REVITALISE viRtual skIlls TrAining for pubLIc
SpEaking

Magalie Ochs, Ristorcelli Marion, D Ambra, Vessiot Manon, Rémy Casanova,
Jean-Marie Pergandi

► To cite this version:

Magalie Ochs, Ristorcelli Marion, D Ambra, Vessiot Manon, Rémy Casanova, et al. REVITALISE viRtual skIlls TrAining for pubLIc SpEaking. Intelligent Virtual Agent, Sep 2024, Glasgow, United Kingdom. 10.1145/nnnnnnn.nnnnnnn. hal-05387146

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# REVITALISE

## viRtual bEhaVioral skIlls TrAining for pubLlc SpEaking

OCHS Magalie

Aix Marseille Univ, CNRS, LIS
Marseille, France
magalie.ochs@lis-lab.fr

RISTORCELLI Marion

Aix Marseille Univ, CNRS, LIS
Marseille, France
marion.ristorcelli@lis-lab.fr

D'AMBRA Alexandre

Aix Marseille Univ, CNRS, ISM
Marseille, France
alexandre.D-AMBRA@univ-amu.fr

VESSIOT Manon

Aix Marseille Univ, CNRS, ISM
Marseille, France
manon.VESSIOT@univ-amu.fr

CASANOVA Rémy

Aix Marseille Univ, CNRS, ISM
Marseille, France
remy.casanova@univ-amu.fr

PERGANDI Jean-Marie

Aix Marseille Univ, CNRS, ISM
Marseille, France
jean-marie.pergandi@univ-amu.fr

## ABSTRACT

In this article, we present a new tool called REVITALISE (viRtual bEhaVioral skIlls TrAining for pubLlc SpEaking) which enables the user to practice public speaking in front of a virtual audience in virtual reality. The tool is specially designed to simulate different virtual audiences to vary the user experiences. The virtual environments as well as the genders of the virtual characters and their non-verbal behaviors can be easily set-up in REVITALISE. Moreover, the motion capture-based animations, validated through a perceptive studies, enable to simulate and combine different social attitudes of the virtual audience.

## KEYWORDS

Virtual audience, training tool, social attitudes, virtual reality

## ACM Reference Format:

OCHS Magalie, RISTORCELLI Marion, D'AMBRA Alexandre, VESSIOT Manon, CASANOVA Rémy, and PERGANDI Jean-Marie. 2024. REVITALISE viRtual bEhaVioral skIlls TrAining for pubLlc SpEaking. In *Proceedings of Intelligent Virtual Agent Conference (IVA'24)*. ACM, New York, NY, USA, 3 pages. https://doi.org/10.1145/nnnnnnn.nnnnnnn

For some years now, Virtual Reality (VR) has emerged as a key tool for social skills training, and more particularly for public speaking training. They integrate virtual environments, inspired by real-life situations (classroom, conference room), and are composed of virtual characters playing the role of spectators [4, 10, 15]. In virtual reality public speaking training system, the virtual audience is particularly important [8]. The virtual audience may convey different social attitudes, such as interest or boredom [10], through their behavior (e.g. facial expressions, head movements, posture and gaze direction) and these simulated social attitudes have a strong impact on the user's perceived difficulty in speaking in public [19, 22].

In this paper, we describe a new tool called REVITALISE (viRtual bEhaVioral skIlls TrAining for pubLlc SpEaking) which enables users to practice public speaking in front of a virtual audience in Virtual Reality (VR). The tool is specially designed to simulate different virtual audiences to vary the user experiences. In Section 3, the virtual environments as well as the genders of the virtual characters can be easily set-up. Moreover, in Section 4, the motion capture-based animations, validated through a perceptive studies, enable to simulate and combine different social attitudes of the virtual audience.

## 1 INTRODUCTION

Nowadays, public speaking is a primordial social skill in our daily life both professionally and personally [12]. Whether at a job interview, looking for an internship or giving an oral presentation to a medium or large audience, speakers need to follow certain rules to make a good presentation [1], but they also have to adapt to the audience's behavior in order to maintain their attention and interest [7, 16, 17]. These competencies are not innate. This exercise requires a lot of preparation and training. However, we have relatively few tools for rehearsing public speaking in a context close to the reality [9].

## 2 RELATED WORKS

In the literature, different public speaking training tool including a virtual audience has been proposed with different levels of control (e.g. manually, scripted, automatically adapted to the user) [2, 3, 11, 18, 20]). In the REVITALISE tool presented in this paper, we focus on scripted behaviors of the virtual audience. This choice is motivated by the fact that we aimed at controlling precisely the behavior of the virtual audience.

In the existing speaking training systems, the virtual audiences differ. The number of virtual agents composing the virtual audience varies from a few number (from 3 to 10 [11, 18, 20]) to a large group of virtual agents (from 15 to 100 [13, 14, 23]). Regarding gender, some of the existing virtual audiences consider only male virtual agents [6, 20], others consider few females agents in their virtual audience [14, 18] and finally, few research considers a mixed number of male and female virtual agents [11]. As far as we know, no existing tool enables one to define the number of virtual characters in the audience as well as the proportion of female and male virtual characters while these elements may have a strong impact on the user's experience as shown in [20, 22]. In existing training systems,

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<footnote>IVA'24, September 16-19, 2024, Glasgow, UK</footnote>

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we find a wide variety of nonverbal behavior for a virtual audience. In general, the researchers use gaze direction, body posture, head movements and facial expressions to allow virtual agents to express several social attitudes as a real audience would [5, 11, 20]. In the REVITALISE tool, we have defined libraries of behavioral animations to simulate different social attitudes based on a perceptive studies in VR [21] (Section 4).

## 3 VIRTUAL AUDIENCE ENVIRONMENTS

The objective of the REVITALISE tool is to provide several public speaking virtual environments. Different elements of the environment can be set-up before the training. Indeed, a user interface allows to choose between *two environments: a meeting room* or an *amphitheatre* (Figure 1). Moreover, before starting the simulation,

<figure><img src="image_2.png" /><figcaption>**Figure 1:** Screenshot of the virtual environments (amphitheatre on the top, meeting room on the bottom)</figcaption></figure>

an interface enables one to define the number of virtual characters in the audience as well as the percentage of male and female characters.

## 4 VIRTUAL CHARACTERS' BEHAVIORAL ANIMATIONS

In order to simulate smooth and realistic virtual character's behaviors, the animations were built on the basis of motion capture of a woman and a man. Indeed, two people played a wide range of behaviors that were collected using the Xsens motion capture system (Figure 2). The animations have been integrated in Unity using IClone and Character Creator.

As described in [21], we have conducted a perceptive study to evaluate the animations. This experiment has enabled us to validate the believability of the animations as well as to associate positive and negative emotional and epistemic stances to animations. In order to simulate different social attitudes on the virtual characters of the audience, in Unity, we have defined scriptable objects, to easily set-up social behaviors libraries (Figure 3). One can define libraries of behaviors for each different social attitude; for instance, a library of behavior conveying a positive attitude and one with behaviors that convey a negative attitude. For each social attitude,

<figure><img src="image_3.png" /><figcaption>**Figure 2:** Motion capture of a human listener's behavior</figcaption></figure>

<figure><img src="image_4.png" /><figcaption>**Figure 3:** Set-up of the social behaviors libraries</figcaption></figure>

a percentage of the number of characters who will play the animations from the associated library is defined. Then, for each library, a scriptable object allows to characterize all the non-verbal behaviors associated to the social attitude for each modality: arm position (fist under the chin, arms Crossed, hands on thigh), head movements (nod, shake, tilt, no movement), torso position (forward, backwards, straight), facial expression (smile, frown, doubt, no Expression) and gaze direction (look at the speaker, look away from the speaker). Another possibility is to choose from a set of predefined behaviors, such as a virtual character simulating a phone call or whispering to its neighbor. Note that we have predefined a positive and negative social attitudes libraries based on the perceptive studies described in [21].

## 5 CONCLUSION AND PERSPECTIVES

In this paper, we have presented a virtual reality public speaking training tool. A particular attention in the design of the tool has been paid to the virtual audience. The animations have been created based on motion capture to provide smooth and realistic behaviors of the virtual characters. Validated through a perceptive studies, the animations enable one to simulate different social attitudes. Moreover, the tool offers the possibility to easily set-up new social behavior libraries. We are currently working on the integration of modules to automatically record the user's verbal and non-verbal behavior in order to provide feedback on her/his performance at the end of the simulation.
# ACKNOWLEDGMENTS

This research was funded under the ANR REVITALISE grant ANR-21-CE33-0016-02.

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# 6 ONLINE RESOURCES

A video presentation of the REVITALISE tool: https://www.youtube.com/watch?v=bF9FfSJOYG0