ProjecTA: A Semi-Humanoid Robotic Teaching Assistant with In-Situ Projection for Guided Tours

TL;DR

ProjecTA is a semi-humanoid robotic teaching assistant that uses in-situ projection to enhance guided tours by reducing cognitive load and improving user engagement compared to traditional screen-based methods.

Contribution

This paper introduces ProjecTA, a novel robotic TA with integrated spatial projection, and provides empirical evidence of its effectiveness in educational settings.

Findings

ProjecTA significantly reduced extraneous cognitive load.

ProjecTA outperformed screen-based TAs in usability and visual usefulness.

Projections and gestures improved understanding and spatial anchoring.

Abstract

Robotic teaching assistants (TAs) often use body-mounted screens to deliver content. In nomadic, walk-and-talk learning, such as tours in makerspaces, these screens can distract learners from real-world objects, increasing extraneous cognitive load. HCI research lacks empirical comparisons of potential alternatives, such as robots with in-situ projection versus screen-based counterparts; little knowledge has been derived for designing such alternatives. We introduce ProjecTA, a semi-humanoid, gesture-capable TA that guides learners while projecting near-object overlays coordinated with speech and gestures. In a mixed-method study (N=24) in a university makerspace, ProjecTA significantly reduced extraneous load and outperformed its screen-based counterpart in perceived usability, usefulness of visual display, and cross-modal complementarity. Qualitative analyses revealed how ProjecTA's coordinated projections, gestures, and speech anchored explanations in place and time, enhancing understanding in ways a screen could not. We derive key design implications for future robotic TAs leveraging spatial projection to support mobile learning in physical environments.