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NASA's plans to implement the Vision for Space Exploration include extensive human-robot cooperation across an enterprise spanning multiple missions, systems, and decades. To make this practical, strong enterprise-level interface standards (data, power, communication, interaction, autonomy, and physical) will be required early in the systems and technology development cycle. Such standards should affect both the engineer and operator roles that humans adopt in their interactions with robots. For the engineer role, standards will result in reduced development lead-times, lower cost, and greater efficiency in deploying such systems. For the operator role, standards will result in common autonomy and interaction modes that reduce operator training, minimize workload, and apply to many different robotic platforms. Reduced quantities of spare hardware could also be a benefit of standardization.

The Plant Research Unit (PRU) is currently under development by the Space Station Biological Research Project (SSBRP) team at NASA Ames Research Center (ARC) with a scheduled launch in 2001. The goal of the project is to provide a controlled environment that can support seed-to-seed and other plant experiments for up to 90 days. This paper describes testing conducted on the major PRU prototype subsystems. Preliminary test results indicate that the prototype subsystem hardware can meet most of the SSBRP science requirements within the Space Station mass, volume, power and heat rejection constraints.

Firefighters want to go to work, do their job well, and go home alive and uninjured. For their most important job, saving lives, firefighters want protective equipment that will allow more extended and effective time at fire scenes in order to perform victim search and rescue. A team, including engineers at NASA JSC and firefighters from Houston, has developed a list of problem areas for which NASA technology and know-how can recommend improvements for firefighter suits and gear. Prototypes for solutions have been developed and are being evaluated. This effort will spin back to NASA as improvements for lunar and planetary suits.

The On-line Project Information System (OPIS) is the Exploration Life Support (ELS) mechanism for task data sharing and annual reporting. Fiscal year 2008 (FY08) was the first year in which ELS Principal Investigators (PI's) were required to complete an OPIS annual report. The reporting process consists of downloading a template that is customized to the task deliverable type(s), completing the report, and uploading the document to OPIS for review and approval. In addition to providing a general status and overview of OPIS features, this paper describes the user critiques and resulting system modifications of the first year of OPIS reporting efforts. Specifically, this paper discusses process communication and logistics issues, user interface ambiguity, report completion challenges, and the resultant or pending system improvements designed to circumvent such issues for the fiscal year 2009 reporting effort.

The National Aeronautics and Space Administration (NASA) is working towards future long duration manned space flights beyond low earth orbit. For these missions several food provisioning strategies are being investigated. Individual, prepackaged meals may be provided throughout the mission or commodities may be taken in bulk and processed while on the planetary surface. To enable these different supply scenarios, a packaging system must be developed that will protect the food or commodity and have minimal impact on system mass. Metric values for a prepackaged scenario and a bulk supply scenario, using current packaging material technologies, were compared. The results of this comparison show that bulk packaging penalties will potentially be more than an order of magnitude less than those of a prepackaged food system.

Spacecraft hardware trade studies compare options primarily on mass while considering impacts to cost, risk, and schedule. Historically, other factors have been considered in these studies, such as reliability, technology readiness level (TRL), volume and crew time. In most cases, past trades compared two or more technologies across functional and TRL boundaries, which is an uneven comparison of the technologies. For example, low TRL technologies with low mass were traded directly against flight-proven hardware without consideration for requirements and the derived architecture. To provide for even comparisons of spacecraft hardware, trades need to consider functionality, mission constraints, integer vs. real number of flight hardware units, and mass growth allowances by TRL.

In this investigation, analytical models were developed to predict the performance characteristics of axisymmetric single jet ejector. The ejector is divided into four parts, jet, mixer, nozzle, and diffuser. Basic flow equations were combined to calculate end to end flow characteristics for each of the four ejector components. Different jets and mixer combination were tested using three jet and three mixers. Characteristics curves have been drawn to predict flow characteristics of the ejector. Different configuration of jet and mixer incorporated different loss coefficient. Hence to get correct flow characteristics of the ejector right loss coefficient should be used.

The Carbon Dioxide Removal Assembly (CDRA) on board the International Space Station (ISS) has experienced periodic check valve and selector valve failures as a result of a gradual build-up of contamination from particles that have breeched the adsorbent bed seals. The current software that controls CDRA has limitations that make troubleshooting the unit difficult in these situations, in large part due to the fact that valve position telemetry is only available during certain times. There are also situations where it is required to perform operations manually that would benefit from added code logic and commands to facilitate these operations. The software has been reviewed for possible upgrades and changes that will allow engineers to better troubleshoot the unit in the event of various failures and also allow for better operability in degraded states.

Significant system efficiency gains can be achieved in high-performance aircraft via a unitized structure that reduces parts count. For instance, reduced parts count leads to substantial engineering logistic cost savings through higher levels of subsystem and mounting hardware integration. It also creates performance benefits by eliminating structural connections. Residual stress management, however, remains a major obstacle to capturing full benefits and broadening the application of unitized structure solutions. This paper describes how Alcoa and others are developing tools to overcome limitations in current testing, evaluation, and design practices attributed to residual stress effects. The authors present recent advancements in fracture toughness and fatigue crack growth characterization, along with a new, integrated approach for improved accounting of residual stress effects during fracture critical component design, manufacturing planning, and life management.

A dynamic simulation of the ISS CDRA hardware was created using the Aspen Custom Modeler software platform. The dynamic model calculates the material and energy balances that describe the system properties. The model was calibrated by comparison to test data results from a flight-like CDRA at NASA Marshall Space Flight Center. While other FORTRAN models of the CDRA already exist, developing an ACM simulation is the first step towards creating a generic tool to simulate larger collections of life support hardware. The ACM tool should make it possible to be very flexible when rearranging these models to simulate possible configurations of the life support subsystems that could be used in the future, especially for advanced life support applications.

The Lunar Electric Rover (LER), which was formerly called the Small Pressurized Rover (SPR), is currently being carried as an integral part of the lunar surface architectures that are under consideration in the Constellation Program. One element of the LER is the suit port, which is the means by which crew members perform Extravehicular Activities (EVAs). Two suit port deliverables were produced in fiscal year 2008: a 1-g suit port concept evaluator for functional integrated testing with the LER 1-g concept vehicle and a functional and pressurizable Engineering Unit (EU). This paper focuses on the 1-g suit port concept evaluator test results from the Desert Research and Technology Studies (D-RATS) October 2008 testing at Black Point Lava Flow (BPLF), Arizona. The 1-g suit port concept evaluator was integrated with the 1-g LER cabin and chassis concepts.