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NASA NTRS2010

Technical Information/Website Preservation

This document reviews the work of the author in NASA's Motivating Undergraduates in Science and Technology (MUST) internship. The intern worked on the Space Shuttles hydraulic systems (i.e., Auxiliary Power Units (APU's) and Hydraulic Pump Units (HPU's)), and website preservation of the hydraulic technology captured in websites relating to the coming.the Space Shuttle Retirement. Several figures and pictures show an overview of the orbiter's hydraulic systems

PintoRey, Christian R.↗
NASA NTRS2010

Evaluating the Medical Kit System for the International Space Station(ISS) - A Paradigm Revisited

Medical capabilities aboard the International Space Station (ISS) have been packaged to help astronaut crew medical officers (CMO) mitigate both urgent and non-urgent medical issues during their 6-month expeditions. Two ISS crewmembers are designated as CMOs for each 3-crewmember mission and are typically not physicians. In addition, the ISS may have communication gaps of up to 45 minutes during each orbit, necessitating medical equipment that can be reliably operated autonomously during flight. The retirement of the space shuttle combined with ten years of manned ISS expeditions led the Space Medicine Division at the NASA Johnson Space Center to reassess the current ISS Medical Kit System. This reassessment led to the system being streamlined to meet future logistical considerations with current Russian space vehicles and future NASA/commercial space vehicle systems. Methods The JSC Space Medicine Division coordinated the development of requirements, fabrication of prototypes, and conducted usability testing for the new ISS Medical Kit System in concert with implementing updated versions of the ISS Medical Check List and associated in-flight software applications. The teams constructed a medical kit system with the flexibility for use on the ISS, and resupply on the Russian Progress space vehicle and future NASA/commercial space vehicles. Results Prototype systems were developed, reviewed, and tested for implementation. Completion of Preliminary and Critical Design Reviews resulted in a streamlined ISS Medical Kit System that is being used for training by ISS crews starting with Expedition 27 (June 2011). Conclusions The team will present the process for designing, developing, , implementing, and training with this new ISS Medical Kit System.

Hailey, Melinda J.↗
NASA NTRS2010

NASA Astronaut Selection 2009: Behavioral Overview

NASA's multi-phase U.S. astronaut selection process seeks to identify the most qualified astronaut candidates from a large number of applicants. With the approaching retirement of the Space Shuttle, NASA focused on selecting those individuals who were most suited to the unique demands of long-duration spaceflight. In total, NASA received 3,535 applications for the 2009 astronaut selection cycle. Of these, 123 were invited to NASA Johnson Space Center (JSC) for Round 1 initial screening and interviews, which consisted of an Astronaut Selection Board (ASB) preliminary interview, medical review, and psychological testing. Of these, 48 individuals were invited to return for Round 2. This round consisted of medical testing, further behavioral assessments, and a second ASB interview. Following this, nine astronaut candidates (ASCANs) were ultimately chosen to go forward to basic training. The contents, benefits, and lessons learned from implementing this phased process will be discussed. The lessons learned can benefit the future selection of space flyers, whether they are NASA or commercial. Learning Objective: 1) Familiarization with the 2009 NASA behavioral screening process for astronaut applicants.

Holland, A. W.↗
NASA NTRS2010

Ensuring US National Aeronautics Test Capabilities

U.S. leadership in aeronautics depends on ready access to technologically advanced, efficient, and affordable aeronautics test capabilities. These systems include major wind tunnels and propulsion test facilities and flight test capabilities. The federal government owns the majority of the major aeronautics test capabilities in the United States, primarily through the National Aeronautics and Space Administration (NASA) and the Department of Defense (DoD). However, changes in the Aerospace landscape, primarily the decrease in demand for testing over the last 20 years required an overarching strategy for management of these national assets. Therefore, NASA established the Aeronautics Test Program (ATP) as a two-pronged strategic initiative to: (1) retain and invest in NASA aeronautics test capabilities considered strategically important to the agency and the nation, and (2) establish a strong, high level partnership with the DoD. Test facility utilization is a critical factor for ATP because it relies on user occupancy fees to recover a substantial part of the operations costs for its facilities. Decreasing utilization is an indicator of excess capacity and in some cases low-risk redundancy (i.e., several facilities with basically the same capability and overall low utilization). However, low utilization does not necessarily translate to lack of strategic importance. Some facilities with relatively low utilization are nonetheless vitally important because of the unique nature of the capability and the foreseeable aeronautics testing needs. Unfortunately, since its inception, the customer base for ATP has continued to shrink. Utilization of ATP wind tunnels has declined by more than 50% from the FY 2006 levels. This significant decrease in customer usage is attributable to several factors, including the overall decline in new programs and projects in the aerospace sector; the impact of computational fluid dynamics (CFD) on the design, development, and research process; and the reductions in wind tunnel testing requirements within the largest consumer of ATP wind tunnel test time, the Aeronautics Research Mission Directorate (ARMD). Retirement of the Space Shuttle Program and recent perturbations of NASA's Constellation Program will exacerbate this downward trend. Therefore it is crucial that ATP periodically revisit and determine which of its test capabilities are strategically important, which qualify as low-risk redundancies that could be put in an inactive status or closed, and address the challenges associated with both sustainment and improvements to the test capabilities that must remain active. This presentation will provide an overview of the ATP vision, mission, and goals as well as the challenges and opportunities the program is facing both today and in the future. We will discuss the strategy ATP is taking over the next five years to address the National aeronautics test capability challenges and what the program will do to capitalize on its opportunities to ensure a ready, robust and relevant portfolio of National aeronautics test capabilities.

Marshall, Timothy J.↗
NASA NTRS2010

Commercial Orbital Transportation Cargo Services Environmental Control and Life Support Integration

The International Space Station s (ISS) largest crew and cargo resupply vehicle, the Space Shuttle, will retire in 2011. To help augment ISS resupply and return capability, NASA announced a project to promote the development of Commercial Orbital Transportation Services (COTS) for the ISS in January of 2006. By December of 2008, NASA entered into space act agreements with SpaceX and Orbital Sciences Corporation for COTS development and ISS Commercial Resupply Services (CRS). The intent of CRS is to fly multiple resupply missions each year to ISS with SpaceX s Dragon vehicle providing resupply and return capabilities and Orbital Science Corporation s Cygnus vehicle providing resupply capability to ISS. The ISS program launched an integration effort to ensure that these new commercial vehicles met the requirements of the ISS vehicle and ISS program needs. The Environmental Control and Life Support System (ECLSS) requirements cover basic cargo vehicle needs including maintaining atmosphere, providing atmosphere circulation, and fire detection and suppression. The ISS-COTS integration effort brought unique challenges combining NASA s established processes and design knowledge with the commercial companies new initiatives and limited experience with human space flight. This paper will discuss the ISS ECLS COTS integration effort including challenges, successes, and lessons learned.

Duchesne, Stephanie↗
NASA NTRS2010

Cold Stowage Flight Systems

The International Space Station (ISS) provides a test bed for researchers to perform science experiments in a variety of fields, including human research, life sciences, and space medicine. Many of the experiments being conducted today require science samples to be stored and transported in a temperature controlled environment. NASA provides several systems which aide researchers in preserving their science. On orbit systems provided by NASA include the Minus Eighty Laboratory freezer for ISS (MELFI), Microgravity Experiment Research Locker Incubator (MERLIN), and Glacier. These freezers use different technologies to provide rapid cooling and cold stowage at different temperature levels on board ISS. Systems available to researchers during transportation to and from ISS are MERLIN, Glacier, and Coldbag. Coldbag is a passive cold stowage system that uses phase change materials. Details of these current technologies will be provided along with operational experience gained to date. With shuttle retirement looming, NASA has protected the capability to provide a temperature controlled environment during transportation to and from the ISS with the use of Glacier and Coldbags, which are compatible with future commercial vehicles including SpaceX's Dragon Capsule, and Orbital s Cygnus vehicle. This paper will discuss the capability of the current cold stowage hardware and how it may continue to support NASA s mission on ISS and in future exploration missions.

Campana, Sharon↗
NASA NTRS2010

U.S. Spacesuit Knowledge Capture

The ability to learn from both the mistakes and successes of the past is vital to assuring success in the future. Due to the close physical interaction between spacesuit systems and human beings as users, spacesuit technology and usage lends itself rather uniquely to the benefits realized from the skillful organization of historical information; its dissemination; the collection and identification of artifacts; and the education of individuals and groups working in the field. The National Aeronautics and Space Administration (NASA), other organizations and individuals have been performing United States (U.S.) spacesuit knowledge capture since the beginning of space exploration. Avenues used to capture the knowledge have included publication of reports; conference presentations; specialized seminars; and classes usually given by veterans in the field. Recently, the effort has been more concentrated and formalized whereby a new avenue of spacesuit knowledge capture has been added to the archives through which videotaping occurs, engaging both current and retired specialists in the field presenting technical scope specifically for education and preservation of knowledge. Now with video archiving, all these avenues of learning can be brought to life with the real experts presenting their wealth of knowledge on screen for future learners to enjoy. U.S. spacesuit knowledge capture topics have included lessons learned in spacesuit technology, experience from the Gemini, Apollo, Skylab and Shuttle programs, hardware certification, design, development and other program components, spacesuit evolution and experience, failure analysis and resolution, and aspects of program management. Concurrently, U.S. spacesuit knowledge capture activities have progressed to a level where NASA, the National Air and Space Museum (NASM), Hamilton Sundstrand (HS) and the spacesuit community are now working together to provide a rather closed-looped spacesuit knowledge capture system which includes specific attention to spacesuit system artifacts as well. A NASM report has recently been created that allows the cross reference of history to the artifacts and the artifacts to the history including spacesuit manufacturing details with current condition and location. NASA has examined spacesuits in the NASM collection for evidence of wear during their operational life. NASA s formal spacesuit knowledge capture efforts now make use of both the NASM spacesuit preservation collection and report to enhance its efforts to educate NASA personnel and contribute to spacesuit history. Be it archiving of human knowledge or archiving of the actual spacesuit legacy hardware with its rich history, the joining together of spacesuit system artifact history with that of development and use during past programs will provide a wealth of knowledge which will greatly enhance the chances for the success of future and more ambitious spacesuit system programs.

Chullen, Cinda↗
NASA NTRS2010

Product Lifecycle Management and the Quest for Sustainable Space Explorations

Product Lifecycle Management (PLM) is an outcome of lean thinking to eliminate waste and increase productivity. PLM is inextricably tied to the systems engineering business philosophy, coupled with a methodology by which personnel, processes and practices, and information technology combine to form an architecture platform for product design, development, manufacturing, operations, and decommissioning. In this model, which is being implemented by the Engineering Directorate at the National Aeronautics and Space Administration's (NASA's) Marshall Space Flight Center, total lifecycle costs are important variables for critical decision-making. With the ultimate goal to deliver quality products that meet or exceed requirements on time and within budget, PLM is a powerful concept to shape everything from engineering trade studies and testing goals, to integrated vehicle operations and retirement scenarios. This paper will demonstrate how the Engineering Directorate is implementing PLM as part of an overall strategy to deliver safe, reliable, and affordable space exploration solutions. It has been 30 years since the United States fielded the Space Shuttle. The next generation space transportation system requires a paradigm shift such that digital tools and knowledge management, which are central elements of PLM, are used consistently to maximum effect. The outcome is a better use of scarce resources, along with more focus on stakeholder and customer requirements, as a new portfolio of enabling tools becomes second nature to the workforce. This paper will use the design and manufacturing processes, which have transitioned to digital-based activities, to show how PLM supports the comprehensive systems engineering and integration function. It also will go through a launch countdown scenario where an anomaly is detected to show how the virtual vehicle created from paperless processes will help solve technical challenges and improve the likelihood of launching on schedule, with less hands-on labor needed for processing and troubleshooting.

Caruso, Pamela W.↗
NASA NTRS2010

How NASA Expanded its Innovation Framework to Find New Solutions to Old Problems

A radio frequency engineer from rural New Hampshire contributed the best solution to a public challenge issued by NASA's Space Life Sciences Directorate. This is a clear example of what Aneesh Chopra, the US Federal Chief Technology Officer, describes as the notion that in our society, knowledge is widely dispersed. And if it s widely dispersed, how do we capture the insights from the American people?" Chopra later said, to a live audience at the 2010 Rethinking Government event: "A semi-retired radio frequency engineer was able to share his idea about how to solve this problem, and it so blew away other ideas that NASA said it exceeded their requirements! No complicated RFP, the need for lobbyists, some convoluted processes, etc. Just a smart person who was paid a modest fee for his insight."

Davis, Jeffrey R.↗
NASA NTRS2010

Failure Analysis of Fractured Poppet from Space Shuttle Orbiter Flow Control Valve

This slide presentation reviews the failure analysis of a fractured poppet from a flow control valve (FCV) used on the space shuttle. This presentation has focused on the laboratory analysis of the failed hardware. The use of Scanning electron fractography during the investigation led to the conclusion that the poppet failed due to fatigue cracking that, most likely, occurred under changing loading conditions. The initial investigation led to a more thorough test of poppets that had been retired, this testing led to the conclusion that the thumbnail cracks in the flight hardware had existed for the life of the shuttle program. This led to a program to develop an eddy current technique that was capable of detecting small very tight cracks.

Russell, Richard↗
NASA NTRS2011

Simplified Architecture for Precise Aiming of a Deep-Space Communication Laser Transceiver

The simplified architecture is a minimal system for a deep-space optical communications transceiver. For a deepspace optical communications link the simplest form of the transceiver requires (1) an efficient modulated optical source, (2) a point-ahead mechanism (PAM) to compensate for two-way light travel, (3) an aperture to reduce the divergence of the transmit laser communication signal and also to collect the uplink communication signal, and (4) a receive detector to sense the uplink communication signal. Additional components are introduced to mitigate for spacecraft microvibrations and to improve the pointing accuracy. The Canonical Transceiver implements this simplified architecture (see figure). A single photon-counting smart focal plane sensor combines acquisition, tracking, and forward link data detection functionality. This improves optical efficiency by eliminating channel splits. A transmit laser blind sensor (e.g. silicon with 1,550-nm beam) provides transmit beam-pointing feedback via the two-photon absorption (TPA) process. This vastly improves the transmit/receive isolation because only the focused transmit beam is detected. A piezoelectric tiptilt actuator implements the required point-ahead angle. This point-ahead mechanism has been demonstrated to have near zero quiescent power and is flight qualified. This architecture also uses an innovative 100-mHz resonant frequency passive isolation platform to filter spacecraft vibrations with voice coil actuators for active tip-tilt correction below the resonant frequency. The canonical deep-space optical communications transceiver makes synergistic use of innovative technologies to reduce size, weight, power, and cost. This optical transceiver can be used to retire risks associated with deep-space optical communications on a planetary pathfinder mission and is complementary to ongoing lunar and access link developments.

Ortiz, Gerard G.↗
NASA NTRS2010

Product Lifecycle Management and the Quest for Sustainable Space Exploration Solutions

Product Lifecycle Management (PLM) is an outcome of lean thinking to eliminate waste and increase productivity. PLM is inextricably tied to the systems engineering business philosophy, coupled with a methodology by which personnel, processes and practices, and information technology combine to form an architecture platform for product design, development, manufacturing, operations, and decommissioning. In this model, which is being implemented by the Engineering Directorate at the National Aeronautics and Space Administration's (NASA's) Marshall Space Flight Center, total lifecycle costs are important variables for critical decisionmaking. With the ultimate goal to deliver quality products that meet or exceed requirements on time and within budget, PLM is a powerful tool to shape everything from engineering trade studies and testing goals, to integrated vehicle operations and retirement scenarios. This paper will demonstrate how the Engineering Directorate is implementing PLM as part of an overall strategy to deliver safe, reliable, and affordable space exploration solutions. It has been 30 years since the United States fielded the Space Shuttle. The next generation space transportation system requires a paradigm shift such that digital tools and knowledge management, which are central elements of PLM, are used consistently to maximum effect. The outcome is a better use of scarce resources, along with more focus on stakeholder and customer requirements, as a new portfolio of enabling tools becomes second nature to the workforce. This paper will use the design and manufacturing processes, which have transitioned to digital-based activities, to show how PLM supports the comprehensive systems engineering and integration function. It also will go through a launch countdown scenario where an anomaly is detected to show how the virtual vehicle created from paperless processes will help solve technical challenges and improve the likelihood of launching on schedule, with less hands-on labor needed for processing and troubleshooting. Sustainable space exploration solutions demand that all lifecycle phases be optimized. Adopting PLM, which has been used by the automotive industry for many years, for aerospace applications provides a foundation for strong, disciplined systems engineering and accountable return on investment by making lifecycle considerations variables in an iterative decision-making process. This paper combines the perspectives of the founding father of PLM, along with the experience of Engineering leaders who are implementing these processes and practices real-time. As the nation moves from an industrial-based society to one where information is a valued commodity, future NASA programs and projects will benefit from the experience being gained today for the exploration missions of tomorrow.

Caruso, Pamela W.↗
NASA NTRS2011

NASA Mission Operations Directorate Preparations for the COTS Visiting Vehicles

With the retirement of the Space Shuttle looming, a series of new spacecraft is under development to assist in providing for the growing logistical needs of the International Space Station (ISS). Two of these vehicles are being built under a NASA initiative known as the Commercial Orbital Transportation Services (COTS) program. These visiting vehicles ; Space X s Dragon and Orbital Science Corporation s Cygnus , are to be domestically produced in the United States and designed to add to the capabilities of the Russian Progress and Soyuz workhorses, the European Automated Transfer Vehicle (ATV) and the Japanese H-2 Transfer Vehicle (HTV). Most of what is known about the COTS program has focused on the work of Orbital and SpaceX in designing, building, and testing their respective launch and cargo vehicles. However, there is also a team within the Mission Operations Directorate (MOD) at NASA s Johnson Space Center working with their operational counterparts in these companies to provide operational safety oversight and mission assurance via the development of operational scenarios and products needed for these missions. Ensuring that the operational aspect is addressed for the initial demonstration flights of these vehicles is the topic of this paper. Integrating Dragon and Cygnus into the ISS operational environment has posed a unique challenge to NASA and their partner companies. This is due in part to the short time span of the COTS program, as measured from initial contract award until first launch, as well as other factors that will be explored in the text. Operational scenarios and products developed for each COTS vehicle will be discussed based on the following categories: timelines, on-orbit checkout, ground documentation, crew procedures, software updates and training materials. Also addressed is an outline of the commonalities associated with the operations for each vehicle. It is the intent of the authors to provide their audience with a better understanding of the mission assurance that MOD brings to commercial ventures to the ISS

Shull, Sarah A.↗
NASA NTRS2011

Space Shuttle Day-of-Launch Trajectory Design Operations

A top priority of any launch vehicle is to insert as much mass into the desired orbit as possible. This requirement must be traded against vehicle capability in terms of dynamic control, thermal constraints, and structural margins. The vehicle is certified to specific structural limits which will yield certain performance characteristics of mass to orbit. Some limits cannot be certified generically and must be checked with each mission design. The most sensitive limits require an assessment on the day-of-launch. To further minimize vehicle loads while maximizing vehicle performance, a day-of-launch trajectory can be designed. This design is optimized according to that day s wind and atmospheric conditions, which increase the probability of launch. The day-of-launch trajectory design and verification process is critical to the vehicle s safety. The Day-Of-Launch I-Load Update (DOLILU) is the process by which the National Aeronautics and Space Administration's (NASA) Space Shuttle Program tailors the vehicle steering commands to fit that day s environmental conditions and then rigorously verifies the integrated vehicle trajectory s loads, controls, and performance. This process has been successfully used for almost twenty years and shares many of the same elements with other launch vehicles that execute a day-of-launch trajectory design or day-of-launch trajectory verification. Weather balloon data is gathered at the launch site and transmitted to the Johnson Space Center s Mission Control. The vehicle s first stage trajectory is then adjusted to the measured wind and atmosphere data. The resultant trajectory must satisfy loads and controls constraints. Additionally, these assessments statistically protect for non-observed dispersions. One such dispersion is the change in the wind from the last measured balloon to launch time. This process is started in the hours before launch and is repeated several times as the launch count proceeds. Should the trajectory design not meet all constraint criteria, Shuttle would be No-Go for launch. This Shuttle methodology is very similar to other unmanned launch vehicles. By extension, this method would likely be employed for any future NASA launch vehicle. This paper will review the Shuttle s day-of-launch trajectory optimization and verification operations as an example of a more generic application of day-of-launch design and validation. With Shuttle s retirement, it is fitting to document the current state of this critical process and capture lessons learned to benefit current and future launch vehicle endeavors.

Harrington, Brian E.↗
NASA NTRS2011

A Bootstrap Approach to an Affordable Exploration Program

This paper examines the potential to build an affordable sustainable exploration program by adopting an approach that requires investing in technologies that can be used to build a space infrastructure from very modest initial capabilities. Human exploration has had a history of flight programs that have high development and operational costs. Since Apollo, human exploration has had very constrained budgets and they are expected be constrained in the future. Due to their high operations costs it becomes necessary to consider retiring established space facilities in order to move on to the next exploration challenge. This practice may save cost in the near term but it does so by sacrificing part of the program s future architecture. Human exploration also has a history of sacrificing fully functional flight hardware to achieve mission objectives. An affordable exploration program cannot be built when it involves billions of dollars of discarded space flight hardware, instead, the program must emphasize preserving its high value space assets and building a suitable permanent infrastructure. Further this infrastructure must reduce operational and logistics cost. The paper examines the importance of achieving a high level of logistics independence by minimizing resource consumption, minimizing the dependency on external logistics, and maximizing the utility of resources available. The approach involves the development and deployment of a core suite of technologies that have minimum initial needs yet are able expand upon initial capability in an incremental bootstrap fashion. The bootstrap approach incrementally creates an infrastructure that grows and becomes self sustaining and eventually begins producing the energy, products and consumable propellants that support human exploration. The bootstrap technologies involve new methods of delivering and manipulating energy and materials. These technologies will exploit the space environment, minimize dependencies, and minimize the need for imported resources. They will provide the widest range of utility in a resource scarce environment and pave the way to an affordable exploration program.

Oeftering, Richard C.↗
NASA NTRS2011

In-Suit Light Exercise (ISLE) Prebreathe Protocol Peer Review Assessment

The performance of extravehicular activity (EVA) by National Aeronautics and Space Administration astronauts involves the risk of decompression sickness. This risk has been mitigated by the use of oxygen "prebreathe" to effectively wash out tissue nitrogen prior to each EVA. Now that the Space Shuttle Program (SSP) is being retired, high-pressure oxygen will become a limited resource. The In-Suit Light Exercise (ISLE) Prebreathe Protocol offers several potential benefits including its potential to save 6 pounds of oxygen per EVA. At the request of the NASA Engineering and Safety Center, the peer review convened on October 14, 2010. The major recommendation of the Review Committee was that the ISLE protocol was acceptable for operational use as a prebreathe option prior to EVA. The results from the peer review are contained in this document.

Brady, Timothy K.↗
NASA NTRS2011

Relaxing USOS Solar Array Constraints for Russian Vehicle Undocking

With the retirement of Space Shuttle cargo delivery capability and the ten year life extension of the International Space Station (ISS) more emphasis is being put on preservation of the service life of ISS critical components. Current restrictions on the United States Orbital Segment (USOS) Solar Array (SA) positioning during Russian Vehicle (RV) departure from ISS nadir and zenith ports cause SA to be positioned in the plume field of Service Module thrusters and lead to degradation of SAs as well as potential damage to Sun tracking Beta Gimbal Assemblies (BGA). These restrictions are imposed because of the single fault tolerant RV Motion Control System (MCS), which does not meet ISS Safety requirements for catastrophic hazards and dictates 16 degree Solar Array Rotary Joint position, which ensures that ISS and RV relative motion post separation, does lead to collision. The purpose of this paper is to describe a methodology and the analysis that was performed to determine relative motion trajectories of the ISS and separating RV for nominal and contingency cases. Analysis was performed in three phases that included ISS free drift prior to Visiting Vehicle separation, ISS and Visiting Vehicle relative motion analysis and clearance analysis. First, the ISS free drift analysis determined the worst case attitude and attitude rate excursions prior to RV separation based on a series of different configurations and mass properties. Next, the relative motion analysis calculated the separation trajectories while varying the initial conditions, such as docking mechanism performance, Visiting Vehicle MCS failure, departure port location, ISS attitude and attitude rates at the time of separation, etc. The analysis employed both orbital mechanics and rigid body rotation calculations while accounting for various atmospheric conditions and gravity gradient effects. The resulting relative motion trajectories were then used to determine the worst case separation envelopes during the clearance analysis. Analytical models were developed individually for each stage and the results were used to build initial conditions for the following stages. In addition to the analysis approach, this paper also discusses the analysis results, showing worst case relative motion envelopes, the recommendations for ISS appendage positioning and the suggested approach for future analyses.

Menkin, Evgeny↗