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Pyrolysis is a technology that can be used on future space missions to convert wastes to an inert char, water, and gases. The gases can be easily vented overboard on near term missions. For far term missions the gases could be directed to a combustor or recycled. The conversion to char and gases as well as the absence of a need for resupply materials are advantages of pyrolysis. A major disadvantage of pyrolysis is that it can produce tars that are difficult to handle and can cause plugging of the processing hardware. By controlling the heating rate of primary pyrolysis, the secondary (cracking) bed temperature, and residence time, it is possible that tar formation can be minimized for most biomass materials. This paper describes an experimental evaluation of two versions of pyrolysis reactors that were delivered to the NASA Ames Research Center (ARC) as the end products of a Phase II and a Phase III Small Business Innovation Research (SBIR) project.

Pyrolysis is a very versatile waste processing technology which can be tailored to produce a variety of solid, liquid, and/or gaseous products. The main disadvantages of pyrolysis processing are: (1) the product stream is more complex than for many of the alternative treatments; (2) the product gases cannot be vented directly into the cabin without further treatment because of the high CO concentrations. One possible solution is to combine a pyrolysis step with catalytic oxidation (combustion) of the effluent gases. This integration takes advantage of the best features of each process. The advantages of pyrolysis are: insensitivity to feedstock composition, no oxygen consumption, and batch operation. The main advantage of oxidation is the simplicity and consistency of the product stream. In addition, this hybrid process has the potential to result in a significant reduction in Equivalent System Mass (estimated at 10-40%) and system complexity.

This paper describes work that has begun at Ames Research Center on development of a heat melt compactor that can be used on near term and future missions. The heat melt compactor can handle wastes with a significant plastic composition and minimize crew interaction. The current solid waste management system employed on the International Space Station (ISS) consists of compaction, storage, and disposal. Wastes such as plastic food packaging and trash are compacted manually and wrapped in duct taped “footballs” by the astronauts. Much of the waste is simply loaded into the empty Russian Progress spacecraft that is used to bring supplies to ISS. The progress spacecraft and its contents are intentionally burned up in the earth's atmosphere during reentry. This manual method of trash management on ISS is a wasteful use of crew time and does not transition well to far term missions.

The current CO2 removal technology of NASA is very energy intensive and contains many non-optimized subsystems. This paper discusses the concept of a next-generation, membrane-integrated, adsorption processor for CO2 removal and compression in closed-loop air revitalization systems. The membrane module removes water from the feed, passing it directly into the processor's exhaust stream; it replaces the desiccant beds in the current four-bed molecular sieve system, which must be thermally regenerated. Moreover, in the new processor, CO2 is removed and compressed in a single two-stage unit. This processor will use much less power than NASA's current CO2 removal technology and will be capable of maintaining a lower CO2 concentration in the cabin than that can be achieved by the existing CO2 removal systems.

Remote Tower Sensor Systems are proof-of-concept prototypes being developed by NASA/Ames Research Center (NASA/ARC) with collaboration with the FAA and NOAA. RTSS began with the deployment of an Airport Approach Zone Camera System that includes real-time weather observations at San Francisco International Airport. The goal of this research is to develop, deploy, and demonstrate remotely operated cameras and sensors at several major airport hubs and un-towered airports. RTSS can provide real-time weather observations of airport approach zone. RTSS will integrate and test airport sensor packages that will allow remote access to real-time airport conditions and aircraft status.

To fully conduct research that will support the far-term concepts, technologies and methods required to improve the safety of Air Transportation a simulation environment of the requisite degree of fidelity must first be in place. The Virtual National Airspace Simulation (VNAS) will provide the underlying infrastructure necessary for such a simulation system. Aerospace-specific knowledge management services such as intelligent data-integration middleware will support the management of information associated with this complex and critically important operational environment. This simulation environment, in conjunction with a distributed network of super-computers, and high-speed network connections to aircraft, and to Federal Aviation Administration (FAA), airline and other data-sources will provide the capability to continuously monitor and measure operational performance against expected performance.

Of the many competing technologies for resource recovery from solid wastes for long duration manned missions such as a lunar or Mars base, incineration technology is one of the most promising and certainly the most well developed in a terrestrial sense. Various factors are involved in the design of an optimum fluidized bed incinerator for inedible biomass. The factors include variability of moisture in the biomass, the ash content, and the amount of fuel nitrogen in the biomass. The crop mixture in the waste will vary; consequently the nature of the waste, the nitrogen content, and the biomass heating values will vary as well. Variation in feed will result in variation in the amount of contaminants such as nitrogen oxides that are produced in the combustion part of the incinerator. The incinerator must be robust enough to handle this variability. Research at NASA Ames Research Center using the fluidized bed incinerator has yielded valuable data on system parameters and variables.

Determining the fundamental role of gravity in vital biological systems in space is one of six science and research areas that provides the philosophical underpinning for why NASA exists. The study of cells, tissues, and microorganisms in a spaceflight environment holds the promise of answering multiple intriguing questions about how gravity affects living systems. To enable these studies, specimens must be maintained in an environment similar to that used in a laboratory. Cell culture studies under normal laboratory conditions involve maintaining a highly specialized environment with the necessary temperature, humidity control, nutrient, and gas exchange conditions. These same cell life support conditions must be provided by the International Space Station (ISS) Cell Culture Unit (CCU) in the unique environment of space. The CCU is a perfusion-based system that must function in microgravity, at unit gravity (1g) on earth, and from 0.1g up to 2g aboard the ISS centrifuge rotor.

The animal habitat under development for the International Space Station (ISS) provides a unique opportunity for the physiological and biological science community to perform controlled experiments in microgravity on rats and mice. This paper discusses the complexities that arise in developing a new animal habitat to be flown aboard the ISS. Such development is incremental and moves forward by employing the past successes, learning from experienced shortcomings, and utilizing the latest technologies. The standard vivarium cage on the ground can be a very simple construction, however the habitat required for rodents in microgravity on the ISS is extremely complex. This discussion presents an overview of the system requirements and focuses on the unique scientific and engineering considerations in the development of the controlled animal habitat parameters. In addition, the challenges to development, specific science, animal welfare, and engineering issues are covered.

Crop production in space habitats is currently under consideration as part of an advanced life support system. The scenarios for crop production vary depending on the mission objectives. For a mission scenario such as the International Space Station (ISS), current efforts propose only salad crop production. However in order to grow salad crops, there is a need for plant nutrients (elements) such as N, P, K, Ca, etc., which constitutes about 10% of dry weight of the plant. Nitrogen and potassium are the major elements needed by salad crops and currently require resupply on Station. However, it is feasible that these macronutrients could be recovered through the waste materials generated by the crew. The proposed concepts are non-oxidative and simple in design. This paper considers the potential for reclaiming macronutrients from urine and gray water concentrates from water recovery systems.

Flight activities during the Cargo Airline Association's Ohio Valley Operations Evaluation (OpEval) were focused on near-term Cockpit Display of Traffic Information (CDTI) applications. Seven CDTI applications were ranked from highest to lowest priority, and the first two, Enhanced Visual Acquisition for “See & Avoid”, and Enhanced Visual Approaches, were evaluated during OpEval. Five other applications were demonstrated. For the Enhanced Visual Acquisition and Enhanced Visual Approach applications, a detailed, comprehensive operational concept document was prepared. The operational concept and the associated CDTI requirements were tested during OpEval. Both pilots and controllers reported that the CDTI augmented the visual acquisition and visual approach tasks and improved pilot awareness of surrounding traffic.

The concept of free flight introduces many challenges for both air and ground aviation operations. Of considerable concern has been the issue of moving from centralized control and responsibility to decentralized control and distributed responsibility for aircraft separation. Data from capacity studies suggest that we will reach our capacity limits with ATC centralized control within the next 2 decades, if not sooner. Based on these predictions, research on distributed air-ground concepts was under taken by NASA Advanced Air Transportation Technologies Program to identify and develop air-ground concepts in support of free-flight operations. This paper will present the results of a full mission air-ground simulation conducted in the NASA Crew Vehicle Systems Research Facility. The purpose of the study was to evaluate the effect of advanced displays with “intent” (4-D flight plans) information on flight crew and ATC performance during limited free-flight operations.

NASA is developing a Telescience Support Center (TSC) at the Ames Research Center. The center will be part of the infrastructure needed to conduct research in the Space Station and has been tailored to satisfy the requirements of the fundamental biology research program. The TSC will be developed from existing facilities at the Ames Research Center. Ground facility requirements have been derived from the TSC functional requirements. Most of the facility requirements will be satisfied with minor upgrades and modifications to existing buildings and laboratories. The major new development will be a modern data processing system. The TSC is being developed in three phases which correspond to deliveries of Biological Research Facility equipment to Station. The first phase will provide support for early hardware in flight Utilization Flight −1 (UF-1) in 2001.

The development of virtual environment technology at NASA Ames Research Center and other research institutions has created opportunities for enhancing human performance. The application of this technology to training astronaut flight crews planning to go onboard the International Space Station has already begun at the NASA Johnson Space Center. A unique application of virtual environments to crew training is envisioned at NASA Ames Research Center which combines state of the art technology with haptic feedback to create a method for training crewmembers on critical life sciences operations which require fine motor skills. This paper describes such a concept, known as the Virtual Glovebox, as well as surveys other applications of virtual environments to astronaut crew training.

The Autonomous Garden Pod (AG-Pod) is a modular crop production system that can lower the equivalent system mass (ESM) for bioregenerative life support systems. AG-Pod combines existing technologies, many of which are at the technology readiness level (“TRL”) 8 or 9, into a flight-ready system adaptable to many needs from Space Station microgravity plant research to interplanetary transit and planetary surface food production systems. The plant-rated module resides external to the spacecraft pressurized volume and can use natural direct solar illumination. This reduces the ESM of crop production systems by eliminating the use of spacecraft internal pressurized volume and by reducing power and heat rejection resources that would be needed for full artificial lighting. However, lowering of the crop production ESM is also achieved from the use of lightweight structures including composite and inflatable technology.

Aeroponics is the process of growing plants in an air/mist environment without the use of soil or an aggregate media. Aeroponics has contributed to advances in several areas of study including root morphology, nutrient uptake, drought and flood stress, and responses to variations in oxygen and/or carbon dioxide root zone concentrations. The adaptability of the aeroponic process that has benefited researchers makes its application to spaceflight plant growth systems appealing. Greater control of growth parameters permits a greater range of crop performance throttling and the elimination of aggregates or common growth substrates lowers system mass, lessens disease propagation between plants, and can decrease the required crew time for both planting and harvesting.

The Centrifuge Accommodation Module (CAM) will be the home of the fundamental biology research facilities on the International Space Station (ISS). These facilities are being built by the Biological Research Project (BRP), whose goal is to oversee development of a wide variety of habitats and host systems to support life sciences research on the ISS. The habitats and host systems are designed to provide life support for a variety of specimens including cells, bacteria, yeast, plants, fish, rodents, eggs (e.g., quail), and insects. Each habitat contains specimen chambers that allow for easy manipulation of specimens and alteration of sample numbers. All habitats are capable of sustaining life support for 90 days and have automated as well as full telescience capabilities for sending habitat parameters data to investigator homesite laboratories.

One of the major impediments to human Mars missions is the development of appropriate countermeasures for long term physiological response to the micro-gravity environment. A plethora of countermeasure approaches have been advanced from strictly pharmacological measures to large diameter rotating spacecraft that would simulate a 1-g environment (the latter being the most conservative from a human health perspective). The different approaches have significantly different implications not only on the overall system design of a Mars Mission Vehicle (MMV) but on the necessary earth-orbiting platform that would be required to qualify the particular countermeasure system. It is found that these different design options can be conveniently categorized in terms of the order of magnitude of the rotation diameter required (100's, 10's, 1's, 0 meters). From this, the different mass penalties associated with each category can be generally compared.

This paper describes research and development for reducing the aerodynamic drag of heavy vehicles by demonstrating new approaches for the numerical simulation and analysis of aerodynamic flow. Experimental validation of new computational fluid dynamics methods are also an important part of this approach. Experiments on a model of an integrated tractor-trailer are underway at NASA Ames Research Center and the University of Southern California (USC). Companion computer simulations are being performed by Sandia National Laboratories (SNL), Lawrence Livermore National Laboratory (LLNL), and California Institute of Technology (Caltech) using state-of-the-art techniques.

A processing system has been developed to meet increasing demands for detailed noise measurement of aircraft in wind tunnels. Phased arrays enable spatial and amplitude measurements of acoustic sources, including low signal-to-noise sources not measurable by conventional measurement techniques. The Microphone Array Phased Processing System (MAPPS) provides processing and visualization of acoustic array measurements made in wind tunnels. The system uses networked parallel computers to provide noise maps at selected frequencies in a near real-time testing environment. The system has been successfully used in two subsonic, hard-walled wind tunnels, the NASA Ames 7- by 10-Foot Wind Tunnel and the NASA Ames 12-Foot Wind Tunnel. Low level airframe noise that can not be measured with traditional techniques was measured in both tests.