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At least 937 records · Page 52
All sourcesNASA NTRSDOE OSTI
NASA NTRS1987

A task-based metric for telerobotic performance assessment

A methodology is described for developing a task complexity index based on combining the six basic motion primitives (three translation, three orientation) with force control and accuracy requirements. The result of this development is a set of complexity values that can be assigned to the high-level task primitives derived from a relatively shallow top-down mission analysis. These values are then averaged to arrive at total average mission complexities, such as for the mission of exchanging the Hubble Space Telescope (HST) battery modules. Application of this metric to a candidate set of NASA Flight Telerobotic Servicer evaluation tasks is discussed using the HST battery module mission for an in-depth example.

Barnes, J. F.↗
NASA NTRS1973

The role of man in flight experiment payload missions. Volume 1: Results

It is pointed out that a controversy exists concerning the required role of man, and his attendant skills and levels of skills, for Sortie Lab operations. As a result, a study was conducted to generate a taxonomy of candidate crew roles which would: (1) be applicable across all experiments, and (2) be usable for Sortie scientists and engineers in determination of level of skill as well as type of skill. Nine basic roles were identified in the study, and the tasks associated with each were developed from a functional description of a generalized in-flight experiment. The functional analysis comprised the baseline for establishment of crew roles, with roles being defined as combinations of tasks, associated skills, and knowledges. A role classification scheme was developed in which the functions and tasks identified were allocated to each of the nine role types. This classification scheme is presented together with the significant results of the study.

Malone, T. B.↗
NASA NTRS2018

Vehicle Design Data Format and Process for a Complete TARIS and OLTARIS Radiation Analysis for Designers and Engineers

Protecting astronauts from space radiation is a complex task when it comes to modeling and simulation. This document shows what information is needed from a spacecraft designer using CAD (Computer-Assisted Design) at each phase of the design to enable the engineers to evaluate the design phase against space radiation limits to determine the suitability of the design for space flight. The current personal exposure limits are listed in NASA STD-3001. A proxy to determine the REID (Radiation Exposure Induced Death) in NASA STD-3001 is the whole body effective dose equivalent (E or effective dose). For short-term tissue effects, organ-averaged gray equivalent (G (sub T)) is used. The TARIS (Tool for the Assessment of Radiation In Space - for LaRC (Langley Research Center) engineers) and OLTARIS (On-Line TARIS) - for designers) systems are used to generate these response functions. The E can use ICRP60 or NASA Q-values. A possible space radiation design basis environment for short-term tissue effects is described and used in all analyses. A single space vehicle was designed with three astronaut configurations and two of those configurations were used in a storm shelter thickness perturbation analysis. Conversion of the data from the CAD model to input necessary for TARIS and OLTARIS is also discussed in detail with relevant examples.

Singleterry, Robert C.↗
NASA NTRS1992

Structured analysis and modeling of complex systems

The Aircrew Evaluation Sustained Operations Performance (AESOP) facility at Brooks AFB, Texas, combines the realism of an operational environment with the control of a research laboratory. In recent studies we collected extensive data from the Airborne Warning and Control Systems (AWACS) Weapons Directors subjected to high and low workload Defensive Counter Air Scenarios. A critical and complex task in this environment involves committing a friendly fighter against a hostile fighter. Structured Analysis and Design techniques and computer modeling systems were applied to this task as tools for analyzing subject performance and workload. This technology is being transferred to the Man-Systems Division of NASA Johnson Space Center for application to complex mission related tasks, such as manipulating the Shuttle grappler arm.

Strome, David R.↗
NASA NTRS1985

System analysis study of space platform and station accommodations for life sciences research facilities. Volume 2: Study results, attachment 2. Phase A: Conceptual design and programmatics

The study results from the conceptual design and programmatics segment of the Space Platform and Station Accommodation for Life Sciences Research Facilities. The results and significant findings of the conceptual design and programmatics were generated by these tasks: (1) the review and update engineering and science requirements; (2) analysis of life sciences mission transition scenario; (3) the review and update of key trade issues; (4) the development of conceptual definition and designs; and (5) the development of the work breakdown schedule and its dictionary, program schedule, and estimated costs.

Wiley, Lowell F.↗
NASA NTRS1997

A Human Factors Analysis of EVA Time Requirements

Human Factors Engineering (HFE) is a discipline whose goal is to engineer a safer, more efficient interface between humans and machines. HFE makes use of a wide range of tools and techniques to fulfill this goal. One of these tools is known as motion and time study, a technique used to develop time standards for given tasks. During the summer of 1995, a human factors motion and time study was initiated with the goals of developing a database of EVA task times and developing a method of utilizing the database to predict how long an EVA should take. Initial development relied on the EVA activities performed during the STS-61 (Hubble) mission. The first step of the study was to become familiar with EVA's, the previous task-time studies, and documents produced on EVA's. After reviewing these documents, an initial set of task primitives and task-time modifiers was developed. Data was collected from videotaped footage of two entire STS-61 EVA missions and portions of several others, each with two EVA astronauts. Feedback from the analysis of the data was used to further refine the primitives and modifiers used. The project was continued during the summer of 1996, during which data on human errors was also collected and analyzed. Additional data from the STS-71 mission was also collected. Analysis of variance techniques for categorical data was used to determine which factors may affect the primitive times and how much of an effect they have. Probability distributions for the various task were also generated. Further analysis of the modifiers and interactions is planned.

Pate, Dennis W.↗
NASA NTRS1995

Backward assembly planning with DFA analysis

An assembly planning system that operates based on a recursive decomposition of assembly into subassemblies, and analyzes assembly cost in terms of stability, directionality, and manipulability to guide the generation of preferred assembly plans is presented. The planning in this system incorporates the special processes, such as cleaning, testing, labeling, etc. that must occur during the assembly, and handles nonreversible as well as reversible assembly tasks through backward assembly planning. In order to increase the planning efficiency, the system avoids the analysis of decompositions that do not correspond to feasible assembly tasks. This is achieved by grouping and merging those parts that can not be decomposable at the current stage of backward assembly planning due to the requirement of special processes and the constraint of interconnection feasibility. The invention includes methods of evaluating assembly cost in terms of the number of fixtures (or holding devices) and reorientations required for assembly, through the analysis of stability, directionality, and manipulability. All these factors are used in defining cost and heuristic functions for an AO* search for an optimal plan.

Lee, Sukhan↗
NASA NTRS1994

Influence of the helicopter environment on patient care capabilities: Flight crew perceptions

Flight crew perceptions of the effect of the rotary wing environment on patient care capabilities have not been subject to statistical analysis. We hypothesized that flight crew perceived significant difficulties in performing patient care tasks during air medical transport. A survey instrument was distributed to a convenience sample of flight crew members from twenty flight programs. Respondents were asked to compare the difficulty of performing patient care tasks in rotary wing and standard (emergency department or intensive care unit) settings. Demographic data collected on respondents included years of flight experience, flights per month, crew duty position, and primary aircraft in which the respondent worked. Statistical analysis was performed as appropriate using Student's t-test, type 111 sum of squares, and analysis of variance. Alpha was defined as p is less than or equal to .05. Fifty-five percent of programs (90 individuals) responded. All tasks were rated significantly more difficult in the rotary wing environment. Ratings were not significantly correlated with flight experience, duty position, flights per month, or aircraft used. We conclude that the performance of patient care tasks are perceived by air medical flight crew to be significantly more difficult during rotary wing air medical transport than in hospital settings.

Meyers, K. Jeffrey↗
NASA NTRS1994

Muscle Feasibility for Cosmos Rhesus

The following tasks were proposed for the Cosmos project: 1) Complete recordings of all preflight candidates during performance of a foot pedal motor control task while in the space capsule mock-up. 2) Complete recordings of all preflight candidates during locomotion and postural tasks. 3) Complete recordings of 24-hour spontaneous cage activity in the two flight monkeys before and after flight and of at least three control (non-flight) monkeys after the flight has been completed. 4) Complete recordings of the foot pedal and motor control tasks during flight and postflight as scheduled. 5) Complete recordings of the vertical drop test pre, during and postflight for the two flight and three control monkeys. 6) Complete recordings of locomotion and posture tests of the two flight monkeys postflight. 7) Complete recordings of locomotion and postural tests of at least three control (non-flight) monkeys during the postflight period. 8) Recalibrate buckles of the two flight and of at least three control monkeys postflight. 9) Complete analysis of the 24 hour EMG recordings of all monkeys. 10) Complete analysis of the foot pedal, locomotor and postural motor control tasks for the two flight and three control monkeys. It was proposed that efforts in the first postflight year be concentrated on the two flight animals and three postflight animals.

Edgerton, V. Reggie↗
NASA NTRS2017

Summary Findings from the AVT-191 Project to Assess Sensitivity Analysis and Uncertainty Quantification Methods for Military Vehicle Design

A NATO symposium held in Greece in 2008 identified many promising sensitivity analysis and uncertainty quantification technologies, but the maturity and suitability of these methods for realistic applications was not clear. The NATO Science and Technology Organization, Task Group AVT-191 was established to evaluate the maturity and suitability of various sensitivity analysis and uncertainty quantification methods for application to realistic vehicle development problems. The program ran from 2011 to 2015, and the work was organized into four discipline-centric teams: external aerodynamics, internal aerodynamics, aeroelasticity, and hydrodynamics. This paper summarizes findings and lessons learned from the task group.

Benek, John A.↗
NASA NTRS1992

Backward assembly planning with DFA analysis

An assembly planning system that operates based on a recursive decomposition of assembly into subassemblies is presented. The planning system analyzes assembly cost in terms of stability, directionality, and manipulability to guide the generation of preferred assembly plans. The planning in this system incorporates the special processes, such as cleaning, testing, labeling, etc., that must occur during the assembly. Additionally, the planning handles nonreversible, as well as reversible, assembly tasks through backward assembly planning. In order to decrease the planning efficiency, the system avoids the analysis of decompositions that do not correspond to feasible assembly tasks. This is achieved by grouping and merging those parts that can not be decomposable at the current stage of backward assembly planning due to the requirement of special processes and the constraint of interconnection feasibility. The invention includes methods of evaluating assembly cost in terms of the number of fixtures (or holding devices) and reorientations required for assembly, through the analysis of stability, directionality, and manipulability. All these factors are used in defining cost and heuristic functions for an AO* search for an optimal plan.

Lee, Sukhan↗
NASA NTRS1977

Flexible data-management system

Combined ASRDI Data-Management and Analysis Technique (CADMAT) is system of computer programs and procedures that can be used to conduct data-management tasks. System was developed specifically for use by scientists and engineers who are confronted with management and analysis of large quantities of data organized into records of events and parametric fields. CADMAT is particularly useful when data are continually accumulated, such as when the need of retrieval and analysis is ongoing.

Pelouch, J. J., Jr.↗
NASA NTRS1989

Liquid rocket booster study. Volume 2, book 6, appendix 10: Vehicle systems effects

Three tasks were undertaken by Eagle Engineering as a part of the Liquid Rocket Booster (LRB) study. Task 1 required Eagle to supply current data relative to the Space Shuttle vehicle and systems affected by an LRB substitution. Tables listing data provided are presented. Task 2 was to evaluate and compare shuttle impacts of candidate LRB configuration in concert with overall trades of analysis activity. Three selected configurations with emphasis on flight loads, separation dynamics, and cost comparison are presented. Task 3 required the development of design guidelines and requirements to minimize impacts to the Space Shuttle system from all LRB substitution. Results are presented for progress to date.

Source record↗
NASA NTRS1995

In-plant testing of membranes to treat electroplating wastewater

This is the final report submitted for the work performed under the NASA Cooperative Agreement NCC3-301 for the project entitled 'In-Plant Testing of Membranes To Treat Electroplating Waste water'. The main objective of the research project was to determine if the crosslinked polyacrylic acid salt films developed by NASA scientists could be used for heavy metal removal from the wastewater generated by the metals-finishing or electroplating industry. A variety of tasks identified in the original proposal were completed. These included: (1) analysis of our industrial partner Aetna Plating's zinc electroplating process and its wastewater treatment needs for zinc removal; (2) design and construction of a laboratory-scale unit to continuously supply and remove the ion exchange films from the zinc wastewater; (3) performance of a series of runs on such a unit to determine its operating characteristics; and (4) design of a prototype unit for use at the industrial site. In addition, there were a number of tasks that had not been identified in the original proposal but were later judged to be necessary for the successful completion of the project. These were: (1) batch equilibrium and kinetic experiments with analysis of the experimental results to accurately determine the equilibrium and kinetic parameters for the ion exchange films; (2 ) simulation studies for proper design of the prototype unit; and (3) preliminary runs to exchange the films from H form to Calcium form.

Shah, D. B.↗
NASA NTRS1979

Design, fabrication and test of graphite/polyimide composite joints and attachments for advanced aerospace vehicles

The design and evaluation of built-up attachments and bonded joint concepts for use at elevated temperatures is documented. Joint concept screening, verification of GR/PI material, fabrication of design allowables panels, definition of test matrices, and analysis of bonded and bolted joints are among the tasks completed. The results provide data for the design and fabrication of lightly loaded components for advanced space transportation systems and high speed aircraft.

Koumal, D. E.↗
NASA NTRS1980

Heat storage capability of a rolling cylinder using Glauber's salt

The rolling cylinder phase change heat storage concept was developed to the point where a prototype design is completed and a cost analysis is prepared. A series of experimental and analytical tasks are defined to establish the thermal, mechanical, and materials behavior of rolling cylinder devices. These tasks include: analyses of internal and external heat transfer; performance and lifetime testing of the phase change materials; corrosion evaluation; development of a mathematical model; and design of a prototype and associated test equipment.

Herrick, C. S.↗
NASA NTRS1980

Tools to aid the specification and design of flight software, appendix B

The tasks that are normally performed during the specification and architecture design stages of software development are identified. Ways that tools could perform, or aid the performance, of such tasks are also identified. Much of the verification and analysis that is suggested is currently rarely performed during these early stages, but it is believed that this analysis should be done as early as possible so as to detect errors as early as possible.

Bristow, G.↗