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A modular and scalable Dense Medium Plasma Water Purification Reactor was developed, which uses atmospheric-pressure electrical discharges under water to generate highly reactive species to break down organic contaminants and microorganisms. Key benefits of this novel technology include: (i) extremely high efficiency in both decontamination and disinfection; (ii) operating continuously at ambient temperature and pressure; (iii) reducing demands on the containment vessel; and (iv) requiring no consumables. This plasma based technology was developed to replace the catalytic reactor being used in the planned International Space Station Water Processor Assembly.

Students, as members of Team Paradigm, at the University of Wisconsin-Madison have designed a charge regulating, parallel hybrid electric Dodge Intrepid for the 1997 FutureCar Challenge (FCC97). The goals for the Wisconsin “FutureCow” are to achieve an equivalent fuel consumption of 26 km/L (62 mpg) and Tier 2 Federal Emissions levels while maintaining the full passenger/cargo room, appearance, and feel of a stock Intrepid. These goals are realized through drivetrain simulations, a refined vehicle control strategy, decreased engine emissions, and aggressive weight reduction. The vehicle development has been coupled with 8,000 km of reliability and performance testing to ensure Wisconsin will be a strong competitor at the FCC97.

The demand for highly flexible manipulation of plant growth generations, modification of specific plant processes, and genetically engineered crop varieties in a controlled environment has led to the development of a Commercial Plant Biotechnology Facility (CPBF). The CPBF is a quad-middeck locker playload to be mounted in the EXPRESS Rack that will be installed in the International Space Station (ISS). The CPBF integrates proven ASTROCULTURE” technologies, state-of-the-art control software, and fault tolerance and recovery technologies together to increase overall system efficiency, reliability, robustness, flexibility, and user friendliness. The CPBF provides a large plant growing volume for the support of commercial plant biotechnology studies and/or applications for long time plant research in a reduced gravity environment.

Automation of space-based scientific operations minimizes the crew time needs for experiments while increasing the efficiency and quality of science operations. ORBITEC has completed the development of a space qualifiable prototype of a Shared Multi-Use Remote Robotics Facility (SMURRF). SMURRF, sized for a Middeck Locker (MDL) application, provides a simple, flexible, and functional manipulator to assist space operations, in manned or unmanned modes, carried out in lockers or racks onboard the Space Shuttle and the International Space Station (ISS). It will be primarily operated in an automated mode with additional remote command/control capability from the ground or from space. Ground trials have demonstrated that many operations can be autonomously performed without the presence of a human operator.

A Plasma Air Decontamination System (PADS) is being developed by ORBITEC for trace contaminant control in spacecraft cabin air, based on non-thermal, atmospheric pressure plasma discharges that generate various highly reactive species that can react with and break down trace air contaminants. It uses a simple and modular design, and may be scaled up or down to meet the requirements of different applications. The prototype PADS reactor has successfully demonstrated removal of ammonia and other selected volatile organic carbons from air, including acetone, ethylbenzene, methane, and methylene chloride. It has the potential to replace the existing high-temperature catalytic oxidizers.

Orbital Technologies Corporation (ORBITEC) utilizes a variety of in-house testing capabilities (vibration, shock, acoustic loads, space vacuum, temperature cycling, humidity, burn-in, etc.) for qualification and screening of flight components. A lunar dust chamber was designed and constructed to include exposure to lunar regolith and dust simulants. A full factorial design of experiment (DOE) was used to investigate the failure modes of electric fans when exposed to airborne JSC-1AF lunar regolith simulant. This type of testing provides valuable insight into reliability predictions, planned maintenance of a system, and component design improvements to mitigate the effects of lunar dust. Incorporating lunar dust exposure testing at an early stage in the design process will help ensure proper system performance and reliability.

Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV)/coir fiber composites were prepared via both conventional and microcellular injection-molding processes. The surface of the hydrophilic coir fiber was modified by alkali and silane-treatment to improve its adhesion with PHBV. The morphology, thermal, and mechanical properties were investigated. The addition of coir fiber (treated and untreated) reduced cell size and increased cell density. Further decrease in cell size and increase in cell density were observed for treated fibers compared with PHBV/untreated fiber composites. Mechanical properties such as specific toughness and strain-at-break improved for both solid and microcellular specimens with the addition of coir fibers (both treated and untreated); however, the specific modulus remained essentially the same statistically while the specific strength decreased slightly.

Based upon the development experience and flight heritage of the Biomass Production System, the Plant Research Unit embodies the next generation in the evolution of on-orbit plant research systems. The design focuses on providing the finest scientific instrument possible, as well as providing a sound platform to support future capabilities and enhancements. Performance advancements, modularity and robustness characterize the design. This new system will provide a field ready, highly reliable research tool.

As space hardware continues to grow in complexity, the demands on crews expected to be able to operate and maintain this equipment continue to grow. In terms of the International Space Station, the demands on the crew have been further increased by the reduction in crew capacity from the originally planned seven members down to three. This situation has prompted the need to find new ways of training that can meet these demands. In particular, just-in-time training techniques promise to enable crew members to correctly execute procedures that they have never performed before on equipment that they are only marginally familiar with or perhaps have never even seen before. To enable crews to work with unfamiliar procedures or equipment, we believe that it is necessary to employ a highly visual approach to convey the complex spatial information that is often involved.

The Plant Research Unit (PRU) is the Space Station Biological Research Program plant growth facility being developed for the International Space Station. The plant habitat is designed for experiments in near-zero gravity or it can be rotated by the ISS Centrifuge for experiments at any gravity level from microgravity to twice Earth's gravity. Plant experimentation will be possible in multiple Plant Research Units at one time, isolating the effect of gravity on the biological specimens. The PRU will provide and control all aspects of a plant's needs in a nearly closed system. In other words, the shoot and root environments will not be open to the astronaut's environment except for experiment maintenance such as planting, harvesting and plant sampling. This also means that all lighting, temperature and humidity control, nutrient delivery, and air filtering and cleaning must be done in a very small volume, with very little mass and power usage and with minimal crew time.

A system was developed which provides nutrients and water to plants while maintaining good aeration at the roots and preventing water from escaping in reduced gravity. The nutrient solution is circulated through porous tubes under negative pressure and moves through the tube wall via capillary forces into the rooting matrix, establishing a non-saturated condition in the root zone. Tests using prototypes of the porous tube water and nutrient delivery system indicate that plant productivity in this system is equivalent to standard soil and solution culture growing procedures. The system has functioned successfully in short-term microgravity during parabolic flight tests and will be flown on the space shuttle. Plants are one of the components of a bioregenerative life support system required for long duration space missions.

The ASTROCULTURE™ (ASC) middeck flight experiment series was developed to test subsystems required to grow plants in reduced gravity, with the goal of developing a plant growth unit suitable for conducting quality biological research in microgravity. Previous Space Shuttle flights (STS-50 and STS-57) have successfully demonstrated the ability to control water movement through a particulate rooting matrix in microgravity and the ability of LED lighting systems to provide high levels of irradiance without excessive heat build-up in microgravity. The humidity and temperature control system used in the middeck flight unit is described in this paper. The system controls air flow and provides dehumidification, humidification, and condensate recovery for a plant growth chamber volume of 1450 cm3.

The adaptation to changes in human operator dynamics and changes in working environment dynamics can be an important issue in designing high performance telerobotic systems. This paper describes an approach to force control in telerobotic hand systems in which model reference adaptive control techniques are used to adapt to changes in human operator and working environment dynamics. The techniques have been applied to force-reflective control of a single degree-of-freedom telerobotic gripper system at Wisconsin Center for Space Automation and Robotics (WCSAR). This adaptive gripping system is described in the paper along with results of experiments with human subjects in which the performance of the adaptive system was analysed and compared to the performance of a conventional non-adaptive system. These experiments emphasized adaptation to changes in compliance of gripped objects and adaptation to the on-set of human operator fatigue.

The ASTROCULTURE™ (ASC) middeck flight experiment series was developed to test and integrate subsystems required to grow plants in reduced gravity, with the goal of developing a plant growth unit suitable for conducting quality biological research in microgravity. Flights on the Space Shuttle have demonstrated control of water movement through a particulate rooting material, growth chamber temperature and humidity control, LED lighting systems and control, recycling of recovered condensate, ethylene scrubbing, and carbon dioxide control. A complete plant growth unit was tested on STS-63 in February 1995, the first ASC flight in which plant biology experiments were conducted in microgravity. The methods and objectives used for control of environmental conditions in the ASC unit are described in this paper.

Control of the flow of thermal energy in an air-cooled engine is important to the overall performance of the engine because of potential effects on engine performance, durability, design, and emissions. A methodology is being developed for the assessment of thermal flows in air-cooled engines, which includes the use of cycle simulation and in-cylinder heat flux measurements. The mechanism for the combination of cycle simulation, the measurement of in-cylinder heat flux and wall temperatures, and comparison of predicted and measured heat flux in the methodology is presented. The methodology consists of both simulation and experimental phases. To begin, a one-dimensional gas dynamics code (WAVE) has been used in conjunction with a detailed in-cylinder flow and combustion model (IRIS) in order to simulate engine operation in a variety of operating conditions. The methods used to apply the model to the air-cooled engine case are described in detail.

The Advanced Animal Habitat (AAH) represents the next generation of Space Station based animal research facilities. Building upon previously developed flight hardware and experience, the AAH offers greatly enhanced system capabilities and performance. The design focuses upon the creation of a robust and flexible platform capable of supporting present and future experimental needs. A modular packaging and distributed control architecture leads to increased system adaptability and expandability. The baseline configuration includes group housing capability for up to six rats with automated food and water delivery as well as waste collection. Animals are continuously monitored with three cameras during both day and night cycles. The animals can be accessed while on-orbit through the Life Sciences Glovebox to perform a wide variety of experimental protocols.

The Advanced Animal Habitat (AAH) and Plant Research Unit (PRU) are two major components of the Space Station Biological Research Project (SSBRP). These two habitats are currently under development by Orbital Technologies Corporation (ORBITEC). Science Evaluation Units (SEUs) have been developed for each of these habitats to allow investigators to plan and test flight experiments on the ground using hardware that is functionally similar to the flight versions of the AAH and PRU. The SEUs also contain key functionality that makes them excellent science tools for general laboratory experiments that are not related to flight experiments.

The VEGGIE unit is a deployable, low-resource plant growth system that can provide a source of fresh food and crew recreation on long duration space missions. VEGGIE can be stowed in 10% of its deployed volume; a single middeck locker equivalent can stow 1.0m2 of growing area. To reduce complexity, VEGGIE utilizes the ambient environment for temperature control and as a source of CO2. The lighting subsystem uses LEDs that provide a minimum light level of 300 µmol m−2s−1, spectral quality control, and a long operating life in a low profile package. The root zone is a compressible fabric mat. Each VEGGIE module has 0.17 m2 of growing area and can be varied in height from 5 to 45 cm. The mass, including the lighting subsystem and root mat, is 4.7 kg. On the ISS, VEGGIE can mount in the aisle, or in an EXPRESS rack.

The Advanced Animal Habitat (AAH) represents the next generation of Space Station based animal research facilities. Care has been taken to protect the ISS crew from exposure to the hazardous biological materials contained within the AAH. These materials include rat feces, urine, dander, and odor. The approach to containing biological materials relies on collecting the solid and liquid waste, providing physical barriers between the waste and the crew environment, maintaining negative pressure within the specimen environment with respect to the crew environment, and providing odor filtration of air exchanged between the specimen and crew environments. These protections will be in place during all modes of AAH operation.

A common question for students to ask educators is “When am I ever going to use this?” An excellent way to answer that question is to demonstrate how interrelated many subjects are. At ORBITEC in Madison, WI, we are developing systems to help teachers demonstrate the exciting interrelationships of science, math and technology using activities related to growing plants in space. We are developing two portable plant growth systems that integrate multiple disciplines, enriching students’ classroom experiences. Each portable growth unit is based on similar principles. The Space Garden and Biomass Production Education System (BPES) are growth units for indoor use that utilize a bellows technology to create a greenhouse-like environment. The Space Garden is a personal growth unit that a student can use individually while the BPES will be 0.25 m2, allowing larger-scale experimentation. The Space Garden will be best used in classrooms of grades four through seven.