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Full-size pilot-controlled docking simulation of Apollo command and service module with lunar module using only visual information
Adressable interface unit for computerized visual information processing system of earth resources infrared data
Memory and display device uses cathodochromic material to store visual information and fast phosphor to recall information for display and electronic processing. Cathodochromic material changes color when bombarded with electrons, and is restored to its original color when exposed to light of appropiate wavelength.
Author identified significant preliminary results from the Ouachita portion of the Texoma frame of data indicate many potentials in the analysis and interpretation of ERTS data. It is believed that one of the more significant aspects of this analysis sequence has been the investigation of a technique to relate ERTS analysis and surface observation analysis. At present a sequence involving (1) preliminary analysis based solely upon the spectral characteristics of the data, followed by (2) a surface observation mission to obtain visual information and oblique photography to particular points of interest in the test site area, appears to provide an extremely efficient technique for obtaining particularly meaningful surface observation data. Following such a procedure permits concentration on particular points of interest in the entire ERTS frame and thereby makes the surface observation data obtained to be particularly significant and meaningful. The analysis of the Texoma frame has also been significant from the standpoint of demonstrating a fast turn around analysis capability. Additionally, the analysis has shown the potential accuracy and degree of complexity of features that can be identified and mapped using ERTS data.
The author has identified the following significant results. Preliminary results from the Texoma frame of data indicate many potentials in the analysis and interpretation of ERTS-1 data. It is believed that one of the more significant aspects of this analysis sequence has been the investigation of a technique to relate ERTS analysis and surface observation analysis. At present a sequence involving (1) preliminary analysis based solely upon the spectral characteristics of the data, followed by (2) a surface observation mission to obtain visual information and oblique color photography of particular points of interest in the test site area, appears to provide an extremely efficient technique for obtaining particularly meaningful surface observation data. Following such a procedure allows concentration on particular points of interest in the entire ERTS frame and thereby making the surface observation data obtained to be particularly significant and meaningful. The analysis of the Texoma frame has also been significant from the standpoint of demonstrating a fast turn around analysis capability. Additionally, the analysis has shown the potential accuracy and degree of complexity of features that can be identified and mapped using ERTS-1 data.
Method has been developed for doping lithium niobiate crystals with transition metal to increase rate at which crystal can record optical data. Discovery may facilitate development of system for analog storage of TV frames, printed pages, photographs, and other visual information.
A laboratory study was conducted to investigate the effect of spurious simulator yaw motions on a pilot's control performance. A second objective was to compare the efficiency of static and dynamic simulator tracking in previously unexamined vehicle dynamics. Twelve airline pilots served as subjects in a moving-base flight simulator under congruent-motion, spurious-motion, and no-motion conditions. The results indicated a significant increase in the amount of error with increasing levels of spurious motion during the initially administered series of trials. The influence of spurious motion, however, was absent in a second series of trials. The data suggest that the pilots learned to compensate in their performance for the spurious inputs. It was also found that congruent visual and rotational cueing produced superior performance to that of tracking with visual information alone.
A zero gravity processing furnace system was designed that will allow acquisition of photographic or other visual information while the sample is being processed. A low temperature (30 to 400 C) test model with a flat specimen heated by quartz-halide lamps was constructed. A high temperature (400 to 1000 C) test model heated by resistance heaters, utilizing a cylindrical specimen and optics, was also built. Each of the test models is discussed in detail. Recommendations are given.
In order to evaluate the influences of touch and pressure cues on human spatial orientation, blindfolded subjects were exposed to 30 rmp rotation about the Z-axis of their bodies while the axis was horizontal or near horizontal. It was found that the manipulation of pressure patterns to which the subjects are exposed significantly influences apparent orientation. When provided with visual information about actual orientation the subjects will eliminate the postural illusions created by pressure-cue patterns. The localization of sounds is dependent of the apparent orientation and the actual pattern of auditory stimulation. The study provides a basis for investigating: (1) the postural illusions experienced by astronauts in orbital flight and subjects in the free-fall phase of parabolic flight, and (2) the spatial-constancy mechanisms distinguishing changes in sensory afflux conditioned by a subject's movements in relation to the environment, and those conditioned by movements of the environment.
A historical perspective is presented in terms of the major features and status of two families of computer simulation models in which the human operator plays the primary role. Both task oriented and message oriented models are included. Two other recent efforts are summarized which deal with visual information processing. They involve not whole model development but a family of subroutines customized to add the human aspects to existing models. A global diagram of the generalized model development/validation process is presented and related to 15 criteria for model evaluation.
Using a technique that requires a subject to consult an imagined or remembered spatial array while performing a visual task, a reliable reduction in the number of directed eye movements that are available for the acquisition of visual information is shown.
Using a technique that requires a subject to consult an imagined or remembered spatial array while performing a visual task, a reliable reduction in the number of directed eye movements that are available for the acquisition of visual information is shown.
The TAC BRAWLER air combat simulation models both the acquisition and use of visual information by the pilot. It was used to provide the designers of manned simulators for air-to-air combat with information regarding the training implications of display system resolution, inherent target contrast, field of view, and transport delay. Various display designs were simulated, and the resulting quantitative and qualitative differences in engagements were considered indicators of possible mistraining. Display resolution was found to alter combats primarily through its effect on detection ranges; the 'pixel averaging' contrast management technique was shown to largely compensate for this problem. Transport delay significantly degrades pilot tracking ability, but the training impact of the effect is unclear.
The results are presented of a study which uses fuzzy sets to model a Space Shuttle pilot's reasoning and actions while performing rendezvous proximity operation maneuvers. In this model fuzzy sets are used to simulate smooth and continuous actions as would be expected from an experienced pilot and to simulate common sense reasoning in the decision process. The present model assumes visual information available to the Shuttle pilot from the Shuttle Crew Optical Alignment Sighting (COAS) device and the overhead window and rendezvous radar sensor information available to him from an onboard display. This model will be used in a flight analysis simulator to perform studies requiring a large number of runs, each of which currently needs an engineer in the loop to supply the piloting decisions. This work has much broader implications in control of robots such as the Flight Telerobotic Servicer, in automated pilot control and attitude control, and in advisory and evaluation functions that could be used for flight data monitoring or for testing of various rule sets in flight preparation.
Hypothetical schemes for neural representation of visual information can be expressed as explicit image codes. Here, a code modeled on the simple cells of the primate striate cortex is explored. The Cortex transform maps a digital image into a set of subimages (layers) that are bandpass in spatial frequency and orientation. The layers are sampled so as to minimize the number of samples and still avoid aliasing. Samples are quantized in a manner that exploits the bandpass contrast-masking properties of human vision. The entropy of the samples is computed to provide a lower bound on the code size. Finally, the image is reconstructed from the code. Psychophysical methods are derived for comparing the original and reconstructed images to evaluate the sufficiency of the code. When each resolution is coded at the threshold for detection artifacts, the image-code size is about 1 bit/pixel.
The ability of a subject flying an experimental flight to use the different sources of visual information by looking at the vertical tracking error was investigated using a 3 (altitude) x 3 (texture) x 2 (replication) factorial design. Each subject flew these 18 flights in the same partially counterbalanced order, constructed such that there was one flight at each of the three altitudes, and over each of the three surface textures within each successive set of three flights. The three ground-surface textures used consisted of meridian, latitudinal, and square textures described by Wolpert et al. (1983). The results showed that, in displays where only splay information was available, the subjects tended to confuse lateral motion with vertical.
The dynamic response properties of horizontal vestibulo-ocular reflex (VOR) and optokinetic reflex (OKR) were characterized in 216 human subjects ranging in age from 7 to 81 years. The object of this cross-sectional study was to determine the effects of aging on VOR and OKR reflex dynamics, and to identify the distributions of parameters which describe VOR and OKR responses to pseudorandom stimuli in a putatively normal population. In general, VOR and OKR response parameters changed in a manner consistent with declining function with increasing age. For the VOR this was reflected in declining response amplitudes, although the magnitude of the decline was small relative to the variability of the data. For the OKR the lag time of the response, probably associated with the time required for visual information processing, increased linearly with age at a rate of about 1 ms per year.
The effects of internal depth within a simulation display on perceived changes in orientation have been studied. Subjects monocularly viewed displays simulating observer motion within a volume of randomly positioned points through a window which limited the field of view to 15 deg. Changes in perceived spatial orientation were measured by changes in posture. The extent of internal depth within the display, the presence or absence of visual information specifying change in orientation, and the frequency of motion supplied by the display were examined. It was found that increased sway occurred at frequencies equal to or below 0.375 Hz when motion at these frequencies was displayed. The extent of internal depth had no effect on the perception of changing orientation.