by Marc Fabri
Fabri, M. (2006) Emotionally Expressive Avatars for Collaborative Virtual Environments, PhD Thesis, Leeds Metropolitan University, November 2006
When humans communicate with each other face-to-face, they frequently use their bodies to complement, contradict,... more
When humans communicate with each other face-to-face, they frequently use their bodies to complement, contradict, substitute, or regulate what is being said. These non-verbal signals are important for understanding each other, particularly in respect of expressing changing moods and emotional states. In modern communication technologies such as telephone, email or instant messaging, these indicators are typically lost and communication is limited to the exchange of verbal messages, with little scope for expressing emotions.
This thesis explores Collaborative Virtual Environments (CVEs) as an alternative communication technology potentially allowing interlocutors to express themselves emotionally in an efficient and effective way. CVE users are represented by three-dimensional, animated embodiments, referred to as “avatars”, capable of showing emotional expressions. The avatar acts as an interaction device, providing information that would otherwise be difficult to mediate. Potential applications for such CVE systems are all areas where people cannot come together physically, but wish to discuss or collaborate on certain matters, for example in distance learning, home working, or simply to chat with friends and colleagues. Further, CVEs could be used in the therapeutic intervention of phobias and help address social impairments such as autism.
To investigate how emotions can efficiently and effectively be visualised in a CVE, an animated virtual head was designed to express, in a readily recognisable manner, the six universal emotions happiness, sadness, anger, fear, surprise and disgust. A controlled experiment was then conducted to investigate the virtual head model. Effectiveness was demonstrated through good recognition rates for most emotions, and efficiency was established since a reduced animation feature set was found to be sufficient to build core distinctive facial expressions. A set of exemplar facial expressions and guidelines for their use was developed.
A second controlled experiment was then conducted to investigate the effect such an emotionally expressive, animated avatar has on users of a prototype CVE, the Virtual Messenger (VM). The hypothesis was that introducing emotions into CVE interaction can be beneficial on many levels, namely the users’ subjective experience, their involvement, and how they perceive and interact with each other. The design considerations for VM are outlined, and a newly developed methodological framework for evaluation is presented.
The findings suggest that emotional expressiveness in avatars increases involvement in the interaction between CVE users, as well as their sense of being together, or copresence. This has a positive effect on their subjective experience. Further, empathy was identified as a key component for creating a more enjoyable experience and greater harmony between CVE users. The caveat is that emotionally expressive avatars may not be useful in all contexts or all types of CVEs as they may distract users from the task they are aiming to complete.
Finally, a set of tentative design guidelines for emotionally expressive avatars in CVEs is derived from the work undertaken, covering the appearance and expressive abilities of avatars. These are aimed at CVE researchers and avatar designers.
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![](http://photos.academia.edu/337116/202023/393785/tiny_mariafelicia.de_laurentis.jpg?1326314467 "<strong>Mariafelicia De Laurentis</strong><br/>University of Naples "Federico II""){kind=small}
