Results for “eclss” | Engineering Papers

NASA NTRS1990

ECLSS Integration Analysis: Advanced ECLSS Subsystem and Instrumentation Technology Study for the Space Exploration Initiative

In his July 1989 space policy speech, President Bush proposed a long range continuing commitment to space exploration and development. Included in his goals were the establishment of permanent lunar and Mars habitats and the development of extended duration space transportation. In both cases, a major issue is the availability of qualified sensor technologies for use in real-time monitoring and control of integrated physical/chemical/biological (p/c/b) Environmental Control and Life Support Systems (ECLSS). The purpose of this study is to determine the most promising instrumentation technologies for future ECLSS applications. The study approach is as follows: 1. Precursor ECLSS Subsystem Technology Trade Study - A database of existing and advanced Atmosphere Revitalization (AR) and Water Recovery and Management (WRM) ECLSS subsystem technologies was created. A trade study was performed to recommend AR and WRM subsystem technologies for future lunar and Mars mission scenarios. The purpose of this trade study was to begin defining future ECLSS instrumentation requirements as a precursor to determining the instrumentation technologies that will be applicable to future ECLS systems. 2. Instrumentation Survey - An instrumentation database of Chemical, Microbial, Conductivity, Humidity, Flowrate, Pressure, and Temperature sensors was created. Each page of the sensor database report contains information for one type of sensor, including a description of the operating principles, specifications, and the reference(s) from which the information was obtained. This section includes a cursory look at the history of instrumentation on U.S. spacecraft. 3. Results and Recommendations - Instrumentation technologies were recommended for further research and optimization based on a consideration of both of the above sections. A sensor or monitor technology was recommended based on its applicability to future ECLS systems, as defined by the ECLSS Trade Study (1), and on whether its characteristics were considered favorable relative to similar instrumentation technologies (competitors), as determined from the Instrumentation Survey (2). The instrumentation technologies recommended by this study show considerable potential for development and promise significant returns if research efforts are invested.

Source record↗

NASA NTRS1993

Systems analysis of a closed loop ECLSS using the ASPEN simulation tool. Thermodynamic efficiency analysis of ECLSS components

Our first goal in this project was to perform a systems analysis of a closed loop Environmental Control Life Support System (ECLSS). This pertains to the development of a model of an existing real system from which to assess the state or performance of the existing system. Systems analysis is applied to conceptual models obtained from a system design effort. For our modelling purposes we used a simulator tool called ASPEN (Advanced System for Process Engineering). Our second goal was to evaluate the thermodynamic efficiency of the different components comprising an ECLSS. Use is made of the second law of thermodynamics to determine the amount of irreversibility of energy loss of each component. This will aid design scientists in selecting the components generating the least entropy, as our penultimate goal is to keep the entropy generation of the whole system at a minimum.

Chatterjee, Sharmista↗

NASA NTRSDate not supplied

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↗

NASA NTRSDate not supplied

Regenerative ECLSS and Logistics Analysis for Sustained Lunar Surface Missions

As NASA begins to develop concepts for sustained crew missions to the lunar surface, it will be essential to evaluate the logistics requirements needed to enable such missions. Lunar surface missions will involve crews of four astronauts living on the surface for periods of 30 days or longer. Astronauts will either live in a surface habitat or transfer between a habitat and a pressurized rover. The amount of logistics that must be delivered to the surface to support the crew, support the surface systems, and conduct science could be substantial. Because NASA plans to conduct these missions on an annual basis, the complexity and cost of logistics delivery will likely drive campaign sustainability. The amount of required logistics is partially a function of the ECLSS system in the habitable elements on the surface. The higher the capability of regenerative ECLSS that can be accommodated, the lower the logistics requirements. However, the increased regenerative ECLSS capabilities will also increase the initial delivery mass of elements and require additional maintenance and spares to maintain the systems. This paper describes an effort to evaluate lunar sustained logistics requirements, including sensitivity analysis for ECLSS architecture options and their impact on requirements. The authors determine logistics requirements using an integrated surface ECLSS model. The model considers different configurations of rover and habitat setups with multiple ECLSS options on both. The tool can also model gas and liquid transfer options between the habitat and the rover. The authors use the model to evaluate several different ECLSS configurations and their logistics requirements. The authors then complete a sensitivity analysis that compares logistic requirements and the initial delivery mass over increasing ECLSS capabilities. Finally, the authors make recommendations for an ECLSS architecture option that balances the tradeoffs between logistics requirements and ECLSS mass.

Environmental Control and Life Support↗

NASA NTRS1988

Status of the US Space Station ECLSS and internal TCS

The U.S. Space Station includes many elements and systems. Responsibility for these have been delegated to four NASA centers via a work packaging concept. Marshall Space Flight Center (MSFC) is responsible for work package one (WPOI) which includes the habitation, laboratory modules, the logistic carrier elements, as well as the environmental control and life support system (ECLSS), the internal thermal control system (ITCS), and the internal audio and video systems. Current status of the ECLSS and internal thermal are the subjects of this paper. The ECLSS is composed of six subsystem groups: the temperature humidity control, the atmosphere control and supply, the air revitalization, water reclamation and management, fecal waste management, and the fire detection and suppression subsystems. The internal TCS consists of all WP01 elements of passive and active thermal measures. The ECLSS and ITCS provide services for the permanently orbiting pressurized modules as well as the pressurized and unpressurized logistics carriers. The logistics carriers are used as ground-to-station ferries for both resupply and initial delivery of selected new equipment and later replacement items. Equipment, which cannot be subjected to the rigors of the space environment, will be carried in the pressurized logistic carrier; while an unpressurized carrier is used to resupply other commodities, such as external fluid consumables. The laboratory module houses the equipment for both payloads and subsystem maintenance and repair. The habitation module is dedicated to providing living and sleeping quarters including a galley, sleeping provisions, hygiene facilities, medical services as well as services for exercise and relaxation. The four nodes that join the two modules at their ends also house electronics as well as work stations and outside viewing cupolas. The airlocks, one providing an emergency hyperbaric chamber capability, are also attached. This assembly constitutes the U.S. provided portion of the initial station. Additional international modules and docking provisions for future attached pressurized payload as well as dual logistic module and growth capabilities are also provided. The primary heat rejection mechanism is achieved via a central set of radiators provided by another work package. The interface with the central TCS at the module heat exchangers defines the active control interface boundary of the ITCS with the central TCS. All internal cooling of the permanent orbital elements are provided via internal active fluid loops within the elements utilizing water as the transport media. Cabin and equipment cooling are provided by forced air flow and cold plate heat sinks. A special active cooling loop is provided in the laboratory module to accommodate experiments and other payloads. Coatings and insulation are used in conjunction with the active components to passively limit heat losses/gains. The most challenging ECLSS new technology issues relate to oxygen and water recovery. Closure of the oxygen loop requires the use of new regenerative CO 2 removal and concentration techniques, CO 2 reduction to convert the CO 2 to water with a waste by-product, and the electrolysis of water to produce breathing oxygen for water recovery. For water recovery three separate loops are currently planned. One loop provides potable water by utilizing a combination of recovered condensate and CO 2 reduction water. A second loop purifies hygiene water from waste from the showers, clothes washer, hygiene/hand wash stations and a dishwasher. The third loop provides hygiene water by the reclamation and purification of urine water. This paper outlines the basic services provided by the ECLSS and ITCS and describes the ECLSS functional distribution throughout the pressurized assembly.

R. Humphries↗

NASA NTRS1999

International Space Station ECLSS Technical Task Agreement Summary Report

This Technical Memorandum provides a summary of current work accomplished under Technical Task Agreement (TTA) by the Marshall Space Flight Center (MSFC) regarding the International Space Station (ISS) Environmental Control and Life Support System (ECLSS). Current activities include ECLSS component design and development, computer model development, subsystem/integrated system testing, life testing, and general test support provided to the ISS program. Under ECLSS design, MSFC was responsible for the six major ECLSS functions, specifications and standard, component design and development, and was the architectural control agent for the ISS ECLSS. MSFC was responsible for ECLSS analytical model development. In-house subsystem and system level analysis and testing were conducted in support of the design process, including testing air revitalization, water reclamation and management hardware, and certain nonregenerative systems. The activities described herein were approved in task agreements between MSFC and NASA Headquarters Space Station Program Management Office and their prime contractor for the ISS, Boeing. These MSFC activities are in line to the designing, development, testing, and flight of ECLSS equipment planned by Boeing. MSFC's unique capabilities for performing integrated systems testing and analyses, and its ability to perform some tasks cheaper and faster to support ISS program needs, are the basis for the TTA activities.

Ray, C. D.↗

NASA NTRSDate not supplied

Gateway Integrated ECLSS Model Analysis of Intermodule Ventilation Failures

The Gateway Integrated ECLSS Model (GIEM) is a set of two independent models, made in Aspen Custom Modeler (ACM) and Thermal Desktop (TD), of the Gateway stack and each modules' associated environment control and life support system (ECLSS). The GIEM utilizes the 41-Node Metabolic Man (METMAN) to simulate crew inside the Gateway consuming O2 and producing CO2, H2O, and heat for the ECLSS to remove. The modules and visiting vehicles all have different levels of ECLSS capabilities and may rely on other modules and Intermodular Ventilation (IMV), which is used to exchange gas between the modules, to ensure the entire Gateway environment is controlled. If IMV were to fail or be turned off, some vehicles may have limited access to necessary ECLSS functions. This analysis focuses on evaluating O2, CO2, and H2O levels when crew are in vehicles without their own life support and IMV has failed to evaluate how long before the atmosphere is unsafe for the crew. This analysis uses the integrated nature of the GIEM to look at time to effect for O2 depletion and CO2 and H2O buildup when crew are working in vehicles that have been cut off from the ECLSS-active portion of the stack. This information is used to inform for how long crew can safely continue working in the ECLSS-inactive vehicles before experiencing a requirement violation or physical limitation and can be referenced when developing maintenance and emergency response concept of operations (ConOps).

Lawrence Barrett↗

NASA NTRS1991

Intelligent monitoring and diagnosis systems for the Space Station Freedom ECLSS

Specific activities in NASA's environmental control and life support system (ECLSS) advanced automation project that is designed to minimize the crew and ground manpower needed for operations are discussed. Various analyses and the development of intelligent software for the initial and evolutionary Space Station Freedom (SSF) ECLSS are described. The following are also discussed: (1) intelligent monitoring and diagnostics applications under development for the ECLSS domain; (2) integration into the MSFC ECLSS hardware testbed; and (3) an evolutionary path from the baseline ECLSS automation to the more advanced ECLSS automation processes.

Dewberry, Brandon S.↗

NASA NTRS2004

ISS ECLSS: 3 Years of Logistics for Maintenance

The International Space Station (ISS) Environmental Control and Life Support System (ECLSS) is designed to be maintainable. During the 3 years since the ISS US Lab became operational, there have been numerous ECLSS Orbital Replacement Units (ORUs) launched and returned to Maintain the ECLSS operation in the US segments. The maintenance logistics have provided tools for maintenance, replaced limited life ORUs and failed ORUs, upgraded ECLSS hardware to improve reliability and placed critical spares onboard prior to need. In most cases, the removed ORUs have been returned for either failure analysis and repair or refurbishment. This paper describes the ECLSS manifesting history and maintenance events and quantifies the numbers of ECLSS items, weights, and volumes.

Shkedi, Brienne↗

NASA NTRS2010

Regenerative (Regen) ECLSS Operations Water Balance

In November 2008, the Water Regenerative System racks were launched aboard Space Shuttle flight, STS-126 (ULF2) and installed and activated on the International Space Station (ISS). These racks, consisting of the Water Processor Assembly (WPA) and Urine Processor Assembly (UPA), completed the installation of the Regenerative (Regen) ECLSS systems which includes the Oxygen Generator Assembly (OGA) that was launched 2 years prior. With the onset of active water management on the US segment of the ISS, a new operational concept was required, that of "water balance." Even more recently, in 2010 the Sabatier system came online which converts H2 and CO2 into water and methane. The Regen ECLSS systems accept condensation from the atmosphere, urine from crew, and processes that fluid via various means into potable water which is used for crew drinking, building up skip-cycle water inventory, and water for electrolysis to produce oxygen. Specification rates of crew urine output, condensate output, O2 requirements, toilet flush water and drinking needs are well documented and used as a general plan when Regen ECLSS came online. Spec rates are useful in long term planning, however, daily or weekly rates are dependent on a number of variables. The constantly changing rates created a new challenge for the ECLSS flight controllers, who are responsible for operating the ECLSS systems onboard ISS. This paper will review the various inputs to rate changes and inputs to planning events, including but not limited to; crew personnel makeup, Regen ECLSS system operability, vehicle traffic, water containment availability, and Carbon Dioxide Removal Assembly (CDRA) capability. Along with the inputs that change the various rates, the paper will review the different systems, their constraints and finally the operational means by which flight controllers manage this new challenge of "water balance."

Tobias, Barry↗

NASA NTRS1973

Space Shuttle Orbiter ECLSS.

The Orbiter Environmental Control and Life Support System (ECLSS) provides the functions of atmosphere revitalization, crew life support, active thermal conditioning, and airlock support for EVA and docking activities. The ECLSS must satisfy the requirements of orbital missions with four to ten crewmembers and mission duration of a few hours to 30 days and the requirements associated with an atmospheric horizontal flight test program and ferry flight missions. The ECLSS development plan utilizes an ECLSS ground test article and thermal/vacuum testing to support the first horizontal flight test at the end of 1976. The ground testing and horizontal flight test program certify the Orbiter ECLSS for the first orbital flight in early 1978.

Stoll, O. T.↗

NASA NTRS1990

Space Station Freedom ECLSS: A step toward autonomous regenerative life support systems

The Environmental Control and Life Support System (ECLSS) is a Freedom Station distributed system with inherent applicability to extensive automation primarily due to its comparatively long control system latencies. These allow longer contemplation times in which to form a more intelligent control strategy and to prevent and diagnose faults. The regenerative nature of the Space Station Freedom ECLSS will contribute closed loop complexities never before encountered in life support systems. A study to determine ECLSS automation approaches has been completed. The ECLSS baseline software and system processes could be augmented with more advanced fault management and regenerative control systems for a more autonomous evolutionary system, as well as serving as a firm foundation for future regenerative life support systems. Emerging advanced software technology and tools can be successfully applied to fault management, but a fully automated life support system will require research and development of regenerative control systems and models. The baseline Environmental Control and Life Support System utilizes ground tests in development of batch chemical and microbial control processes. Long duration regenerative life support systems will require more active chemical and microbial feedback control systems which, in turn, will require advancements in regenerative life support models and tools. These models can be verified using ground and on orbit life support test and operational data, and used in the engineering analysis of proposed intelligent instrumentation feedback and flexible process control technologies for future autonomous regenerative life support systems, including the evolutionary Space Station Freedom ECLSS.

Dewberry, Brandon S.↗

NASA NTRS1990

The Environmental Control and Life Support System (ECLSS) advanced automation project

The objective of the environmental control and life support system (ECLSS) Advanced Automation Project is to influence the design of the initial and evolutionary Space Station Freedom Program (SSFP) ECLSS toward a man-made closed environment in which minimal flight and ground manpower is needed. Another objective includes capturing ECLSS design and development knowledge future missions. Our approach has been to (1) analyze the SSFP ECLSS, (2) envision as our goal a fully automated evolutionary environmental control system - an augmentation of the baseline, and (3) document the advanced software systems, hooks, and scars which will be necessary to achieve this goal. From this analysis, prototype software is being developed, and will be tested using air and water recovery simulations and hardware subsystems. In addition, the advanced software is being designed, developed, and tested using automation software management plan and lifecycle tools. Automated knowledge acquisition, engineering, verification and testing tools are being used to develop the software. In this way, we can capture ECLSS development knowledge for future use develop more robust and complex software, provide feedback to the knowledge based system tool community, and ensure proper visibility of our efforts.

Dewberry, Brandon S.↗

NASA NTRSDate not supplied

Regenerative ECLSS and Logistics Analysis for Sustained Lunar Surface Missions

As NASA develops concepts for sustained crew missions to the lunar surface, a crucial component of mission planning will be evaluating the required amount of logistics to support the crew, surface systems, and science operations. This amount could be substantial. Because NASA plans to conduct these missions on an annual basis, the complexity and cost of logistics delivery will likely drive campaign sustainability. Logistics quantity is partially a function of the regenerative Environmental Control and Life Support System (ECLSS) capability in habitable elements on the surface. The regenerative ECLSS recycles human waste to produce water and oxygen, reducing the consumables needed for a mission. Thus, an ECLSS with increased regenerative capability will require less logistics. However, an ECLSS with enhanced regenerative abilities will also increase the initial delivery mass of elements and require extra maintenance items and spares. This paper analyzes the tradeoff between initial delivery masses of different regenerative ECLSS options and the amount of logistics resupply required for each option.

Environmental Control and Life Support Systems↗

NASA NTRS1991

G189A modelling of Space Station Freedom's ECLSS

This paper contains a review of the requirements and design of the Environmental Control and Life Support System (ECLSS) for Space Station Freedom; a review of the G189A ECLSS computer program model developed at Boeing for the complete configuration of pressurized elements or volumes; and some significant computed results from this model showing transient performance for subsystems responsible for Temperature and Humidity Control,. Atmosphere Control and Supply, Air Revitalization, and Water Recovery and Management. The computed results presented here are important in assessing the capabilities of the ECLSS equipment in maintaining acceptable levels of temperature, humidity, 02, N2 and (2% in the occupied volumes during crew changeout events. These events involve up to four extra crew members from the Orbiter being located temporarily in the Space Station modules in addition to the normal contingent of four crew members. These additional crew members impose additional demands on the ECLSS equipment, in order to control the levels of the aforementioned quantities. Satisfactory control of all of these quantities was achieved. The maximum computed pp C02 was in the acceptable degraded performance regime. This level is higher than the 3.00 mm Hg upper limit for normal conditions

Environmental Control and Life Support Systems (EC↗

NASA NTRSDate not supplied

NextSTEP Appendix A Modular ECLSS Effort Lessons Learned

NASA’s Artemis program provides the first steps for earth-independent exploration starting with crewed habitats in cislunar space and progressing toward crewed landings on the lunar surface that will prepare systems and crews for the exploration of Mars. The Next Space Technology for Exploration Partnerships (NextSTEP) is a public-private partnership model that facilitates commercial development of deep space exploration capabilities in support of more extensive human spaceflight missions in and beyond cislunar space. NASA issued the original NextSTEP Broad Agency Announcement (BAA) to U.S. industry in late 2014 and issued the second BAA (NextSTEP-2) in April 2016. The first appendix under NextSTEP-2, Appendix A, focused on developing deep space habitation concepts, engineering design and development, and risk reduction efforts leading to a habitation capability in cislunar space. NASA solicited concepts to develop and refine the evolvable, modular architecture, functional allocation options, standards, and common interfaces required to enable interoperability of the aggregate system to provide long duration deep space transit habitation, specifically enhancements and testing of deep space Environmental Control and Life Support Systems (ECLSS). Collins Aerospace, formerly UTC Aerospace Systems (UTAS), was awarded a Phase 1 and subsequent Phase 2 contract to “develop concepts that group ECLS systems into logical modules maximizing the use of common components and the development of unique methods and design concepts that support in-flight maintenance and repair for future exploration systems.” This paper summarizes the work accomplished under this effort, the lessons that can be applied to development of forthcoming habitation elements, and the gaps remaining to achieve a more resilient, maintainable, repairable and adaptable system capable of installation on a wide variety of habitat platforms. A primary accomplishment of this effort is the development and maturation of a modular palletization concept to enable standard rack interfaces, post-launch outfitting, and decoupling of structural supports that withstand launch environments from those needed for lower on-orbit loads in order to reduce installed mass and repurposing of panels within the habitat. In the course of the effort, Collins assessed numerous architecture trades, including the use of condensing and noncondensing heat exchangers, the ability of modular units to accommodate various habitat volumes and thermal loading, and the most appropriate order of and timing of delivery of regenerative ECLSS hardware to orbital habitats. In addition to the modularity of hardware elements, Collins developed software approaches for distributed/modular command, control, and communication systems and innovative Bayesian fault detection and isolation techniques. Finally, the effort explored advanced maintainability and supportability concepts including the definition of maintenance units (MUs) in place of the traditional Orbital Replacement Units (ORUs), increasing parts commonality to reduce the number and type of spare parts, the use of augmented reality to guide crews during maintenance and repair procedures, and how crews would prepare for and recover from long durations of habitat dormancy. Now that the NextSTEP Modular ECLSS effort has come to a close, it’s important to identify the lessons learned and where they can be leveraged to improve NASA’s broader program of ECLSS technology development and demonstration and ultimately how they can increase the performance of future surface and orbital habitats.

NextSTEP↗

NASA NTRSDate not supplied

NextSTEP Appendix A Modular ECLSS Effort Lessons Learned

NASA’s Artemis program provides the first steps for earth-independent exploration starting with crewed habitats in cislunar space and progressing toward crewed landings on the lunar surface that will prepare systems and crews for the exploration of Mars. The Next Space Technology for Exploration Partnerships (NextSTEP) is a public-private partnership model that facilitates commercial development of deep space exploration capabilities in support of more extensive human spaceflight missions in and beyond cislunar space. NASA issued the original NextSTEP Broad Agency Announcement (BAA) to U.S. industry in late 2014 and issued the second BAA (NextSTEP-2) in April 2016. The first appendix under NextSTEP-2, Appendix A, focused on developing deep space habitation concepts, engineering design and development, and risk reduction efforts leading to a habitation capability in cislunar space. NASA solicited concepts to develop and refine the evolvable, modular architecture, functional allocation options, standards, and common interfaces required to enable interoperability of the aggregate system to provide long duration deep space transit habitation, specifically enhancements and testing of deep space Environmental Control and Life Support Systems (ECLSS). Collins Aerospace, formerly UTC Aerospace Systems (UTAS), was awarded a Phase 1 and subsequent Phase 2 contract to “develop concepts that group ECLS systems into logical modules maximizing the use of common components and the development of unique methods and design concepts that support in-flight maintenance and repair for future exploration systems.” This paper summarizes the work accomplished under this effort, the lessons that can be applied to development of forthcoming habitation elements, and the gaps remaining to achieve a more resilient, maintainable, repairable and adaptable system capable of installation on a wide variety of habitat platforms. A primary accomplishment of this effort is the development and maturation of a modular palletization concept to enable standard rack interfaces, post-launch outfitting, and decoupling of structural supports that withstand launch environments from those needed for lower on-orbit loads in order to reduce installed mass and repurposing of panels within the habitat. In the course of the effort, Collins assessed numerous architecture trades, including the use of condensing and noncondensing heat exchangers, the ability of modular units to accommodate various habitat volumes and thermal loading, and the most appropriate order of and timing of delivery of regenerative ECLSS hardware to orbital habitats. In addition to the modularity of hardware elements, Collins developed software approaches for distributed/modular command, control, and communication systems and innovative Bayesian fault detection and isolation techniques. Finally, the effort explored advanced maintainability and supportability concepts including the definition of maintenance units (MUs) in place of the traditional Orbital Replacement Units (ORUs), increasing parts commonality to reduce the number and type of spare parts, the use of augmented reality to guide crews during maintenance and repair procedures, and how crews would prepare for and recover from long durations of habitat dormancy. Now that the NextSTEP Modular ECLSS effort has come to a close, it’s important to identify the lessons learned and where they can be leveraged to improve NASA’s broader program of ECLSS technology development and demonstration and ultimately how they can increase the performance of future surface and orbital habitats.

NextSTEP↗

NASA NTRSDate not supplied

Mass Economy Evaluation for Integrated ECLSS and Propulsion Architecture

As missions in Low Earth Orbit (LEO) lengthen and extend to deep space, minimizing resupply needs becomes vital for sustaining crewed operations. Traditional life support systems depend on consumables resupplied from Earth, a method that is increasingly impractical for missions beyond LEO, such as lunar outposts or Mars transit. Long-duration missions require more efficient, autonomous systems that can recycle essential resources, particularly water and oxygen, to minimize the frequency and mass of resupply missions. The Environmental Control and Life Support System (ECLSS) is essential to such missions, with the International Space Station (ISS) serving as a testbed for advanced water recovery and partial oxygen recycling via physico-chemical methods. Yet, ECLSS and propulsion subsystems generally operate independently, despite overlapping requirements and potential areas for synergy. For instance, ECLSS byproducts, water, CO₂, and hydrogen, could be repurposed for propulsion, potentially reducing dedicated propellant mass and increasing overall system efficiency. One promising approach is to develop shared-resource architectures that integrate ECLSS with propulsion systems. This study examines the potential of such integration through the Sabatier CO₂ reduction process, focusing on water management as a key factor in system mass trade-offs. The Sabatier reaction produces water and methane from metabolic CO₂ and electrolytic hydrogen, partially closing the life support loop and providing methane, which could serve as a propellant. This integration could minimize waste, reduce resupply requirements, and enhance mission mass efficiency. A dynamic modeling framework will be used to simulate resource flows over long missions, capturing interactions between life support and propulsion. By comparing integrated versus separate system configurations, the study aims to quantify mass benefits and penalties, informing future habitat designs and trade studies for missions prioritizing autonomy and mass efficiency.

ECLSS↗