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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 91 records · Page 5

Movable Cameras And Monitors For Viewing Telemanipulator

Three methods proposed to assist operator viewing telemanipulator on video monitor in control station when video image generated by movable video camera in remote workspace of telemanipulator. Monitors rotated or shifted and/or images in them transformed to adjust coordinate systems of scenes visible to operator according to motions of cameras and/or operator's preferences. Reduces operator's workload and probability of error by obviating need for mental transformations of coordinates during operation. Methods applied in outer space, undersea, in nuclear industry, in surgery, in entertainment, and in manufacturing.

Diner, Daniel B.↗

Micro-video display with ocular tracking and interactive voice control

In certain space-restricted environments, many of the benefits resulting from computer technology have been foregone because of the size, weight, inconvenience, and lack of mobility associated with existing computer interface devices. Accordingly, an effort to develop a highly miniaturized and 'wearable' computer display and control interface device, referred to as the Sensory Integrated Data Interface (SIDI), is underway. The system incorporates a micro-video display that provides data display and ocular tracking on a lightweight headset. Software commands are implemented by conjunctive eye movement and voice commands of the operator. In this initial prototyping effort, various 'off-the-shelf' components have been integrated into a desktop computer and with a customized menu-tree software application to demonstrate feasibility and conceptual capabilities. When fully developed as a customized system, the interface device will allow mobile, 'hand-free' operation of portable computer equipment. It will thus allow integration of information technology applications into those restrictive environments, both military and industrial, that have not yet taken advantage of the computer revolution. This effort is Phase 1 of Small Business Innovative Research (SBIR) Topic number N90-331 sponsored by the Naval Undersea Warfare Center Division, Newport. The prime contractor is Foster-Miller, Inc. of Waltham, MA.

Miller, James E.↗

A prototype case-based reasoning human assistant for space crew assessment and mission management

We present a prototype human assistant system for space crew assessment and mission management. Our system is based on case episodes from American and Russian space missions and analog environments such as polar stations and undersea habitats. The general domain of small groups in isolated and confined environments represents a near ideal application area for case-based reasoning (CBR) - there are few reliable rules to follow, and most domain knowledge is in the form of cases. We define the problem domain and outline a unique knowledge representation system driven by conflict and communication triggers. The prototype system is able to represent, index, and retrieve case studies of human performance. We index by social, behavioral, and environmental factors. We present the problem domain, our current implementation, our research approach for an operational system, and prototype performance and results.

Owen, Robert B.↗

Engineering development program of a closed aluminum-oxygen semi-cell system for an unmanned underwater vehicle: An update

Most emerging unmanned undersea vehicle (UUV) missions require significantly longer range and endurance than is achievable with existing battery technology. The Aluminum-Oxygen (Al-O2) semi-cell is a candidate technology capable of providing a significant improvement in endurance compared to the silver-zinc battery technology currently used in UUVs and compares favorably to other proposed UUV power systems not only in performance, but also in safety and logistics. An Al-O2 semi-cell system is under development by Loral Defense Systems-Akron (Loral) for the ARPA/Navy 44 in. diameter UUV test vehicle. The power plant consists of a cell stack, gas management, oxygen storage, electrolyte management, coolant and controller subsystems, designed to replace the existing silver-zinc battery and meet existing weight, volume, electrical and thermal requirements, therefore minimizing modifications to the UUV. A detailed system design is complete. A component and material endurance test to evaluate compatibility and reliability of various material arid components is complete. Sub scale (Short stack) system testing is completed. A full-scale demonstration unit is now under construction in the second half of 1995. The full scale demonstration test will simulate environmental conditions of the operational system. This paper summarizes the results of the extensive short stack and endurance test programs, describes the plan for full-scale testing, and concludes with a brief discussions of future directions for this technology. This program is sponsored by ARPA Maritime Systems Technology Office under NASA contract NAS3-26715.

Gregg, Dane W.↗

Shielded, Automated Umbilical Mechanism

Umbilical mechanism automatically connects and disconnects various fluid couplings and/or electrical contacts while shielding mating parts from debris. Reacts mating and demating loads internally, without additional supporting structures. All functions - extension of plug, mating, and movement of debris shields - actuated by single motor. If mechanism jams or fails at any point in sequence, override feature in drive train allows manual operation. Designed for service in outer space, where its shields protect against micrometeoroids, debris, ultraviolet radiation, and atomic oxygen. Used on Earth to connect or disconnect fluid or electrical utilities in harsh environments like those of nuclear powerplants or undersea construction sites, or in presence of radioactive, chemical, or biological hazards, for example.

Barron, Daniel R.↗

Dual use display systems for telerobotics

This paper describes a telerobotics display system, the Multi-mode Manipulator Display System (MMDS), that has applications for a variety of remotely controlled tasks. Designed primarily to assist astronauts with the control of space robotics systems, the MMDS has applications for ground control of space robotics as well as for toxic waste cleanup, undersea, remotely operated vehicles, and other environments which require remote operations. The MMDS has three modes: (1) Manipulator Position Display (MPD) mode, (2) Joint Angle Display (JAD) mode, and (3) Sensory Substitution (SS) mode. These three modes are discussed in the paper.

Massimino, Michael J.↗

Umbilical mechanism assembly for the international space station

Mechanisms for engaging and disengaging electrical and fluid line connectors are required to be operated repeatedly in hazardous or remote locations on space station, nuclear reactors, toxic chemical and undersea environments. Such mechanisms may require shields to protect the mating faces of the connectors when connectors are not engaged and move these shields out of the way during connector engagement. It is desirable to provide a force-transmitting structure to react the force required to engage or disengage the connectors. It is also desirable that the mechanism for moving the connectors and shields is reliable, simple, and the structure as lightweight as possible. With these basic requirements, an Umbilical Mechanism Assembly (UMA) was originally designed for the Space Station Freedom and now being utilized for the International Space Station.

Mandvi, A. Ali↗

GPS Moving Vehicle Experiment

The Naval Research Laboratory (NRL) in the development of timing systems for remote locations, had a technical requirement for a Y code (SA/AS) Global Positioning System (GPS) precise time transfer receiver (TTR) which could be used both in a stationary mode or mobile mode. A contract was awarded to the Stanford Telecommunication Corporation (STEL) to build such a device. The Eastern Range (ER) als had a requirement for such a receiver and entered into the contract with NRL for the procurement of additional receivers. The Moving Vehicle Experiment (MVE) described in this paper is the first in situ test of the STEL Model 5401C Time Transfer System in both stationary and mobile operations. The primary objective of the MVE was to test the timing accuracy of the newly developed GPS TTR aboard a moving vessel. To accomplish this objective, a joint experiment was performed with personnel from NRL and the er at the Atlantic Undersea Test and Evaluation Center (AUTEC) test range at Andros Island. Results and discussion of the test are presented in this paper.

Oaks, O. J.↗

Engineering Development Program of a Closed Aluminum-Oxygen Semi-cell System for an Unmanned Underwater Vehicle: An Update

Most emerging unmanned undersea vehicle (UUV) missions require significantly longer range and endurance than is achievable with existing battery technology. The Aluminum-Oxygen (Al-O2) semi-cell is a candidate technology capable of providing a significant improvement in endurance compared to the silver-zinc battery technology currently in use in UUVs and compares favorably to other proposed UUV power systems not only in performance, but also in safety and logistics. An Al-O2 semi-cell system is under development, consisting of a cell stack, gas management, oxygen storage, electrolyte management coolant and controller subsystems. It is designed to replace the existing silver-zinc battery and meet existing weight, volume, electrical and thermal requirements, therefore minimizing modification to the UUV. A detailed system design is complete. A component and material endurance test to evaluate compatibility and reliability of various materials and components is complete. Sub=scale (short stack) system testing is complete. A full-scale demonstration unit is now under construction for testing in the second half of 1995. The full scale demonstration test will simulate environmental conditions of the operational system. This paper summarizes the results of the extensive short stack and endurance test programs, describes the plan for full-scale testing, and concludes with a brief discussion of future directions for this technology.

Gregg, Dane W.↗

Studies of the Interactions Between Vestibular Function and Tactual Orientation Display Systems

When humans experience conditions in which internal vestibular cues to movement or spatial location are challenged or contradicted by external visual information, the result can be spatial disorientation, often leading to motion sickness. Spatial disorientation can occur in any situation in which the individual is passively moved in the environment, but is most common in automotive, aircraft, or undersea travel. Significantly, the incidence of motion sickness in space travel is great: The majority of individuals in Shuttle operations suffer from the syndrome. Even after the space-sickness-producing influences of spatial disorientation dissipate, usually within several days, there are other situations in which, because of the absence of reliable or familiar vestibular cues, individuals in space still experience disorientation, resulting in a reliance on the already preoccupied sense of vision. One possible technique to minimize the deleterious effects of spatial disorientation might be to present attitude information (including orientation, direction, and motion) through another less-used sensory modality - the sense of touch. Data from experiences with deaf and blind persons indicate that this channel can provide useful communication and mobility information on a real-time basis. More recently, technologies have developed to present effective attitude information to pilots in situations in which dangerously ambiguous and conflicting visual and vestibular sensations occur. This summers project at NASA-Johnson Space Center will evaluate the influence of motion-based spatial disorientation on the perception of tactual stimuli representing veridical position and orientation information, presented by new dynamic vibrotactile array display technologies. In addition, the possibility will be explored that tactile presentations of motion and direction from this alternative modality might be useful in mitigating or alleviating spatial disorientation produced by multi-axis rotatory systems, monitored by physiological recording techniques developed at JSC.

Cholewiak, Roger W.↗

Numerical Simulation of a Chemically Reacting Sorbent Bed for LSS Applications

A detailed numerical model of a chemisorption bed has been developed. The model is based on the constant pressure mass transport equation for gaseous flow through a packed bed, and the equation for diffusion and reaction within a spherical particle. Because there is a wealth of data from the NASA and the Navy bodies of literature, the LiOH-H2O-CO2 system is chosen for application of the model and interpretation of results. Prior models of this system from the life support literature are limited. The current model incorporates many of the features of elaborate models developed for investigation of industrial systems or energy applications (e.g., coal, desulphurization): it distinguishes bulk convection and bed dispersion; mass transport to the particle surface, transport within the particle, and reaction. It uses the nonsteady (not pseudo-steady state) form of the equations. The chemistry is modeled as a multi-step, reversible reaction with evolving solid structure. The resulting system of equations is large. The ODEPACK family of solvers is used to integrate the system. Reaction coefficients are determined by experiment. Typical results of the model are illustrated with mission input parameters. Using the model, an explanation is offered for 1) the varied performance results found after pre-breathing (or after simulated pre-breathe conditions), 2) interrupted use and 3) low temperature use. In addition, options for a reusable canister are explored. The computational resource implications of adding energy equations are discussed briefly, as are applicability to other relevant space and undersea systems.

Luna, Bernadette↗

High-Resolution Electrospray Ionization/Ion Mobility Spectrometer for Detection of Abiotic Amino Acids

One of the primary goals of the current NASA thrust in Astrobiology is the detection and identification of organic molecules as part of an in-situ lander platform on the surface of Mars or Europa. The identification of these molecules should help determine whether indigenous organisms exist on the surface of Mars or in an undersea environment on Europa. In addition, a detailed organic chemical inventory of surface and near surface molecules will help elucidate the possibilities of life elsewhere in the Universe. Terrestrial life has, as its backbone, the family of molecules known as the amino acids (AA), and while AA can be found in the terrestrial environments as part of more complex molecules, such as peptides, and proteins, they also exist as individual molecules due to of the hydrolyses of biopolymers. In terrestrial biochemistry, there are 20 principal amino acids which are necessary for life. However, some forms of these molecules can be found in nature synthesized via abiotic process. For example, they are known to exist extraterrestrially as a component of carbonaceous meteorites. The idea that amino acids are readily created by abiotic means has been demonstrated by their positive identification in the Murchison CM2 meteorite, which fell in 1969. This meteorite was analyzed before contamination by terrestrial microbes could result. Three laboratories individually tested parts of the meteorite and concluded that the amino acids present in them were indigenous to the meteorite because, among other reasons, they had equal L- and D- enantiomers. Final identification of the constituents of the Murchison included 33 amino acids which have no known biotic source, 11 amino acids which have limited distribution and 8 (Glycine, Alanine, Valine, Proline, Leucine, Isoleucine, Aspartic Acid, and Glutamic Acid), which readily occur in terrestrial proteins.

L W Beegle↗

Innovative Robot Archetypes for In-Space Construction and Maintenance

The space environment presents unique challenges and opportunities in the assembly, inspection and maintenance of orbital and transit spaceflight systems. While conventional Extra-Vehicular Activity (EVA) technology, out of necessity, addresses each of the challenges, relatively few of the opportunities have been exploited due to crew safety and reliability considerations. Extra-Vehicular Robotics (EVR) is one of the least-explored design spaces but offers many exciting innovations transcending the crane-like Space Shuttle and International Space Station Remote Manipulator System (RMS) robots used for berthing, coarse positioning and stabilization. Microgravity environments can support new robotic archetypes with locomotion and manipulation capabilities analogous to undersea creatures. Such diversification could enable the next generation of space science platforms and vehicles that are too large and fragile to launch and deploy as self-contained payloads. Sinuous manipulators for minimally invasive inspection and repair in confined spaces, soft-stepping climbers with expansive leg reach envelopes and free-flying nanosatellite cameras can access EVA worksites generally not accessible to humans in spacesuits. These and other novel robotic archetypes are presented along with functionality concepts

Rehnmark, Fredrik↗

Novel intercore-cladding lithium niobate thin film coated MOEMS fiber sensor/modulator

A MOEMS fiber modulator/sensor is fabricated by depositing a lithium niobate sol-gel thin film between the core and cladding of a fiber preform. The preform is then drawn into 125-micron fibers. Such a MOEMS modulator design is expected to enhance existing lithium niobate undersea acousto-optic sound wave detectors. In our proposed version, the lithium niobate thin film alters the ordinary silica core/cladding boundary conditions such that, when a stress or strain is applied to the fiber, the core light confinement factor changes, leading to modulation of fiber light transmission. Test results of the lithium niobate embedded fiber with a 1550-nm, 4-mW laser source revealed a reduction in light transmission with applied tension. As a comparison, using the same laser source, an ordinary silica core/cladding fiber did not exhibit any reduction in transmitted light when the same strain was applied. Further experimental work and theoretical analysis is ongoing.

Jamlson, Tracee L.↗

NEPTUNE: an under-sea plate scale observatory

The NEPTUNE project will establish a linked array of undersea observatories on the Juan de Fuca tectonic plate. This observatory will provide a new kind of research platform for real-time, long-term, plate-scale studies in the ocean and Earth sciences.

shore station backbone↗

Chemical Sensing of Unexploded Ordnance with the Mobile Underwater Survey System (MUDSS)

The ability to sense explosives residues in the marine environment is a critical tool for identification and classification of underwater unexploded ordnance (UXO). Trace explosives signatures of TNT and DNT have been extracted from mulitple sediment samples adjacent to unexploded undersea ordnance at Halifax Harbor, Canada.

explosives electron attachment marine UXOs↗

Chemical sensor system

A chemical sensing apparatus and method for the detection of sub parts-per-trillion concentrations of molecules in a sample by optimizing electron utilization in the formation of negative ions is provided. A variety of media may be sampled including air, seawater, dry sediment, or undersea sediment. An electrostatic mirror is used to reduce the kinetic energy of an electron beam to zero or near-zero kinetic energy.

Darrach, Murray R.↗

The 'Biologically-Inspired Computing' Column

The field of Biology changed dramatically in 1953, with the determination by Francis Crick and James Dewey Watson of the double helix structure of DNA. This discovery changed Biology for ever, allowing the sequencing of the human genome, and the emergence of a "new Biology" focused on DNA, genes, proteins, data, and search. Computational Biology and Bioinformatics heavily rely on computing to facilitate research into life and development. Simultaneously, an understanding of the biology of living organisms indicates a parallel with computing systems: molecules in living cells interact, grow, and transform according to the "program" dictated by DNA. Moreover, paradigms of Computing are emerging based on modelling and developing computer-based systems exploiting ideas that are observed in nature. This includes building into computer systems self-management and self-governance mechanisms that are inspired by the human body's autonomic nervous system, modelling evolutionary systems analogous to colonies of ants or other insects, and developing highly-efficient and highly-complex distributed systems from large numbers of (often quite simple) largely homogeneous components to reflect the behaviour of flocks of birds, swarms of bees, herds of animals, or schools of fish. This new field of "Biologically-Inspired Computing", often known in other incarnations by other names, such as: Autonomic Computing, Pervasive Computing, Organic Computing, Biomimetics, and Artificial Life, amongst others, is poised at the intersection of Computer Science, Engineering, Mathematics, and the Life Sciences. Successes have been reported in the fields of drug discovery, data communications, computer animation, control and command, exploration systems for space, undersea, and harsh environments, to name but a few, and augur much promise for future progress.

Hinchey, Mike↗