Defining Preferred and Natural Robot Motions in Immersive Telepresence from a First-Person Perspective

Katherine J Mimnaugh, Markku Suomalainen, Israel Becerra, Eliezer Lozano, Rafael Murrieta, Steven LaValle

Keywords: Human-Robot Interaction, Adaptive Robotic Behavior, Telepresence, Virtual Reality, Robotics, Motion Planning, User Studies

TL;DR: A user study evaluating preferences, comfort, and naturalness of pre-planned mobile robot paths through a virtual museum, viewed by the participants from the perspective of the telepresence robot through a virtual reality head-mounted display.

Abstract: This paper presents some early work and future plans regarding how the autonomous motions of a telepresence robot affect a person embodied in the robot through a head-mounted display. We consider the preferences, comfort, and the perceived naturalness of aspects of piecewise linear paths compared to the same aspects on a smooth path. In a user study, thirty-six subjects (eighteen females) watched panoramic videos of three different paths through a simulated museum in virtual reality and responded to questionnaires regarding each path. We found that comfort had a strong effect on path preference, and that the subjective feeling of naturalness also had a strong effect on path preference, even though people consider different things as natural. We describe a categorization of the responses regarding the naturalness of the robot's motion and provide a recommendation on how this can be applied more broadly. Although immersive robotic telepresence is increasingly being used for remote education, clinical care, and to assist people with disabilities or mobility complications, the full potential of this technology is limited by issues related to user experience. Our work addresses these shortcomings and will enable the future personalization of telepresence experiences for the improvement of overall remote communication and the enhancement of the feeling of presence in a remote location.

Track: extended abstract

Broader Impacts: When attempting to make a robot move "naturally," researchers should take individual variation into account and consider the two dimensions on which it might be perceived. For example, researchers can consider that natural motion in a certain context might not be natural in other contexts, which we found in answers where subjects contrasted how they would move in a museum ("I think in real life I would move similarly to the 3rd path, because it would allow me to view the items better (closer). Also, it simulates the hesitation of a visitor when going in around a museum") versus how they consider themselves to move more generally ("Walking through a corridor in straight line felt more natural than it was in the first path where the movement was from one corner towards another"). Researchers can also consider that the naturalness of parts of the path like the speed and how the turns are executed ("This speed is more natural for a scenario or location such as this. However, the turns were a bit sharp and you feel like you're too close to the objects"), or the whole path that is taken ("It felt most like a path that an actual human would take, getting closer to inspect the paintings"), can each be considered to exhibit naturalness or a lack thereof. All of the individual pieces of a trajectory may be construed as natural or not natural in conflicting ways, so there does not seem to be one universal method to categorize robot motion as natural or not. Therefore, care should be exercised in the third-party classification of the naturalness of robot motion; indeed what a roboticist designing the motion or a reviewer reading the paper might assess as natural may be quite distinct from what a general member of the public may appraise as being natural. Thus the best determination of naturalness is, therefore, attained through the evaluation of research participants.