Using Socially Expressive Mixed Reality Arms for Enhancing Low-Expressivity Robots

TL;DR

This study demonstrates that adding virtual, socially expressive arms via mixed reality significantly enhances perceived emotion, presence, and social interaction qualities of low-expressivity robots in a human-robot interaction task.

Contribution

The paper introduces a novel approach of augmenting low-expressivity robots with virtual arms in mixed reality to improve social expressiveness and interaction quality.

Findings

Virtual arms increased perceived emotion and helpfulness.

Users distinguished gesture valence and intent accurately.

Enhanced physical and social presence improved user attitudes.

Abstract

Expressivity--the use of multiple modalities to convey internal state and intent of a robot--is critical for interaction. Yet, due to cost, safety, and other constraints, many robots lack high degrees of physical expressivity. This paper explores using mixed reality to enhance a robot with limited expressivity by adding virtual arms that extend the robot's expressiveness. The arms, capable of a range of non-physically-constrained gestures, were evaluated in a between-subject study ($n=34$) where participants engaged in a mixed reality mathematics task with a socially assistive robot. The study results indicate that the virtual arms added a higher degree of perceived emotion, helpfulness, and physical presence to the robot. Users who reported a higher perceived physical presence also found the robot to have a higher degree of social presence, ease of use, usefulness, and had a positive attitude toward using the robot with mixed reality. The results also demonstrate the users' ability to distinguish the virtual gestures' valence and intent.