Unbounded: Object-Boundary Interaction in Mixed Reality

Abstract

Boundaries such as walls, windows, and doors are ubiquitous in the physical world, yet their potential in mixed reality (MR) remains underexplored. We present Unbounded, a Research through Design inquiry into object--boundary interaction (OBI). Building on prior work, we articulate a design space aimed at providing a shared language for OBI. To demonstrate its potential, we design and implement eight examples across productivity and art exploration scenarios, showcasing how OBIs can enrich and reframe everyday interactions. We further engage with six MR experts in one-on-one feedback sessions, using the design space and examples as design probes. Their reflections broaden the conceptual scope of OBI, reveal new possibilities for how the framework may be applied, and highlight implications for future MR interaction design. https://www.zhuoyuelyu.com/unbounded

Figures (8)

• Figure 1: Initial iterations of the design space (a--d; details in \ref{['sec:iterations']}). Part (d) shows the resulting space, defined in \ref{['sec:dimensions']} and its illustration explained in \ref{['sec:language']}. Through expert feedback sessions (\ref{['sec:expert-sessions']}), we refined (d) and present the final version in \ref{['fig:final-design-space']}. The iterations shown here remain unchanged to document the RtD process.
• Figure 2: Ten existing OBIs described using our framework. Each includes an interaction scene and description, with its illustration using our visual design language (\ref{['sec:language']}). For example, the first illustration depicts a Physical object performing a Crossing through a Physical, Transformative boundary, with Unilateral perception, Opaque visibility, and Indirect manipulation.
• Figure 3: Procedure for each one-on-one expert feedback session. The semi-structured interview questions we used are provided in the supplementary material.
• Figure 4: Three linked abstraction levels illustrated by P1 (using Opaque as an example) to help designers utilize the design space elements. We adopted this structure across the final space (\ref{['fig:final-design-space']}).
• Figure 5: Final design space refined through expert feedback. Following \ref{['sec:situating-abstraction']}, each element is presented at three abstraction levels. \ref{['sec:reimagining-boundaries']} informs boundary affordances, as well as the inclusion of Invisible, Deformable, and Formation. \ref{['sec:reframing-human']} introduces Participation. To reflect \ref{['sec:beyond-visible-ephemeral']}, we expanded Dynamic to include Spatial, Temporal, and Environmental, and recategorized movement patterns. Speech and Gaze were added based on \ref{['sec:toward-deeper-connections']}. \ref{['sec:design-practice-that-resonates', 'sec:how-to-use']} guide usage.