Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “human dynamics”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS1997

Terminal Area Productivity Program: Dynamic Spacing Human Factors

Dynamic spacing human factors deals with the following human factors issues: define controller limits to incorporating dynamic changes in separation standards; identify timing, planning, and coordination strategies; and consider consistency with current practices, policies, and regulations. The AVOSS technologies will make it possible to reduce separation standards in the terminal area under certain meteorological conditions. This paper contains the following sections: Dynamic space human factors overview, Preliminary tests, and current research status & plans.

Kanki, Barbara G.↗
NASA NTRS1982

Modeling of human operator dynamics in simple manual control utilizing time series analysis

Time series analysis is applied to model human operator dynamics in pursuit and compensatory tracking modes. The normalized residual criterion is used as a one-step analytical tool to encompass the processes of identification, estimation, and diagnostic checking. A parameter constraining technique is introduced to develop more reliable models of human operator dynamics. The human operator is adequately modeled by a second order dynamic system both in pursuit and compensatory tracking modes. In comparing the data sampling rates, 100 msec between samples is adequate and is shown to provide better results than 200 msec sampling. The residual power spectrum and eigenvalue analysis show that the human operator is not a generator of periodic characteristics.

Agarwal, G. C.↗
NASA NTRS1972

Human operator dynamics for aural compensatory tracking

The human operator's ability to control using aural information only and using combined aural and visual displays was investigated for a simple tracking task. Tracking error was presented to the test subjects using one- and two-ear displays. For both displays the pitch of the tone represented the magnitude of the tracking error. The operator's aural control characteristics were modeled as a describing function plus a remnant. The effects on the measured describing function and remnant of different system dynamics, changes in the frequency content of the input and different displays were determined during the study. The describing function and remnant data indicate that humans can control as well with aural cues as with visual cues for the task considered. However, the reduction in operator time delays, expected because of the generally faster human response to aural stimuli, was not evident in the results. It was also determined that the operators could control equally well with either the one- or two-ear display.

Vinje, E. W.↗
NASA NTRS1984

Time series modeling of human operator dynamics in manual control tasks

A time-series technique is presented for identifying the dynamic characteristics of the human operator in manual control tasks from relatively short records of experimental data. Control of system excitation signals used in the identification is not required. The approach is a multi-channel identification technique for modeling multi-input/multi-output situations. The method presented includes statistical tests for validity, is designed for digital computation, and yields estimates for the frequency responses of the human operator. A comprehensive relative power analysis may also be performed for validated models. This method is applied to several sets of experimental data; the results are discussed and shown to compare favorably with previous research findings. New results are also presented for a multi-input task that has not been previously modeled to demonstrate the strengths of the method.

Biezad, D. J.↗
NASA NTRS1984

Time Series Modeling of Human Operator Dynamics in Manual Control Tasks

A time-series technique is presented for identifying the dynamic characteristics of the human operator in manual control tasks from relatively short records of experimental data. Control of system excitation signals used in the identification is not required. The approach is a multi-channel identification technique for modeling multi-input/multi-output situations. The method presented includes statistical tests for validity, is designed for digital computation, and yields estimates for the frequency response of the human operator. A comprehensive relative power analysis may also be performed for validated models. This method is applied to several sets of experimental data; the results are discussed and shown to compare favorably with previous research findings. New results are also presented for a multi-input task that was previously modeled to demonstrate the strengths of the method.

Biezad, D. J.↗
NASA NTRS1999

Multifractality in human heartbeat dynamics

There is evidence that physiological signals under healthy conditions may have a fractal temporal structure. Here we investigate the possibility that time series generated by certain physiological control systems may be members of a special class of complex processes, termed multifractal, which require a large number of exponents to characterize their scaling properties. We report on evidence for multifractality in a biological dynamical system, the healthy human heartbeat, and show that the multifractal character and nonlinear properties of the healthy heart rate are encoded in the Fourier phases. We uncover a loss of multifractality for a life-threatening condition, congestive heart failure.

Non-NASA Center↗
NASA NTRS1978

A study of the effect of forcing function characteristics on human operator dynamics in manual control

The effect of the spectrum of the forcing function on the human pilot dynamics in manual control was investigated. A simple compensatory tracking experiment was conducted, where the controlled element was of a second-order dynamics and the forcing function was a random noise having a dominant frequency. The dominant frequency and the power of the forcing function were two variable parameters during the experiment. The results show that the human pilot describing functions are dependent not only on the dynamics of the controlled element, but also on the characteristics of the forcing function. This suggests that the human pilot behavior should be expressed by the transfer function taking into consideration his ability to sense and predict the forcing function.

Washizu, K.↗
NASA NTRS1972

Digital modeling of human operator dynamics via class of Liapunov functions

A technique is described which is utilized for modeling human operator dynamics. The technique is based upon a model-reference system configuration and a class of Liapunov functions formulated for this purpose which possess variable characteristics. It is shown how such a class of Liapunov functions and their time derivatives is formulated. The crux of the formulation lies in three variable positive definite matrices used for the construction of the class of Liapunov functions. The form and order of these matrices depend upon the form and order of the error differential equation of the human operator model-reference system. These matrices can be modified to include nonlinear functions of the human operator model.

Mekel, R.↗
NASA NTRS2020

Exploring the human-nature dynamics of Hunga Tonga Hunga Ha'apai, Earth's newest landmass

This paper examines the human-nature dynamics of volcanic eruptions through a multidisciplinary exploration of the recently-formed Hunga Tonga Hunga Ha‘apai (HTHH) landmass in the Kingdom of Tonga. HTHH was formed in early 2015 in the Ha‘apai island group in southwestern Tonga. This landmass has persisted longer than expected, providing a rare opportunity to examine pathways of erosion and biological colonization, and offering a glimpse into the cultural dynamics of a continuously changing Polynesian seascape. In 2018 and 2019, a collaborative partnership between the Kingdomof Tonga, Sea Education Association (SEA), and the United States National Aeronautics and Space Administration (NASA) ran expeditions to HTHH to calibrate satellite observations via field, ship, and drone-based measurements. In accessing HTHH via SEA's sailing school vessel (SSV) the Robert C. Seamans, a team of scientists and students combined fieldwork in anthropology, oceanography, and physical volcanology to study micro- and macro-scale dynamics of this classical surtseyan eruption site. In this pathfinding paper, we discuss the value of involving students in the process of real-time scientific discovery with on-the-fly adaptive hypothesis testing; this collaborative project provided mutual benefit to initiatives in science and education by offering robust data collection, while expanding environmental and cultural literacy. Additionally, we integrate collaborative research on HTHH with ethnographic research to understand how this ever changing “sea of islands” or intimately interconnected island spaces impact social-cultural relations within Oceania. We emphasize the importance of such multidisciplinary research in understanding the complexity of human-nature relations in a rapidly changing world.

Emily B. Hite↗
NASA NTRS1988

Prediction and measurement of human pilot dynamic characteristics

An analytical and experimental study of human pilot control strategies in a manned rotorcraft simulation is described. The task simulated involves a low-speed, constant-altitude maneuvering task in which a head-down display is utilized to allow the pilot to track a moving hover point. The efficacy of the display law driving an 'acceleration symbol' is determined and the manner in which the prediction and measurement of pilot/vehicle dynamics can be made part of man/machine system evaluations is demonstrated.

Hess, Ronald A.↗
NASA NTRS2010

NATO Human View Architecture and Human Networks

The NATO Human View is a system architectural viewpoint that focuses on the human as part of a system. Its purpose is to capture the human requirements and to inform on how the human impacts the system design. The viewpoint contains seven static models that include different aspects of the human element, such as roles, tasks, constraints, training and metrics. It also includes a Human Dynamics component to perform simulations of the human system under design. One of the static models, termed Human Networks, focuses on the human-to-human communication patterns that occur as a result of ad hoc or deliberate team formation, especially teams distributed across space and time. Parameters of human teams that effect system performance can be captured in this model. Human centered aspects of networks, such as differences in operational tempo (sense of urgency), priorities (common goal), and team history (knowledge of the other team members), can be incorporated. The information captured in the Human Network static model can then be included in the Human Dynamics component so that the impact of distributed teams is represented in the simulation. As the NATO militaries transform to a more networked force, the Human View architecture is an important tool that can be used to make recommendations on the proper mix of technological innovations and human interactions.

Handley, Holly A. H.↗