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The goal of this interview analysis was to explore and document the perceptions of two unique lane centering systems (S90’s Pilot Assist and CT6’s Super Cruise). Both systems offer a similar type of functionality (adaptive cruise control and lane centering), but have significantly different design philosophies and HMI (Human-Machine Interface) implementations. Twenty-four drivers drove one of the two vehicle models for a month as part of a field operational test (FOT) study. Upon vehicle return, drivers took part in a 60-minute semi-structured interview covering their perceptions of the vehicle’s various advanced driver-assistance systems (ADAS). Transcripts of the interviews were coded by two researchers, who tagged each statement with relevant system and perception code labels. For analysis, the perception codes were grouped into larger thematic bins of safety, comfort, driver attention, and system performance.

A set of devices for measurement of human balance orientation and eye movements in weightlessness was developed for neurovestibular experiments on Spacelab. The experiments involve astronaut motion, limb position changes, and moving visual fields, measurements are made of eye movements, muscular activity and orientation perception. This joint US/Canadian research program represent a group of closely related experiments designed to investigate space motion sickness, any associated changes in otolith-mediated responses occurring during weightlessness, and the continuation of changes to postflight conditions. The otoliths are a component of the vestibular apparatus which is located in the middle ear. It is responsible for maintaining the body's balance. Gravitational pull on the otoliths causes them to constantly appraise the nervous system of the position of the head with respect to the direction of gravity.

The fuel energy consumption of subsonic air transportation is examined. The focus is on identification and quantification of fundamental engineering design tradeoffs which drive the design of subsonic tube and wing transport aircraft. The sensitivities of energy efficiency to recent and forecast technology developments are also examined.

The Lunar-Mars Life Support Test Project (LMLSTP) Phase III test examined the use of biological and physicochemical life support technologies for the recovery of potable water from waste water, the regeneration of breathable air, and the maintenance of a shirt-sleeve environment for a crew of four persons for 91 days. This represents the longest duration ground-test of life support systems with humans performed in the United States. This paper will describe the test from the inside viewpoint, concentrating on three major areas: maintenance and repair of life support elements, the scientific projects performed primarily in support of the International Space Station, and numerous activities in the areas of public affairs and education outreach.

When designing any human-system interface, it is critical to provide realistic anthropometry to properly represent how a person fits within a given space. This study aimed to identify a minimum number of ‘boundary manikins’ or representative models of subjects' anthropometry from a target population, which would realistically represent the population. The boundary manikin anthropometry was derived using, Principal Component Analysis (PCA). PCA is a statistical approach to reduce a multi-dimensional dataset using eigenvectors and eigenvalues. The measurements used in the PCA were identified as those measurements critical for space suit and cockpit design. The PCA yielded a total of 26 manikins per gender, as well as their anthropometry from the target population. Reduction techniques were implemented to reduce this number further with a final result of 20 female and 22 male subjects.

The International Space Station (ISS) Node 1 Environmental Control and Life Support (ECLS) System is comprised of five subsystems: Atmosphere Control and Supply (ACS), Atmosphere Revitalization (AR), Fire Detection and Suppression (FDS), Temperature and Humidity Control (THC), and Water Recovery and Management (WRM). This paper provides a summary of the Node 1 ECLS WRM subsystem design and a detailed discussion of the ISS ECLS Acceptance Testing methodology utilized for that subsystem.

With the long anticipated change to increase the International Space Station (ISS) crew size from three to six crew members and the retirement of the Space Shuttle, changes are in work to the International Space Station (ISS) Environmental Control and Life Support (ECLS) System to support the increased on-orbit crew size and their continued operations. The Space Shuttle had provided high pressure oxygen resupply, high pressure nitrogen resupply, water resupply, atmosphere gaseous make up when the Space Shuttle is docked to ISS, and logistic cargo supply/return capability to ISS. Without the Space Shuttle additional changes need to be made to the ISS ECLS System to support the six crew members post Assembly Complete (AC). This will be in addition to the changes that were needed to support doubling the nominal ISS crew size from three to six crew members.

The International Space Station (ISS) Pressurized Mating Adapters (PMAs) Environmental Control and Life Support (ECLS) System is comprised of three subsystems: Atmosphere Control and Supply (ACS), Temperature and Humidity Control (THC), and Water Recovery and Management (WRM). PMAs 1 and 2 flew to ISS on Flight 2A and Pressurized Mating Adapter (PMA) 3 flew to ISS on Flight 3A. This paper provides a summary of the PMAs ECLS design and a detailed discussion of the ISS ECLS Acceptance Testing methodologies utilized for the PMAs.

The International Space Station (ISS) Environmental Control and Life Support (ECLS) system includes regenerative and non-regenerative technologies that provide the basic life support functions to support the crew, while maintaining a safe and habitable shirtsleeve environment. This paper provides a summary of the U.S. ECLS system activities over the past year, covering the period of time between March 2007 and February 2008. The ISS continued permanent crew operations, with the continuation of Phase 3 of the ISS Assembly Sequence. Work continues on the last of the Phase 3 pressurized elements and the continued manufacturing and testing of the regenerative ECLS equipment.

Orion is the next vehicle for human space travel. Humans will be sustained in space by the Orion subystem, environmental control and life support (ECLS). The ECLS concept at the subsystem level is outlined by function and technology. In the past two years, the interface definition with other subsystems has increased through different integrated studies. The paper presents the key requirements and discusses three recent studies (e.g., unpressurized cargo) along with the respective impacts on the ECLS design moving forward.

The International Space Station (ISS) Environmental Control and Life Support (ECLS) system includes regenerative and non-regenerative technologies that provide the basic life support functions to support the crew, while maintaining a safe and habitable shirtsleeve environment. This paper provides a summary of the U.S. ECLS system activities over the past year, covering the period of time between March 2008 and February 2009. The ISS continued permanent crew operations, with the continuation of Phase 3 of the ISS Assembly Sequence. Work continues on the last of the Phase 3 pressurized elements and the continued manufacturing and testing of the regenerative ECLS equipment.

The aim of this study was to explore if fingernail delamination injury following EMU glove use may be caused by compression-induced blood flow occlusion in the finger. During compression tests, finger blood flow decreased more than 60%, however this occurred more rapidly for finger pad compression (4 N) than for fingertips (10 N). A pressure bulb compression test resulted in 50% and 45% decreased blood flow at 100 mmHg and 200 mmHg, respectively. These results indicate that the finger pad pressure required to articulate stiff gloves is more likely to contribute to injury than the fingertip pressure associated with tight fitting gloves.

NASA's next generation of space suit systems will place new demands on the pump used to circulate cooling water through the life support system and the crew's liquid cooling garment. Long duration missions and frequent EVA require increased durability and reliability; limited resupply mass requirements demand compatibility with recycled water, and changing system design concepts demand increased tolerance for dissolved and free gas and the ability to operate over a broader range of flow rates and discharge pressure conditions. This paper describes the development of a positive displacement prototype pump to meet these needs. A gerotor based design has been adapted to meet pump performance, gas tolerance, and durability requirements while providing a small, lightweight pump assembly. This design has been detailed and implemented using materials selected to address anticipated water quality and mission needs as a prototype unit for testing in NASA laboratories.

A work envelope has been defined for weightless Extravehicular Activity (EVA) based on the Space Shuttle Extravehicular Mobility Unit (EMU), but there is no equivalent for planetary operations. The weightless work envelope is essential for planning all EVA tasks because it determines the location of removable parts, making sure they are within reach and visibility of the suited crew member. In addition, using the envelope positions the structural hard points for foot restraints that allow placing both hands on the job and provides a load path for reacting forces. EVA operations are always constrained by time. Tasks are carefully planned to ensure the crew has enough breathing oxygen, cooling water, and battery power. Planning first involves computers using a virtual work envelope to model tasks, next suited crew members in a simulated environment refine the tasks.

This paper describes work that has begun at Ames Research Center on development of a heat melt compactor that can be used on near term and future missions. The heat melt compactor can handle wastes with a significant plastic composition and minimize crew interaction. The current solid waste management system employed on the International Space Station (ISS) consists of compaction, storage, and disposal. Wastes such as plastic food packaging and trash are compacted manually and wrapped in duct taped “footballs” by the astronauts. Much of the waste is simply loaded into the empty Russian Progress spacecraft that is used to bring supplies to ISS. The progress spacecraft and its contents are intentionally burned up in the earth's atmosphere during reentry. This manual method of trash management on ISS is a wasteful use of crew time and does not transition well to far term missions.

In an effort to define and advance the new discipline of Space Architecture, the AIAA technical subcommittee on Aerospace Architecture organized a Space Architecture Workshop that took place during the World Space Congress 2002 in Houston, Texas. One of the results of this workshop is a “Mission Statement for Space Architecture” that addresses the following core issues in a concise manner: definition, motivation, utility, required knowledge, and related disciplines. The workshop also addressed the typology and principles of space architecture, as well as basic philosophical guidelines for practitioners of this discipline. The mission statement, which was unanimously adopted by the workshop participants, reads as follows ([1], [2], [3]): “Space Architecture is the theory and practice of designing and building inhabited environments in outer space, responding to the deep human drive to explore and occupy new places.

The International Space Station (ISS) Environmental Control and Life Support (ECLS) system includes regenerative and non-regenerative technologies that provide the basic life support functions to support the crew, while maintaining a safe and habitable shirtsleeve environment. This paper provides a summary of the U.S. ECLS system activities over the past year, covering the period of time between April 2002 and March 2003. The ISS continued permanent crew operations, with the start of Phase 3 of the ISS Assembly Sequence. Work continued on the Phase 3 pressurized elements with Node 3 just completing its final design review so that it can proceed towards manufacturing and the continued manufacturing of the regenerative ECLS equipment that will be integrated into Node 3.

The International Space Station (ISS) Environmental Control and Life Support (ECLS) system includes regenerative and non-regenerative technologies that provide the basic life support functions to support the crew, while maintaining a safe and habitable shirtsleeve environment. This paper provides a summary of the ECLS System On-Orbit Station Development Test Objective (SDTO) status from the start of assembly until the end of February 2003.

The Advanced Life Support Research and Technology Development Metric, or Metric, for Government Fiscal Year 2002 provides a measure of the equivalent system mass for a life support system using the “best” available advanced technologies compared to the equivalent system mass for a life support system using technologies from International Space Station. The present paper details the assumed life support system configurations and algorithm used to compute the Metric. Additionally, various peripheral issues of importance are mentioned.

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.