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Viewing 61 to 90 of 61883
2004-07-19
Technical Paper
2004-01-2459
Gerard Heyenga, Louis Stodieck, Alex Hoehn, Mark Kliss, Cameron Blackford
The present suite of advanced space plant cultivation facilities require a significant level of resources to launch and maintain in flight. The facilities are designed to accommodate a broad size range of plant species and are, therefore, not configured to support the specific growth requirements of small plant species such as Arabidopsis thaliana at maximum efficiency with respect to mass and power. The facilities are equally not configured to support automated plant harvesting or tissue processing procedures, but rely on crew intervention and time. The recent reorganization of both spaceflight opportunities and allocation of limited in-flight resources demand that experiments be conducted with optimal efficiency. The emergence of A. thaliana as a dominant space flight model organism utilized in research on vegetative and reproductive phase biology provides strong justification for the establishment of a dedicated cultivation system for this species.
2004-07-19
Technical Paper
2004-01-2455
Hans-Dieter Seelig, David M. Klaus, Louis S. Stodieck, Alexander Hoehn
This study investigated the possibility of detecting water deficit stress in plants by using optical signals collected from leaves. Two theoretical approaches have been investigated. In principle, chlorophyll fluorescence can be used to measure generally stressful situations in plants. Our review, however, found that simple ratios of coarsely time-resolved chlorophyll fluorescence, such as maximum fluorescence over fluorescence at steady state, appear to be incapable of adequately distinguishing water stress from other stress factors. A second principle being investigated involves correlation of light absorption within leaves to leaf-water-content using water absorbing and non-water absorbing wavelengths. Our investigation concentrated on defining and eliminating as many extraneous variables as possible.
2004-07-19
Technical Paper
2004-01-2456
Jessica J. Prenger, Susan L. Steinberg, Daniel Haddock, Joey H. Norikane, Howard G. Levine
The WONDER space flight experiment will compare the operation of both substrate-based and porous tube nutrient delivery systems (NDS) under microgravity conditions. Each NDS will be evaluated with three moisture availability regimes, and moisture sensing will be critical for the operation and evaluation of the systems. Orbital Technologies (Madison, WI) has developed a space flight-rated temperature and moisture acquisition system (TMAS) for measuring water content of plant growth medium. The sensors were evaluated in 0.25-1 mm and 1-2 mm baked ceramic aggregate (Profile and Turface, respectively). The sensors' pooled standard deviations ranged from approximately 2% to 5% relative water content (RWC), and root mean square error between sensor RWC and measured RWC was greater than 3% using linear calibration.
2004-07-19
Technical Paper
2004-01-2453
Laurie J. Peterson, Paul D. Bolton
The NASA Orbiter was designed with the ability to store a limited amount of wastewater on board. Due to several factors including the storage capacity of the waste tank, the number of crew members onboard, and the length of a mission, the Orbiter must vent wastewater overboard at regular intervals. During a typical Orbiter mission to the International Space Station (ISS), the Orbiter must vent a significant amount of wastewater at least once during the docked timeframe. A future ISS program requirement that affects the Orbiter while docked, is elimination of wastewater venting, specifically urine, once the Japanese Experiment Module (JEM) is added to the orbiting facility. A working group was developed to address elimination of orbiter wastewater venting with members from both the Orbiter and ISS programs. Multiple options exist to meet this requirement.
2004-07-19
Technical Paper
2004-01-2434
Yu. A. Berkovich, A. N. Erokhin, S. O. Smolianina, J. J. Prenger, H. G. Levine
A cylindrical plant growth chamber (PGC) referred to as PHYTOCYCLE-SD was designed and developed as a conveyor-type cultivation system for continuous production of salad crops. The volume of the plant growth chamber is 0.19 m3, and the illuminated crop area is 0.86 m2. The PGC is comprised of a convex cylindrical planting surface with a spiral cylindrical light unit (LU) above the planting surface. The LU consists of 15 light-emitting diode (LED) panels distributed on the spiral cylindrical surface with adjustable operating currents between 10 to 35 mA. The average photosynthetic photon flux (PPF, 400–700 nm wavelengths) level at the crop surface (3 cm below the light bar) is 350 μmol m−2 s−1 and the LU power consumption is approximately 440 W. Leaf area as a function of the radius of the cylindrical growth chamber has been determined experimentally. Light intensity and distribution inside cylindrical growth chamber has been measured and modeled.
2004-07-19
Technical Paper
2004-01-2433
J. J. Maas, M. J. Mischnick
The CANDS (Circulating, Aeration, and Nutrient Delivery System) Phase II SBIR is currently developing and testing methods and procedures to control moisture, oxygen, and temperature in the root zone of a particulate based micro-gravity nutrient delivery system. The completion of the first year and a half of the CANDS Phase II SBIR has shown significant engineering developments towards environmental control of the root zone. These developments include the measurement of root zone oxygen content, characterization of forced and flood-ebb aeration rates, successful control of root zone moisture using miniature heat-pulse moisture sensors, and successful control of root zone temperature via an insulating/temperature controlling water jacket. At the conclusion of the CANDS Phase II SBIR an integrated root zone environmental control system will be constructed for integration into plant growth systems to eliminate the uncertainties that exist in current plant growth data.
2004-07-19
Technical Paper
2004-01-2437
Hiroyuki Miyajima, Tomofumi Hirosaki, Yoshio Ishikawa
A Regenerative Life Support System (RLSS) is a system that establishes self-sustained material recycling and circulation within a space base on the Moon or Mars. This is a large-scale and complicated system comprising a lot of components such as humans, plants and material circulation system. A RLSS contains many factors with uncertainty, such as dynamics of plants and humans, and failure and performance deterioration of devices. In addition, a RLSS is a large-scale and complicated system extending gradually. An environment with uncertainty or a large-scale and complicated system may not be properly addressed by a centralized system. In particular, such a system cannot always gather accurate information in one center in a frequently shifting environment, thus appropriate processing may be difficult. Therefore, we tried autonomous decentralization of information or decision-making using a Multi-Agent System (MAS).
2004-07-19
Technical Paper
2004-01-2435
Geoffrey Waters, Youbin Zheng, Danuta Gidzinski, Michael Dixon
Due to its large proportion of edible biomass, beet (Beta vulgaris) has high potential as a candidate crop for bioregenerative life support systems. This paper summarizes data collected for beet under batch and staged stand culture in closed environment chambers. Full stand trials were conducted under the following conditions: 1000 μL L−1 atmospheric carbon dioxide concentration, light intensities ranging from 400–600 μmol m−2 s−1 PAR with a 14 hour photoperiod, 73% ± 5% relative humidity, a 26/20 °C day/night temperature regime and a fixed planting density of 17.6 plants m−2. For batch planted stands, total edible yield was determined to be 28.3 g dry weight basis (dwb) with a 95% Confidence Interval (CI) of [24.7, 31.8] g plant−1 with a harvest index of 94%. Under similar conditions, yield for staged beet stands was 31.4 g dwb with a 95% CI of [24.54, 38.31] g plant−1. Water use efficiency under these same conditions was found to be 0.003 mol C mol−1 H2O.
2004-07-19
Technical Paper
2004-01-2439
Theresa Klein, Devika Subramanian, David Kortenkamp, Scott Bell
Advanced life support systems have many interacting processes and limited resources. Controlling and optimizing advanced life support systems presents unique challenges that are addressed in this paper. We have developed a controller using reinforcement learning [Barto&Sutton], which actively explores the space of possible control strategies, guided by rewards from a user specified long term objective function. We evaluated this controller using Biosim, our discrete event simulation of an advanced life support system. This simulation supports all life support modules including crew, food production, air revitalization, water recovery, solid waste incineration and power. Our algorithm for reinforcement learning discovered unobvious strategies for maximizing mission length. By exploiting nonlinearities in the simulation dynamics, the learned controller outperforms a controller designed by an expert.
2004-07-19
Technical Paper
2004-01-2438
H. Y. (Jannivine) Yeh, Cheryl B. Brown, Frank F. Jeng, Chin H. Lin, Michael K. Ewert
The development of the Advanced Life Support (ALS) Sizing Analysis Tool (ALSSAT) using Microsoft® Excel was initiated by the Crew and Thermal Systems Division (CTSD) of Johnson Space Center (JSC) in 1997 to support the ALS and Exploration Offices in Environmental Control and Life Support System (ECLSS) design and studies. It aids the user in performing detailed sizing of the ECLSS for different combinations of the ALS regenerative system technologies (1, 2). This analysis tool will assist the user in performing ECLSS preliminary design and trade studies as well as system optimization efficiently and economically.
2004-07-19
Technical Paper
2004-01-2441
Sherif Abdelwahed, Jian Wu, Gautam Biswas, John W. Ramirez, Eric J.-Manders
This paper discusses a hierarchical online fault-adaptive control approach for Advanced Life Support (ALS) Systems. ALS systems contain a number of complex interacting subsystems. To avoid complexity in the models and online analysis, diagnosis and fault-adaptive control is achieved by local units. To maintain overall performance, the problem of resource management for contending concurrent subsystems has to be addressed. We implement a control structure, where predefined set-point specifications for system operation are used to derive optimizing utility functions for the subsystem controllers. We apply this approach in situations where a fault occurs in a system, and once the fault is isolated and identified, the controllers use the updated system model to derive new set point specifications and utility functions for the faulty system.
2004-07-19
Technical Paper
2004-01-2440
Todd M. Quasny, Larry D. Pyeatt
Abstract To make extended space missions, such as missions to Mars, a reality, an advanced life support system (ALS) must be developed that is able to utilize resources to their fullest capabilities [2]. In order to make such a system a reality, a robust control system must be developed that is able to cope with the complexity of an ALS. This work applies reinforcement learning (RL), a machine learning technique, to the task of controlling the water recovery system of a simulated ALS. The RL agent learns an effective control strategy that extends the mission length to the point that lack of water is no longer the cause of mission termination.
2004-07-19
Technical Paper
2004-01-2425
Gaetana Bufano, Elena Brach Prever, Valter Perotto, Paolo Vaccaneo, Zoltan Szigetvari, Jan Persson, Johannes Witt
The Columbus ECS PFM Test was intended as the final verification of the Module Thermal Design after a series of successful tests at subsystems level (e.g. the Active Thermal Control Subsystem and the Environmental Control and Life Support System) The test campaign has been articulated as a sequence of several test cases to investigate the main thermal aspects, to prove the Module thermal design in the extreme operative conditions and to correlate the thermal mathematical model (TMM). The interpretation of test results and the correlation confirmed that the thermal design of the module is adequate, but some areas of concern remain, mainly for the difficulty to translate to 0-g the results of a complex test in 1-g environment, and for some aspects of the air and cabin loops.
2004-07-19
Technical Paper
2004-01-2430
Jon B. Holladay, Shawn E. Reagan, Greg Day
A newly developed solid-state temperature controller will offer greater flexibility in the thermal control of aerospace vehicle structures. A status of the hardware development along with its implementation on the Multi-Purpose Logistics Module will be provided. Numerous advantages of the device will also be discussed with regards to current and future flight vehicle implementations.
2004-07-19
Technical Paper
2004-01-2432
Yuichiro Takai, Kazutaka Miyatake, Kunishi Miyoshi, Yas Takashima
The efficiency and output of commercial agricultural as it exists today is greatly influenced by natural environmental conditions. Production under a controlled environment such as a Vegetable Factory concept may be considered to overcome these problems. The Modular Growing Component Salad Machine (MGCSM), which was built in 1992, has recently undergone major design changes. Use of red and blue LEDs are being considered to replace high-pressure sodium (HPS) lamps. This modification can reduce mass, weight and energy consumption. If this growing system can be manufactured at an affordable cost to be used for profitable agricultural production on Earth for growing flavorful, pesticide free, healthier vegetables with minimal labor requirements.
2004-11-02
Technical Paper
2004-01-3089
Lionel D. Alford, Aaron Altman
The typical aeronautical engineering approach to low Reynolds number flight studies has been to start with known high Reynolds number aerodynamic paradigms and attempt to match them by scaling to observations of birds and insects. On the other hand, the typical biological approach to natural flight aerodynamics has been to try to fit the observations of birds and insects into the typical known aerodynamic paradigms. Neither of these approaches has met with much success, and although we know more about the potential processes of natural flight, we have not been able to describe them using the framework of conventional aerodynamics. The investigation of low Reynolds number aerodynamic flows at the University of Dayton has led to a proposed new method of characterizing and describing the aerodynamics of natural flight. Lift in natural flight is theorized to be based in the spanwise flow along the curvature of a flapping wing.
2004-11-02
Technical Paper
2004-01-3088
J. Philip Barnes
The flight mechanics of dynamic soaring are described to explain how the albatross can sustain soaring flight over a waveless sea in any net direction, including upwind, by extracting energy from the wind velocity gradient with cyclic zoom maneuvers. A dynamic soaring force is postulated to be represented by a wind-aligned vector providing energy gain during both upwind ascent and downwind descent in the wind profile. Maneuver angles are specified consistent with both a dynamic soaring rule and the desired net progress over the water. The equations of motion for coordinated maneuvering in the wind profile are derived and numerically integrated for a range of trajectories as perceived by the albatross, and also as perceived by a stationary observer.
2004-11-02
Technical Paper
2004-01-3092
Zenovy S. Wowczuk, Kenneth H. Means, Victor H. Mucino, Gregory J. Thompson, James Smith, Jeffery R.X Auld, James E. Smith, Adam Naternicola, Lawrence Anthony Feragotti, Bruce J. Corso
The development of a standardized roll-on, roll-off (RoRo) sensor pallet system for a C-130 aircraft was conceived by the National Guard and the Counter Narco-Terrorism Technology Development Office to assist in counterdrug reconnaissance activities within the United States and surveillance and reconnaissance missions worldwide. West Virginia University was contracted to perform the design and development of this system because of their innovative design ideas. Before development, the design parameters were established by these two DoD agencies, their mission requirements and by the limitations of the C-130 aircraft. These limitations include using Commercial off the Shelf (COTS) and Government off the Shelf (GOTS) items when developing the system that must be universal on all C-130 aircrafts variants B thru H. Further design criteria are by the limitations of the C-130 aircraft and its existing mission requirements.
2004-10-18
Technical Paper
2004-21-0001
Richard C. Lind, Huan W. Yen, Douglas L. Welk
The evolution of car radio in the past seven decades is a perfect illustration of the convergence of diverse technical fields: RF electronics, mobile wireless communications, the Internet, personal computers, consumer electronics, and automotive human machine interfaces. The early part of the radio evolution was driven by the need to improve the received audio signal quality while in the past two decades the driver has been to increase the channel capacity and to enhance the degree of personalization. Besides traditional AM/FM programming, today's radios also play a variety of media such as cassette tape, CD, MP3, DVD-A etc. as well as over 100 channels of satellite digital audio programs. Going forward, we believe that the radio will continue to be the entertainment center of the vehicle, and that the consumers are expecting to have access to personalized information anywhere and anytime.
2004-10-18
Technical Paper
2004-21-0006
Lawrence C. Pesce
In the spring of 1991, the business teams of Hughes Communication and Thomson Consumer Electronics asked the question of whether a satellite TV system with an 18″ dish could be a viable consumer product. Would people pay for what was previously “free” and could the market be expanded from the rural un-served to the perceived metro underserved? Betting that consumers would pay for higher quality and more compelling entertainment, the dice was rolled. That bet more than paid off with the satellite TV industry growing to more than twenty million subscribers. Satellite radio now faces the same questions, but history has already passed judgment on its ultimate success. The question is no longer whether it will succeed, but exactly how great is the opportunity. Satellite radio will not only fulfill its promise of offering a wide range of lean back entertainment options, but also the potential for new lean forward services.
2004-11-16
Technical Paper
2004-01-3315
Alexandre de Almeida Guimarães
It is clearly perceived the exponential growth of on-board electronics on several technological segments. On aerospace segment that is not different. Besides those propulsion and navigation fundamentals systems, necessary on most part of the aircrafts, many complex electronic systems are required: for the treatment of information sent by either landed equipments or other aircrafts (often found on military applications), and for comfort and entertainment systems (most related to passenger transportation applications). In any case, the amount of available and exchangeable information between these systems is fairly huge. Such data exchange would be easier performed if were made through the application of a communication protocol. This paper lists and analyses the communication protocols used by most part of the current and future aircrafts. The intention of this document is to be a study guideline of avionics related protocols.
2004-11-16
Technical Paper
2004-01-3348
Marcelo R.A.C. Tredinnick, Marcelo Lopes de Oliveira e Souza
In this work we study the stability of digital controls of flexible/Vibratory aerospace/automobile systems by the graph norm technique, occurring in sampled-data control systems due to sampling period variations. To do so, this work tries to establish regions (graphs) of stability and instability in a Banach Space, the distances (norms) between them and a given design to detect analytically and/or numerically its margins of stability or conditions of instability. Based on that, we sketch the first steps for a design methodology of stable digital controllers of flexible/vibratory systems embedded in a sampled-data system with adjustable sampling periods of A/D and D/A converters. A short tutorial about the graph norm technique is also given and some theoretical results as well numerical results are shown. This work was done in two folds to unmask the stability secrets hidden in a general sampled-data control system, until today not revelated.
2004-11-16
Technical Paper
2004-01-3415
Marcelo Lopes de Oliveira e Souza, Gilberto da Cunha Trivelato
In this work we discuss some types of simulation environments and laboratories, their characteristics and applications to the simulation and control of aerospace vehicles. This includes: the basic definitions, types and characteristics of simulators and simulations (physical, computational, hybrid, etc.; discrete events, discrete time, continuous time, etc; deterministic, stochastic, etc.) their basic compromise (simplicity × fidelity), their man-machine interfaces and interactions (virtual, constructive, live, etc.), their evolution law (time, events, mixed, etc.), their architectures (“stand-alone”, PIL, HIL, MIL, DIS, HLA, etc.), and especially, their environments (discrete, continuous, hybrid, etc.) and laboratories (physical, computational, hybrid, etc.), and their applications to the simulation and control of aerospace vehicles. This is illustrated by some examples driven from the aerospace industry.
2004-11-16
Technical Paper
2004-01-3474
Paulo Henriques Iscold Andrade de Oliveira, Rogério Pinto Ribeiro, Ricardo Luiz Utsch de Freitas Pinto, Luciano Saraiva Resende, Fabrizio Nicolosi, Domenico Pietro Coiro, Nicola Genito
This paper present the instrumentation procedure used in order to determine the performance, stability and control characteristics of the light aircraft CEA-205 CB-9 Curumim. The instrumentation used is: i) autonomous acquisition system using micro controllers; ii) solid state inertial platform; iii) pitot probe; iv) attack and sideslip angle indicators; v) potentiometer on control system; vi) load cell on control system; vii) propeller tachometer; viii) barometer; ix) thermometer and x) GPS. Assembly and calibration detail procedures are presented with some results obtained on typical maneuvers. This work, in development on the Center for Aeronautical Studies of Federal University of Minas Gerais (CEA/UFMG) and on the Department of Aeronautical Engineering of Naples University (DPA), intend to assembly a system in order to perform low cost flight tests on light aircrafts.
2004-11-16
Technical Paper
2004-01-3472
Paulo Henriques Iscold Andrade de Oliveira, Ricardo Luiz Utsch de Freitas Pinto
This paper presents a numerical process for determination of optimal flight paths for competition soaring. The issue is reduction of flight time in order to soar towards an ascending thermal and climb, through thermal flying, to the initial altitude. The optimization procedure consists in the application of a Direct Method in order to obtain suboptimal solutions through parameterization of state variables, unlike a previous study by the same authors which was based on control parameterization. A mathematical programming procedure is used in order to determine the sub-optimal values for the parameterized state variables. The optimal control law, which is necessary for the generation of the sub-optimal state, is obtained through a step by step penalty technique. The obtained results demonstrate that the optimization of transitory phases is important for the minimization of total flight time.
2004-07-19
Technical Paper
2004-01-2349
Yasuhiro Tako, Shou-ichi Tsuga, Ryuji Arai, Takashi Tani, Go Honda, Keiji Nitta
Closed habitation experiments are to be carried out using Closed Ecology Experiment Facilities (CEEF) from FY2005 to FY2009. The last target of duration of closed habitation is four months. Preliminary study and testing have been conducted in order to carry out the closed habitation experiments. The CEEF has three closed plantation chambers (PC-A, B and C) with artificial lighting solely having each cultivation area of 30 m2 and a closed plantation chamber (PC-F) with both natural lighting and supplemental artificial lighting having a 60-m2 cultivation area. A ‘stable’ period of sequential crop cultivation was maintained for four weeks in a trial experiment conducted in FY2003 using the Plantation Module (PM), in which rice, soybean and crops including rice sapling, soybean sapling, soybean, peanuts and safflower were cultivated in PC-A, PC-B, PC-C and PC-F, respectively. Amount of total clean water input to PM was 741 L day−1 on the average for the period.
2004-07-19
Technical Paper
2004-01-2355
Yas Takashima
An Efficient Growing System is always in need for both terrestrial and extraterrestrial environments. The Multi-layered Hydroponics Growing System (MHGS) was developed and tested as a potential commercial scale production system for leaf crops. Six crops of Bibb lettuce (Lactuca sativa, Cultivars Butter Crunch) was grown successfully with a 40 percent shade cloth to diffuse light intensity, which helped to improve quality and palatability. At the same time the Overhead Hydroponics Growing System (OHGS) was developed for growing cucumber (Cucumis sativus L. Cultivar- Summer dance) with apical shoots slightly angled upward to give orientation of growth direction while enhancing lateral branch growth. Bib lettuce can be grown by utilizing the diffused light provided by the cucumber grown above, eliminating the need for the shade cloth.
2004-07-19
Technical Paper
2004-01-2354
Kazutaka Miyatake, Kazumi Kobayashi, Yas Takashima, Masaaki Suzuki
The use of Superheated Steam (SHS) has been known for nearly 100 years. Utilization of SHS has been limited due to lack of technological development and knowledge about its potential application. SHS is achieved by heating the saturated steam to temperatures exceeding 100° C. This research was conducted to investigate the multipurpose applications of superheated steam particularly for cooking, which is an area lacking in technological developments. Even under normal or hypo baric conditions, high thermal energy from combined latent and superheat generated from a carbon-heating element controlled by varying electromagnetic induction. Multiple applications includes instrument sterilization, sterilization and deodorization of air, material recovery, removal of contaminants, induction of chemical reactions and cooking.
2004-07-19
Technical Paper
2004-01-2366
Marc M. Cohen
This paper presents a preliminary modeling method, Habitat Multivariate Design Model (HMVDM), to estimate the volume, size, shape, and configuration required for the design of a space habitat. The specific habitat used for this analysis is the “Habot” mobile lunar base concept. The HMVDM methodology begins with values for mass and volume from quantitative summation tools such as the NASA Office of Biological and Physical Research (OBPR) Crew Accommodations Guide. From these tools, it derives a more detailed analysis of mass and particularly of volume. The estimated volume is input into the model, written as a spreadsheet-based analytical modeling tool. In this pilot study, the diameter of a cylindrical module serves as the single independent variable.
2004-07-19
Technical Paper
2004-01-2369
Jan Osburg
The preparation of manned space exploration missions beyond Earth orbit requires precursor activities such as integrated space mission simulations at dedicated Earth-based analog facilities. In recent years, the Mars Society, with the support of private donors, has built several of these facilities. The lessons learned by the crews simulating planetary exploration activities on board those stations are generating a body of knowledge that can make a significant contribution to the design and operation of future planetary bases, as well as improve the next generation of such simulation facilities. Drawing from the author’s first-hand experience as a crewmember during the 2003 field season at the Flashline Mars Arctic Research Station, the Mars Society’s analog simulation facility on Devon Island in the Canadian High Arctic, this paper provides a compilation and first analysis of the crew’s experience.
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