
Research Highlights
Projects are organized by research topics and themes:
[Virtual Humans and Emotion] [Visual Attention in Virtual Reality] [Virtual Reality in Healthcare] [Virtual Agent Behavior Modeling] [Near-Field Perception and Calibration in Virtual Reality] [Self-Avatars in Virtual Reality] [Virtual Crowds, AI and User Studies] [Cybersickness in Virtual Reality] [Virtual Reality in STEM+C Education] [Virtual Reality Fidelity on Psychophysical Learning] [Fitts’ Law and Near-Field Virtual Reality] [Writing, Art and Notetaking in VR] [Haptics, Stereoscopy, Sensorimotor Congruence in VR] [Travel and Viewing on Spatial Cognition in VR] [Social Conversational Dialogue and Behaviors with Virtual Humans]Emotional Reactions to Virtual Humans

We investigated how virtual human animation and appearance fidelity affected the emotional reactions (emotion contagion) of participants in simulated inter-personal situations. Representative publications include the following:
Volante, M., Babu, S.V., Chaturvedi, H., Newsome, N., Ebrahimi, E., Roy, T., Daily, S.B. and Fasolino, T., 2016. Effects of virtual human appearance fidelity on emotion contagion in affective inter-personal simulations. IEEE transactions on visualization and computer graphics, 22(4), pp.1326-1335.
Wu, Y., Babu, S.V., Armstrong, R., Bertrand, J.W., Luo, J., Roy, T., Daily, S.B., Dukes, L.C., Hodges, L.F. and Fasolino, T., 2014. Effects of virtual human animation on emotion contagion in simulated inter-personal experiences. IEEE transactions on visualization and computer graphics, 20(4), pp.626-635.
Visual Attention to Virtual Humans and Navigational Aids in VR



We studied how virtual human animation and appearance fidelity affects visual attention (via eye tracking) of participants to virtual humans, and the interplay of visual attention and emotion, in simulated inter-personal situations. We also studied how visual attention to the virtual environment are affected by navigational aids in VR. Representative publications include the following:
Volonte, M., Anaraky, R.G., Venkatakrishnan, R., Venkatakrishnan, R., Knijnenburg, B.P., Duchowski, A.T. and Babu, S.V., 2021. Empirical evaluation and pathway modeling of visual attention to virtual humans in an appearance fidelity continuum. Journal on Multimodal User Interfaces, 15(2), pp.109-119.
Volonte, M., Duchowski, A.T. and Babu, S.V., 2019, July. Effects of a Virtual Human Appearance Fidelity Continuum on Visual Attention in Virtual Reality. In Proceedings of the 19th ACM International Conference on Intelligent Virtual Agents (pp. 141-147).
Volonte, M., Robb, A., Duchowski, A.T. and Babu, S.V., 2018, March. Empirical evaluation of virtual human conversational and affective animations on visual attention in inter-personal simulations. In 2018 IEEE Conference on Virtual Reality and 3D User Interfaces (VR) (pp. 25-32). IEEE.
Bertrand, J.W., Ebrahimi, E., Wachter, A., Luo, J., Babu, S.V., Duchowski, A.T., Meehan, N. and Gramopadhye, A.K., 2013, December. Visual Attention to Wayfinding Aids in Virtual Environments. In EGVE/EuroVR (pp. 9-16).
Virtual Reality Simulations for Healthcare Education and Training



We have designed, created and evaluated interactive simulations featuring virtual humans and multi-agent frameworks for applications involving patient surveillance, patient safety, hand hygiene and patient rapid deterioration education and training in healthcare situations. I have also designed and built large scale multi-screen virtual reality simulations for the research and treatment of balance disorders or vestibular dysfunction (with project leads at the University of Pittsburgh). Representative publications include the following:
Empirical Evaluation of Traditional vs. Hybrid Interaction Metaphors in a Multitask Healthcare Simulation. In 2013 IEEE International Conference on Healthcare Informatics (pp. 89-98). IEEE. (Best Paper Award)
Bloodworth, T., Cairco, L., McClendon, J., Hodges, L.F., Babu, S., Meehan, N.K., Johnson, A. and Ulinski, A.C., 2012. Initial evaluation of a virtual pediatric patient system. Carolinas Women in Computing.
Cairco, L., Bertrand, J., Gupta, M., Armstrong, R., Babu, S., Hodges, L. and Fasolino, T., 2012. Towards simulation training for nursing surveillance. Carolinas Women in Computing.
Bertrand, J., Babu, S.V., Gupta, M., Segre, A.M. and Polgreen, P., 2011, April. A 3D virtual reality hand hygiene compliance training simulator. In Scientific Meeting of the Society for Healthcare Epidemiology of America.
Bertrand, J., Babu, S.V., Polgreen, P. and Segre, A., 2010, September. Virtual agents based simulation for training healthcare workers in hand hygiene procedures. In International Conference on Intelligent Virtual Agents (pp. 125-131). Springer, Berlin, Heidelberg.
Whitney, S.L., Sparto, P.J., Babu, S.V., Hodges, L.F., Furman, J.M. and Redfern, M.S., 2007. Perceived anxiety in a virtual grocery store in persons with and without vestibular dysfunction. Annual Review of CyberTherapy and Telemedicine, p.206.
Whitney, S.L., Sparto, P.J., Babu, S.V., Hodges, L.F., Furman, J.M. and Redfern, M.S., 2007. Perceived anxiety and simulator sickness in a virtual grocery store in persons with and without vestibular dysfunction. Annual Review of CyberTherapy and Telemedicine, 5, pp.173-178.
Whitney, S.L., Sparto, P.J., Hodges, L.F., Babu, S.V., Furman, J.M. and Redfern, M.S., 2006. Responses to a virtual reality grocery store in persons with and without vestibular dysfunction. CyberPsychology & Behavior, 9(2), pp.152-156.
Virtual Agent Scenario Design and Behavior Modeling

We have designed and evaluated scenario design algorithms and behavior modeling subroutines for interactive virtual humans in VR simulations. These innovations have been employed in healthcare simulations with complex behaviors for virtual crowds and in virtual peer creation in bicycling simulators for injury prevention and traffic crossing safety research in children. Representative publications include the following:
Gupta, M., Bertrand, J.W., Babu, S.V., Polgreen, P. and Segre, A.M., 2012, January. An evolving multi-agent scenario generation framework for simulations in preventive medicine education. In Proceedings of the 2nd ACM SIGHIT International Health Informatics Symposium (pp. 237-246).
Chihak, B.J., Plumert, J.M., Ziemer, C.J., Babu, S., Grechkin, T., Cremer, J.F. and Kearney, J.K., 2010. Synchronizing self and object movement: how child and adult cyclists intercept moving gaps in a virtual environment. Journal of experimental psychology: human perception and performance, 36(6), p.1535.
Babu, S.V., Grechkin, T.Y., Chihak, B., Ziemer, C., Kearney, J.K., Cremer, J.F. and Plumert, J.M., 2010. An immersive virtual peer for studying social influences on child cyclists’ road-crossing behavior. IEEE transactions on visualization and computer graphics, 17(1), pp.14-25.
Grechkin, T., Babu, S., Ziemer, C., Chihak, B., Cremer, J., Kearney, J. and Plumert, J., 2009, September. How does a virtual peer influence children’s distance from the roadway when initiating crossing?. In Proceedings of the 6th Symposium on Applied Perception in Graphics and Visualization (pp. 129-129).
Near-Field Depth Perception and Perceptuo-Motor Calibration in VR


My students and I have conducted a large body of work in understanding how near-field depth perception operates in Virtual Reality, and how visuo-haptic and visuo-motor calibration can be used to enhance depth presentation and perception in personal space VR interaction. Representative publications include the following:
Ebrahimi, E., Hartman, L.S., Robb, A., Pagano, C.C. and Babu, S.V., 2018, March. Investigating the effects of anthropomorphic fidelity of self-avatars on near field depth perception in immersive virtual environments. In 2018 IEEE Conference on Virtual Reality and 3D User Interfaces (VR) (pp. 1-8). IEEE. (Best Paper Award)
Ebrahimi, E., Robb, A., Hartman, L.S., Pagano, C.C. and Babu, S.V., 2018, August. Effects of anthropomorphic fidelity of self-avatars on reach boundary estimation in immersive virtual environments. In Proceedings of the 15th ACM Symposium on Applied Perception (pp. 1-8).
Ebrahimi, E., Babu, S.V., Pagano, C.C. and Jörg, S., 2016. An empirical evaluation of visuo-haptic feedback on physical reaching behaviors during 3D interaction in real and immersive virtual environments. ACM Transactions on Applied Perception (TAP), 13(4), pp.1-21. (Best Paper Award)
Ebrahimi, E., Babu, S.V., Pagano, C.C. and Joerg, S., 2016, March. Towards a comparative evaluation of visually guided physical reach motions during 3D interactions in real and virtual environments. In 2016 IEEE symposium on 3D user interfaces (3DUI) (pp. 237-238). IEEE. (Best Poster Award)
Ebrahimi, E., Altenhoff, B.M., Pagano, C.C. and Babu, S.V., 2015, March. Carryover effects of calibration to visual and proprioceptive information on near field distance judgments in 3d user interaction. In 2015 IEEE Symposium on 3D User Interfaces (3DUI) (pp. 97-104). IEEE.
Ebrahimi, E., Altenhoff, B., Hartman, L., Jones, J.A., Babu, S.V., Pagano, C.C. and Davis, T.A., 2014, August. Effects of visual and proprioceptive information in visuo-motor calibration during a closed-loop physical reach task in immersive virtual environments. In Proceedings of the ACM Symposium on Applied Perception (pp. 103-110).
Altenhoff, B.M., Napieralski, P.E., Long, L.O., Bertrand, J.W., Pagano, C.C., Babu, S.V. and Davis, T.A., 2012, August. Effects of calibration to visual and haptic feedback on near-field depth perception in an immersive virtual environment. In Proceedings of the ACM symposium on applied perception (pp. 71-78).
Napieralski, P.E., Altenhoff, B.M., Bertrand, J.W., Long, L.O., Babu, S.V., Pagano, C.C., Kern, J. and Davis, T.A., 2011. Near-field distance perception in real and virtual environments using both verbal and action responses. ACM Transactions on Applied Perception (TAP), 8(3), pp.1-19.
Self-Avatars in Virtual Reality

We have built a body of work on creating realistic self-representations in virtual reality experiences and investigating how anthropomorphic and anthropometric fidelity of self-avatars affects affordances, perception-action coordination, and motor control. Representative publications include the following:
Bhargava, A., Venkatakrishnan, R., Venkatakrishnan, R., Solini, H., Lucaites, K.M., Robb, A., Pagano, C. and Babu, S., 2021. Did I Hit the Door Effects of Self-Avatars and Calibration in a Person-Plus-Virtual-Object System on Perceived Frontal Passability in VR. In IEEE Transactions on Visualization and Computer Graphics.
Bhargava, A., Solini, H., Lucaites, K., Bertrand, J.W., Robb, A., Pagano, C.C. and Babu, S.V., 2020, March. Comparative evaluation of viewing and self-representation on passability affordances to a realistic sliding doorway in real and immersive virtual environments. In 2020 IEEE Conference on Virtual Reality and 3D User Interfaces (VR) (pp. 519-528). IEEE.
Bhargava, A., Lucaites, K.M., Hartman, L.S., Solini, H., Bertrand, J.W., Robb, A.C., Pagano, C.C. and Babu, S.V., 2020. Revisiting affordance perception in contemporary virtual reality. Virtual Reality, 24(4), pp.713-724.
Day, B., Ebrahimi, E., Hartman, L.S., Pagano, C.C., Robb, A.C. and Babu, S.V., 2019. Examining the effects of altered avatars on perception-action in virtual reality. Journal of Experimental Psychology: Applied, 25(1), p.1.
Ebrahimi, E., Hartman, L.S., Robb, A., Pagano, C.C. and Babu, S.V., 2018, March. Investigating the effects of anthropomorphic fidelity of self-avatars on near field depth perception in immersive virtual environments. In 2018 IEEE Conference on Virtual Reality and 3D User Interfaces (VR) (pp. 1-8). IEEE. (Best Paper Award)
Ebrahimi, E., Robb, A., Hartman, L.S., Pagano, C.C. and Babu, S.V., 2018, August. Effects of anthropomorphic fidelity of self-avatars on reach boundary estimation in immersive virtual environments. In Proceedings of the 15th ACM Symposium on Applied Perception (pp. 1-8).
Virtual Crowds and AI, Affect Modeling, and User Behaviors in VR

We have investigated users’ emotional reactions, verbal and non-verbal behaviors to affective virtual crowds in virtual reality simulations. As part of this work, we have modeled the AI for virtual crowd movements, conversational interactions with users, goal oriented collaborative task performance, and emotionally rich behaviors. We have also rigorously studied how the medium of communication with virtual humans in crowd situations affects participants’ impressions, emotional reactions and verbal/non-verbal behaviors in virtual reality encounters. Representative publications include the following:
Volonte, M., Wang, C.C., Ebrahimi, E., Hsu, Y.C., Liu, K.Y., Wong, S.K. and Babu, S.V., 2021, March. Effects of language familiarity in simulated natural dialogue with a virtual crowd of digital humans on emotion contagion in virtual reality. In 2021 IEEE Virtual Reality and 3D User Interfaces (VR) (pp. 188-197). IEEE.
Volonte, M., Hsu, Y.C., Liu, K.Y., Mazer, J.P., Wong, S.K. and Babu, S.V., 2020, March. Effects of interacting with a crowd of emotional virtual humans on users’ affective and non-verbal behaviors. In 2020 IEEE Conference on Virtual Reality and 3D User Interfaces (VR) (pp. 293-302). IEEE.
Liu, K.Y., Volonte, M., Hsu, Y.C., Babu, S.V. and Wong, S.K., 2019. Interaction with proactive and reactive agents in box manipulation tasks in virtual environments. Computer Animation and Virtual Worlds, 30(3-4), p.e1881.
Cybersickness in Virtual Reality

Cybersickness is an impediment to widespread adoption of VR, and is similar to motion sickness in symptoms experienced in VR. We are investigating the viewing and perceptuo-motor aspects of cybersickness in virtual reality simulations. We created an VR driving simulator to study factors such as field-of-view, optic flow, locus of control of motion, depth-of-field, visuo-motor calibration, and presence on cybersickness in VR. We also created an autonomous vehicle emulator in VR to study the effects of simulated autonomous vehicle behaviors on rider experience and motion sickness in users. Representative publications include the following:
Lin, Y.X., Venkatakrishnan, R., Venkatakrishnan, R., Ebrahimi, E., Lin, W.C. and Babu, S.V., 2020. How the presence and size of static peripheral blur affects cybersickness in virtual reality. ACM Transactions on Applied Perception (TAP), 17(4), pp.1-18. (Best Paper Award)
Venkatakrishnan, R., Venkatakrishnan, R., Anaraky, R.G., Volonte, M., Knijnenburg, B. and Babu, S.V., 2020, March. A structural equation modeling approach to understand the relationship between control, cybersickness and presence in virtual reality. In 2020 IEEE Conference on Virtual Reality and 3D User Interfaces (VR) (pp. 682-691). IEEE.
Venkatakrishnan, R., Venkatakrishnan, R., Bhargava, A., Lucaites, K., Solini, H., Volonte, M., Robb, A., Lin, W.C. Lin, Y.X., and Babu, S.V. 2020, March. Comparative evaluation of the effects of motion control on cybersickness in immersive virtual environments. In 2020 IEEE Conference on Virtual Reality and 3D User Interfaces (VR) (pp. 672-681). IEEE.
Rastogi, V., Merco, R., Kaur, M., Rayamajhi, A., Gavelli, M., Papa, G., Pisu, P., Babu, S., Robb, A. and Martin, J., 2019. An Immersive Vehicle-in-the-Loop VR Platform for Evaluating Human-to-Autonomous Vehicle Interactions (No. 2019-01-0143). SAE Technical Paper.
Liu, K.Y., Volonte, M., Hsu, Y.C., Babu,Venkatakrishnan, R., Bhargava, A., Venkatakrishnan, R., Lucaites, K.M., Volonte, M., Solini, H., Robb, A.C., Pagano, C. and Babu, S.V., 2019, March. Towards an immersive driving simulator to study factors related to cybersickness. In 2019 IEEE Conference on Virtual Reality and 3D User Interfaces (VR) (pp. 1201-1202). IEEE.
Virtual Reality in Computational Thinking and STEM Education


We have created a rich body of work on using virtual reality for computational thinking and STEM education. Funded by two NSF grants, we have designed and developed VR simulations where middle school students create dance choreographies for a virtual human using visual programming to learn computational thinking, and undergraduate students can experiences simulated field experiences in VR for Geology education. Representative publications include the following:
Leonard, A.E., Daily, S.B., Jörg, S. and Babu, S.V., 2021. Coding moves: Design and research of teaching computational thinking through dance choreography and virtual interactions. Journal of Research on Technology in Education, 53(2), pp.159-177.
Lin, L., Parmar, D., Babu, S.V., Leonard, A.E., Daily, S.B. and Jörg, S., 2017, September. How character customization affects learning in computational thinking. In Proceedings of the ACM Symposium on Applied Perception (pp. 1-8).
Parmar, D., Isaac, J., Babu, S.V., D’Souza, N., Leonard, A.E., Jörg, S., Gundersen, K. and Daily, S.B., 2016, March. Programming moves: Design and evaluation of applying embodied interaction in virtual environments to enhance computational thinking in middle school students. In 2016 IEEE Virtual Reality (VR) (pp. 131-140). IEEE.
Isaac, J. and Babu, S.V., 2016, March. Supporting computational thinking through gamification. In 2016 IEEE Symposium on 3D User Interfaces (3DUI) (pp. 245-246). IEEE.
Leonard, A.E., Dsouza, N., Babu, S.V., Daily, S.B., Jörg, S., Waddell, C., Parmar, D., Gundersen, K., Gestring, J. and Boggs, K., 2015. Embodying and programming a constellation of multimodal literacy practices: Computational thinking, creative movement, biology, & virtual environment interactions. Journal of Language and Literacy Education, 11(2), pp.64-93.
Daily, S.B., Leonard, A.E., Jörg, S., Babu, S., Gundersen, K. and Parmar, D., 2015. Embodying computational thinking: Initial design of an emerging technological learning tool. Technology, Knowledge and Learning, 20(1), pp.79-84.
Daily, S.B., Leonard, A.E., Jörg, S., Babu, S. and Gundersen, K., 2014, March. Dancing alice: Exploring embodied pedagogical strategies for learning computational thinking. In Proceedings of the 45th ACM technical symposium on Computer science education (pp. 91-96).
Interaction and Display Fidelity on Psychomotor Skills Learning

Education and training are popular applications of VR. Our focus has been on near-field psychomotor skills learning in VR. We have created a large body of work examining how interaction and display fidelity of virtual reality systems affects psychomotor skills learning, with applications to mechanical and electrical technical education. This work was funded by grants from NSF and DOL. Representative publications include the following:
Bhargava, A., Bertrand, J.W., Gramopadhye, A.K., Madathil, K.C. and Babu, S.V., 2018. Evaluating multiple levels of an interaction fidelity continuum on performance and learning in near-field training simulations. IEEE transactions on visualization and computer graphics, 24(4), pp.1418-1427.
Bertrand, J., Bhargava, A., Madathil, K.C., Gramopadhye, A. and Babu, S.V., 2017, March. The effects of presentation method and simulation fidelity on psychomotor education in a bimanual metrology training simulation. In 2017 IEEE Symposium on 3D User Interfaces (3DUI) (pp. 59-68). IEEE.
Parmar, D., Bertrand, J., Babu, S.V., Madathil, K., Zelaya, M., Wang, T., Wagner, J., Gramopadhye, A.K. and Frady, K., 2016. A comparative evaluation of viewing metaphors on psychophysical skills education in an interactive virtual environment. Virtual Reality, 20(3), pp.141-157.
Bertrand, J., Brickler, D., Babu, S., Madathil, K., Zelaya, M., Wang, T., Wagner, J., Gramopadhye, A. and Luo, J., 2015, March. The role of dimensional symmetry on bimanual psychomotor skills education in immersive virtual environments. In 2015 IEEE Virtual Reality (VR) (pp. 3-10). IEEE.
Parmar, D., Bertrand, J., Shannon, B., Babu, S.V., Madathil, K., Zelaya, M., Wang, T., Wagner, J., Frady, K. and Gramopadhye, A.K., 2014, March. Interactive breadboard activity simulation (IBAS) for psychomotor skills education in electrical circuitry. In 2014 IEEE Symposium on 3D User Interfaces (3DUI) (pp. 181-182). IEEE.
Wang, T., Wagner, J.R., Madathil, K.C., Zelaya, M.I., Bertrand, J., Frady, K.K., Gramopadhye, A.K. and Babu, S.V., 2013, June. Interactive Three Dimensional Visualization Based Engineering Technology Education–Modeling and Animation. In 2013 ASEE Annual Conference & Exposition (pp. 23-796).
Zelaya, M.I., Madathil, K.C., Bertrand, J., Wang, T., Gramopadhye, A.K., Wagner, J.R. and Babu, S.V.D., 2013, June. An Investigation of the Information-Seeking Behaviors of Two-Year College Students Enrolled in Technology Programs. In 2013 ASEE Annual Conference & Exposition (pp. 23-182).
Fitts’ Law Evaluation of Efficiency of Near-Field VR Interaction


In a string of empirical evaluations, we have investigated how end-effector representation (i.e. controller vs. stylus vs. low and high fidelity virtual pointing), and the presence/absence of haptics, stereoscopic viewing and visuo-proprioceptive-haptic mismatch/congruence of users’ end-effector affects the efficiency of near-field selection and manipulation in virtual reality. Representative publications include the following:
Brickler, D., Teather, R.J., Duchowski, A.T. and Babu, S.V., 2020. A Fitts’ Law Evaluation of Visuo-haptic Fidelity and Sensory Mismatch on User Performance in a Near-field Disc Transfer Task in Virtual Reality. ACM Transactions on Applied Perception (TAP), 17(4), pp.1-20. (Honorable Mention for Best Paper – ACM SAP 2020)
Babu, S., Tsai, M.H., Hsu, T.W. and Chuang, J.H., 2020, September. An Evaluation of the Efficiency of Popular Personal Space Pointing versus Controller based Spatial Selection in VR. In ACM Symposium on Applied Perception 2020 (pp. 1-10).
Design and Evaluation of Novel Interaction Metaphors for Writing, Notetaking and Art in VR

We have designed novel 3D interaction metaphors for notetaking, handwriting and art work in virtual reality. Our notetaking interaction metaphors can be used in remote VR based learning environments, and we have facilitated art interactions such as sketching, coloring, and tracing in VR. We also conducted rigorous user studies to examine the effectiveness of our notetaking metaphors for learning, and examined the motor control participants have in handwriting and art work in VR as compared to real-world and VR with a self-avatar representation of the user. Representative publications include the following:
Hsu, C.H., Chung, C.H., Venkatakrishnan, R., Venkatakrlshnan, R., Wang, Y.S. and Babu, S.V., 2021, March. Comparative Evaluation of Digital Writing and Art in Real and Immersive Virtual Environments. In 2021 IEEE Virtual Reality and 3D User Interfaces (VR) (pp. 1-10). IEEE.
Chen, Y.T., Hsu, C.H., Chung, C.H., Wang, Y.S. and Babu, S.V., 2019, March. ivrnote: Design, creation and evaluation of an interactive note-taking interface for study and reflection in vr learning environments. In 2019 IEEE Conference on Virtual Reality and 3D User Interfaces (VR) (pp. 172-180). IEEE.
Haptics, Sensorimotor Congruence, Stereoscopy on Perception-Action

In a series of studies, we have explored how haptics (sense of touch), visual-proprioceptive-tactile congruence/mismatch, and aspects of stereoscopic viewing in VR affects users near-field perception-action coordination and motor control. In one series of experiments, we examined the effects of haptics, stereoscopic viewing, and sensorimotor congruence in a pick-and-place task on perception-action coordination. In another, we examined the effects of haptics and stereoscopic viewing on size perception of tangible objects in personal space interactions in VR. Representative publications include the following:
de Siqueira, A.G., Venkatakrishnan, R., Venkatakrishnan, R., Bharqava, A., Lucaites, K., Solini, H., Nasiri, M., Robb, A., Pagano, C., Ullmer, B. and Babu, S.V., 2021, March. Empirically Evaluating the Effects of Perceptual Information Channels on the Size Perception of Tangibles in Near-Field Virtual Reality. In 2021 IEEE Virtual Reality and 3D User Interfaces (VR) (pp. 1-10). IEEE.
Bhargava, A., Lucaites, K.M., Hartman, L.S., Solini, H., Bertrand, J.W., Robb, A.C., Pagano, C.C. and Babu, S.V., 2020. Revisiting affordance perception in contemporary virtual reality. Virtual Reality, 24(4), pp.713-724.
Brickler, D., Teather, R.J., Duchowski, A.T. and Babu, S.V., 2020. A Fitts’ Law Evaluation of Visuo-haptic Fidelity and Sensory Mismatch on User Performance in a Near-field Disc Transfer Task in Virtual Reality. ACM Transactions on Applied Perception (TAP), 17(4), pp.1-20. (Honorable Mention for Best Paper – ACM SAP 2020)
Brickler, D., Babu, S.V., Bertrand, J. and Bhargava, A., 2018, March. Towards evaluating the effects of stereoscopic viewing and haptic interaction on perception-action coordination. In 2018 IEEE Conference on Virtual Reality and 3D User Interfaces (VR) (pp. 1-516). IEEE.
Bhargava, A., Lucaites, K.M., Hartman, L.S., Solini, H., Bertrand, J.W., Robb, A.C., Pagano, C.C. and Babu, S.V., 2018, March. Towards revisiting passability judgments in real and immersive virtual environments. In 2018 IEEE Conference on Virtual Reality and 3D User Interfaces (VR) (pp. 513-514). IEEE.
Day, B., Ebrahimi, E., Hartman, L.S., Pagano, C.C. and Babu, S.V., 2017. Calibration to tool use during visually-guided reaching. Acta psychologica, 181, pp.27-39.
Ebrahimi, E., Babu, S.V., Pagano, C.C. and Jörg, S., 2016. An empirical evaluation of visuo-haptic feedback on physical reaching behaviors during 3D interaction in real and immersive virtual environments. ACM Transactions on Applied Perception (TAP), 13(4), pp.1-21. (Best Paper Award – ACM SAP 2016)
Effects of Travel and Viewing on Spatial Knowledge Acquisition in VR
In this research thrust, we deployed a virtual human framework in public setting in order to evaluate how users interact with virtual humans deployed as interactive virtual receptionists, office assistants, and Representative publications include the following:
Rudolph, B., Musick, G., Wiitablake, L., Lazar, K.B., Mobley, C., Boyer, D.M., Moysey, S., Robb, A. and Babu, S.V., 2020, October. Investigating the Effects of Display Fidelity of Popular Head-Mounted Displays on Spatial Updating and Learning in Virtual Reality. In International Symposium on Visual Computing (pp. 666-679). Springer, Cham.
Suma, E., Finkelstein, S., Reid, M., Babu, S., Ulinski, A. and Hodges, L.F., 2009. Evaluation of the cognitive effects of travel technique in complex real and virtual environments. IEEE Transactions on Visualization and Computer Graphics, 16(4), pp.690-702.
Suma, E.A., Babu, S. and Hodges, L.F., 2007, March. Comparison of travel techniques in a complex, multi-level 3d environment. In 2007 IEEE Symposium on 3D User Interfaces. IEEE. (Best Paper Award)
Zanbaka, C.A., Lok, B.C., Babu, S.V., Ulinski, A.C. and Hodges, L.F., 2005. Comparison of path visualizations and cognitive measures relative to travel technique in a virtual environment. IEEE Transactions on Visualization and Computer Graphics, 11(6), pp.694-705.
Jeong, D.H., Lee, C.S., Jeon, G.B., Song, C.G., Babu, S. and Hodges, L., 2005. Differentiation on information gathering ability in real and virtual world. In Proceedings of Pacific Graphics (pp. 157-159).
Zanbaka, C., Babu, S., Xiao, D., Ulinski, A., Hodges, L.F. and Lok, B., 2004, March. Effects of travel technique on cognition in virtual environments. In IEEE Virtual Reality 2004 (pp. 149-286). IEEE.
Social Conversational Dialogue and Behaviors with Virtual Humans


We have modeled and deployed virtual human frameworks in public spaces in order to conduct research on users reactions to interactive virtual humans in public social settings such as office assistants, receptionists, and interactive kiosks. We innovated techniques and methodologies in unobtrusive passerby sensing, person identification, social conversation modeling, action scheduling, natural speech and gesture based interaction with virtual humans deployed in public social settings. We conducted novel evaluations if virtual humans can effectively teach social conversational behaviors in a foreign culture when deployed as social simulators, as well as virtual humans as personal trainers and physiotherapists. Representative publications include the following:
Babu, S.V., Suma, E., Hodges, L.F. and Barnes, T., 2011. Learning cultural conversational protocols with immersive interactive virtual humans. International Journal of Virtual Reality, 10(4), pp.25-35.
Babu, S., Suma, E., Barnes, T. and Hodges, L.F., 2007, March. Can immersive virtual humans teach social conversational protocols?. In 2007 IEEE Virtual Reality Conference (pp. 215-218). IEEE.
Babu, S.V., 2007. Inter-personal social conversation in multimodal human-virtual human interaction (Doctoral dissertation, The University of North Carolina at Charlotte).
Babu, S., Schmugge, S., Barnes, T. and Hodges, L.F., 2006, August. “What would you like to talk about?” an evaluation of social conversations with a virtual receptionist. In International Workshop on Intelligent Virtual Agents (pp. 169-180). Springer, Berlin, Heidelberg.
Babu, S., Schmugge, S., Inugala, R., Rao, S., Barnes, T. and Hodges, L.F., 2005, September. Marve: a prototype virtual human interface framework for studying human-virtual human interaction. In International Workshop on Intelligent Virtual Agents (pp. 120-133). Springer, Berlin, Heidelberg.
Babu, S., Zanbaka, C., Jackson, J., Chung, T., Lok, B., Shin, M.C. and Hodges, L.F., 2005. Virtual human physiotherapist framework for personalized training and rehabilitation. In Graphics Interface (pp. 9-11).
Find a quiet place, use a humble pen.
Paul Simon