Effects of Coupling in Human-Virtual Agent Body Interaction

TL;DR

This study investigates how the dynamic coupling between users and virtual agents affects engagement, co-presence, and believability during body interaction, using an experimental theatrical game with varying agent autonomy.

Contribution

It introduces an experimental framework to measure the impact of different levels of virtual agent autonomy on human-agent body interaction and related subjective experiences.

Findings

Higher agent autonomy increases user engagement.

Coupling correlates with perceived co-presence and believability.

Experimental results support hypotheses on interaction dynamics.

Abstract

This paper presents a study of the dynamic coupling between a user and a virtual character during body interaction. Coupling is directly linked with other dimensions, such as co-presence, engagement, and believability, and was measured in an experiment that allowed users to describe their subjective feelings about those dimensions of interest. The experiment was based on a theatrical game involving the imitation of slow upper-body movements and the proposal of new movements by the user and virtual agent. The agent's behaviour varied in autonomy: the agent could limit itself to imitating the user's movements only, initiate new movements, or combine both behaviours. After the game, each participant completed a questionnaire regarding their engagement in the interaction, their subjective feeling about the co-presence of the agent, etc. Based on four main dimensions of interest, we tested several hypotheses against our experimental results, which are discussed here.