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At least 1,639 records · Page 91
All sourcesNASA NTRSDOE OSTI
NASA NTRS1988

A manned lunar outpost. Design considerations for three key elements in an initial manned lunar outpost

The Initial Manned Lunar Outpost (IMLO) is proposed as the initial permanent base for manned activities on the Moon. The study concentrated on identifying the equipment, support systems, and initial base configuration necessary to accomplish the various science, industrial and exploration activities planned. The primary concepts of the MLO were the use of hard modules for habitation areas creating a flexible, modular transportation system; designing a multi-functional vehicle; and using an overhead radiation protection system. The transportation system, dubbed the Lunar Mobile Surface Transport System (LMSTS), carries the hard modules to the surface of the moon and provides a method to move them to the desired location through the use of interchangeable pallets. The avionics pallets are changed-out with wheel and hitch pallets, transforming the LMSTS into a "tractor trailer" used with the Multi-Functional Vehicle (MFV). The modules are placed under the Regolith Support Structure (RSS) which provides a stable environment and radiation protection for the entire base. The overhead structure was chosen over simply burying the modules to provide a study on the advantages and disadvantages of this type of system. The advantages include easy access to the exterior of the modules, providing a protected area for vehicles and equipment used in EVA, and creating an area of constant temperature. Disadvantages include a need for prefabrication of structural components, including the preconstruction and construction phases of the initial MLO. The design approach taken considered existing and near-term materials and technology only, without the consideration of possible future building technologies.

Bell, Larry↗
NASA NTRS1988

Technology transfer: Imaging tracker to robotic controller

The transformation of an imaging tracker to a robotic controller is described. A multimode tracker was developed for fire and forget missile systems. The tracker locks on to target images within an acquisition window using multiple image tracking algorithms to provide guidance commands to missile control systems. This basic tracker technology is used with the addition of a ranging algorithm based on sizing a cooperative target to perform autonomous guidance and control of a platform for an Advanced Development Project on automation and robotics. A ranging tracker is required to provide the positioning necessary for robotic control. A simple functional demonstration of the feasibility of this approach was performed and described. More realistic demonstrations are under way at NASA-JSC. In particular, this modified tracker, or robotic controller, will be used to autonomously guide the Man Maneuvering Unit (MMU) to targets such as disabled astronauts or tools as part of the EVA Retriever efforts. It will also be used to control the orbiter's Remote Manipulator Systems (RMS) in autonomous approach and positioning demonstrations. These efforts will also be discussed.

Otaguro, M. S.↗
NASA NTRS1987

Space telerobotic systems: Applications and concepts

The definition of a variety of assembly, servicing, and maintenance missions has led to the generation of a number of space telerobot concepts. The remote operation of a space telerobot is seen as a means to increase astronaut productivity. Dexterous manipulator arms are controlled from the Space Shuttle Orbiter cabin or a Space Station module. Concepts for the telerobotic work system have been developed by the Lyndon B. Johnson Space Center through contracts with the Grumman Aerospace Corporation and Marin Marietta Corporation. These studies defined a concept for a telerobot with extravehicular activity (EVA) astronaut equivalent capability that would be controlled from the Space Shuttle. An evolutionary development of the system is proposed as a means of incorporating technology advances. Early flight testing is seen as needed to address the uncertainties of robotic manipulation in space. Space robotics can be expected to spin off technology to terrestrial robots, particularly in hazardous and unstructured applications.

Jenkins, L.↗
NASA NTRS1987

Report on the Stanford/Ames direct-link space suit prehensor

Researchers at the Center for Design Research at Stanford University, in collaboration with NASA Ames at Moffet Field, California, are developing hand-powered mechanical prehensors to replace gloves for EVA spacesuits. The design and functional properties of the first version Direct Link Prehensor (DLP) is discussed. It has a total of six degrees-of-freedom and is the most elaborate of three prehensors being developed for the project. The DLP has a robust design and utilizes only linkages and revolute joints for the drive system. With its anthropomorphic configuration of two fingers and a thumb, it is easy to control and is capable of all of the basic prehension patterns such as cylindrical or lateral pinch grasps. Kinematic analysis reveals that, assuming point contacts, a grasped object can be manipulated with three degrees-of-freedom. Yet, in practice more degrees-of-freedom are possible.

Jameson, J. W.↗
NASA NTRS1988

The effects of high energy particles on planetary missions

Researchers review the background and motivation for the detailed study of the variability and uncertainty of the particle environment from a space systems planning perspective. The engineering concern raised by each environment is emphasized rather than the underlying physics of the magnetosphere or the sun. Missions now being planned span the short term range of one to three years to periods over ten years. Thus the engineering interest is beginning to stretch over periods of several solar cycles. Coincidentally, detailed measurements of the environment are now becoming available over that period of time. Both short term and long term environmental predictions are needed for proper mission planning. Short term predictions, perhaps based on solar indices, real time observations, or short term systematics, are very useful in near term planning -- launches, EVAs (extravehicular activities), coordinated observations, and experiments which require the magnetosphere to be in a certain state. Long term predictions of both average and extreme conditions are essential to mission design. Engineering considerations are many times driven by the worst case environment. Knowledge of the average conditions and their variability allows trade-off studies to be made, implementation of designs which degrade gracefully under multi-stress environments.

Robinson, Paul A., Jr.↗
NASA NTRS1987

U.S. Space Station platform - Configuration technology for customer servicing

Features of the Space Station coorbiting and polar orbiting platforms (COP and POP, respectively) are described that will allow them to be configured optimally to meet mission requirements and to be assembled, serviced, and modified on-orbit. Both of these platforms were designed to permit servicing at the Shuttle using the remote manipulator system with teleoperated end effectors; EVA was planned as a backup and for unplanned payload failure modes. Station-based servicing is discussed as well as expendable launch vehicle-based servicing concepts.

Dezio, Joseph A.↗
NASA NTRS1987

Space Station flight telerobotic servicer functional requirements development

The Space Station flight telerobotic servicer (FTS), a flight robotic system for use on the first Space Station launch, is described. The objectives of the FTS program include: (1) the provision of an alternative crew EVA by supporting the crew in assembly, maintenance, and servicing activities, and (2) the improvement of crew safety by performing hazardous tasks such as spacecraft refueling or thermal and power system maintenance. The NASA/NBS Standard Reference Model provides the generic, hierarchical, structured functional control definition for the system. It is capable of accommodating additional degrees of machine intelligence in the future.

Oberright, John↗
NASA NTRS1988

Telerobotics for the efficient utilization of space

Telerobotics is a new technology that is being developed to perform remote manipulation in space. It seeks to accommodate the needs arising from a rapidly increasing investment in space assets and from the large costs deriving from human operations in space, especially EVA. Telerobotics applies advanced automation and artificial intelligence technology and combines the immediacy of execution of teleoperation (the replication at a distance of the physical motions of the operator) with the efficiency and precision of supervised robotic autonomy (the accomplishment of assignments through machine task decomposition and interpretation of sensor information). One of the key goals of this approach is the achievement of a seamless transition between teleoperation and supervised autonomy. The basis of this technology and of the NASA telerobotics research and development activities are described. They consist of five elements: core research, laboratory integration testbed, mission analysis, application demonstrations and flight experiments. Current advances, both in research and system integration are reported including the first integration of the laboratory testbed and quantitative comparisons obtained in a buoyant facility. Planned future goals are outlined.

Varsi, Giulio↗
NASA NTRS1988

The Flight Telerobotic Servicer Project and systems overview

As part of the Flight Telerobotic Servicer (FTS) project an advanced telerobotic system is being developed to assist in and reduce crew extravehicular activity (EVA) for the U.S. Space Station. The FTS will be used for assembly, maintenance, servicing, and inspection throughout the lifetime of the Space Station. A brief overview of the FTS program is given, and some of the technical and system engineering issues associated with the development of the FTS are explored. A key to the evolutionary capability of the FTS design is the NASREM (NASA Standard Reference Model for telerobot control system) architecture. This architecture provides the framework for future growth and permits a logical blend of teleoperation and autonomous operations as required.

Mccain, Harry G.↗
NASA NTRS1988

Ground operation of space-based telerobots will enhance productivity

Due to the limited human resources which will be available on the U.S. Space Station, automation and robotics technologies are being developed to enhance the productivity on the Space Station. The need for space telerobots which can be operated from the ground is explored, taking into consideration the resulting time delay, the technology involved, and some currently planned experiments. The proposed experiments include a remote link with the Kennedy Space Center robotics laboratory and the Telerobot Intelligent Interface Flight Experiment (TRIIFEX). It is concluded that there is a need to develop and implement ground-remote telerobotics technology which can effectively operate in the time-delay environment. This capability will enable servicing operations in polar and geosynchronous orbits and assist EVA astronauts on the Space Station.

Schober, Wayne R.↗
NASA NTRS1988

The Flight Telerobotic Servicer Program

The Flight Telerobotic Servicer (FTS) Program, initiated by NASA to provide new capabilities for task accomplishment in the space environment, is described. The FTS Program includes the following: a series of test flights, a ground-based supporting infrastructure, and a technology utilization and transfer process. The FTS Program strives to reduce Space Station dependence on crew EVA, improve crew safety, enhance crew utilization, provide remote servicing capabilities for platforms, and accelerate technology transfer from research to U.S. industry.

Townsend, John W., Jr.↗
NASA NTRS1988

Prediction of physical workload in reduced gravity

The background, development, and application of a methodology to predict human energy expenditure and physical workload in low gravity environments, such as a Lunar or Martian base, is described. Based on a validated model to predict energy expenditures in earth-based industrial jobs, the model relies on an elemental analysis of the proposed job. Because the job itself need not physically exist, many alternative job designs may be compared in their physical workload. The feasibility of using the model for prediction of low gravity work was evaluated by lowering body and load weights, while maintaining basal energy expenditure. Comparison of model results was made both with simulated low gravity energy expendiure studies and with reported Apollo 14 Lunar EVA expenditure. Prediction accuracy was very good for walking and for cart pulling on slopes less than 15 deg, but the model underpredicted the most difficult work conditions. This model was applied to example core sampling and facility construction jobs, as presently conceptualized for a Lunar or Martian base. Resultant energy expenditures and suggested work-rest cycles were well within the range of moderate work difficulty. Future model development requirements were also discussed.

Goldberg, Joseph H.↗
NASA NTRS1988

Lunar and Mars missions - Challenges for advanced life support

The development of a suite of scenarios is a prerequisite to the studies that will enable an informed decision by the United States on a program to meet the recently announced space policy goal to expand human presence beyond earth orbit. NASA's Office of Exploration is currently studying a range of initiative options that would extend the sphere of human activity in space to Mars and include permanent bases or outposts on the moon and on Mars. This paper describes the evolutionary lunar base and the Mars expedition scenarios in some detail so that an evaluation can be made from the point of view of human support and opportunities. Alternative approaches in the development of lunar outposts are outlined along with Mars expeditionary scenarios. Human environmental issues are discussed, including: closed loop life support systems; EVA systems; mobility systems; and medical support, physiological deconditioning, and psychological effects associated with long-duration missions.

Duke, Michael B.↗
NASA NTRS1988

Development of an advanced solid amine humidity and CO2 control system for potential Space Station Extravehicular Activity application

A system for removing metabolic carbon dioxide and water vapor from breathing air within a space suit during NASA Space Station EVA is discussed. The solid amine compound used is packed within a water-cooled metal foam matrix heat-exchanger to remove the exothermic heat of chemical reaction. Details of the design of a canister for humidity and carbon dioxide control and performance of the system are presented.

Nalette, Timothy A.↗
NASA NTRS1988

The recovery and utilization of space suit range-of-motion data

A technique for recovering data for the range of motion of a subject wearing a space suit is described along with the validation of this technique on an EVA space suit. Digitized data are 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. It is concluded that such data can be used in such applications as the animation of anthropometric computer models.

Reinhardt, AL↗
NASA NTRS1988

A simulation system for Space Station extravehicular activity

A simulation program has been developed which addresses the human factors required to provide a crewmember with productive information during Space Station EVA. The operation of the voice recognition and control system and helmet-mounted projection display in the Space Station Extravehicular Mobility Unit (EMU) is reviewed. The features of the simulation program are discussed, including logic flow, information types, and the man-machine interface techniques used in the simulation program, voice recognizer, and helmet-mounted display.

Marmolejo, Jose A.↗
NASA NTRS1988

Testing of materials for passive thermal control of space suits

An effort is underway to determine the coating material of choice for the AX-5 prototype hard space suit. Samples of 6061 aluminum have been coated with one of 10 selected metal coatings, and subjected to corrosion, abrasion, and thermal testing. Changes in reflectance after exposure are documented. Plated gold exhibited minimal degradation of optical properties. A computer model is used in evaluating coating thermal performance in the EVA environment. The model is verified with an experiment designed to measure the heat transfer characteristics of coated space suit parts in a thermal vacuum chamber. Details of this experiment are presented.

Squire, Bernadette↗
NASA NTRS1989

An assessment of the structural dynamic effects on the microgravity environment of a reference Space Station

An interim 'Permanently Manned Capability' Space Station configuration and one designated 'Assembly Complete' are modeled by FEM techniques in order to select forcing functions for modal transient response analysis and illustrate sample waveforms. In all, 114 applied-force cases have been executed to simulate such expected operational disturbances as crewmembers' treadmill exercises and EVAs. The present discussion of the results obtained give attention to the acceleration-response environment of the U.S. Laboratory's center grid-point. The magnitude of the acceleration responses obtained indicate that attenuation systems must be incorporated, or operational constraints must be instituted.

Del Basso, Steve↗