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This paper describes engineering rules of thumb for life support system design. One general design rule is that the longer the mission, the more the life support system should use regenerable technologies and recycling. A more specific rule is that, if plants supply more than about half the food, the plants will provide all the oxygen needed by the crew. There are many such design rules that can help in planning the analysis of life support systems or in assessing design concepts. These rules typically describe the results of steady state, “back of the envelope,” trade-off calculations. They are useful in suggesting plausible candidate life support system designs or approaches. Life support system engineers should consider the basic design rules and make quick steady state calculations as a guide before doing detailed design.

In efforts to generate a modeling and simulation system for the environmental control and life support system for a small plant growth chamber, the requirement for a biosynthetic water vapor source was found. The water vapor source was designed to inject a known and controlled rate of water vapor into the laboratory version of NASA Ames Research Center's Salad Machine. The rationale for a water vapor source, the design of the source device, the procedures and results of calibration and the method of integrating and utilizing the device with the Salad Machine are described.

The efficiency and robustness of pilot-automation interaction is a function of the volume of memorized action sequences required to use the automation to perform mission tasks. This paper describes a model of pilot cognition for the evaluation of the cognitive usability of cockpit automation. Five common cockpit automation design errors are discussed with examples.

Waste management is a vital function of spacecraft life support systems as it is necessary to meet crew health and safety and quality of life requirements. Depending on the specific mission requirements, waste management operations can include waste collection, segregation, containment, processing, storage and disposal. For the Crew Exploration Vehicle (CEV), addressing volume and mass constraints is paramount. Reducing the volume of trash prior to storage is a viable means to recover habitable volume, and is therefore a particularly desirable waste management function to implement in the CEV, and potentially in other spacecraft as well. Research is currently being performed at NASA Ames Research Center to develop waste compaction systems that can provide both volume and mass savings for the CEV and other missions.

The Spacelab Life Sciences-2 (SLS-2) mission provided scientists with the unique opportunity of obtaining inflight rodent tissue and blood samples during a 14-day mission flown in October, 1993. In order to successfully obtain these samples, Ames Research Center's Space Life Sciences Payloads Office has developed an innovative, modular approach to packaging the instruments used to obtain and preserve the inflight tissue and blood samples associated with the hematology experiments on SLS-2. The design approach organized the multitude of instruments into 12 different 5x6x1 inch kits which were each used to accomplish a particular experiment functional objective on any given day during the mission. The twelve basic kits included blood processing, isotope and erythropoietin injection, body mass measurement, and microscope slides.

A habitat for housing up to 32 Tenebrionid, black body beetles (Trigonoscelis gigas Reitter) has been developed at Ames Research Center for conducting studies to evaluate the effects of long duration spaceflight upon insect circadian timing systems. This habitat, identified as the Beetle Kit, provides an automatically controlled lighting system and activity and temperature recording devices, as well as individual beetle enclosures. Each of the 32 enclosures in a Beetle Kit allows for ad lib movement of the beetle as well as ventilation of the beetle enclosure via an externally operated hand pump. Two Beetle Kits were launched on STS-84 (Shuttle-Mir Mission-06) on May 15, 1997 and were transferred to the Priroda module of the Russian Mir space station on May 18 as part of the NASA/Mir Phase 1 Science Program. Following the Progress collision with Spektr on June 25, the Kits were transferred to the Kristall module. The beetles will remain on Mir for approximately 135 days.

NASA is currently developing two new human rated launch systems. They are the Crew Exploration Vehicle (CEV) and the Lunar Surface Access Module (LSAM). Both of these spacecraft will require new life support systems to support the crew. These life support systems can also be designed to reduce the mass required to keep humans alive in space. Water accounts for about 80% of the mass required to keep a person alive. As a result recycling water offers a high return on investment. Recycling water can also increase mission safety by providing an emergency supply of drinking water. This paper evaluates the potential benefits of two wastewater treatment technologies that have been designed to reduce the mass of the CEV and LSAM missions. For a 3 day CEV mission to the International Space Station (ISS) this approach could reduce the mass required to provide drinking water by 65% when compared to stored water. For an 18 day Lunar mission a mass savings of 70% is possible.

The space environment presents many challenges to the operation and functioning of life support systems. These challenges include reduced gravity, near vacuum ambient, extreme temperatures, and radiation. Proper testing and modeling of system components to account for these factors will be important for their verification. This paper describes the modeling and design of a reduced gravity test rig for waste management studies. The first investigation planned relate to the functioning of components of the Flexible Membrane Commode (FMC) currently under development at NASA Ames Research Center. The planned reduced gravity tests will be carried out in NASA's C'9 aircraft which provides approximately 25 seconds of reduced gravity per parabolic trajectory. The filling of the commode bag under the influence of a directed air flow will be studied. Simulated waste will be injected and cabin air will be used for directing the waste into the bag.

This paper presents a description of the Controlled Ecological Life Support System (CELSS) Antarctic Analog Project (CAAP) and its functionality as a pilot study for the design of a future Lunar-Mars habitat. A description of the prototype development testbed, located at Ames Research, is provided as well as an analysis of the key design parameters. The CAAP program is tasked with the development of a life support testbed at the South Pole. This facility will include food production, waste processing, and in situ energy production capabilities. The testbed will provide NASA with a remote facility located in an extremely harsh environment which has been designed to provide a useful analog to the deployment of a future Lunar-Martian habitat. NASA's program goals are the operational testing of life support technologies and the conduct of scientific studies to facilitate future technology selection and system design.

The Spacelab Life Sciences 2 (SLS-2) mission became NASA's longest duration Shuttle mission, lasting fourteen days, when Columbia landed on November 1, 1993. Located within the Spacelab were a total of 48 laboratory rats which were housed in two Research Animal Holding Facilities (RAHFs) developed by the Space Life Sciences Payloads Office (SLSPO) at Ames Research Center. In order to properly maintain the health and well-being of these important research animals, sufficient quantities of food and water had to be available for the duration of the mission. An Inflight Refill Unit was developed by the SLSPO to replenish the animals' drinking water inflight using the Shuttle potable water system in the middeck galley as the source of additional water. The Inflight Refill Unit consists of two major subsystems, a Fluid Pumping Unit (FPU) and a Collapsible Water Reservoir (CWR).

An innovative design that meets both Shuttle and Space Station requirements for a user-friendly, volume-efficient, portable glovebox system has been developed at Ames Research Center (ARC). The Standard Interface Glovebox (SIGB) has been designed as a two Middeck locker-sized system that mounts in a Middeck Rack Structure (MRS) or in any rack using the Standard Interface Rack (SIR) rail spacing. The MRS provides structural support for the SIGB during all aspects of the mission and is an interface consistent with NASA's desire for commonality of mechanical interfaces, allowing the SIGB to be flown on essentially any manned space platform. The SIGB provides an enclosed work volume which operates at negative pressure relative to ambient, as well as excellent lighting and ample work volume for anticipated life sciences-related experiment operations inflight.

A multi-discipline, multi-year collaborative spaceflight research program (NASA/Mir Science Program) has been established between the United States and Russia utilizing the capabilities of the Russian Mir Space Station and the NASA space shuttle fleet. As a key research discipline to be carried out onboard Mir, fundamental biology research encompasses three basic objectives: first, to investigate long-term effects of microgravity upon plant and avian physiology and developmental biology; second, to investigate the long-term effects of microgravity upon circadian rhythm patterns of biological systems; and third, to characterize the long-term radiation environment (internal and external) of the Russian Mir space station. The first joint U.S./Russian fundamental biology research on-board Mir is scheduled to begin in March, 1995 with the Mir mission 18 and conclude with the docking of the U.S. shuttle to Mir in June, 1995 during the STS-71, Spacelab/Mir Mission-1 (SLM-1).

This study investigated pilots' taxi performance, situation awareness and workload while taxiing with three different head-up display (HUD) symbology formats: Command-guidance, Situation-guidance and Hybrid. Command-guidance symbology provided the pilot with required control inputs to maintain centerline position; Situation-guidance symbology provided conformal, scene-linked navigation information; while the Hybrid symbology combined elements of both symbologies. Taxi speed, centerline tracking accuracy, workload and situation awareness were assessed. Taxi speed, centerline accuracy, and situation awareness were highest and workload lowest with Situation-guidance and Hybrid symbologies. These results are thought to be due to cognitive tunneling induced by the Command-guidance symbology. The conformal route information of the Situation-guidance and Hybrid HUD formats provided a common reference with the environment, which may have supported better distribution of attention.

One of the key questions addressed in the field of Astrobiology is based upon the assumption that life exists, or at one time existed, in locations throughout the universe. However, this assumption is just that, an assumption. No definitive proof exists. On Earth, life has been found to exist in many diverse environments. We believe that this tendency towards diversity supports the assumption that life could exist wherever environmental conditions are right to support it. There are several locations within our Solar System which might support environments which are conducive to life. However, to conclusively establish the existence of life in such locations we must be capable of sensing generic life forms. This paper provides a summary of several innovative techniques based on the use of fluorescent analysis for the direct detection of extraterrestrial life forms.

The development and characterization of an innovative approach for the control and elimination of gaseous toxins using single walled carbon nanotubes (SWNTs) promise superior performance over conventional approaches. This is due to the ability of the nanotubes to direct the selective uptake of gaseous species based on their controllable pore size, high adsorptive capacity and their effectiveness as catalyst supports for gaseous conversion. A metal impregnated SWNT material has been proposed and synthesized for removing and converting the toxins in the life support system.

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.

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.

This paper presents a novel health monitoring and fault adaptive control architecture for an unmanned hexrotor helicopter. The technologies developed to achieve the described level of robust fault contingency management include; 1.) A Particle Swarm Optimization (PSO) routine for maximizing the “built-in” fault tolerance that the closed loop flight control system affords, 2.) A two-stage Kalman filter scheme for real-time identification of faults that are masked by control system compensation, and 3.) A reconfigurable control allocation method which compensates for large degradations of the six main motor/rotor assemblies. The fault adaptive control system presented herein has strong robustness against small faults without the need for controller reconfiguration, and strong tolerance of large faults through adaptive accommodation of the fault source and severity.

Astrobiology is one of the most highly integrative scientific efforts ever undertaken, relying on the synthesis of sciences from astronomy to zoology and geology to genomics to discover the thread of life in the universe. These sciences must be further integrated with the technological revolutions in biotechnology, microminiaturization and information technology to realize the vast potential offered by NASA's mission suites. This paper discusses development of the Astrobiology Roadmap and novel management approaches which attempt to bring in the best scientific and technical talent available to bear on Astrobiology's goals, while simultaneously minimizing the overhead and time to flight for Astrobiology payloads.

The elemental composition of food consumed by astronauts is well defined. The major elements carbon, hydrogen, oxygen, nitrogen and sulfur are taken up in large amounts and these are often associated with the organic fraction (carbohydrates, proteins, fats etc) of human tissue. On the other hand, a number of the elements are located in the extracellular fluids and can be accounted for in the liquid and solid waste fraction of humans. These elements fall into three major categories - cationic macroelements (e.g. Ca, K, Na, Mg and Si), anionic macroelements (e.g. P, S and Cl and17 essential microelements, (e.g. Fe, Mn, Cr, Co, Cu, Zn, Se and Sr). When provided in the recommended concentrations to an adult healthy human, these elements should not normally accumulate in humans and will eventually be excreted in the different human wastes.