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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.

Catalytic oxidation is an effective means of controlling the build up of ammonia and other trace gas contaminants within closed spaces. However, it sometimes leads to the formation of noxious gases that need to be removed in post-treatment systems. In addition, ammonia removal is an issue when regeneration of water from wastewater is considered since ammonia is a byproduct of urea decomposition. For example, the VPCAR (Vapor Phase Catalytic Ammonia Reduction) advanced water processor system includes an oxidation reactor for the destruction of ammonia and of other volatile organics that are not separated out in the evaporator due to their volatility. The oxidation of ammonia may produce nitrogen, nitrogen oxides (NO and NO2), nitrous oxide (N2O) and water vapor. The Spacecraft Maximum Allowable Concentration (SMAC) for NO and NO2 are respectively 4.5 and 0.5 ppm whereas the Threshold Limit Value (TLV) for N2O is 25 ppm.

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.

Hamilton Sundstrand Space Systems International (HSSSI) is currently under contract with NASA MSFC to design, fabricate and deliver the Water Processor Assembly (WPA) for the International Space Station (ISS). As part of this effort HSSSI has developed an oxidation catalyst for the catalytic reactor assembly in the WPA. This paper discusses full-scale development reactor testing and the status of the life testing of the oxidation catalyst used in the reactor.

Pyrolysis processing is one of several options for solid waste resource recovery in space. It has the advantage of being relatively simple and adaptable to a wide variety of feedstocks and it can produce several usable products from typical waste streams. The overall objective of this study was to produce a prototype mixed solid waste pyrolyzer for spacecraft applications. A two-stage reactor system was developed which can process a maximum of about 0.5 kg of waste per cycle. The reactor includes a pyrolysis chamber where the waste is heated to temperatures above 600 °C for primary pyrolysis. The volatile products (liquids, gases) are transported by a N2 purge gas to a second chamber which contains a catalyst bed for cracking the tars at temperatures of about 1000-1100 °C. The tars are cracked into carbon and additional gases. Most of the deposited carbon is subsequently gasified by oxygenated volatiles (CO2, H2O) from the first stage.

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.

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.