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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.

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.

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 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.

High reliability and system flexibility are driving factors in the Plant Research Unit development. Proper selection of the unit electrical and software control architecture is fundamental to achieving these goals. Key features of the PRU control design include the use of a real time operating system for main process control, dynamic power management, a distributed control architecture and subsystem modularity. The chosen approach will allow future modifications and improvements to be incorporated at the subsystem level with minimal impact to the unit overall. Hardware fault tolerance and redundancy enhance system reliability.

The International Space Station (ISS) presents unique challenges in the field of maintainability engineering. Due to limited training time on earth and crew time in space, systems must be designed for ease of operation and maintenance. The Plant Research Unit (PRU), an advanced plant growth facility, is required to operate on orbit with minimal crew interaction for maintenance. The PRU has been allotted one hour per increment for corrective maintenance, which consists of replacing Orbital Replacement Units (ORU) or incorporating workarounds. Designing highly maintainable systems is not possible without incorporating the principles of human factors engineering. The PRU has met the strict crew time requirements by combining those principles with maintainability engineering analysis techniques and then integrating them in the design process.

The ECLSS (Environmentally Controlled Life Support System) project goals are to identify key requirements and guidelines for a Life Support System (LSS) for surface missions based on the Exploration Spirals, to review the various technology options and candidates to fulfill the life support functionality, and to conduct initial trades and assessments at a high level. With the completion of the first six month phase of the project, ORBITEC has generated and shown that for each Exploration Spiral, different LSS architectures are optimal, but when an entire mission model is considered, hybrid systems become more attractive. Also, we can easily show that future spiral requirements should and will influence the technologies and level of closure for earlier spiral developments to reduce overall development and implementation costs, and to increase commonality across the Constellation systems.

The wonder of space exploration is a sure way to catch the attention of students of all ages, and space biology is one of many sciences critical to understanding the spaceflight environment. Many systems used in the past for space-to-classroom biology activities have required extensive crew time and material resources, making space-linked education logistically and financially difficult. The new Education Payload Operations Kit C (EPO Kit C) aims to overcome obstacles to space-linked education and outreach by dramatically reducing the resources required for educational activities in plant space biology that have a true spaceflight component. EPO Kit C is expected to be flown from STS-118 to the International Space Station in June 2007. NASA and several other organizations are currently planning an outreach program to complement the flight of EPO Kit C.

Water recovery is essential for long-duration space exploration transit and outpost missions. Primary stage wastewater recovery systems partially satisfy this need, and generate concentrated wastewater brines that are unusable without further processing. The Enhanced Brine Dewatering System (EBDS) is being developed to allow nearly complete recovery of water from Lunar Outpost wastewater brines. This paper describes the operation of the EBDS and discusses the development and testing of the major functional materials, components, and subsystems, including the wastewater brine ersatz formulations that are used in subsystem testing. The assembly progress of the EBDS full system prototype is also discussed, as well as plans for testing the prototype hardware.

The Biomass Production System, recently flown on the ISS for 73 days, demonstrated significant advancements in functional performance over previous systems for conducting plant science in microgravity. The Biomass Production System (BPS) was the first flight of a system with multiple, independently controlled, plant growth chambers. Each of four chambers was controlled separately with respect to temperature, humidity, light level, nutrient level, and CO2, and all were housed in a double Middeck locker-sized payload. During the mission, each of the subsystems performed within specification. This paper focuses on how the performance of the BPS hardware allowed successful completion of the preflight objectives.

The longest BPS ground test to-date was the BPS Mission Verification Test done to provide a high fidelity end-to-end system test of BPS hardware and operations. This test took place at Kennedy Space Center from 4/9/01 to 6/21/01. The BPS temperature and humidity control, atmospheric control, lighting, and nutrient delivery systems performed within specifications. Ambient temperature conditions for the test ranged from 22°C to 28°C. Temperature systems performed well over the full range of ambient conditions and temperature setpoints were maintained throughout the test. Humidity setpoints were maintained within specification under nominal conditions; however, drift in humidity was observed during high ambient temperatures with large plant load conditions, and during CO2 drawdowns. CO2 levels in the wheat chambers were within ± 10% of setpoint under nominal conditions. Several automated CO2 drawdowns and CO2 cylinder changeouts were successfully completed.

The Biomass Production System (BPS) was flown on the ISS for 73 days as part of the Increment 4 mission. To obtain maximum benefit from the long mission duration, numerous manual crew procedures were incorporated into the BPS experiments. These procedures included gas sampling, root module priming, harvesting, pollination, filter cleaning, water refill, and water sampling. On-orbit crew assessments were filled out for each of these procedures to evaluate the ability of BPS to accommodate them. The assessment asked questions about each phase of an activity and solicited recommendations for improvements. Further analysis of most procedures was provided by detailed video made on-orbit and multiple post-flight crew debriefs. Most assessments indicated no need for improvements, but a number of crew suggestions will be incorporated into hardware and procedure updates.

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 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.