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| AZ - Embry-Riddle Aeronautical University |
http://sites.google.com/site/apogeeastronautics/ |
| Proposal
ID: 2010-2508 |
Flight Week: June 17-26, 2010 |
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Preliminary Research for Inertia Matrix Estimation (PRIME) Satellite |
Attitude determination and control systems are very dependent on an accurate estimation of the mass moment of inertia matrix of the satellite. These values can change due to fuel consumption, fuel slosh, docking with other spacecraft, scientific experiments, debris collection, orbital maneuvering vehicle procedures, as well as a host of other factors. Missions that require very fine attitude control and docking procedures can be adversely affected by large changes in system mass properties. PRIME Sat (Primary Research for Inertia Matrix Estimator Satellite) has been developed as an experiment designed to dynamically determine the mass moment of inertia matrix of a satellite to demonstrate a system capable of overcoming the problem of in-orbit changes to inertia.
Utilizing the Reduced Gravity Student Flight Opportunities Program (RGSFOP), the PRIME Sat team will test a micro-satellite’s ability to determine its mass moment of inertia matrix. While in microgravity, PRIME Sat will use a reaction wheel to apply a known torque about a single axis. PRIME Sat will measure the resulting angular rates and determine how the system is propagating. All data measured onboard the PRIME Sat will be transferred to a ground station for storage and processing. The data will be used in an attempt to estimate an accurate mass moment of inertia matrix for the satellite, and the results will be compared to Computer Aided Design (CAD) models of the system.
Microgravity and a free-float environment are extremely important to this mission. First, any tie-down method would introduce forces that the team would be unable to measure or incorporate into the models and equations for mass moment of inertia matrix determination. Second, any apparatus designed to test the satellite in gravity (e.g. an air bearing) would introduce numerous torques on the satellite as well as restrict the freedom of movement so that there would not truly be a full three degrees of freedom. PRIME Sat must be free to rotate 360 degrees about all 3 axes or the system will be unable to determine the products of inertia because of the dependence on measuring the coupled rotational motion. This research has the potential to further develop understanding of in-orbit inertia estimation.
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| CT - Yale University |
http://www.yale.edu/dropteam |
| Proposal
ID: 2010-2509 |
Flight Week: June 17-26, 2010 |
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Crystalline Structure Transformation in Complex Plasma |
The study of dusty plasma is of central importance to NASA’s space science strategic enterprise, especially with regard to planetary accretion and the improvement of industrial depositional processes. Since the discovery of the crystalline structure of complex plasma in 1994, the dynamics of these complicated systems have been the focus of myriad experiments conducted on Earth, aboard the ISS, and on parabolic flight campaigns. The goal of this experiment is to image dusty plasma microgravity crystalline structure and its transformation during the continuously changing gravitational conditions of parabolic flight. A dual-camera, dual-laser system on motorized translation stages will allow the collection of images that can be analyzed using particle-tracking algorithms to determine particle spacing and Debye lengths as a function of gravitational force. This follow-up experiment incorporates vastly more reliable and easily maneuverable imaging equipment, a redesigned vacuum chamber with a stronger plasma sheath and thus a larger cloud-forming area, and the opportunity to measure plasma parameters using a Langmuir probe on the ground as well as to characterize system responses to microgravity in a drop tower facility. Our outreach activities have matured, becoming more integrated in school curricula (FIRST Robotics program) and aiming to encourage the pursuit of “outside-the-classroom” science applications.
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| FL - Embry-Riddle Aeronautical University |
http://eraumicrogravity.org |
| Proposal
ID: 2010-2493 |
Flight Week: June 17-26, 2010 |
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Project HORIZONS (Harmonic Oscillations Resulting in Zero-G On-axis Nutation of Spacecraft) |
The dynamic motion of liquid propellant and its interaction with the solid-body of the spacecraft is of paramount concern. When considering the attitude stability of the oscillating spacecraft as a whole, the sloshing movement of the liquid propellant produces a rotational instability about the vehicle’s spin axis, which could potentially lead to fatal consequences for the mission. One such fuel slosh anomaly occurred with NASA’s robotic space probe named NEAR Shoemaker. In December 1998, the first attempt of placing the satellite into orbit failed on the first of four rendezvous burns. Right after the burn sequence was initiated, it was immediately aborted which sent the satellite into a “tumble”, causing it to lose its solar orientation and battery power. More recently, another such instance occurred with the second launch of SpaceX’s Falcon I rocket. Just after launch in March of 2007, the first stage of the rocket successfully completed its burn, however, an abrupt transition to its second stage excited the liquid propellant causing fuel slosh. This disturbance lead to rapid oscillatory nutation growth which caused the rocket to lose functionality. The sloshing caused the rocket to roll, depriving the second stage of fuel and resulting in the failure of the mission. It is therefore important to understand the nature of fuel slosh and how exactly the liquid propellant behaves in order to combat these adverse outcomes.
Viscosity effects, brought about by the flow of the liquid propellant, cause the energy of the spacecraft to be converted from rotational kinetic energy to molecular kinetic energy. Since the forces and torques associated with the viscous effects are internal, there is no net effect on the angular momentum of the vehicle; there is only a change in its rotational kinetic energy. This energy dissipation, on a molecular level, will cause the spacecraft to transition about its minor axis (spin axis) to its major axis, producing an unsteady, oscillatory spin. This non-linear, time-dependant nature of fuel slosh has led to some interesting concepts to lessen the effects of the motion of liquid propellant.
At the forefront of these concepts is the application of a PMD, or a Propellant Management Device, which is anything installed within the walls of the fuel tank that directly interacts with the liquid propellant. A common PMD is a diaphragm, an elastometric material installed on the inside of a fuel tank. As the liquid propellant is expended, the diaphragm will compress inside the tank to minimize the free surface area inside of the tank directly in contact with the remaining fuel. This will lessen the ability of the fuel to retain a sufficient amount of kinetic energy with which to dissipate through the fuel tank side-walls. However, should the tank be constructed without a diaphragm (a bare tank), the dissipation of the kinetic energy impacts the system directly.
As of late, a new phenomenon has arisen for a scenario involving a bare fuel tank filled to 100% capacity. In this anomaly, with the inertia ratio of the spacecraft at 0.9, there is a phenomenon that occurs within the bare tank. NASA’s Launch Services Program asked Project HORIZONS to investigate this occurrence and report its findings to gain new insight. Therefore, Project HORIZONS proposes to conduct an additional experiment in the microgravity environment involving a bare fuel tank filled to 100% capacity with a 0.9 effective inertia ratio. The results of this experiment will be analyzed to determine the cause of this phenomenon in order to dampen its effects.
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| IN - Purdue University |
http://web.ics.purdue.edu/~mbrod/aae418 |
| Proposal
ID: 2010-2481 |
Flight Week: June 17-26, 2010 |
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Effect of Textured Surfaces on Bubble Detachment and Contact Area in Microgravity |
Flow boiling heat transfer is characterized by high heat transfer rates and minimal mass and volume requirements. Introducing flow boiling heat transfer into a microgravity environment has important applications in both spaceflight and Earth-bound systems. Flow boiling systems can be incorporated into spacecraft design to reduce the size and mass of satellites and vehicles, and can also provide the high heat transfer rates required to maintain the temperature of structures in space. In 1-g, flow boiling is used in miniature flow loops to cool high-powered electronics. In such small-scale cases, capillary forces are largely dominant over buoyancy forces, and the microgravity environment can be used to model system behavior.
Research by others has shown that heat flux is a maximum near the contact line. Thus, several research groups around the world are currently focused on developing textured heat transfer surfaces to optimize flow boiling, either by encouraging bubble detachment or by increasing bubble contact line length. By introducing textured heat transfer surfaces into flow boiling systems, heat transfer in microgravity and 1-g can be further improved.
The proposed experiment will use a flow boiling model to examine the bubble removal and the growth of bubble contact line on several of these important new textured heat transfer surfaces in microgravity. Bubble diameter at detachment and the length of the bubble contact line will be measured for each surface. As textured heat transfer surfaces are relatively new developments for 1-g flow boiling, the proposed experiment would be the first to explore the behavior of each surface in weightlessness.
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| MI - University of Michigan |
http://Website is under construction |
| Proposal
ID: 2010-2505 |
Flight Week: June 17-26, 2010 |
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Evaluating the Extendable Solar Array System in a Microgravity Environment |
The eXtendable Solar Array System (XSAS) is a modular satellite power generation system under development at the University of Michigan for use on CubeSats (a type of nanosatellite design that has been standardized by California Polytechnic State University). When fully deployed in orbit XSAS has the potential to supply up to 5-7 times more power than current CubeSat capabilities with the help of its solar panel extension of nearly 7 feet. This extension can also act as a boom to facilitate a gravity gradient stabilization system. With its modular packaging, XSAS can be easily integrated into a variety of different CubeSat missions. Our goal is to examine the deployment of the XSAS system in various tumbling conditions through a largely automated experiment. Our project will focus on the structural mechanics of XSAS and the deployment dynamics in microgravity. Our experimental variables are the ballast masses, hinge springs, latching mechanisms, and rotation rates during deployment. The rotation rates will correspond to off-design scenarios where the satellite has not fully de-tumbled in orbit before deployment. To simulate the conditions of deployment in orbit, a microgravity environment is necessary to allow the required six degrees of freedom associated with translation and rotation. We will analyze the deployment using data obtained from accelerometers, strain gauges, and cameras. This data will allow us to determine the forces, moments, and deflections on XSAS. The data that we obtain from our flight tests will be used to suggest improvements to the XSAS design and increase the Technology Readiness Level. The knowledge and data that we gain will also allow us to complete a lessons learned document for future free-float microgravity testing projects.
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| MI - University of Michigan |
http://nanofet-zestt.net |
| Proposal
ID: 2010-2492 |
Flight Week: June 17-26, 2010 |
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Exploring the Design Space of the Dry Configuration of the Nanoparticle Field Extraction Thruster in Microgravity |
The Nanoparticle Field Extraction Thruster (NanoFET) is a novel electric propulsion device under development at the University of Michigan. The NanoFET system uses micro/nano-electromechanical systems (MEMS/NEMS) to electrostatically charge and accelerate micro/nano-particles and create thrust for small satellite applications. With NanoFET, the goal is to create a single electric propulsion device that is easily throttle-able to host a large range of propulsive tasks.
ZESTT Reflight proposes to fly a NanoFET prototype to determine its performance in microgravity. Team ZESTT Reflight will take the lessons learned from the 2009 ZESTT campaign1 (M-1 prototype) and apply them to design, build, test, and fly a second generation (M-2 prototype) of NanoFET. The team will design a feedback controlled piezoelectric (piezo) based feed system to disperse particles through a charging micro-sieve. An induction charge detector (ICD) and Faraday probe are also being designed to evaluate NanoFET's performance in near space conditions – i.e., under vacuum and in microgravity. It is required that the ICD and Faraday probe have nano-Amp precision and accuracy to adequately measure the current induced by charged particles. Prior to flight, extensive ground testing will be conducted to confirm expected operation of the diagnostic tools that will be used. A baseline data set will be gathered from the M-1 thruster. Ground testing of the M-2 will also begin to characterize its performance with respect to applied electric fields, piezo actuation, and particle mass density. Microgravity tests will be used to validate ground test results as well as NanoFET theoretical models to develop the design drivers of future NanoFET generations.
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| NJ - The College of New Jersey |
http://www.tcnj.edu/~teamdpx/ |
| Proposal
ID: 2010-2468 |
Flight Week: June 17-26, 2010 |
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Analysis of Dust Particle Dynamics in a Varying Gravitational Field Part III |
While dusty plasmas are commonly found amongst astrophysical observations and within ground based fusion reactors and other devises, there is a relatively small amount of understanding regarding the dynamics and formation of the dust clouds themselves [6, 7, 13, 14, 16]. There is a great amount of interest in the effects of these dusty plasmas on ground based research, creating the need to better understand the dynamics of the dusty plasma and how to manipulate and control its motion. The field is advancing rapidly, and in an effort to explain the properties of the dusty plasmas, many devices are being brought into microgravity, where results can be obtained that cannot be recreated within the laboratory [1, 2, 10, 15, 17, 18].
The team Dusty Plasma Experiment will test the dynamics of a silica dust suspended in an argon DC-glow discharge plasma. The goal of bringing this research into microgravity is to analyze the dynamics of both the dust particles and the dust cloud itself as a function of varying gravity. The hope is that by eliminating the major force of gravity, we will be able to observe the effects of smaller forces on the dust particles, such as drag. Furthermore, most experiments with dusty plasmas in microgravity have been performed using an RF plasma, so less is known about the dynamics and properties of a DC-glow discharge plasma in microgravity. Previous work on the ‘Weightless Wonder’ produced very successful, significant results. However, not all of our goals were reached, and our experience has allowed for major adjustments in the experimental set up and procedure, fine tuning the experiment itself and the data acquisition methods. By adjusting the experiment, the Dusty Plasma Experiment III should be able to obtain data in microgravity which will lead to an understanding of the dust cloud formation and dynamics.
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| NY - NY - State University of New York at Buffalo |
http://www.ubaiaa.org/Home/micro-gravity/outreach |
| Proposal
ID: 2010-2484 |
Flight Week: June 17-26, 2010 |
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Relative Attitude Determination for Satellite Formation Flying |
Formation flying in satellites is a field of high interest in the aerospace industry. Formation flying requires a high amount of accuracy between spacecraft; the proposed method investigates concepts in relative spacecraft navigation using a formation of two satellites and a third arbitrary point. This will be performed by utilizing information provided by the visual navigation system. Using these sensors, an algorithm can be used to compare each spacecraft’s relative orientation to each other. Using a third point, each spacecraft will be able to determine its relative rotational orientation.
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| TX - Austin Community College |
http://http:www.austincc.edu/asa |
| Proposal
ID: 2010-2485 |
Flight Week: June 17-26, 2010 |
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SRED - Smart Resistive Exercise Device For Free Weight Simulation In Microgravity |
We propose to construct and test a new type of resistive exercise device which is designed to recreate, in a microgravity environment, both the resistance ( i.e., the “weight”) and the inertial properties of free weights. The device is based on a cylinder and piston arrangement whereby one side of the piston is maintained at ambient cabin pressure, while the pressure of the partial vacuum on the other side of the piston is continually re-adjusted by computerized feedback and control to mimic in all details the behavior of arbitrarily selected free weights in a normal gravitational setting. This device addresses the long standing and significant problem of muscle atrophy and bone deterioration due to lack of normal gravitational loading in space flight. The feedback and control algorithm takes input from sensors measuring pressure, acceleration, direction of motion, and applied force and calculates the pressure in the partial vacuum side of the cylinder required to produce the required simulated weight and inertial properties. Digital outputs based on the result of these calculations control solenoid valves which act to adjust the pressure in the cylinder to the targeted value.
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| TX - San Jacinto College North |
http://www.sjcd.edu/teamsoar/ |
| Proposal
ID: 2010-2519 |
Flight Week: June 17-26, 2010 |
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Further Evaluation of the Effects of Short Term Reduced Gravity on Prothrombin Time of Plasma |
Understanding how blood coagulates is important, especially in a modified environment such as microgravity. Astronauts must know what changes their vitals will undergo while in space during intricate missions, so procedures can be developed to prevent and manage accidents. The effect of microgravity on blood coagulation has been experimented indirectly by studies that examined aspects of coagulation such as plasmin degradation and assembly of fibrin clots, but more extensive research on the matter is needed to elucidate on factors that may contribute to clot time variances in reduced gravity (1, 9, 14). To date, no biochemical clotting studies have been conducted in flight (Attachment 3.0). Human knowledge of microgravity’s effect on the rate of blood clotting is crucial to astronaut safety during missions. Tests have been done using animal blood, but animal and human blood differ, and this difference, no matter how small, will lead to inadequate precaution should an astronaut be wounded in space (22, 23, 24). We know that many of the body systems slow down, organs don’t secrete as much as they normally do, and cell production is decreased, which leads us to believe blood coagulation is slowed while at reduced gravity (24). To test this hypothesis, out team plans to use human control plasma and an enzymatic blood-clotting test, the Prothrombin Time (PT) test accomplished through the Abbott ISTST analyzer already used by NASA and the air force for fluid analysis, while in flight on the C-9. This study will also be replicated on ground. As we are conducting a re-flight, we expect our data to confirm the decreased clotting activity that was suggested in 2006 (Attachment 10.0) by removing variables that compromised the experimental validity of previous student research.
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