Shader Lamps Virtual Patients: the physical manifestation of virtual patients.

We introduce the notion of Shader Lamps Virtual Patients (SLVP) - the combination of projector-based Shader Lamps Avatars and interactive virtual humans. This paradigm uses Shader Lamps Avatars technology to give a 3D physical presence to conversational virtual humans, improving their social interactivity and enabling them to share the physical space with the user. The paradigm scales naturally to multiple viewers, allowing for scenarios where an instructor and multiple students are involved in the training. We have developed a physical-virtual patient for medical students to conduct ophthalmic exams, in an interactive training experience. In this experience, the trainee practices multiple skills simultaneously, including using a surrogate optical instrument in front of a physical head, conversing with the patient about his fears, observing realistic head motion, and practicing patient safety. Here we present a prototype system and results from a preliminary formative evaluation of the system.

Fathering: the relationship between fathers' residence, fathers' sociodemographic characteristics, and father involvement.

Literature and research examining father involvement has focused primarily on outcomes associated with the well-being and development of children. The contextual factors associated with fathers, and how these factors shape fathers' involvement with their young children, have received limited attention in this literature. Addressing this limitation, this study focuses on the relationship between fathers' residential status, age, race and ethnicity, educational attainment, financial status and father involvement. Results of the regression models indicate that fathers who reside with their children and fathers who are older are more involved with their children. Given these findings, policymakers, practitioners, and researchers have an opportunity to create and enhance policies and programs that may assist and support fathers in their development as parents and their involvement with their children.

Virtual Animals as Diegetic Attention Guidance Mechanisms in 360-Degree Experiences.

360-degree experiences such as cinematic virtual reality and 360-degree videos are becoming increasingly popular. In most examples, viewers can freely explore the content by changing their orientation. However, in some cases, this increased freedom may lead to viewers missing important events within such experiences. Thus, a recent research thrust has focused on studying mechanisms for guiding viewers' attention while maintaining their sense of presence and fostering a positive user experience. One approach is the utilization of diegetic mechanisms, characterized by an internal consistency with respect to the narrative and the environment, for attention guidance. While such mechanisms are highly attractive, their uses and potential implementations are still not well understood. Additionally, acknowledging the user in 360-degree experiences has been linked to a higher sense of presence and connection. However, less is known when acknowledging behaviors are carried out by attention guiding mechanisms. To close these gaps, we conducted a within-subjects user study with five conditions of no guide and virtual arrows, birds, dogs, and dogs that acknowledge the user and the environment. Through our mixed-methods analysis, we found that the diegetic virtual animals resulted in a more positive user experience, all of which were at least as effective as the non-diegetic arrow in guiding users towards target events. The acknowledging dog received the most positive responses from our participants in terms of preference and user experience and significantly improved their sense of presence compared to the non-diegetic arrow. Lastly, three themes emerged from a qualitative analysis of our participants' feedback, indicating the importance of the guide's blending in, its acknowledging behavior, and participants' positive associations as the main factors for our participants' preferences.

Augmented rotations in virtual reality for users with a reduced range of head movement.

INTRODUCTION: A large body of research in the field of virtual reality is focused on making user interfaces more natural and intuitive by leveraging natural body movements to explore a virtual environment. For example, head-tracked user interfaces allow users to naturally look around a virtual space by moving their head. However, such approaches may not be appropriate for users with temporary or permanent limitations of their head movement. METHODS: In this paper, we present techniques that allow these users to get virtual benefits from a reduced range of physical movements. Specifically, we describe two techniques that augment virtual rotations relative to physical movement thresholds. RESULTS: We describe how each of the two techniques can be implemented with either a head tracker or an eye tracker, e.g. in cases when no physical head rotations are possible. CONCLUSIONS: We discuss their differences and limitations and we provide guidelines for the practical use of such augmented user interfaces.

Implementation and Evaluation of a 50 kHz, 28µs Motion-to-Pose Latency Head Tracking Instrument.

This paper presents the implementation and evaluation of a 50,000-pose-sample-per-second, 6-degree-of-freedom optical head tracking instrument with motion-to-pose latency of 28µs and dynamic precision of 1-2 arcminutes. The instrument uses high-intensity infrared emitters and two duo-lateral photodiode-based optical sensors to triangulate pose. This instrument serves two purposes: it is the first step towards the requisite head tracking component in sub- 100µs motion-to-photon latency optical see-through augmented reality (OST AR) head-mounted display (HMD) systems; and it enables new avenues of research into human visual perception - including measuring the thresholds for perceptible real-virtual displacement during head rotation and other human research requiring high-sample-rate motion tracking. The instrument's tracking volume is limited to about 120×120×250 but allows for the full range of natural head rotation and is sufficient for research involving seated users. We discuss how the instrument's tracking volume is scalable in multiple ways and some of the trade-offs involved therein. Finally, we introduce a novel laser-pointer-based measurement technique for assessing the instrument's tracking latency and repeatability. We show that the instrument's motion-to-pose latency is 28µs and that it is repeatable within 1-2 arcminutes at mean rotational velocities (yaw) in excess of 500°/sec.

Social interaction in augmented reality.

There have been decades of research on the usability and educational value of augmented reality. However, less is known about how augmented reality affects social interactions. The current paper presents three studies that test the social psychological effects of augmented reality. Study 1 examined participants' task performance in the presence of embodied agents and replicated the typical pattern of social facilitation and inhibition. Participants performed a simple task better, but a hard task worse, in the presence of an agent compared to when participants complete the tasks alone. Study 2 examined nonverbal behavior. Participants met an agent sitting in one of two chairs and were asked to choose one of the chairs to sit on. Participants wearing the headset never sat directly on the agent when given the choice of two seats, and while approaching, most of the participants chose the rotation direction to avoid turning their heads away from the agent. A separate group of participants chose a seat after removing the augmented reality headset, and the majority still avoided the seat previously occupied by the agent. Study 3 examined the social costs of using an augmented reality headset with others who are not using a headset. Participants talked in dyads, and augmented reality users reported less social connection to their partner compared to those not using augmented reality. Overall, these studies provide evidence suggesting that task performance, nonverbal behavior, and social connectedness are significantly affected by the presence or absence of virtual content.

Effects of Unaugmented Periphery and Vibrotactile Feedback on Proxemics with Virtual Humans in AR.

In this paper, we investigate factors and issues related to human locomotion behavior and proxemics in the presence of a real or virtual human in augmented reality (AR). First, we discuss a unique issue with current-state optical see-through head-mounted displays, namely the mismatch between a small augmented visual field and a large unaugmented periphery, and its potential impact on locomotion behavior in close proximity of virtual content. We discuss a potential simple solution based on restricting the field of view to the central region, and we present the results of a controlled human-subject study. The study results show objective benefits for this approach in producing behaviors that more closely match those that occur when seeing a real human, but also some drawbacks in overall acceptance of the restricted field of view. Second, we discuss the limited multimodal feedback provided by virtual humans in AR, present a potential improvement based on vibrotactile feedback induced via the floor to compensate for the limited augmented visual field, and report results showing that benefits of such vibrations are less visible in objective locomotion behavior than in subjective estimates of co-presence. Third, we investigate and document significant differences in the effects that real and virtual humans have on locomotion behavior in AR with respect to clearance distances, walking speed, and head motions. We discuss potential explanations for these effects related to social expectations, and analyze effects of different types of behaviors including idle standing, jumping, and walking that such real or virtual humans may exhibit in the presence of an observer.

Fitting the Fractional Polynomial Model to Non-Gaussian Longitudinal Data.

As in cross sectional studies, longitudinal studies involve non-Gaussian data such as binomial, Poisson, gamma, and inverse-Gaussian distributions, and multivariate exponential families. A number of statistical tools have thus been developed to deal with non-Gaussian longitudinal data, including analytic techniques to estimate parameters in both fixed and random effects models. However, as yet growth modeling with non-Gaussian data is somewhat limited when considering the transformed expectation of the response via a linear predictor as a functional form of explanatory variables. In this study, we introduce a fractional polynomial model (FPM) that can be applied to model non-linear growth with non-Gaussian longitudinal data and demonstrate its use by fitting two empirical binary and count data models. The results clearly show the efficiency and flexibility of the FPM for such applications.

HuSIS: A Dedicated Space for Studying Human Interactions.

To support the study of effective human-surrogate interaction techniques and modalities, the Office of Naval Research awarded an equipment grant to support the development of a Human-Surrogate Interaction Space (HuSIS) at the University of Central Florida in the Institute for Simulation & Training. The HuSIS consists of a dedicated physical space, structures, and components designed specifically for carrying out controlled studies related to human-surrogate interactions. This article describes the motivation, design, and realization of the HuSIS and the benefits of the common data-collection and analysis framework developed for HuSIS research.

Walking a high beam: the balance between employment stability, workplace flexibility, and nonresident father involvement.

Compared with resident fathers, nonresident fathers are more likely to be unemployed or underemployed and less likely, when they are employed, to have access to flexible work arrangements. Although lack of employment stability is associated with lower levels of father involvement, some research shows that increased stability at work without increased flexibility is negatively related to involvement. Using data from the Fragile Families and Child Wellbeing Study (N = 895), the authors examined the relationship between nonresident fathers' employment stability, workplace flexibility, and father involvement. Results indicate that workplace flexibility, but not employment stability, is associated with higher levels of involvement. Policy and practice implications are discussed.