-β. For the purpose of this experiment, lysozyme …
Development Of An Interactive Wave Drag Capability For The Openvsp Parametric Geometry Tool, Michael Jon Waddington
Development Of An Interactive Wave Drag Capability For The Openvsp Parametric Geometry Tool, Michael Jon Waddington
Master's Theses
Minimizing wave drag is critical to successful and efficient transonic and supersonic flight. Area-ruling is the process of managing the cross-sectional area of an aircraft to lessen the wave drag experienced in flight. Effectively calculating the necessary areas for a given aircraft can be difficult, and existing tools for conducting a wave drag analysis often carry limitations in both functionality and availability.
In this work, the author utilized an existing parametric geometry tool named OpenVSP to create an interactive design tool for approximating zero-lift wave drag. Here, the wave drag calculation methodology used in industry for decades is combined with …
Directional Camera Control On High Altitude Balloons, Matthew M. Plewa, Brent Scharlau
Directional Camera Control On High Altitude Balloons, Matthew M. Plewa, Brent Scharlau
2017 Academic High Altitude Conference
The research reported in this paper examined the design and control of a gimbal for solar eclipse tracking and video recording. The gimbal design required 3 axes of rotation to allow for full range of motion. Utilizing individual brushless motors for each of the axes ensure minimum rotational requirements on each axes. In controlling the gimbal, both a mathematical and visual method were utilized. The mathematical method is a modified version of what is currently used for solar array pointing. The visual method looks at where the position of the sun is within the image and determines what angle changes …
An Overview Of A Solar Eclipse Video Payload, Alexander M. Peters
An Overview Of A Solar Eclipse Video Payload, Alexander M. Peters
2017 Academic High Altitude Conference
The HABET group at Iowa State University has been designing and building balloon payloads for years, giving students hands on experience with the engineering involved in creating and launching payloads to near space conditions. After attending the AHAC conference in 2014 the group begain to design a balloon for the 2017 solar eclipse. Working closely with the Space Grant Consortium’s design team, HABET has designed and completed preliminary testing on a Solar Eclipse Video payload. This payload uses multiple subsystems to complete the mission. The mission required an altitude control system, live video downlink, and a camera pointing system. Our …
Computational Fluid Dynamics Study Of Balloon System Tethered To A Stratosail, Jayakanth Loganathan, Kian-Meng Lim, Heow Pueh Lee, Boo Cheong Khoo
Computational Fluid Dynamics Study Of Balloon System Tethered To A Stratosail, Jayakanth Loganathan, Kian-Meng Lim, Heow Pueh Lee, Boo Cheong Khoo
2017 Academic High Altitude Conference
In this paper, we present a numerical study of a stratospheric balloon system tethered to a passive device, known as the Stratosail, for station-keeping operation. For scientific applications, stratospheric balloons that operate at altitudes between 15 and 20 km will need to maintain station over a fixed point above the earth for a prescribed period of time. This is a challenging problem due to the limitation of payloads and lack of an energy source. The present study uses computational fluid dynamics (CFD) simulations to analyze the drift velocity of such a balloon-Stratosail system under typical wind conditions in the stratosphere. …
Techniques For Payload Stabilization For Improved Photography During Stratospheric Balloon Flights, James Flaten, Christopher Gosch, Joseph (Benjamin) Habeck
Techniques For Payload Stabilization For Improved Photography During Stratospheric Balloon Flights, James Flaten, Christopher Gosch, Joseph (Benjamin) Habeck
2017 Academic High Altitude Conference
Payload-box rotation and swing are perennial challenges to achieving high-quality photography (typically videography) during weather-balloon flights to “near-space” (AKA the stratosphere). Continuous camera motion can lead to blurred still photos, nearly-impossible-to-watch video footage, and precludes time-exposure photography required for most astronomical imaging even though altitudes are reached where the daytime sky appears black. Apparently-random payload rotation, persisting even at altitude, can often exceed servo rotation rates and frustrate attempts to do active camera pointing. Here we discuss mostly-passive payload stabilization strategies we, and our collaborators, have used to mitigate and dampen both swing and rotation of suspended payloads on high-altitude …
Slipstream Measurements Of Small-Scale Propellers At Low Reynolds Numbers, Robert W. Deters, Gavin K. Ananda, Michael S. Selig
Slipstream Measurements Of Small-Scale Propellers At Low Reynolds Numbers, Robert W. Deters, Gavin K. Ananda, Michael S. Selig
Publications
The continuing growth in the use of small UAVs has required the need to more fully understand the propellers that power them. Part of this understanding is the behavior of the propeller slipstream. Using a 7-hole probe, the slipstreams of several small-scale propellers (diameters of 4.2, 5, and 9 in) were measured in both static (V∞ = 0) and advancing-flow (V∞ > 0) conditions at several locations downstream. For static conditions, as the slipstream expanded downstream, the maximum values of the axial and swirl velocities decreased. The general shape of the static slipstream was also found to be nearly the same …
The “Stratospheric Cricket Keeper” – Developing A Simple“Life-Support” Payload For High-Altitude Balloon Missions, Lucas Kramer, Chad Serba, James Flaten
The “Stratospheric Cricket Keeper” – Developing A Simple“Life-Support” Payload For High-Altitude Balloon Missions, Lucas Kramer, Chad Serba, James Flaten
2017 Academic High Altitude Conference
Exposure to the environmental conditions of “near-space” (AKA the stratosphere) is quickly fatal to nearly all forms of animal life. It is even challenging to build a sealable enclosure that can keep insects (crickets) alive through the dramatic and simultaneous pressure and temperature drops experienced during a high-altitude balloon mission. This poster describes the development of a rugged “cricket keeper” in which we were able to fly crickets to the stratosphere and, quoting the words of JFK, “return (them) safely to the earth!” This “life-support” payload had large windows (for the view!) and included Arduino-logged temperature and pressure sensors, an …
Using Tank Pressure To Determine The Lift Of A Balloon, Sarah M. Biver
Using Tank Pressure To Determine The Lift Of A Balloon, Sarah M. Biver
2017 Academic High Altitude Conference
An important aspect of high altitude ballooning is accuracy regarding the calculation of helium inflation in the balloon. If the balloon is over-filled it will increase rapidly in velocity and burst too quickly to record data. If the balloon is under-filled the rate of ascension will be too slow or not at all. This paper highlights the importance of accuracy in helium inflation by examining a method that uses pressure to control the inflation of a high altitude balloon. On every helium tank there is a pressure gauge, which can be used to monitor the change in pressure. Using that …