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The process of developing, parameterizing, validating, and maintaining models occurs within a wide variety of tools, and requires significant time and resources. To maximize model utilization, models are often shared between various toolsets and experts. One common example is sharing aircraft engine models with airframers. The functionality of a given model may be utilized and shared with a secondary model, or multiple models may run collaboratively through co-simulation. There are many technical challenges associated with model sharing and co-simulation. For example, data communication between models and tools must be accurate and reliable, and the model usage must be well-documented and perspicuous for a user. This requires clear communication and understanding between computer scientists and engineers. Most often, models are developed by engineers, whereas the tools used to share the models are developed by computer scientists.

Actuators are the key to allowing machines to become more sophisticated and perform complex tasks that were previously done by humans, providing motion in a safe, controlled manner. As defined in this book, actuator design is a subset of mechanical design. It involves engineering the mechanical components necessary to make a product move as desired. Fundamentals of Engineering High-Performance Actuator Systems, by Ken Hummel, was written as a text to supplement actuator design courses, and a reference to engineers involved in the design of high-performance actuator systems. It highlights the design approach and features what should be considered when moving a payload at precision levels and/or speeds that are not as important in low-performance applications.

The most recent goal of our research program was to identify the optimal features of each of three garments to maintain core temperature and comfort under intensive physical exertion. Four males and 2 females between the ages of 22 and 46 participated in this study. The garments evaluated were the MACS-Delphi, Russian Orlan, and NASA LCVG. Subjects were tested on different days in 2 different environmental chamber temperature/humidity conditions (24°C/H∼28%; 35°C/H∼20%). Each session consisted of stages of treadmill walking/running (250W to 700W at different stages) and rest. In general, the findings showed few consistent differences among the garments. The MACS-Delphi was better able to maintain subjects within a skin and core temperature comfort zone than was evident in the other garments as indicated by a lesser fluctuation in temperatures across physical exertion levels.

When technologies are traded for incorporation into vehicle systems to support a specific mission scenario, they are often assessed in terms of “Technology Readiness Level” (TRL). TRL is based on three major categories of Core Technology Components, Ancillary Hardware and System Maturity, and Control and Control Integration. This paper describes the Technology Readiness Level assessment of the Carbon Dioxide Reduction Assembly (CRA) for use on the International Space Station. A team comprising of the NASA Johnson Space Center, Marshall Space Flight Center, Southwest Research Institute and Hamilton Sundstrand Space Systems International have been working on various aspects of the CRA to bring its TRL from 4/5 up to 6. This paper describes the work currently being done in the three major categories. Specific details are given on technology development of the Core Technology Components including the reactor, phase separator and CO2 compressor.

Hypothermia is a well documented problem for surgical patients and is historically addressed by the use of a variety of warming aids and devices applied to the patient before, during, and after surgery. Their effectiveness is limited in many surgeries by practical constraints of surgical access, and hypothermia remains a significant concern. Increasing the temperature of the operating room has been proposed as an alternative solution. However, operating room temperatures must be cool enough to limit thermal stress on the surgical team despite the heat transport barriers imposed by protective sterile garments. Space technology in the form of the liquid cooling garment worn by EVA astronauts answers this need. Hamilton Sundstrand Space Systems International (HSSSI) has been working with Hartford Hospital to adapt liquid cooling garment technology for use by surgical teams in order to allow them to work comfortably in warmer operating room environments.

NASA has long recognized the advantages of providing improved information interfaces to EVA astronauts and has pursued this goal through a number of development programs over the past decade. None of these activities or parallel efforts in industry and academia has so far resulted in the development of an operational system to replace or augment the current extravehicular mobility unit (EMU) Display and Controls Module (DCM) display and cuff checklist. Recent advances in display, communications, and information processing technologies offer exciting new opportunities for EVA information interfaces that can better serve the needs of a variety of NASA missions. Hamilton Sundstrand Space Systems International (HSSSI) has been collaborating with Simon Fraser University and others on the NASA Haughton Mars Project and with researchers at the Massachusetts Institute of Technology (MIT), Boeing, and Symbol Technologies in investigating these possibilities.

The demands of future NASA exploration and scientific missions in space force the reevaluation of some of the basic assumptions and approaches that underlie current extravehicular activity (EVA) systems. Developing designs that can simultaneously achieve the advanced capabilities and the reductions in system mass and mission expendables targeted by NASA has proven to be a formidable challenge. The constraints of human needs, space environments, and current EVA system architectures demand technical capabilities beyond current expectations to achieve system goals. Under NASA Institute for Advanced Concepts (NIAC) sponsorship, Hamilton Sundstrand has been studying a new system paradigm to achieve the EVA system goals. The Chameleon Suit concept employs an active pressure suit that directly interacts between human systems and space environments.

The Conductivity Sensor designed for use in the Node 3 Water Processor Assembly (WPA) was based on the existing Space Shuttle application for the fuel cell water system. However, engineering analysis has determined that this sensor design is potentially sensitive to two- phase fluid flow (gas/liquid) in microgravity. The source for this sensitivity is the fact that free gas will become lodged between the sensor probe and the wall of the housing without the aid of buoyancy in 1-g. Once gas becomes lodged in the housing, the measured conductivity will be offset based on the volume of occluded gas. A development conductivity sensor was flown on the NASA Microgravity Plane (KC-135) to measure the offset, which was determined to range between 0 and 50%. This range approximates the offset experienced in 1-g gas sensitivity testing.

Enhancements to the Regenerable Carbon Dioxide Removal System (RCRS) have undergone full-scale, pre-prototype development and testing to demonstrate a redundant system within the volume allotted for the RCRS on the Space Shuttle Orbiter. The concept for a Redundant Regenerable Carbon Dioxide Removal System (RRCRS) utilizes the existing canister of the RCRS, but partitions it into two, independent, two-bed systems. This partitioning allows for two, fully capable RCRS units to be packaged within the original volume, thus reducing stowage volume and launch weight when compared to the flight RCRS plus the backup LiOH system. This paper presents the results of development and testing of a full-scale, pre-prototype RRCRS and includes an overview of the design concept for a redundant system that can be packaged within the existing envelope.

This paper describes the New Shuttle Orbiter's Multi-Purpose Logistics Module (MPLM) Cargo Heat Exchanger (HX) and associated MPLM cooling system. Heat Exchanger (HX) design and system performance characteristics of the system are presented.

This project is a Phase III SBIR contract between NASA and Water Reuse Technology (WRT). It covers the redesign, modification, and construction of the Wiped-Film Rotating-Disk (WFRD) evaporator for use in microgravity and its integration into a Vapor Phase Catalytic Ammonia Removal (VPCAR) system. VPCAR is a water processor technology for long duration space exploration applications. The system is designed as an engineering development unit specifically aimed at being integrated into NASA Johnson Space Center's Bioregenerative Planetary Life Support Test Complex (BIO-Plex). The WFRD evaporator and the compressor are being designed and built by WRT. The balance of the VPCAR system and the integrated package are being designed and built by Hamilton Sundstrand Space Systems International, Inc. (HSSSI) under a subcontract with WRT. This paper provides a description of the VPCAR technology and the advances that are being incorporated into the unit.

The International Space Station Waste Collector Subsystem Risk Mitigation Experiment (ISS WCS RME) was flown as the primary (Shuttle) WCS on Space Shuttle flight STS-104 (ISS-7A) in July 2001, to validate new design enhancements. In general, the WCS is utilized for collecting, storing, and compacting fecal & associated personal hygiene waste, in a zero gravity environment. In addition, the WCS collects and transfers urine to the Shuttle waste storage tank. All functions are executed while controlling odors and providing crew comfort. The ISS WCS previously flew on three Shuttle flights as the Extended Duration Orbiter (EDO) WCS, as it was originally designed to support extended duration Space Shuttle flights up to 30 days in length. Soon after its third flight, the Space Shuttle Program decided to no longer require 30 day extended mission duration capability and provided the EDO WCS to the ISS Program.

A Rotary Separator/Accumulator (RSA) has been developed to function as a phase separator and accumulator in the Oxygen Generator Assembly (OGA) in the microgravity environment of the International Space Station. The RSA design utilizes a fixed housing with rotating disks to create a centrifugal force field to separate hydrogen gas from water. The volume within the assembly is utilized to act as an accumulator for the OGA. During the development of the RSA, design refinements were made to meet the changing system operating requirements. Two proof of concept (POC) units and a “flight-like” development unit were fabricated and tested as system requirements evolved. Testing of the first POC unit demonstrated that a combined rotary separator and accumulator was feasible and showed areas where improvements could be made. The second POC unit incorporated a fifty percent volume increase to accommodate changing system requirements and geometry changes to help reduce power consumption.

Hamilton Sundstrand Space Systems International (HSSSI) has been conducting an internal research and development study of an integrated portable life support system design for advanced exploration missions. This design combines several new subsystem and component concepts to achieve dramatic reductions in system weight and consumables and increased reliability and safety. The study includes the design and manufacture of subsystems and components and the assembly and test of an integrated bench top system prototype. The system design and the results of testing and analysis are described.

A Low Pressure Electrolyzer (LPE) is being developed to provide metabolic oxygen aboard US nuclear submarines. The system is derived from a more complex system already developed for the Virginia Class of attack submarines. The LPE generates up to 250 standard cubic feet per hour (SCFH) of oxygen at ambient pressure through electrolysis of water utilizing SPE® (Solid Polymer Electrolyte) technology. The hydrogen is generated at pressures suitable for disposal overboard. The system operates unattended which minimizes crew workload, and can safely shut down without crew intervention. Generating oxygen at ambient pressure significantly reduces risk to personnel and greatly simplifies the system. Reliability, maintainability, safety, and ease of operation are major system design drivers.

Designing an EVA system for Mars’s exploration will require a thorough understanding of the mission. Data are available from NASA mission studies, preliminary EVA requirements document, and Apollo program experience. However, additional relevant field experience is required to complete the picture. NASA has addressed this through field tests using prototype EVA equipment and field science programs like the Haughton Mars Project on Devon Island. There, a group of scientists conducts scientific exploration in and around an impact crater in a polar desert similar to expected exploration sites on Mars. Hamilton Sundstrand Space Systems Intl. (HSSSI) EVA system engineers participated in the summer 2000 field research program to gain firsthand knowledge of field science activities. By using a Mars EVA system mockup, they were also able to conduct experiments on EVA system impacts on field science tasks. This field experience and some of its results are described in this paper.

Psychological, group interaction, and task performance characteristics were evaluated in four polar expedition teams varying in national and gender composition. Leaders played a crucial role in promoting strong group cohesiveness and morale. North American members were more highly focused on achievement strivings, Russians on avoidance of failure. Gender differences in behavior were also evident. An all women's team demonstrated a high level of cooperativeness and social support of other team members. Across teams, anxiety, tension, and health concerns increased in the early stages of the expedition and decreased significantly at later stages. The overall findings indicate the need to focus on the interaction of personality, cultural, gender, and task performance demands in personnel selection and during long duration missions. Implications for the optimal design of space vehicles and habitats are discussed.

In support of the Department of Defense goal to streamline procurements, the Army recently decided to discontinue use of VV-F-800D as the purchase specification for diesel fuel being supplied to continental United States military installations. The Army will instead issue a commercial item description for direct fuel deliveries under the Post-Camp-Station (PCS) contract bulletin program. In parallel, the Defense Fuel Supply Center and the U.S. Army Mobility Technology Center-Belvoir (at Ft. Belvoir, VA) initiated a fuel survey with the primary objective to assess the general quality and lubricity characteristics of low sulfur diesel fuels being supplied to military installations under the PCS system. Under this project, diesel fuel delivery samples were obtained from selected military installations and analyzed according to a predetermined protocol.

A technology demonstration program was conducted by the U.S. Army to verify the feasibility of using aviation turbine fuel JP-8 in all military diesel fuel-consuming ground vehicles and equipment (V/E). Over 2,800 pieces of military equipment participated in a two and one-half year program accumulating over 2,621,000 total miles (4,219,810 km) using JP-8 in combat/tracked, tactical/wheeled, and transportation motor pool vehicles. Over 71,000 hours of operation were accumulated in diesel/turbine engine-driven generator sets using JP-8 fuel. Comparisons of various performance areas with baseline diesel fuel (DF-2) operation were made.