Showing papers in "Human Factors in 1977"
TL;DR: In this article, the authors present a short review of the combined compensatory, pursuit, and pursuit control properties of drivers and driver/vehicle systems in steering operations in steering operation.
Abstract: The dynamic control properties of drivers and driver/vehicle systems in steering operations have been widely investigated. This paper presents a short review of the combined compensatory, pursuit, ...
342 citations
TL;DR: Eye movements and fixations of five drivers were recorded and superimposed on a videotaped recording of the dynamic visual scene as they drove on a two-lane rural road and indicated that in driving through curves drivers direct foveal fixations to lateral placement cues rather than rely on peripheral vision.
Abstract: Eye movements and fixations of five drivers were recorded and superimposed on a videotaped recording of the dynamic visual scene as they drove on a two-lane rural road. The results showed that (1) on curved roads, the fixation pattern follows the road geometry, whereas on straight roads, the search behavior is less active, and most of the fixations are close to the focus of expansion. The results indicate that in driving through curves drivers direct foveal fixations to lateral placement cues rather than rely on peripheral vision; (2) the process of curve scanning begins in the approach zone prior to the curve itself, suggesting that perceptually the curve negotiating process precedes the curve by several seconds; (3) the search patterns on right and left curves are not symmetrical; visual excursions to the right on right curves are greater than eye movements to the left on left curves; and (4) fixation duration statistics may be related to accident rates on curves. Implications of this study for the location of curve warning signs are given.
156 citations
TL;DR: In this paper, the literature on manual control will be reviewed briefly with attention focused on the use of the internal model concept, and an application is given in the human control of large ships.
Abstract: Many human operator studies have used successfully the concept that the human operator performs his task on the basis of certain knowledge about the system to be controlled, called the internal mod...
92 citations
TL;DR: It appears that the mode effects hold for both problems and for both job roles assigned to the subjects, with significant differences among the communication modes.
Abstract: Two-man teams solved credible, 'real world' problems for which computer assistance has been or could be useful. Conversations were carried on in one of four modes of communication: typewriting, handwriting, voice, and natural unrestricted communication. Performance was assessed on three classes of dependent measures: time to solution, behavioral measures of activity, and linguistic measures. Significant differences among the communication modes were found in each of the three classes. This paper is concerned mainly with the results of the linguistic analyses. Linguistic performance was assessed with 182 measures, most of which turned out to be redundant and some of which were useless or meaningless. Those that remain show that although problems can be solved faster in the oral modes than in the hard-copy modes, the oral modes are characterized by many more messages, sentences, words, and unique words; much higher communication rates; but lower type-token ratios. Although a number of significant problem and job-role effects were found, there were relatively few significant interactions of modes with thsse variables. It appears, therefore, that the mode effects hold for both problems and for both job roles assigned to the subjects.
88 citations
TL;DR: In this article, mathematical models of the control behavior of human drivers while following another vehicle in single lane traffic are presented. But the focus is on the representation of the individual driver, rather than on such abstract parameters of multi-lane traffic as average density or average velocity.
Abstract: This paper is concerned with mathematical models of the control behavior of human drivers while following another vehicle in single lane traffic The emphasis is on the representation of the individual driver, rather than on such abstract parameters of multi-lane traffic as average density or average velocity Three basic types of approaches to representing the driver's control strategy are reviewed First is a classical control structure in which assumptions concerning the stimulus-response characteristics of the driver are included, and a form for his control strategy algorithm is assumed The second class of models is based on optimal control theory The major feature of this class of models is that an assumed performance index is explicitly included in the formulation, so that the driver's control strategy arises as a result of his attempts to minimize this index or criterion The third class of models reviewed in the paper are heuristic models, which arise from control theory The first of these, ter
88 citations
TL;DR: Recent experience with controlled flight into terrain accidents is examined, seeing them as the result of errors generated by a complex air traffic control system with ample opportunities for system-induced errors.
Abstract: Controlled flight into terrain accidents are those in which an aircraft, under the control of the crew, is flown into terrain (or water) with no prior awareness on the part of the crew of the impen...
75 citations
TL;DR: In an intelligent man-machine control system, control theory measures describing the operator's tracking performance can provide useful information concerning an operator's attentional slate, and this information may be used to implement adaptive aiding procedures.
Abstract: In an intelligent man-machine control system, control theory measures describing the operator's tracking performance can provide useful information concerning an operator's attentional slate. This ...
70 citations
TL;DR: In this article, a rating hypothesis is introduced which relates the numerical pilot opinion rating assigned to a particular vehicle and task to the numerical value of the index of performance resulting from an optimal pilot modeling procedure as applied to that vehicle and tasks.
Abstract: A brief review of some of the more pertinent applications of analytical pilot models to the prediction of aircraft handling qualities is undertaken The relative ease with which multiloop piloting tasks can be modeled via the optimal control formulation makes the use of optimal pilot models particularly attractive for handling qualities research To this end, a rating hypothesis is introduced which relates the numerical pilot opinion rating assigned to a particular vehicle and task to the numerical value of the index of performance resulting from an optimal pilot modeling procedure as applied to that vehicle and task This hypothesis is tested using data from piloted simulations and is shown to be reasonable An example concerning a helicopter landing approach is introduced to outline the predictive capability of the rating hypothesis in multiaxis piloting tasks
64 citations
TL;DR: In this article, the authors present several ways feedback control theory has been used to describe tracking behavior and several qualitative experimental techniques that can aid any researcher investigating behavior whose temporal patterning is critical and which involves fairly continuous changes over time.
Abstract: The present paper reviews several ways feedback control theory has been used to describe tracking behavior and several qualitative experimental techniques These techniques require only ordinal-level measurement and may aid any researcher investigating behavior whose temporal patterning is critical and which involves fairly continuous changes over time One possible application in the area of stuttering behavior is presented in detail to show how these techniques can provide useful insights and hypotheses Other suggested areas of application include the behavior of human social groups, motivational behavior, and emotional behavior
61 citations
TL;DR: In this paper, thirtynine men were tested on a total of six tasks; performance was measured on each task presented individually and on two complex tasks made up of three-task subsets.
Abstract: : Thirty-nine men were tested on a total of six tasks; performance was measured on each task presented individually and on two complex tasks made up of three-task subsets. The tasks measured monitoring, arithmetic, pattern-discrimination, tracking, and problem-solving performance. Two separate test sessions were conducted for each of the individual tasks and for each of the two complex tasks. Factor analyses were performed on the resultant data to determine if there would merge a time-sharing ability, defined as a reliable source of variance associated with complex performance but independent of simple-task performance of the constituent tasks. A factor was found that showed high loadings for two different monitoring tasks for complex performance but negligible loadings for these tasks for simple performance; separate independent factors were found for the two monitoring tasks when they were performed under simple-task conditions. The monitoring measures appear to possess properties that would be expected of measures of a time-sharing ability. The findings suggest that a suitable measure of time-sharing ability would be of value in the selection and screening of candidates for complex jobs. (Author)
52 citations
TL;DR: Within the limits of this study, performance tended to improve as environmental stress increased, however, subjects did suffer from lapses resulting in abnormally poor performance, which could provide an explanation for many so-called “pilot error” accidents.
Abstract: A fixed-base helicopter simulator was used to examine pilot performance as influenced by noise, vibration, and fatigue. Subjects flew the simulator for periods ranging between three and eight hours while exposed to vibrations (at 17 Hz) ranging from 0.1 to 0.3 g, and noise stimuli varying between 74 (ambient) and 100 dB. Despite reports of extreme fatigue on these long flights, subject performance did not degrade. Within the limits of this study, performance tended to improve as environmental stress increased. However, subjects did suffer from lapses resulting in abnormally poor performance. These lapses are probably of short duration (seconds) and occur at unpredictable times. If such lapses occur in actual flight, they could provide an explanation for many so-called 'pilot error' accidents.
TL;DR: Findings suggest that improvement on the tracking task is in the specific skill of tracking, while digit-processing improvement results from improved time-sharing ability.
Abstract: A one-dimensional compensatory tracking task and a digit-processing, reaction time task were combined to assess three aspects of training under time-sharing conditions: (1) manipulation of desired levels of dual-task performance: (2) training under equal and unequal task priorities: and (3) repeated sequencing of single/dual-task presentations. Six groups of 10 subjects each participated in the experiment. Larger performance improvements under time-sharing conditions were observed when desired performance indicators were computed relative to a dual-task rather than a single-task reference. Training under unequal task priorities revealed that tracking was more sensitive than the digit-processing task to priority differences. Tracking performance continued to improve during repeated single-task presentation, whereas digit processing improved only in the time-sharing conditions. These findings suggest that improvement on the tracking task is in the specific skill of tracking, while digit-processing improveme...
TL;DR: It was concluded that the semantic differential is a valid instrument for evaluating comprehension of symbolic sign messages and that it has advantages over other techniques.
Abstract: There is a need to develop and validate simple, inexpensive techniques for the evaluation of traffic sign messages. This paper examines the semantic differential (a paper-and-pencil test which meas...
TL;DR: In this paper, the optimal control model of the human operator to problems in display analysis is applied to the analysis of advanced display/control systems for a Terminal Configured Vehicle Model.
Abstract: Application of the optimal control model of the human operator to problems in display analysis is discussed Those aspects of the model pertaining to the operator-display interface and to operator information processing are reviewed and discussed The techniques are then applied to the analysis of advanced display/control systems for a Terminal Configured Vehicle Model results are compared with those obtained in a large, fixed-base simulation
TL;DR: Two newly designed fonts and the Lincoln/Mitre font are compared for legibility using tachistoscopic presentation and forced identification and revealed that the most severe confusions occur for different characters in different fonts.
Abstract: Two newly designed fonts and the Lincoln/Mitre font are compared for legibility using tachistoscopic presentation and forced identification. All three fonts were constructed with a matrix of 5 × 7 dots and were presented with a computer-generated display. The results were analyzed parametrically in terms of total identification errors and by conventional confusion matrices. The analysis showed significantly fewer errors with the font utilizing the largest number of dots per symbol than with either of the other two fonts. The confusion matrices revealed that the most severe confusions occur for different characters in different fonts.
TL;DR: The methodology of estimation and control theory is considered in terms of response, stability, estimation, and control of linear dynamic systems and the application of these results to modeling human behavior is considered with special emphasis on man-machine system models.
Abstract: The methodology of estimation and control theory is considered in terms of response, stability, estimation, and control of linear dynamic systems. Within the context of discrete-time systems, multi-input, multi-output, nth-order linear systems are discussed, and general results for optimal estimation, optimal control, and other topics are presented. The application of these results to modeling human behavior is considered with special emphasis on man-machine system models.
TL;DR: Results demonstrate that a significant increase in the incidence of long-duration blink closures occurred while subjects were intoxicated and in the frequency of blinks and long- duration closures as a function of time-on-task.
Abstract: Eyeblink frequency and closure durations were recorded while subjects operated a driver simulator. Two films were viewed wider both sober and intoxicated conditions. Results demonstrate that a significant increase in the incidence of long-duration blink closures occurred while subjects were intoxicated. There was also a significant increase in the frequency of blinks and long-duration closures as a function of time-on-task.
TL;DR: A design procedure for control and display systems in which levels of automation vary over a significant range is proposed, pointing out the need for performance-workload relations for control, which are fairly well understood, and performance- workload Relations for monitoring, about which little is known.
Abstract: This paper proposes a design procedure for control and display systems in which levels of automation vary over a significant range. The elements of the primary analysis tool (the Optimal Control Model of the Human Operator) are briefly reviewed, and the use of the model at three levels of specification (information level, display-element level, and display-format level) is discussed. Based on observation and pilot commentary, it is assumed that the pilot allocates his attention to control the aircraft to the desired level of performance, and then, with remaining capacity, to monitor displays. This facet of behavior is incorporated into the design procedure so that regardless of the level of control automation, all systems are compared at the same level of control performance. The design procedure is applied to the longitudinal control of a CH-47 helicopter. The procedure points out the need for performance-workload relations for control, which are fairly well understood, and performance-workload relations for monitoring, about which little is known.
TL;DR: In this paper, three characteristics of hardcopy maps, scale, interrelatedness of symbols, and standardized symbology, are reviewed and their implications for future map-related research and design are discussed.
Abstract: Three characteristics of hardcopy maps, scale, interrelatedness of symbols, and standardized symbology, are reviewed Their implications for future map-related research and design are discussed Research on types of coding used in visual displays is discussed in terms of its applicability to hardcopy maps Specific suggestions for hardcopy map design are based on the literature comparing different kinds of map products
TL;DR: No correlation was found between accident occurrence and biorhythmic criticality or low phase of cycle in cases in which the primary cause of the accident was attributed to pilot involvement and for those in which it was not.
Abstract: Biorhythms were calculated for over 4,000 pilots involved in general aviation accidents in 1972. Data were obtained from the files of the National Transportation Safety Board. Exact date and time o...
TL;DR: In this article, the authors used a driving simulator with a six-degree of freedom computer-generated display, a four degree of freedom physical motion system, and a three-channel sound system to determine the sensitivity of a secondary task to vehicle handling parameters and various driving conditions.
Abstract: A driving simulator with a six-degree of freedom computer-generated display, a four degree of freedom physical motion system, and a three-channel sound system was used to determine the sensitivity of a secondary task to vehicle handling parameters and various driving conditions. Six subjects drove a simulated vehicle with normal automobile handling and another six drove with degraded handling (slow response). Steering ratio and disturbance level were adjusted within each set of six subjects. A secondary task consisting of reading random digits aloud from a single-digit dashboard display was used to assess workload. Using a technique similar to that of Knowles (1963) and McDonald (1973), it was found that workload increased significantly as disturbance level increased. Furthermore, workload increased significantly with degraded vehicle handling. In contrast, increasing steering ratio did not produce a significant change in workload. These results indicate that the secondary task method can be used to asses...
TL;DR: This correlation is based on an uncertainty theoretical model which provides a quantitative approach for evaluating drivers' attention level in various traffic flow conditions and some applications to traffic flow phenomena are presented.
Abstract: Drivers' eye-movement amplitude and fixation duration are studied in four simulated traffic flow conditions: (1) within free-flow mode, (2) under maximum flow conditions, (3) within congested-flow mode, and (4) on an urban street between signalized intersections. Of major interest is the possible correlation between eye-movement data and drivers' attention demands. This correlation is based on an uncertainty theoretical model which provides a quantitative approach for evaluating drivers' attention level in various traffic flow conditions. Some applications to traffic flow phenomena are presented.
TL;DR: In this paper, the authors attempted to redress the balance by testing the assumption in respect of some 200 individual ROCs obtained from four vigilance experiments, and found that about half of the individual functions were of the curved form predicted by the equal-variance SDT model and hence support the view that vigilance performance can be interpreted in terms of this theoretical model of decision-making.
Abstract: By rigorous test, Broadbent and Gregory (1963) showed that the behavior of subjects in a vigilance task could be adequately described by the equal variance model of signal detection theory (SDT). Since then the model has been widely applied in the analysis and interpretation of numerous vigilance studies, but its goodness of fit to the data has been met by mere assumption. The present study attempted to redress the balance by testing the assumption in respect of some 200 individual ROCs obtained from four vigilance experiments. Although the analysis indicated that about half of the individual ROC functions were of the curved form predicted by the equal-variance SDT model and hence support the view that vigilance performance can be interpreted in terms of this theoretical model of decision-making, a substantial proportion (30%) of the individual functions were of a particular form whose presence is difficult to account for, if handled within the SDT framework. Other models which seem more appropriate are s...
TL;DR: An analysis of tracking error responses showed a statistically significant impairment of the performance of subjects less than 35 years old at a blood alcohol level of 50 mg% and subjects over the age of 35 had difficulty operating the equipment.
Abstract: This report describes an investigation of the effects of moderate levels of blood alcohol on ability to steer a constantly turning course in a fixed-base shadowgraph driving simulator. An analysis of tracking error responses showed a statistically significant impairment of the performance of subjects less than 35 years old at a blood alcohol level of 50 mg%. Subjects over the age of 35 had difficulty operating the equipment. It is suspected that part of the decrement experienced by the older subjects must be attributed to task difficulty artificially raised by mechanical limitations of the simulator.
TL;DR: The impact of human engineering standards on product designs was evaluated by a comparison of two display panels designed to the same standards, an analytical evaluation of two existing standards, and a survey of standard users.
Abstract: Results are presented for a research study intended to assess the impact of present human engineering standards on product design. The approach consisted of three basic steps: a comparison of two display panels to determine if, in fact, products designed to the same standards are truly standardized; a review of two existing standards to determine how well their information can be used to solve design problems; and a survey of human factors specialists to assess their opinions about standards. It is shown that standards have less than the desired influence on product design. This is evidenced by a lack of standardization between hardware designed under common standards, by deficiencies within the standards that detract from their usefulness and encourage users to ignore them, and by the respondents of the survey who consider standards less valuable than other reference sources for design implementation. Recommendations aimed at enhancing the use of standards are set forth.
TL;DR: This article provides generalized keying rate information in terms of the time between keystrokes, theTime between records and fields, and the burst rates for multiple keystroke in a typical data entry application.
Abstract: Designers of systems which provide for data entry from a keyboard are usually concerned about the rate and manner that keyed data will enter the system. This article provides generalized keying rate information in terms of the time between keystrokes, the time between records and fields, and the burst rates for multiple keystrokes. The time interval data is presented in the form of cumulative relative frequency distribution curves. The analyses are based on more than one million keystrokes of data that were collected with fifteen keypunch operators on an IBM 3741 data entry system in a typical data entry application.
TL;DR: A detailed item-by-item analytical review of two existing government human engineering standards and the results of a users' survey revealed formatting and organization problems in current human engineering Standards which detract from their utility to the designer.
Abstract: A detailed item-by-item analytical review of two existing government human engineering standards and the results of a users' survey on human engineering standards revealed formatting and organization problems in current human engineering standards which detract from their utility to the designer. Problems identified and recommended solutions are presented. The recommended solutions are primarily directed at improving the ability to retrieve data from the standards and as a result increasing the degree to which the human engineering discipline has an effect on design.
TL;DR: It was concluded that the Critical Task Tester has good potential for further use in evaluating human visual motor performance where small differences as a function of CNS depressants and other agents are of interest.
Abstract: This report describes an investigation which evaluated the ability of subjects, with or without alcohol, to perform a visual stimulus tracking task as presented by the Mark IV “Critical Task Tester,” a device developed by the Systems Technology Corporation, Hawthorne, California. Analysis of error responses showed a statistically significant impairment of performance at a blood alcohol level (BAL) as low as 50 mg%. The operator's effective time delay also was affected at a BAL of 50 mg%. It was concluded that the Critical Task Tester has good potential for further use in evaluating human visual motor performance where small differences as a function of CNS depressants and other agents are of interest.
TL;DR: A contact analog aircraft display is described in which an airplane-like predictor symbol depicts future airplane position and orientation and least-squares regression approximations for each of the six degrees of freedom of aircraft motion were calculated.
Abstract: : A predictor display shows the human operator future consequences of his immediate control inputs. A contact analog aircraft display is described in which an airplane-like predictor symbol depicts future airplane position and orientation. The standard method for obtaining the predictor information is to use a complete, fast-time model of the controlled vehicle. An alternative approach is presented in this paper in which least-squares, first-order, linear approximations for each of the six degrees of freedom of aircraft motion were calculated. Thirteen variables representing changes in positions and rate of change of positions were selected as parameters for the prediction equations. Separate sets of equations were determined for 7, 14, and 21 seconds prediction times and continuous, 1, and 3 seconds control neutralization assumption times. The advantages and disadvantages of this regression approach are discussed.
TL;DR: It was concluded that only the super-fin designs that were vented and had a large surface area are more efficient than the conventional fins tested.
Abstract: One female and six male subjects were used to evaluate the effectiveness of four modern “super-swimfin” designs when compared to a set of conventional fins. Oxygen consumption and heart rates were measured at a predetermined submaximal workload using a swimming ergometer. Times for kicking 22.9 m were also compared. The results demonstrated that significantly less oxygen was consumed during the trials in which the vented super-fins of large surface area were used than when the conventional fins were used. Significant VO2differences were also noted between super-fins, with large surface area, inflexible, or venturi designs resulting in the consumption of more oxygen than the others. A statistically significant linear correlation (r = −.90) was computed when comparing oxygen consumption to fin surface area. Flexibility of the fins was noted to be directly related to the speed that could be attained (r = .90). It was concluded that only the super-fin designs that were vented and had a large surface area are...