Human Factors Experiments Research Articles

P‐132: Effect of Pre‐Alert Method for Visually Reduced Motion Dizziness for Vehicle Displays

Using displays such as smartphones, in‐car TVs or even fusion information on the side windows of a moving vehicle may cause motion sickness. A visual based pre‐alert method is presented to address the issue and a MSSQ method is applied to assess the sickness degree. A Human factors experiment has been conducted to demonstrate the effectiveness of the proposed method.

Temporal light modulation: A phantom array visibility measure

At temporal light modulation (TLM) frequencies between 80 Hz and 20 000 Hz observers may perceive a series of repeated images called the phantom array effect (PAE) when they move their eyes in large saccades across a modulating light source or across a scene lit by the modulating light source. To date, there is no well-established measure for quantifying PAE visibility, but there is growing awareness of the need for one among design professionals and sensitive populations. This paper documents a new measure, the phantom array visibility measure (PAVM), which is based on the results of recent human factors experiments. The measure follows the mathematical underpinning used by the flicker visibility measure and the stroboscopic visibility measure, where the time-domain TLM waveform is converted into its Fourier frequency components; each component is evaluated through a threshold curve of modulation depth, then summed through an equation employing a Minkowski exponent. This scales the PAVM so that a value of 1 indicates a waveform at a threshold visibility in the conditions of the underlying experiment.

What Tourists Observe in Historical Streets: An Empirical Study of Virtual Historical Street Spatial Perception Based on Eye Tracking and Human Factors Experiments

What Tourists Observe in Historical Streets: An Empirical Study of Virtual Historical Street Spatial Perception Based on Eye Tracking and Human Factors Experiments

Association between visual distance and students’ visual perception comfort in primary and secondary classrooms

ABSTRACT With developments in information technology, multimedia equipment and electronic teaching aids have been introduced into primary and secondary school classrooms. Thus, traditional “blackboards” have gradually given way to screens, ultimately complicating the visual environment and the visual act of looking at the blackboard. Generally, looking at the blackboard can affect the visual comfort of students when reading from different viewing distances. In this study, 40 primary school students were invited for a visual perception human-factor experiment in a secondary school classroom in Anshan, Liaoning Province, China. The Ergo LAB human-factor platform was used to test the students’ electrodermal indicators at different distances. Moreover, simultaneous subjective scoring was performed to compare and analyse the students’ state of arousal levels and visual perceptual comfort under different visual distance conditions. The acceptable visual distance for students to be able to read from an electronic screen ranged from 2.2 m to 8.5 m; the highest state of arousal and visual comfort were achieved at a visual distance of 4–4.9 m, and the most optimal visual distance was 5.8 m.

Impact Analysis of Situation Awareness Based on a Multitasking Difficulty Quantitative Model

Situation awareness (SA) is a key indicator of operator task performance and behavioral safety in Human-Machine Interaction (HMI), and task difficulty is an important influencing factors in establishing and maintaining SA, especially in safety-critical scenarios such as flying and nuclear. However, the complexity and diversity of multitasking make it difficult to quantify task difficulty, which to a certain extent limits the research on cognitive research. To solve this problem, we proposed an approach to quantifying task difficulty in multitasking and analyzed the effect of task difficulty on different levels of SA through experiments in this paper. First, a task difficulty measure for a single meta-task was developed based on Shannon’s information theory, including both discrete and continuous meta-tasks. Next, a three-dimensional attribute model of meta-tasks was proposed to measure the difficulty value added by concurrent tasks based on multiple resource theory. Finally, an experiment was conducted to measure SA at different levels based on SAGAT, and SA under different levels of task difficulty was analyzed. The results showed a strong negative correlation between SA and task difficulty. Specifically, compared to SA at the comprehension and prediction levels, SA at the perceptual level was more easily influenced by task difficulty. This study can provide some reference for the quantify of task difficulty in human factors experiments, the optimization of tasks in HMI, and the selection of operator attention allocation strategies.

Assessing human emotional responses to the design of public spaces around subway stations: a human factors research

Transit-oriented development (TOD) is a powerful urban planning strategy to enhance sustainability and provide socioeconomic benefits for cities. The human-centered design of public spaces around subway stations is a critical issue in TOD. In this study, a socio-technical system-based perspective was adopted to investigate the impact of using different design strategies in public spaces around subway stations on human emotional responses. The novelty of this study lies in performing a human factors experiment to examine human emotional reactions to outdoor public spaces surrounding transit stations using a comprehensive method combining physiological assessment and subjective self-report. Thirty-four participants were recruited for the experiment, which was conducted at the catchment areas of two subway stations in Nanjing, China. Urban design characteristics related to open space enclosure and visual elements, natural elements, pedestrian access, surrounding buildings or walls, and land use and activities were tested in both semi-underground and above-ground public spaces. Additionally, human emotions were assessed using the pleasure, arousal, and dominance model and by investigating the four response systems that predominantly reflect people’s emotional states. These results led to design and policy suggestions that could assist practitioners and researchers in selecting relevant approaches for human-oriented and place-based TOD planning.Graphical abstract

Fundus-Vascular Responses to Color Deviation Caused by Non-Oxidative Blue Filtering.

Aims Short-wavelength blue light damaged retina by the oxidative stress in the retinal pigment epithelial (RPE) cells. Filtering blue light from screen could reduce blue hazard, whereas it inevitably altered color-gamut coverage and color-deviation level. Although abnormal fundus-vascular density (FVD) sometimes indicated fundus disease, few researchers noticed its responses to the variation of color-gamut coverage and color-deviation level. Methods In this study, we performed cellular experiments and analyzed the RPE cell viabilities (CVs) in spectrums with different blue (455-475 nm) ratios to describe the corresponding oxidative-stress levels. Further, we investigated the effects of color-gamut and deviation on FVD variations during the screen-watching task using human factor experiments with 30 participants (university students, including 17 males and 13 females, 21 to 30 years old). Results RPE CVs were similar in different spectrums, implying that non-oxidative blue filtering hardly contributed to CV improvement. Color-deviation level seems to induce more significant effects on the visual function compared to color-gamut coverage, and MTF and FVD presents similar variation trends during the visual task. Conclusion Oxidative-free blue filtering contributed little to decrease retinal oxidative stress yet caused color-deviation increase, which caused significant FVD reduction.

Recommended methods for conducting human factors experiments on the subjective evaluation of colour rendition

This article explores the best practices for conducting psychophysical experiments that investigate how colour rendition influences the perception of architectural environments. We offer guidance that covers all stages of research from preliminary development to publication, focusing especially on experiments that investigate qualities such as perceived naturalness, vividness, preference or acceptability in response to changes in the spectral power distribution of light sources. This article is intended to be a consolidated guide for researchers and reviewers of this type of research. Key recommendations include: (1) New work should be motivated by clearly expressed research questions and, when possible, explicit hypotheses that build on the existing body of knowledge, (2) visual stimuli comprising spectral power distributions and visual targets should be deliberately engineered to probe the research questions, (3) experiments should be designed to lessen potential biases, (4) reporting of experimental conditions and statistical analyses should be thorough and (5) Results should be contextual, resisting overgeneralization that cannot be supported by the data. Our motivation is to encourage high-quality research that is credible and discourage poor quality research that slows scientific progress and misuses resources.

42‐2: Distinguished Paper: Effects of Luminance Contrast and Font Size on Dual‐Plane HUD Legibility (“The Double 007 Rule for HUDs”)

Head‐up displays (HUDs) can provide important driving information such as speed and navigation directly to a driver within their immediate field of view, and thus improve driving experience. Specifically, a dual‐plane AR‐HUD can provide drivers with larger images with richer information, more intuitive information presentation, and enhanced navigation features. To ensure driver comfort, proper presentation format of the text on the dual‐plane HUD needs to be investigated. A human factors experiment was conducted to explore proper luminance contrast and font size of the text on a HUD. Twenty older and nine mid‐age drivers were instructed to recognize letters in fourteen levels of font size under each of eight levels of luminance contrast (ranging from 1.2:1, to 8:1) on each plane. The best test performance was observed at a luminance contrast of 7:1. We report the minimum and upper bound of 95% confidence interval of legible vertical visual angle for 99.5% of older drivers at each level of luminance contrast. While the typical legibility rule of thumb for font height vs. distance on standard displays is .007 (also known as the Bond rule), our experiment suggests that double that size (0.014) was needed to cover 99.5% of older drivers at a contrast ratio of 1.2:1 on a HUD.

Effects of luminance contrast and font size on dual‐plane head‐up display legibility (“The Double 007 Rule for HUDs”)

AbstractHead‐up displays (HUDs) can provide important driving information such as speed and navigation directly to a driver within their immediate field of view. Specifically, a dual‐plane AR‐HUD can provide drivers with larger images with richer information, more intuitive information presentation, and enhanced navigation features. To ensure driver comfort, proper presentation format of the text on the dual‐plane HUD needs to be investigated. A human factors experiment was conducted to explore proper luminance contrast and font size of the text on a HUD. Twenty older and nine mid‐age drivers were instructed to recognize letters in 14 levels of font size under each of eight levels of luminance contrast (ranging from 1.2:1, to 8:1) on each plane. The best test performance was observed at a luminance contrast of 7:1. We report the minimum and upper bound of 95% confidence interval of legible vertical visual angle for 99.5% of older drivers at each luminance contrast level. Although the typical legibility rule of thumb for font height versus distance on standard displays is 0.007 (known as the Bond rule), our experiment suggests that double that size (0.014) was needed to cover 99.5% of older drivers at a contrast ratio of 1.2:1 on a HUD.

Perception Measurement of Interface Transparency on the Side of Living Commercial Streets in North China

Street space is a place where residents engage in daily activities, and its environmental design plays an important role in regulating the physical and mental comfort of people. However, the visual environment of street space is complex with many design elements, which is not conducive to grasping the design focus. Based on visual perception of comfort, the study deconstructs street space design into four basic elements: interface transparency, storefront density, interface colors and interface materials, and builds a virtual scene using SU software. The combination of human factors experiments and questionnaires is used to study the perception of street transparency, providing basic information and new research methods for the humanized design of the visual environment of street space.

Effects of Red Light on Circadian Rhythm: A Comparison Among Lamps With Similar Correlated Color Temperatures Yet Distinct Spectrums

Blue crest between the wavelength of 460 nm and 480 nm was reported to present melatonin suppression effects, whereas effects of red light on circadian rhythm regulation remain unclear. Spectrum plays an important role in circadian rhythm regulation, yet a lot of researches focused on the correlated color temperature, although a correlated color temperature value corresponds to various possible spectrums. Here, we performed human factor experiments with 3 lamps on 17 participants, comprising 9 males and 8 females. Our results showed that spectrums with high blue intensity tended to cause abnormal regulations of melatonin and cortisol, while the abnormalities were likely to be compensated by the 606-635-nm red light, which was indispensable for the photo-biological effects concerning circadian rhythm regulation. Abnormal circadian rhythm regulation was also found to be influenced by the illuminance, as abnormalities were significant in 500 lux whereas they were likely to disappear in 250 lux, implying the existence of threshold doses to trigger abnormities concerning circadian rhythm regulation. Furthermore, circadian rhythm responses were distinct between males and females. Our work may have implications for the development of light source, as we suggest that lighting source designers should increase the 606-635-nm intensity for bed room luminaires to decrease melatonin suppression effects.

A Connected Autonomous Vehicle Testbed: Capabilities, Experimental Processes and Lessons Learned

VENTURER was one of the first three UK government funded research and innovation projects on Connected Autonomous Vehicles (CAVs) and was conducted predominantly in the South West region of the country. A series of increasingly complex scenarios conducted in an urban setting were used to: (i) evaluate the technology created as a part of the project; (ii) systematically assess participant responses to CAVs and; (iii) inform the development of potential insurance models and legal frameworks. Developing this understanding contributed key steps towards facilitating the deployment of CAVs on UK roads. This paper aims to describe the VENTURER Project trials, their objectives and detail some of the key technologies used. Importantly we aim to introduce some informative challenges that were overcame and the subsequent project and technological lessons learned in a hope to help others plan and execute future CAV research. The project successfully integrated several technologies crucial to CAV development. These included, a Decision Making System using behaviour trees to make high level decisions; A pilot-control system to smoothly and comfortably turn plans into throttle and steering actuation; Sensing and perception systems to make sense of raw sensor data; Inter-CAV Wireless communication capable of demonstrating vehicle-to-vehicle communication of potential hazards. The closely coupled technology integration, testing and participant-focused trial schedule led to a greatly improved understanding of the engineering and societal barriers that CAV development faces. From a behavioural standpoint the importance of reliability and repeatability far outweighs a need for novel trajectories, while the sensor-to-perception capabilities are critical, the process of verification and validation is extremely time consuming. Additionally, the added capabilities that can be leveraged from inter-CAV communications shows the potential for improved road safety that could result. Importantly, to effectively conduct human factors experiments in the CAV sector under consistent and repeatable conditions, one needs to define a scripted and stable set of scenarios that uses reliable equipment and a controllable environmental setting. This requirement can often be at odds with making significant technology developments, and if both are part of a project’s goals then they may need to be separated from each other.

Imaging Quality and Fatigue Quantification of Ocular Optical System

Human eye is a special kind of optical system, and its imaging quality and fatigue level seem susceptible to the illumination. In this study we were sought to develop a novel method to quantify ocular fatigue more accurately, and to assess the influence of light environment on ocular fatigue. Human factor experiments were performed on a total of 1249 participants. Among all physiological parameters, only accommodation and the 12th aberration presented significant variations during visual tasks. We deducted the ocular fatigue equation based on these two parameters together with other structural data. Regression equation and neural network were also constructed as complements. As a test, we predicted the ocular fatigue accumulations in various visual tasks. It was implied the predicted fatigue accumulations fell in separate ranges. It seems the novel method developed in this study could predict ocular fatigue accurately, and provide guidance to luminaire design.

Anisotropic Vibration Tactile Model and Human Factor Analysis for a Piezoelectric Tactile Feedback Device.

Tactile feedback technology has important development prospects in interactive technology. In order to enrich the tactile sense of haptic devices under simple control, a piezoelectric haptic feedback device is proposed. The piezoelectric tactile feedback device can realize tactile changes in different excitation voltage amplitudes, different excitation frequencies, and different directions through the ciliary body structure. The principle of the anisotropic vibration of the ciliary body structure was analyzed here, and a tactile model was established. The equivalent friction coefficient under full-coverage and local-coverage of the skin of the touch beam was deduced and solved. The effect of system parameters on the friction coefficient was analyzed. The results showed that in the full-coverage, the tactile effect is mainly affected by the proportion of the same directional ciliary bodies and the excitation frequency. The larger the proportion of the same direction ciliary body is, the smaller the coefficient of friction is. The larger the excitation frequency is, the greater the coefficient of friction is. In the local-coverage, the tactile effect is mainly affected by the touch position and voltage amplitude. When changing the touch pressure, it has a certain effect on the change of touch, but it is relatively weak. The experiment on the sliding friction of a cantilever touch beam and the experiment of human factor were conducted. The experimental results of the sliding friction experiment are basically consistent with the theoretical calculations. In the human factor experiment, the effects of haptic regulation are mainly affected by voltage or structure of the ciliary bodies.

Human reliability analysis and optimization of manufacturing systems through Bayesian networks and human factors experiments: A case study in a flexible intermediate bulk container manufacturing plant

Human reliability analysis (HRA) and optimization in manufacturing systems are effective to reduce system failure. The purpose of this study is to examine the HRA and optimization through a Bayesian network (BN) model and human factors experiments (HFEs). This study was applied to a flexible intermediate bulk container manufacturing plant. The human physiological and psychological factors consisting of personal abilities of flexibility, coordination, memory, and attention were regarded as the only performance shaping factors in this study. With the BN model, the relationship between human factors and human errors was described qualitatively and the impact of the human factor on system failures was judged quantitatively. Then the workers’ abilities training with HFEs based on the fault diagnosis results was carried out. The total numbers of errors have been decreased by 69.06% and the system failure rate has been reduced significantly after training.

Everybody Needs Somebody Sometimes: Validation of Adaptive Recovery in Robotic Space Operations

This letter assesses an adaptive approach to fault recovery in autonomous robotic space operations, which uses indicators of opportunity, such as physiological state measurements and observations of past human assistant performance, to inform future selections. We validated our reinforcement learning approach using data we collected from humans executing simulated mission scenarios. We present a method of structuring human-factors experiments that permits collection of relevant indicator of opportunity and assigned assistance task performance data, as well as evaluation of our adaptive approach, without requiring large numbers of test subjects. Application of our reinforcement learning algorithm to our experimental data shows that our adaptive assistant selection approach can achieve lower cumulative regret compared to existing nonadaptive baseline approaches when using real human data. Our work has applications beyond space robotics to any application where autonomy failures may occur that require external intervention.

12. Information Management

As the electricity industry becomes increasingly competitive, knowledge concerning the capacity, constraints and reliability of the electric system will become a commodity of great value. Electricity markets can be fast changing; understanding the implications of these changes before others can give an important competitive advantage. Power systems, however, are characterized by extremely large sets of data that cover spatial, temporal and contingent dimensions.Therefore, the focus of this mini-track is on the management of the information associated with power markets and power systems. This year there were four accepted papers. The first paper, ?A virtual environment for protective relaying evaluation and testing? addresses the important issue of visualization of the power relaying systems using an interactive 3D approach. In electrical power, systems the relays are charged with protecting the electrical system from potentially catastrophic disturbances. For example, when lightning strikes an electric transmission lines it is the relays, which must quickly sense that there is a problem. They then direct the line's circuit breakers to open, de-energizing the line but hopefully saving the system. This paper presents exciting new work at modeling and testing relays using a virtual environment.The second paper, ?Simulation Environment for Development and Testing of Plug Compatible Power System Applications? looks at the important issue of software management in a large energy control center environment. Traditionally a single manufacturer using a proprietary approach has developed these systems. Such a closed system made it well nigh impossible for outside vendors to supply software components for the system. Thankfully, recent work by EPRI and others has resulted in the opening of the energy control center. The second paper in the session describes recent work in the development and testing of these new ?plug compatible? power system applications.The third paper, ?Optimization and Visualization of the North American Eastern Interconnect Power Market? looks at the optimization and visualization of a proposed power market covering the entire Eastern Interconnect power system. The Eastern Interconnect electrical system covers almost all of North America east of the Rocky Mountains. This paper investigates the potential for operating this entire system as a single regional transmission organization (RTO). Surprisingly, so long as the lines and generators are operating as planned, the paper concludes that there is sufficient low cost capacity and transmission to keep prices uniform across the system. However, loss of just a few key devices can quickly result in market segmentation.The last paper in the mini-track, ?Human Factors Analysis of Power System Visualizations? describes an experimental approach to formally testing the usability of different power system visualizations. Power systems are in need of new visualization techniques. However, hand in hand with this work there must be a formal testing of whether these new visualizations are actually helpful. The last paper in the mini-track describes some recent human factor experiments to help meet this critical need.

A Better Photometric Index of Photo-Biological Effect on Visual Function of Human Eye: Illuminance or Luminance?

The illuminance index has been widely used in the field of photometry, although the luminance contains more information on not only light intensity but also light direction. In this study, we clarify which photometric index is more competent to describe the influence of lighting environment on human eye. In this study, we propose a novel methodology to investigate the photo-biological effect of the lighting environment by human factor experiment. With the human factor experiments performed on 20 participants, we compare the variations of ocular responses during the Landolt-rings-counting visual task in lighting environments with similar illuminance while distinct luminance changes. With the same Correlated Color Temperature (CCT) and Spectral Power Distribution (SPD), optical performances with similar illuminance values present quite different influences on ocular responses, and the response variations are found to vary with luminance values. It is implied that the regularity of luminance influence on the ocular responses to lighting environment is likely to be dependent on luminance value instead of illuminance, and the photometric index luminance seems more appropriate to be used to assess the lighting quality in standards.

Modeling Human Difference Threshold in Perceiving Mechanical Properties From Force

We discuss an extension of the basic principles underlying the human haptic just noticeable difference (JND) in perceiving a manipulator's mechanical properties from force feedback. Two cases are studied: first, the JND in perceiving the stiffness of manipulators with various masses and, second, the JND in perceiving the damping of a combined mass–spring–damper system with varying stiffness and mass. The extended JND laws are obtained through mapping psychophysical findings to JND formulations based on frequency response functions. We first present two human-factor experiments in which subjects discriminated between different levels of manipulator stiffness/damping while moving the manipulator with a prescribed sinusoidal deflection. For the two testing cases, both JNDs violate Weber's law: Due to the increases in mass, the normalized stiffness JND (the Weber fraction) decreases as the reference stiffness level increases; the damping JND for a constant reference damping increases with higher combined responses of stiffness and mass. On the basis of weighting the frequency response magnitude of mechanical properties, we performed model identification that fit the experimental observations and extended the JND laws for the two testing cases. Our extended JND laws indicate that, first, the stiffness and mass affect the stiffness JND in the same way, the stiffness JND is a fixed proportion of the combined frequency response of stiffness and mass, and, second, the frequency response magnitude of the damping JND is a fixed proportion of the frequency response magnitude of the combined system (the mass–spring–damper system).