Research group: Perception and Action in Virtual Environments (PAVE)

Supervisor: Ph. D. Betty Mohler

I am a PhD student in Max-Planck-Institute for Biological Cybernetics. My research concentrates mostly on perception in immersive virtual environments (VEs) and more specifically space perception and body perception. People perceive the virtual world in a different way than they perceive the real world. Understanding the reasons underlying this effect will help us use the VEs more efficiently for different purposes, such as training, prototyping, education, basic science questions, interactive storytelling or rehabilitation.

I am currently working on one tandem project in collaboration with Philosophers (Dr. Hong Yu Wong and Catherine Stinson) from the Centre for Integrative Neuroscience (CIN) Tübingen:

• Body perception in VEs, in which we are interested in gaining more insights of how does visual embodiment affect perception and action.

My previous projects:

• Egocentric distance perception, in which we investigate the difference between distance perception in the VEs compared to the real world. For this study we use a 3D replication of a real-world room. I modeled the 3D model as I joined MPI for a six-weeks internship. More information about this project you can find in our paper published at APGV 2010.
• Animation of medical training scenarios – the aim of this project is to increase the effectiveness of medical training simulations by helping trainees gain a better understanding of the importance of communication and teamwork. Therefore we are developing an on-line application, which enables trainees to view the scenario from different perspectives or to freely explore the environment perception (you can see an example of this work here). Thus we can study the impact of the different perspectives on the users’ perception. The results of these studies can be used to improve the effectiveness of training. We created a pipeline for rapid and realistic reconstruction of medical scenarios, involving realistic virtual humans with realistic motions and ability to express emotions. We tested their ability to convey specific emotions in a user study published in JVRC 2010, which won "Best Short Paper Award". Further we tested and improved our pipeline in a paper published at CASA 2011 and in a paper will appear in MMVR 2012.

Medical Training Using Perspective Taking in Virtual Reality

Ivelina Alexandrova, Betty Mohler, Heinrich H. Bülthoff

Introduction

The aim of this work is to increase the effectiveness of medical training simulations by helping trainees gain a better understanding of the importance of communication and teamwork. Therefore we develop an application that can be used together with Real World (RW) simulations to improve training. Our application allows students to take the perspective of their teammates or the patient, while observing realistically reconstructed medical scenarios in a Virtual Environment (VE).

Goals

Our goal is to develop a virtual (on-line or immersive VE) application that can be used as an additional tool to the RW simulations for effective medical training at the university hospital. Therefore we first establish a pipeline to rapidly and realistically generate animations of medical scenarios.

Methods

We developed a pipeline which combines body animations extracted from full body motion capture data and facial animations using predefined meshes of facial expressions ([1], [2], [3] - JVRC best short paper). We used audio recordings from the RW scenario to synchronize the lip motions with the sound and video recordings to synchronize the motions of the virtual humans and to set up the VE scene.

Initial results

Using our pipeline we captured a routine medical scenario with students [2] and a didactical medical scenario with practitioners [1]. The latter was used for improving the pipeline. The two medical scenarios were further used for generating an interactive online application [1].

Initial conclusion

Our application can be used as an additional tool to medical simulations to give students the possibility to observe and analyze their performance by taking the perspective of their teammates or the patient. Furthermore we intend to gather feedback from medical professionals and students for the usability of the interface of the application.

References

1.Alexandrova IV , Rall M , Breidt M , Kloos U , Tullius G , Bülthoff HH and Mohler BJ (2011) Enhancing Medical Communication Training Using Motion Capture,

Perspective Taking and Virtual Reality, 19th MMVR, (to appear Feb. 2011).

2.Alexandrova IV , Rall M , Breidt M , Kloos U , Tullius G , Bülthoff HH and Mohler BJ (2011) Animations of Medical Training Scenarios in Immersive Virtual Environments, 24th CASA 2011, 1-4.

3.Alexandrova IV , Volkova EP , Kloos U , Bülthoff HH and Mohler BJ (2010) Virtual Storyteller in Immersive Virtual Environments Using Fairy Tales Annotated for Emotion States, JVRC 2010, 65-68.(Best short paper award)

4. Alexandrova IV , Teneva PT , de la Rosa S , Kloos U , Bülthoff HH and Mohler BJ (2010) Egocentric distance judgments in a large screen display immersive virtual environment, 7th APGV 2010, ACM Press, New York, NY, USA, 57-60.

Other project in which I was involved as a research assistant:

• The EU-sponsored project "POETICON" (with Christian Wallraven, as a local coordinator), in which I have modeled the 3D models and helped editing some motion capture data used in the kitchen scenarios.
• Face Project of Isabelle Bülthoff. I have helped setting up the virtual humans used for the experiment and I have modeled the room in which the virtual humans are located.
• Ekaterina Volkova's experiment for emotion perception with an amateur actor. I have helped animating a virtual character with the amateur actors’ motions.

IVELINA VESSELINOVA ALEXANDROVA

Webpage with interactive application: http://cyberneum.de/Medical/index.html

Space perception in real-time virtual environments; Body perception in real-time virtual environments; Real-time simulations, training, therapy and rehabilitation; modeling of realistic real-time virtual environments; generating realistically animated virtual humans in real-time virtual environments.

M. Sc, 2011 Reutlingen University

Media and Communication Informatics

Thesis title: “Generating Virtual Humans Using Predefined Bodily and Facial Emotions in Real-Time Immersive Virtual Environments”

B.A., 2006 Eberhard Karls University Tübingen

Computational Linguistics

Thesis title: “LTAG Semantics for Relative Clause”

High School Diploma, 2003 “Academician Kiril Popov” High School of Mathematics, Plovdiv, Bulgaria

Major: Physics, English, Computer Technologies and Programming

Conference papers (Peer Reviewed)

Alexandrova I.V., Rall M., Breidt M., Kloos U., Tullius G., Bülthoff H. H. and Mohler B.J.: Enhancing Medical Communication Training Using Motion Capture, Perspective Taking and Virtual Reality, 19th Medicine Meets Virtual Reality (MMVR), 2012 (accepted).

Alexandrova I. V., Rall M., Kloos U., Tullius G., Bülthoff H. H. and Mohler B. J.: Animations of Medical Training Scenarios in Immersive Virtual Environments. In: CASA 2011, 24th Annual Conference on Computer Animation and Social Agents, May 2011.

Alexandrova I. V., Volkova E. P., Kloos U., Bülthoff H. H. and Mohler B. J.: Virtual Storyteller in Immersive Virtual Environments Using Fairy Tales Annotated for Emotion States. In: JVRC 2010, 2010 Joint Virtual Reality Conference of EuroVR - EGVE - VEC, Eurographics Association, Goslar, Germany 1-4, September 2010.

Alexandrova I. V., Teneva P. T., de la Rosa S., Kloos U., Bülthoff H. H. and Mohler B. J.: Egocentric Distance Judgments in a Large Screen Display Immersive Virtual Environment. In: APGV 2010, 7th Symposium on Applied Perception in Graphics and Visualization, ACM Press, New York, NY, USA 57-60, July 2010.

Conference papers (Non Peer Reviewed)

Alexandrova I. V.: Egozentrische Entfernungsschätzungen in virtuellen immersiven Umgebungen mit unterschiedlicher Beleuchtung. Informatics Inside: Mensch.Maschine.Immersion. Informatik Konferenz an der Hochschule Reutlingen, May 2010.

Posters (Peer Reviewed)

Volkova E., Mohler B., Linkenauger S., Alexandrova I. and Bülthoff H.H.: Contribution of Prosody in Audio-visual Integration to Emotional Perception of Virtual Characters, 12th International Multisensory Research Forum (IMRF 2011), 12(263), October 2011.

Wallraven C., Schultze M., Mohler B., Volkova E., Alexandrova I., Vatakis A., Pastra K.: Understanding Objects and Actions – A VR Experiment. Poster presented as part of the Joint Virtual Reality Conference (JVRC'10), September 2010.

Volkova E. P., Alexandrova I. V., Bülthoff H. H., Mohler B. J.: Virtual Storytelling of Fairy Tales: Towards Simulation of Emotional Perception of Text. Perception, 39(ECVP Abstract Supplement) 31 p, August 2010.

Alexandrova I. V., Teneva P. T., Kloos U., Bülthoff H. H. and Mohler B. J.: Egocentric Distance Judgments in a Large-Screen Immersive Display Virtual Environment. Perception, 39(ECVP Abstract Supplement) 51 p, August 2010.

Sept. 2010 Best Short Paper Award of the Joint Virtual Reality Conference 2010 of EuroVR - EGVE – VEC for the paper: Virtual Storyteller in Immersive Virtual Environments Using Fairy Tales Annotated for Emotion States.

Oct. 2009 – March 2011 Research Assistant in the Department Perception and Action in Virtual Environments, Max-Planck-Institute for Biological Cybernetics, Tübingen, Germany.

• 3D modeling, motion capture editing, VR programming

July 2009 – Aug. 2009   Practicum in the Department Perception and Action in Virtual Environments, Max-Planck-Institute for Biological Cybernetics, Tübingen, Germany.

• 3D modeling for real-time applications

Febr. 2008 – July 2008   Practicum in the Department (FeP/MOE-CP4), ROBERT BOSCH GMBH, Feuerbach, Germany.

• Planning, developing and supporting the Common Rail High Pressure Pump assembly database as intern websites with the help of HTML, JavaScript, XML and XSLT.

• Installation and tuning of hardware and software.

Oct. 2005 – Febr. 2006   Software Practicum a part of Language Technology for eLearning project (LT4eL), Eberhard Karls University Tübingen, Germany.

• Manually annotate training corpus consisting 150 typical Bulgarian definitions and 50 non-definition sentences.
• Design rules that detect definitions in Bulgarian texts, achieved by the use of Regular Expressions.

Languages: Bulgarian (mother tongue): writing and speaking: fluent.

English: writing and speaking: fluent.

German: writing and speaking: fluent.

Hangeul (Korean): writing and speaking: basic knowledge.

Programming Skills: Java

Computer Skills:Operating Systems: MS Windows, Linux.

Software: Autodesk 3ds Max, Autodesk MotionBuilder, Adobe Photoshop, Poser, 3DVIA Virtools, Xsens MVN, ViconIQ, Vicon Tracker, MS Office.

Markup Languages: HTML, XML( XSLT/XSL/CSS/XSD/DTD).

Script Languages: JavaScript (basic knowledge)

Lighting und rendering

Motion capture editing

Character animation

Character rigging und skinning

3D Modeling, unwrapping und texturing

You can find a .pdf version of my CV here