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Piezoelectric pumps offer great potential as an alternative electro-mechanical actuator and as a hydraulic power source. As an actuator, this pump may provide solutions to control system problems in robotics, process control, bioengineering, advanced remote control (telepresence), and automation. As a hydraulic power source they may be useful for active thermal cooling, fluid management, and metering pumps in life support applications. The benefits of piezoelectric based pumps and actuators include increased efficiency, self-cooling, lightweight, compact size, high mechanical reliability, positive displacement, self-priming, no lubrication, no vibration, and rotational inertia. Oceaneering Space Systems (OSS) has produced two successful piezoelectric pump prototypes. The first one is a double-acting diaphragm pump driven by piezoelectric PolyVinylidine DiFluoride (PVDF) polymer. The second prototype is a Lead Zirconate Titanate (PZT) thermoplastic laminated pump.

The Trace Gas Analyzer (TGA, Figure 1) is a self-contained, battery-powered mass spectrometer that is designed for use by astronauts during extravehicular activities (EVA) on the International Space Station (ISS). The TGA contains a miniature quadrupole mass spectrometer array (QMSA) that determines the partial pressures of ammonia, hydrazines, nitrogen, and oxygen. The QMSA ionizes the ambient gas mixture and analyzes the component species according to their charge-to-mass ratio. The QMSA and its electronics were designed, developed, and tested by the Jet Propulsion Laboratory (1,2). Oceaneering Space Systems supported JPL in QMSA detector development by performing 3D computer for optimal volumetric integration, and by performing stress and thermal analyses to parameterize environmental performance.

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.

Progress on the delivery of the Vehicle Cabin Atmosphere Monitor (VCAM) is reported. VCAM is an autonomous trace-species detector to be used aboard the International Space Station (ISS) for atmospheric analysis. The instrument is based on a low-mass, low-power miniature preconcentrator, gas chromatograph, and Paul ion trap mass spectrometer (PCGC/MS) capable of measuring volatile constituents in a space vehicle or planetary outpost at sub-ppm levels. VCAM detects and quantifies 40 target compounds at their 180-day Spacecraft Maximum Allowable Concentration (SMAC) levels. It is designed to operate autonomously, maintenance-free, with a self-contained carrier and calibration gas supplies sufficient for a one-year lifetime. Two flight units will be delivered for operation in the ISS EXPRESS rack.

Procedures for rapid microbiological analysis were performed during simulated surface extra-vehicular activity (EVA) at Meteor Crater, Arizona. The fully suited operator swabbed rock (‘unknown’ sample), spacesuit glove (contamination control) and air (negative control). Each swab sample was analyzed for lipopolysaccharide (LPS) and β-1, 3-glucan within 10 minutes by the handheld LOCAD PTS instrument, scheduled for flight to ISS on space shuttle STS-116. This simulated a rapid and preliminary ‘life detection’ test (with contamination control) that a human could perform on Mars. Eight techniques were also evaluated for their ability to clean and remove LPS and β-1, 3-glucan from five surface materials of the EVA Mobility Unit (EMU). While chemical/mechanical techniques were effective at cleaning smooth surfaces (e.g. RTV silicon), they were less so with porous fabrics (e.g. TMG gauntlet).

Work is underway to deliver an instrument for analysis of the atmosphere aboard the International Space Station. The Vehicle Cabin Atmosphere Monitor (VCAM) is based on a low-mass, low-power miniature preconcentrator gas chromatograph/mass spectrometer (PCGC/MS) capable of providing sub-ppm measurements of volatile constituents in a space vehicle or outpost. VCAM is designed to operate autonomously, maintenance-free, once per day, with its own carrier and calibration gas supplies sufficient for a one-year lifetime. VCAM performance is sufficient to detect and identify 90% of the target compounds specified at their 180-day Spacecraft Maximum Allowable Concentration (SMAC) levels. The flight units will be delivered in mid-2008 and be operated in the ISS EXPRESS rack.

This paper describes the effort performed by Oceaneering Space Systems, Air-Lock, Inc., Raven Aerospace Technology, Inc., and David Clark Company, Inc. to develop lightweight and low-profile spacesuit bearings. Current spacesuit bearings constitute a significant portion of the spacesuit mass and reducing this weight will improve extravehicular activity (EVA) capabilities and reduce launch mass. Reducing the profile of the bearings will increase crew comfort in the suit on long duration missions. The recommended concepts for the waist, scye (shoulder), arm, and wrist bearings share the same basic configuration to achieve weight reduction and a low profile with little technical risk. The bulk structural material is a lightweight carbon/epoxy composite. The bearing race material is 440C stainless steel for wear resistance and hardness. Many features of existing spacesuit bearings were retained to minimize technical risk.

For NASA's Constellation Program, an Intravehicular Activity (IVA) and Extravehicular Activity (EVA) Life Support Umbilical System (LSUS) will be required to provide environmental protection to the suited crew during Crew Exploration Vehicle (CEV) cabin contamination or depressurization and contingency EVAs. The LSUS will provide the crewmember with ventilation, cooling, power, communication, and data, and will also serve as a crew safety restraint during contingency EVAs. The LSUS will interface with the Vehicle Interface Assembly (VIA) in the CEV and the Suit Connector on the suit. This paper describes the effort performed to develop concept designs for IVA and EVA umbilicals, universal multiple connectors, handling aids and stowage systems, and VIAs that meet NASA's mission needs while adhering to the important guiding principles of simplicity, reliability, and operability.

Similar to finding a home on Earth, location is important when selecting where to set up an exploration outpost. Essential considerations for comparing potential lunar outpost locations include: (1) areas nearby that would be useful for In-Situ Resource Utilization (ISRU) oxygen extraction from regolith for crew breathing oxygen as well as other potential uses; (2) proximity to a suitable landing site; (3) availability of sunlight; (4) capability for line-of-sight communications with Earth; (5) proximity to permanently-shadowed areas for potential in-situ water ice; and (6) scientific interest. The Mons Malapert1 (Malapert Mountain) area (85.5°S, 0°E) has been compared to these criteria, and appears to be a suitable location for a lunar outpost.

Oceaneering International has developed and implemented a real-time system to augment the situational awareness of subsea Remotely Operated Vehicle (ROV) operators. This system, called Modular Integrated Man-Machine Interaction Control (MIMIC), provides the operator with vehicle state information and augments the ROV camera views with additional simulated views of the worksite and the ROV. It creates the simulated views using CAD models of the ROV and the operational environment integrated with real-time vehicle sensor feedback and physics-based dynamic simulations. This capability is the most significant situational awareness system development since the advent of sonar for underwater remotely operated vehicles tasked with exploration and development of deep ocean resources.

The Sublimator Driven Coldplate is a unique piece of thermal control hardware that has several advantages over a traditional thermal control scheme. The principal advantage is the possible elimination of a pumped fluid loop, potentially saving mass, power, and complexity. Because this concept relies on evaporative heat rejection techniques, it is primarily useful for short mission durations. Additionally, the concept requires a conductive path between the heat-generating component and the heat rejection device. Therefore, it is mostly a relevant solution for a vehicle with a relatively low heat rejection requirement. This paper describes the design of an engineering development unit intended to demonstrate the feasibility of the Sublimator Driven Coldplate concept.

Storing breathing gas as a cryogenic liquid rather than a compressed gas has advantages in profile, weight, and safety. The disadvantage of the extremely cold temperature can be turned into an advantage by cooling the user while vaporizing and warming the cryogen. A cryogenic breathing apparatus capable of providing up to two hours of breathing and cooling and operating in any orientation will be available to commercial users in 1998. The same technology can be easily extended to use with liquid oxygen on the moon and Mars, and can be adapted to a zero gravity environment.

Carbon dioxide (CO2) removal technology development for portable life support systems (PLSS) has traditionally concentrated in the areas of solid and liquid chemical sorbents and semi-permeable membranes. Most of these systems are too heavy in gravity environments, require prohibitive amounts of consumables for operation on long term planetary missions, or are inoperable on the surface of Mars due to the presence of a CO2 atmosphere. This paper describes the effort performed to mature an innovative CO2 removal technology that meets NASA's planetary mission needs while adhering to the important guiding principles of simplicity, reliability, and operability. A breadboard cryogenic carbon dioxide scrubber for an ejector-based cryogenic PLSS was developed, designed, and tested. The scrubber freezes CO2 and other trace contaminants out of expired ventilation loop gas using cooling available from a liquid oxygen (LOX) based PLSS.

This paper summarizes the results of two studies performed in 1995 [1] and 1996 [2] which lay out the case for commercializing services performed in space by Extra Vehicular Activity (EVA). EVA services include all work done external to pressurized volumes, whether directly by humans or remotely by machines. The studies draw heavily on the experience of the subsea service industry because the environments, work, and equipment have many, relevant similarities. It examines several historical parallels which serve as models of how a government activity has been successfully commercialized, examines the markets and cost structure of EVA operations to verify the potential profitability of such an endeavor, and lays out a plan for the transition to commercial services.