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The general operation of KATE, an artificial intelligence controller, is outlined. A shuttle environmental control system (ECS) demonstration system for KATE is explained. The knowledge base model for this system is derived. An experimental test procedure is given to verify parameters in the model.
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.
One concept for future space flights is to construct building blocks for a wide variety of avionics systems. Once a unit has served its original purpose, it can be removed from the original vehicle and reused in a similar or dissimilar function, depending on the function blocks the unit contains. For example: Once a lunar lander has reached the moon's surface, an engine controller for the Lunar Decent Module would be removed and used for a lunar rover motor control unit or for a Environmental Control Unit for a Lunar Habitat. This senior design project included the investigation of a wide range of functions of space vehicles and possible uses. Specifically, this includes: (1) Determining and specifying the basic functioning blocks of space vehicles. (2) Building and demonstrating a concept model. (3) Showing high reliability is maintained. The specific implementation of this senior design project included a large project team made up of Systems, Electrical, Computer, and Mechanical Engineers/Technologists. The efforts were made up of several sub-groups that each worked on a part of the entire project. The large size and complexity made this project one of the more difficult to manage and advise. Typical projects only have 3-4 students, but this project had 10 students from five different disciplines. This paper describes the difference of this large project compared to typical projects, and the challenges encountered. It also describes how the systems engineering approach was successfully implemented so that the students were able to meet nearly all of the project requirements.
As the International Space Station (ISS) travels 17,500 miles per hour, normal is having a constant sensation of free-falling. Normal is no rain, but an extreme amount of shine.with temperatures reaching 250 F when facing the Sun. Thanks to a number of advanced control systems onboard the ISS, however, the interior of the station remains a cool, comfortable, normal environment where astronauts can live and work for extended periods of time. There are two main control systems on the ISS that make it possible for humans to survive in space: the Thermal Control System (TCS) and the Environmental Control and Life Support system. These intricate assemblies work together to supply water and oxygen, regulate temperature and pressure, maintain air quality, and manage waste. Through artificial means, these systems create a habitable environment for the space station s crew. The TCS constantly works to regulate the temperature not only for astronauts, but for the critical instruments and machines inside the spacecraft as well. To do its job, the TCS encompasses several components and systems both inside and outside of the ISS. Inside the spacecraft, a liquid heat-exchange process mechanically pumps fluids in closed-loop circuits to collect, transport, and reject heat. Outside the ISS, an external system circulates anhydrous ammonia to transport heat and cool equipment, and radiators release the heat into space. Over the years, NASA has worked with a variety of partners.public and private, national and international. to develop and refine the most complex thermal control systems ever built for spacecraft, including the one on the ISS.
At its core, the field of microbial experimental evolution seeks to elucidate the natural laws governing the history of microbial life by understanding its underlying driving mechanisms. However, observing evolution in nature is complex, as environmental conditions are difficult to control. Laboratory-based experiments for observing population evolution provide more control, but manually culturing and studying multiple generations of microorganisms can be time consuming, labor intensive, and prone to inconsistency. We have constructed a prototype, closed system device that automates the process of directed evolution experiments in microorganisms. It is compatible with any liquid microbial culture, including polycultures and field samples, provides flow control and adjustable agitation, continuously monitors optical density (OD), and can dynamically control environmental pressures such as ultraviolet-C (UV-C) radiation and temperature. Here, the results of the prototype are compared to iterative exposure and survival assays conducted using a traditional hood, UV-C lamp, and shutter system.
The International Space Station (ISS) Environmental Control and Life Support System includes equipment speci.cally designed to actively remove trace chemical contamination from the cabin atmosphere. In the U.S. on-orbit segment, this function is provided by the trace contaminant control subassembly (TCCS) located in the atmosphere revitalization subsystem rack housed in the laboratory module, Destiny. The TCCS employs expendable adsorbent beds to accomplish its function leading to a potentially signi.cant life cycle cost over the life of the ISS. Because maintaining the TCCSs proper can be logistically intensive, its performance in .ight has been studied in detail to determine where savings may be achieved. Details of these studies and recommendations for improving the TCCS s process economics without compromising its performance or crew health and safety are presented and discussed.
Environmental control of nature using natural energy sources - solar and earth radiation, and lunar and solar gravitational effects
Saturn I /SA-8/ launch vehicle - environmental control systems, functional description, index of finding numbers, and schematics of launch complex
Physiological factor, hardware, and environmental control tradeoffs for one and two gas systems of space cabin atmospheres
Environmental control and life support systems analyses for improved Manned Orbital Research Laboratory
Review of u.s. and u.s.s.r. bioastronautic activities, discussing environmental control and life support systems of coopers flight and the soviet cosmonauts flight, and consideration psychophysiological phenomena
Vibration/acoustics digitally controlled environmental testing, describing configuration and operation of control system and statistical requirements for noise generation
A habitable atmosphere is a fundamental requirement for human spaceflight. To meet such a requirement, the cabin atmosphere must be constantly scrubbed to maintain human life and system functionality. The primary system for atmospheric scrubbing of the US on-orbit segment (USOS) of the International Space Station (ISS) is the Trace Contaminant Control System (TCCS). As part of the Environmental Control and Life Support Systems (ECLSS) atmosphere revitalization rack in the US Lab, the TCCS operates continuously, scrubbing trace contaminants generated primarily by two sources: the metabolic offgassing of crew members and the offgassing of equipment in the ISS. It has been online for approximately 95% since activated in February 2001. The TCCS is comprised of a charcoal bed, a catalytic oxidizer, and a lithium hydroxide post-sorbent bed, all of which are designed to be replaced onorbit when necessary. In 2006, all three beds were replaced following an observed increase in the system resistance that occurred over a period several months. The beds were returned to ground and subjected to a test, teardown and evaluation to investigate the root cause(s) of the decrease in flow rate through the system. In addition, various chemical and physical analyses of the bed materials were performed to determine contaminant loading and any changes in performance. This paper will mainly focus on the results of these analyses and how this correlates with what has been observed from archival sampling and onorbit events. This may provide insight into the future performance of the TCCS and rate of change for orbital replacement units in the TCCS.
In-Space Manufacturing (ISM) centers around NASA’s growing need and ability to produce space technologies on demand in space. As the future of long term presence in space and deep space exploration approach, fundamental questions of our dependence on earth resupply to Low Earth Orbit (LEO) remain unanswered. ISM is leading various effort to evaluate the feasibility of producing essential spares and redundant parts on demand to enable a sustainable space-based supply chain model for part resupply. Among the parts and systems being considered, Avionics form the neural network of modern day aircraft and space vehicles providing a wealth of information ranging from Guidance, Navigation, and Control (GN&C) systems to on board Environmental Control and Life Support (ECLS) systems. Recent advances in the use of Aerosol Jet Technology to print Avionics components ranging from electrical traces on a circuit board to complex transistors and sensors raise the possibility of using such technology to reproduce or recreate electronic parts on demand with the help of custom electronics 3D printers. The challenge herein lies within the ability of such printers to generate and deposit an aerosol of electronic material utilizing processes independent of or enhanced by gravity to ensure controllably identical or improved behavior of the aerosol in an International Space Station (ISS) laboratory and on the ground. The behavior as well as the hazards and properties associated with such aerosols in a microgravity environment must be understood well in order to merit a feasible approach to utilizing them for manufacturing in space. In this report, we outline the experimental setup of a modified conventional vaping device to be used as the ideal gravity independent thermal atomization mechanism to generate aerosol. Our objective is to identify the ideal mass, density, and volume of our aerosolized droplets of ink to conclude that there exist a threshold of aerosolized ink droplet sizes that are indeed independent of the effects of gravity and remain stable after atomization. We use a Malvern Spraytec® Spray Particle Size Analyzer to perform real-time laser diffraction measurement of our ink droplets during atomization. The droplet size between conductive ink, dielectric ink and vegetable glycerin have been measured and contrasted. Furthermore, the mechanism of thermal atomization versus traditional pneumatic and ultrasonic atomization for operation in microgravity have been explored.
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
Objective: Leverage additive manufacturing to fortify Environmental Control and Life Support Systems (ECLSS) manifolds and other vulnerable components against biofilm growth during dormancy by eliminating dead legs to reduce total stagnate fluid volume and available nutrients and by printing from inherently biocidal materials.
A key technology development driver in environmental control systems and next generation optics are discussed utilizing thin film development borrowed from the semiconductor industry. The optical and physical properties of spacecraft radiator coatings are dictated by orbital environmental conditions. For example, coatings must adequately dissipate charge buildup when orbital conditions, such as polar, geostationary or gravity neutral, result in surface charging. Current dissipation techniques include depositing a layer of ITO (indium tin oxide) on the radiator surface in a high temperature process. The application of these enhanced coatings must be such that the properties in question are tailored to mission-specific requirements. The multi-billion-dollar semiconductor industry has adopted Atomic Layer Deposition (ALD) for self-assembly and atomic-scale placement. ALD is a cost-effective nanoadditive-manufacturing technique that allows for the conformal coating of substrates with atomic control in a benign temperature and pressure environment. By using ALD, modification of these coatings can be accomplished during coating application preprocessing. The preprocessing is rendered directly on the coating dry pigment before binding. Through the introduction of paired precursor gases, thin films can be deposited on a myriad of substrates ranging from glass, polymers, aerogels, metals, powders, and other high aspect-ratio micro- and nano- structures. By providing atomic-level control, where single layers of atoms can be deposited, the fabrication of metal transparent films, precise nano-laminates, and coatings of nano-channels and pores is achievable. A method has been demonstrated for the ALD of In2O3 and films on a variety of substrates from Si(100) wafers, glass slides, and on Z93P pigments resulting in a direct spaceflight application. Results will be presented that verify the chemical composition of ALD pigments and charge dissipation properties when the pigment goes through its binding and coating process and we present early results of ALD for carbon nanotube formation and encapsulation.
Human missions in space, from short-duration shuttle missions lasting no more than several days to the medium-to-long-duration missions planned for the International Space Station, face a number of hazards that must be understood and mitigated for the mission to be carried out safely. Among these hazards are those posed by the internal environment of the spacecraft itself; through outgassing of toxic vapors from plastics and other items, failures or off-nominal operations of spacecraft environmental control systems, accidental exposure to hazardous compounds used in experiments: all present potential hazards that while small, may accumulate and pose a danger to crew health. The first step toward mitigating the dangers of these hazards is understanding the internal environment of the spacecraft and the compounds contained within it. Future spacecraft will have integrated networks of redundant sensors which will not only inform the crew of hazards, but will pinpoint the problem location and, through analysis by intelligent systems, recommend and even implement a course of action to stop the problem. This strategic plan details strategies to determine NASA's requirements for environmental monitoring and control systems for future spacecraft, and goals and objectives for a program to answer these needs.