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At least 955 records · Page 53

Multispectral Image Processing for Plants

The development of a machine vision system to monitor plant growth and health is one of three essential steps towards establishing an intelligent system capable of accurately assessing the state of a controlled ecological life support system for long-term space travel. Besides a network of sensors, simulators are needed to predict plant features, and artificial intelligence algorithms are needed to determine the state of a plant based life support system. Multispectral machine vision and image processing can be used to sense plant features, including health and nutritional status.

Miles, Gaines E.↗

Exploration Life Support Technology Development for Lunar Missions

Exploration Life Support (ELS) is one of NASA's Exploration Technology Development Projects. ELS plans, coordinates and implements the development of new life support technologies for human exploration missions as outlined in NASA's Vision for Space Exploration. ELS technology development currently supports three major projects of the Constellation Program - the Orion Crew Exploration Vehicle (CEV), the Altair Lunar Lander and Lunar Surface Systems. ELS content includes Air Revitalization Systems (ARS), Water Recovery Systems (WRS), Waste Management Systems (WMS), Habitation Engineering, Systems Integration, Modeling and Analysis (SIMA), and Validation and Testing. The primary goal of the ELS project is to provide different technology options to Constellation which fill gaps or provide substantial improvements over the state-of-the-art in life support systems. Since the Constellation missions are so challenging, mass, power, and volume must be reduced from Space Shuttle and Space Station technologies. Systems engineering analysis also optimizes the overall architecture by considering all interfaces with the life support system and potential for reduction or reuse of resources. For long duration missions, technologies which aid in closure of air and water loops with increased reliability are essential as well as techniques to minimize or deal with waste. The ELS project utilizes in-house efforts at five NASA centers, aerospace industry contracts, Small Business Innovative Research contracts and other means to develop advanced life support technologies. Testing, analysis and reduced gravity flight experiments are also conducted at the NASA field centers. This paper gives a current status of technologies under development by ELS and relates them to the Constellation customers who will eventually use them.

Ewert, Michael K.↗

Characterization of a Regenerable Impactor Filter for Spacecraft Cabin Applications

Regenerable filters will play an important role in human exploration beyond low-Earth orbit. Life Support Systems aboard crewed spacecrafts will have to operate reliably and with little maintenance over periods of more than a year, even multiple years. Air filters are a key component of spacecraft life support systems, but they often require frequent routine maintenance. Bacterial filters aboard the International Space Station require almost weekly cleaning of the pre-filter screen to remove large lint debris captured in the microgravity environment. The source of the airborne matter which is collected on the filter screen is typically from clothing fibers, biological matter (hair, skin, nails, etc.) and material wear. Clearly a need for low maintenance filters requiring little to no crew intervention will be vital to the success of the mission. An impactor filter is being developed and tested to address this need. This filter captures large particle matter through inertial separation and impaction methods on collection surfaces, which can be automatically cleaned after they become heavily loaded. The impactor filter can serve as a pre-filter to augment the life of higher efficiency filters that capture fine and ultrafine particles. A prototype of the filter is being tested at the Particulate Filtration Laboratory at NASA Glenn Research Center to determine performance characteristics, including particle cut size and overall efficiency. Model results are presented for the flow characteristics near the orifice plate through which the particle-laden flow is accelerated as well as around the collection bands.

air filters↗

Physical/chemical closed-loop life support

Information on physical/chemical closed-loop life support systems are given in viewgraph form. Information is given on program objectives, the elements of a life support system, and Pathfinder program elements.

Lawless, James G.↗

Disinfection of Spacecraft Potable Water Systems by Passivation with Ionic Silver

Microbial growth is common on wetted surfaces in spacecraft environmental control and life support systems despite the use of chemical and physical disinfection methods. Advanced control technologies are needed to limit microorganisms and increase the reliability of life support systems required for long-duration human missions. Silver ions and compounds are widely used as antimicrobial agents for medical applications and continue to be used as a residual biocide in some spacecraft water systems. The National Aeronautics and Space Administration (NASA) has identified silver fluoride for use in the potable water system on the next generation spacecraft. Due to ionic interactions between silver fluoride in solution and wetted metallic surfaces, ionic silver is rapidly depleted from solution and loses its antimicrobial efficacy over time. This report describes research to prolong the antimicrobial efficacy of ionic silver by maintaining its solubility. Three types of metal coupons (lnconel 718, Stainless Steel 316, and Titanium 6AI-4V) used in spacecraft potable water systems were exposed to either a continuous flow of water amended with 0.4 mg/L ionic silver fluoride or to a static, pre-treatment passivation in 50 mg/L ionic silver fluoride with or without a surface oxidation pre-treatment. Coupons were then challenged in a high-shear, CDC bioreactor (BioSurface Technologies) by exposure to six bacteria previously isolated from spacecraft potable water systems. Continuous exposure to 0.4 mg/L ionic silver over the course of 24 hours during the flow phase resulted in a >7-log reduction. The residual effect of a 24-hour passivation treatment in 50 mg/L of ionic silver resulted in a >3-log reduction, whereas a two-week treatment resulted in a >4-log reduction. Results indicate that 0.4 mg/L ionic silver is an effective biocide against many bacteria and that a prepassivation of metal surfaces with silver can provide additional microbial control.

Birmele, Michele N.↗

A 'breadboard' biomass production chamber for CELSS

The Breadboard Project of the Controlled Ecological Life Support System (CELSS) Program is the first attempt by NASA to integrate the primary components of a bioregenerative life support system into a functioning system. The central component of this project is a Biomass Production Chamber (BPC). The BPC is under construction, and when finished will be sealed for the study of the flux of gases, liquids, and solids through the production module of a CELSS. Features of the CELSS breadboard facility will be covered as will design requirements for the BPC. Cultural practices developed for wheat for the BPC wil be discussed.

Prince, Ralph P.↗

Human life support during interplanetary travel and domicile. V - Mars expedition technology trade study for solid waste management

A model has been developed for NASA to quantitatively compare and select life support systems and technology options. The model consists of a modular, top-down hierarchical breakdown of the life support system into subsystems, and further breakdown of subsystems into functional elements representing individual processing technologies. This paper includes the technology trades for a Mars mission, using solid waste treatment technologies to recover water from selected liquid and solid waste streams. Technologies include freeze drying, thermal drying, wet oxidation, combustion, and supercritical-water oxidation. The use of these technologies does not have any significant advantages with respect to weight; however, significant power penalties are incurred. A benefit is the ability to convert hazardous waste into a useful resource, namely water.

Ferrall, Joe↗

xEMU Thermal Vacuum Testing Overview

The Exploration Extravehicular Mobility Unit (xEMU) project was the culimation of over a decade of spacesuit development that was performed in-house at the NASA Johnson Space Center. This project reached a level where almost fully completed development fidelity spacesuits had been designed, assembled and tested in an integrated configuration. The xEMU Development-Verification-Test (DVT) hardware was assembled into two different xEMU test articles and underwent a series of thermal-vacuum tests at the Johnson Space Center’s Chamber B. These tests not only gathered data on thermal performance, but also exercised the life support system, communication system, suit information systems, and suit avionics. This complex test has and will continue to produce many meaningful reports ranging from component level test results (for example on spacesuit boots), test design of heater cages to simulate thermal environments for a spacesuit test article, and higher level thermal performance of subsystems (such as the Portable Life Support System) or the entire assembly. This paper provides an overview of the test configuration and also top level results from this highly successful integrated test of the xEMU.

PLSS↗

A Simulation Based Investigation of High Latency Space Systems Operations

This study was the first in a series of planned tests to use physics-based subsystem simulations to investigate the interactions between a spacecraft's crew and a ground-based mission control center for vehicle subsystem operations across long communication delays. The simulation models the life support system of a deep space habitat. It contains models of an environmental control and life support system, an electrical power system, an active thermal control systems, and crew metabolic functions. The simulation has three interfaces: 1) a real-time crew interface that can be use to monitor and control the subsystems; 2) a mission control center interface with data transport delays up to 15 minute each way; and 3) a real-time simulation test conductor interface used to insert subsystem malfunctions and observe the interactions between the crew, ground, and simulated vehicle. The study was conducted at the 21st NASA Extreme Environment Mission Operations (NEEMO) mission. The NEEMO crew and ground support team performed a number of relevant deep space mission scenarios that included both nominal activities and activities with system malfunctions. While this initial test sequence was focused on test infrastructure and procedures development, the data collected in the study already indicate that long communication delays have notable impacts on the operation of deep space systems. For future human missions beyond cis-lunar, NASA will need to design systems and support tools to meet these challenges. These will be used to train the crew to handle critical malfunctions on their own, to predict malfunctions and assist with vehicle operations. Subsequent more detailed and involved studies will be conducted to continue advancing NASA's understanding of space systems operations across long communications delays.

Li, Zu Qun↗

A Simulation Based Investigation of High Latency Space Systems Operations

This study was the first in a series of planned tests to use physics-based subsystem simulations to investigate the interactions between a spacecraft's crew and a ground-based mission control center for vehicle subsystem operations across long communication delays. The simulation models the life support system of a deep space habitat. It contains models of an environmental control and life support system, an electrical power system, an active thermal control system, and crew metabolic functions. The simulation has three interfaces: 1) a real-time crew interface that can be use to monitor and control the subsystems; 2) a mission control center interface with data transport delays up to 15 minute each way; and 3) a real-time simulation test conductor interface used to insert subsystem malfunctions and observe the interactions between the crew, ground, and simulated vehicle. The study was conducted at the 21st NASA Extreme Environment Mission Operations (NEEMO) mission. The NEEMO crew and ground support team performed a number of relevant deep space mission scenarios that included both nominal activities and activities with system malfunctions. While this initial test sequence was focused on test infrastructure and procedures development, the data collected in the study already indicate that long communication delays have notable impacts on the operation of deep space systems. For future human missions beyond cis-lunar, NASA will need to design systems and support tools to meet these challenges. These will be used to train the crew to handle critical malfunctions on their own, to predict malfunctions, and to assist with vehicle operations. Subsequent more detailed and involved studies will be conducted to continue advancing NASA's understanding of space systems operations across long communications delays.

Li, Zu Qun↗

xEMU Thermal Vacuum Testing Overview

The Exploration Extravehicular Mobility Unit (xEMU) project was the culimation of over a decade of spacesuit development that was performed in-house at the NASA Johnson Space Center. This project reached a level where almost fully completed development fidelity spacesuits had been designed, assembled and tested in an integrated configuration. The xEMU Development-Verification-Test (DVT) hardware was assembled into two different xEMU test articles and underwent a series of thermal-vacuum tests at the Johnson Space Center’s Chamber B. These tests not only gathered data on thermal performance, but also exercised the life support system, communication system, suit information systems, and suit avionics. This complex test has and will continue to produce many meaningful reports ranging from component level test results (for example on spacesuit boots), test design of heater cages to simulate thermal environments for a spacesuit test article, and higher level thermal performance of subsystems (such as the Portable Life Support System) or the entire assembly. This paper provides an overview of the test configuration and also top level results from this highly successful integrated test of the xEMU.

PLSS↗

ECLSS Does Not Exist in a Vacuum: Integrated Analysis is Necessary to Inform System Architecture Decisions

Environmental Control and Life Support System (ECLSS) architecture selection has profound implications for mission cost and mass extending far beyond the ECLSS itself. Similarly, other mission architecture decisions – particularly involving transportation systems – can influence optimal ECLSS architectures. Loop closure influences requirements for water, oxygen, and other consumables. System maintainability and reliability influences spares mass and risk. System, consumables, and spares mass interact with transportation system architectures and propellant demands and propulsion element sizing. All these interactions with other systems must be considered when evaluating ECLSS options. Analyses that focus only on maximizing ECLSS loop closure – or minimizing ECLSS mass, or minimizing ECLSS life cycle cost – may lead to sub-optimal or even counterproductive system architecture and investment decisions at the mission level. For example, an ECLSS architecture that minimizes ECLSS lifecycle cost but results in excessively high logistics mass could lead to significantly increased transportation system costs or make interplanetary transportation infeasible. Increased loop closure could result in higher development costs and higher mass if system/spares mass increases outweigh consumables reduction. In addition, systems mass and consumables mass are not directly comparable and have different impacts on propellant requirements, as consumables mass changes over the course of the mission. This paper presents an integrated analysis examining the overall impact of different ECLSS and transportation architectures on mass for a crewed Mars mission, including the habitat and transportation systems as well as consumables, spares, and propellant. Key observations are discussed, along with opportunities for further sensitivity analysis and model development. Overall, ECLSS development activities must consider their impacts at the mission level, as part of an integrated system, rather than in isolation.

Systems Analysis↗

Cryogenic Oxygen Storage Modules with Carbon Dioxide Sequestration for Environmental Control and Life Support Applications

NASA Kennedy Space Center engineers developed a Cryogenic Oxygen Storage Module (COSM) to store oxygen in solid-state form and deliver it as a gas to an end-use environmental control and/or life support system. Additionally, the COSM can scrub out nuisance or containment gases such as carbon dioxide and/or water vapor in conjunction with supplying oxygen, forming a synergistic system when used in a closed-loop application. Closed-loop life support systems require both oxygen supply and removal of toxic or nuisance gases such as CO2 from the breathing loop. In most deployed systems, these two requirements are accomplished independently. COSM combines these capabilities to work simultaneously which may allow for reduced system volume, mass, complexity and cost of a rebreathing device.

Jeffrey A Kohler↗

Wheat response to differences in water and nutritional status between zeoponic and hydroponic growth systems

Hydroponic culture has traditionally been used for controlled environment life support systems (CELSS) because the optimal environment for roots supports high growth rates. Recent developments in zeoponic substrate and microporous tube irrigation (ZPT) also offer high control of the root environment. This study compared the effect of differences in water and nutrient status of ZPT or hydroponic culture on growth and yield of wheat (Triticum aestivum L. cv. USU-Apogee). In a side-by-side test in a controlled environment, wheat was grown in ZPT and recirculating hydroponics to maturity. Water use by plants grown in both culture systems peaked at 15 to 20 L m-2 d-1 up to Day 40, after which it declined more rapidly for plants grown in ZPT culture due to earlier senescence of leaves. No consistent differences in water status were noted between plants grown in the two culture systems. Although yield was similar, harvest index was 28% lower for plants grown in ZPT than in hydroponic culture. Sterile green tillers made up 12 and 0% of the biomass of plants grown in ZPT and hydroponic culture, respectively. Differences in biomass partitioning were attributed primarily to NH4-N nutrition of plants grown in ZPT compared with NO3-N in hydroponic nutrient solution. It is probable that NH4-N-induced Ca deficiency produced excess tillering and lower harvest index for plants grown in ZPT culture. These results suggest that further refinements in zeoponic substrate would make ZPT culture a viable alternative for achieving high productivity in a CELSS.

NASA Center JSC↗

Integrated ECLSS Ground Testbed Development and Status for 2025

The reliability of Spacecraft Life Support systems and the associated mass needed to support human spaceflight is one of the largest risks for missions beyond Low Earth Orbit. The reliability of these systems directly corresponds to the number of spares needed to support the mission. Performance improvements for these systems can reduce the consumables needed for long-duration missions. The only integrated spacecraft regenerative Life Support System exists in Low Earth Orbit. It is not practical to use the ISS system to fully understand the reliability of the technology as these systems are currently maintaining a livable environment and crew’s lives are dependent on the availability of these systems. To achieve advancement on reliability and mass, NASA has initiated the development of an Integrated ECLSS ground Testbed. This paper will provide a status on the testbed development, hardware development and areas for investigation. This paper will also cover planned testbed integration and support for Earth Independent Operations (EIO). This paper will be relevant to sessions: 205, 300, 301, 404, 406, 500, 50, 506, and 511.

Christopher Brown↗

Engineering concepts for inflatable Mars surface greenhouses

A major challenge of designing a bioregenerative life support system for Mars is the reduction of the mass, volume, power, thermal and crew-time requirements. Structural mass of the greenhouse could be saved by operating the greenhouse at low atmospheric pressure. This paper investigates the feasibility of this concept. The method of equivalent system mass is used to compare greenhouses operated at high atmospheric pressure to greenhouses operated at low pressure for three different lighting methods: natural, artificial and hybrid lighting. c2004 COSPAR. Published by Elsevier Ltd. All rights reserved.

NASA Discipline Life Support Systems↗