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This paper will review the design approach and hardware involved with the long-term telerobotic support of a deepwater subsea completion complex. The key to a successful design involves matching the design of the subsea equipment and interfaces with the capabilities of the telerobot support system while simultaneously maximizing simplicity, maintainability, reliability and expandability.

This paper describes the operational principles of a hybrid capillary pumped loop in general, and results on testing of a high power hybrid system in particular. A hybrid capillary pumped loop is a thermal control system which consists of a capillary pumped loop and a mechanical pump which is placed in series with the capillary evaporators in the liquid return line. The hybrid loop can be operated in either a passive capillary mode, or in a pump-assisted mode, whereby the mechanical pump augments the heat transport capability of the capillary evaporators. The high power hybrid system was built to demonstrate the feasibility of such a hybrid loop concept. Test results verified that a hybrid loop could be operated in either mode, and that transition between these two modes of operation required opening or closing a single valve on the liquid line.

There is a great need for reliable environmental sensors that can monitor the concentrations of gases and vapors such as oxygen, carbon dioxide, carbon monoxide, water vapor and other contaminants of the cabin air in a manned space station. Honeywell has developed a new class of electrochemical gas sensors based on nonaqueous electrolytes. Sensors with three electrode configuration and gold sensing electrodes have been fabricated and used for monitoring both carbon dioxide and oxygen with the capability to monitor water vapor using linear scanning voltammetry. Sensors with platinum sensing electrodes have been used to monitor low concentrations of toxic gases such as carbon monoxide and nitrogen oxides with potential capability to monitor organic contaminants. Experimental results obtained with these low-power and microprocessor-based sensors will be presented.

High-power heat transport systems for large space platforms such as Space Station require the use of complex fluid loops to effectively and efficiently move waste heat energy from source to sink. In particular, use of two-phase heat acquisition and transport systems offers significant advantages such as reduction of pump power, automation of control systems, constant sink temperatures at the load, and flexible load placement. Analytical tools are needed for design analysis and performance prediction of these systems. Moreover, environmental considerations and insulation systems need to be taken into account, especially when subcooling and superheating become important parameters in the overall design. This paper will discuss the development and use of FLOSIN, a system-level, two-phase fluid loop analyzer. It will explain the modeling approach for systems utilizing a Rotary Fluid Management Device (RFMD), Back Pressure Regulating Valve (BPRV), and cavitating Venturis.

Space Station water recovery involves five separate reprocessing loops: potable water from cabin humidity condensate and carbon dioxide reduction water, hygiene water from crew hygiene activities, hygiene water from crew urine, animal cage wash water and experiment waste water. The magnitudes of the separation tasks involved differ substantially, as do the waste and product water qualities. Three different phase change water recovery technologies are being considered for Space Station use. They include Air Evaporation, Thermoelectric Integrated Membrane Evaporation and Vapor Compression Distillation (VCD). The potential application of these technologies to each reprocessing loop is considered. Comparisons are drawn for urine processing based on a range of evaluation criteria, including product water quality, specific energy, percent recovery, power, weight, resupply needs, reliability, technological maturity, zero-gravity compatibility and contamination potential.

In an effort to reduce the weight of medical supplies that must be sent into space to support the Health Maintenance Facility (HMF) of the Space Station, a disposable cartridge (SWIS) is being developed which will purify the Space Station potable water to USP XXI(1) Water for Injection (WFI) quality. This water will subsequently be mixed with concentrates to reconstitute intravenous solutions such as Ringer's Lactate, which would be used in emergency situations for treatment of ill or injured crew members. The SWIS purification process train will consist of particulate prefiltration, carbon adsorption, mixed bed deionization, ultrafiltration, and sterilizing microfiltration. The present concept envisions a device that will be passive in nature, requiring only tap pressure as the driving force for filtration. The SWIS is being designed to produce at least 6 liters of WFI at a flow rate of 6 liters/hour.

Thermal management systems are currently being developed for application on large orbiting platforms, specifically the Space Station. Based upon its thermodynamic properties, ammonia was selected as a working fluid suitable to handle the power and heat rejection requirements of these systems. The Space Station's 30-year design life, minimum maintenance requirement, maximum reliability, and ammonia working fluid have led to new material compatibility issues. Although ammonia is a well understood fluid for ground-based refrigeration uses, it produced some unexpected results when applied to space-based heat transport systems.

Preprotype air revitalization and water reclamation subsystems (Mole Sieve, Sabatier. Static Feed Electrolyzer, Trace Contaminant Control, and Thermoelectric Integrated Membrane Evaporative Subsystem) were operated and tested independently and in an integrated arrangement. During each test, water and/or gas samples were taken from each subsystem so that overall subsystem performance could be determined. The overall test design and objectives for both subsystem and integrated subsystem tests were limited, and no effort was made to meet water or gas specifications. The results of chemical analyses for each of the participating subsystems are presented along with other selected samples which were analyzed for physical properties and microbiologicals.

An experiment was performed to observe flow regimes and measure pressure drops of two-phase (liquid/vapor) flow and condensation in reduced gravity. Testing was conducted aboard the NASA-JSC KC-135 reduced gravity aircraft using a prototype two-phase thermal management system for large spacecraft. A clear section of two-phase line enabled visual and photographic observation of the flow regimes. The two-phase mixture was generated by pumping nearly saturated liquid refrigerant 114 through an evaporator and adding heat through electric heaters. The resultant two-phase flow was varied by changing the evaporator heat load, creating qualities from 0.05 to 0.80. Visual and photographic observation of vapor condensation was also made through a clear cover on the system condenser. During the flight tests, the experiment hardware was exposed to gravitational acceleration ranging from near-zero to 1.8 g's.

Two-phase flow technology has the potential to significantly improve spacecraft heat acquisition, transport, and control. Using the latent heat of fluids, ammonia in particular, orders of magnitude more heat can be transferred than is possible using the sensible heat of single-phase fluids. During the past several years, two-phase heat transport systems, in which surface-tension forces established in a fine-pore capillary wick circulate the working fluid, have demonstrated performance potentials compatible with future Space Station and advanced space-based program requirements. This paper presents details of the design, analysis, fabrication, and test plan of a CPL flight experiment program. Results of this program will be important in the overall qualification of this technology for use on such advanced programs as Space Station and beyond.

The HERMES Thermal Control System necessitates the adoption of both Active and Passive Thermal Control techniques. The ATCS (Active Thermal Control Section) utilizes fluid coolant loops collecting and transporting heat loads from the various sources to the available sink devices. The methods of analysis and trade-off applied in the preliminary phase of the design activities are described, with particular attention to the selection of the fluid, the architecture of the loop, the flow sequence of the equipment in line and the redundancy policy. The design driving criteria are then discussed, outlining the optimization efforts concerning the aspects of mass saving and safety. For the PTCS (Passive Thermal Control Section), the design philosophy together with analysis approach and techniques are described.

The Space Station (SS) presents a plethora of human factors engineering opportunities. In particular, design for the space suited (extravehicular mobility unit) EVA crewperson is critical from several aspects, e.g., safety, ease of task conduct, timeline reductions, risk elimination, productivity enhancement, etc. This paper will address the human factors engineering effort undertaken to aid in the early-on design of the Space Station structure, with particular emphasis on structural assembly operations.

The HERMES Spaceplane is being designed and developed by AEROSPATIALE for the European Space Agency (ESA). The Spaceplane is designed to transport three people and three metric tons of payload to a Space Station. This paper describes the thermal control system for the HERMES Spaceplane. It is comprised of the outer thermal protection system, the internal passive thermal control system and an internal active thermal conditioning device, including and Environmental Control and life Support system (ECLS) and an Active Thermal Control System (ATCS). Different mission conditions including reentry, in-orbit and launch phases are described.

NASA-STD-3000, Man-Systems Integration Standards (MSIS), is the first NASA and industry-wide design specification for living and working in space. The EVA section of MSIS affects all future EVA systems and operations. This paper presents an overview of this far-reaching new standard with particular focus on its implications for EVA and human engineering. The MSIS provides the specific information needed to ensure proper integration of man-system interface requirements with those of other aerospace disciplines. These man-system interface requirements apply to the launch, entry, on-orbit, and extraterrestrial space environments. The MSIS is intended for use by design engineers, operations analysts, human factors specialists, and others engaged in the definition and development of manned space programs. In addition to requirements, the MSIS provides design considerations and examples for the various topics, including EVA.

Recently, interest has developed for a process to reclaim waste water from experiments in the Space Station United States Laboratory (USL). The need for a water recovery system has been generated from a growing list of experiments proposed for the Space Station that will require ultrapure water. These proposed experiments will require water that meets both USP XXI and the ASTM proposed Electronics Grade Specifications. This high quality water may be produced by a hybrid of new technologies and by water subsystems currently considered for Environmental Control and Life Support on the Space Station. To evaluate these water recovery systems and other technologies, a testing program was conducted to challenge individual water recovery subsystems with waste solutions from experiments typical of those that will be a part of the USL. The water recovery systems are being evaluated based on the permeate water quality.

A new system has been designed to simulate orbital-extravehicular (EVA) work to provide for real-time measurement of physiological parameters. Such a system described here incorporates an experimental protocol, exercising subject, controlled-atmosphere chamber, EVA-work simulation exercise device, medical instrumentation and a data acquisition system. Applications of the neutral-buoyancy method and other laboratory-simulation methods are described. This information is presented to facilitate the understanding of this exercise device as a possible additional orbital-EVA work-simulation tool. Important engineering issues associated with the design of the proposed system are discussed.

With the coming of the U.S. Space Station, the testing of the water reclamation system in zero-g could become very important to avoid costly redesigns and logistic problems. There are currently no plans to test the hardware in zero-g for long durations. This paper outlines one possible way to test the potable water reclamation system as a spacelab payload and the hygiene water reclamation system as a middeck payload in zero-g, while using existing National Space Transportation System (NSTS) flight hardware.

New components have been developed for an active thermal control system, to meet the extreme thermal requirements of the SPACELAB fluid science “Critical Point Facility”. A water cold plate with a double spiral fluid channel acts as a variable conductance heat sink for the high precision thermostat. This channel geometry achieves high heat flux densities on its planar isothermal contact surface. A thermostat unit consisting of two thermo-electrical Peltier element heat pumps and one electrical heater regulates the upstream temperature inside an air cooled electronic box. Both of these elements are pulse-width operated, to compensate the environmental temperature fluctuations.

The range of motion of space suits has traditionally been described using limited two-dimensional mapping of limb, torso, or arm movements performed in front of an orthogonal grid. This paper describes an improved technique for recovering range of motion data, and a validation of the technique performed on an Extravehicular activity space suit. The new technique uses digitized data which is automatically acquired from video images of the subject. Three-dimensional trajectories are recovered from these data, and can be displayed using three-dimensional computer graphics. Target locations are recovered using a unique video processor and close range photogrammetry. Such data can be used in a wide variety of applications, including the animation of anthropometric computer models. The applications and limitations of the new technique are discussed.

Contaminant monitoring and control is vital in maintaining a habitable atmosphere in an enclosed environment. Substances which impair normal human psychophysiological functions are constantly being produced. This requires both contaminant monitoring and removal equipment. In addition to actively removing contaminants, a passive control program can limit the types of undesirable materials allowed inside the environment. This paper will discuss potential sources of airborne contaminants, how they are monitored, and passive and active methods of contaminant control. The paper will also discuss some of the system design constraints and parameters involved in both an undersea submersible vehicle and a space based facility.