While Augmented Reality (AR) promises to transform remote collaboration, many aspects remain underexplored, particularly where to place remote avatars in messy, everyday environments. Two mixed-methods within-subjects studies examined avatar placement preferences during cooperative (brainstorming) and competitive (negotiation) tasks between participant pairs, focusing on the influence of physical objects (chairs, box, tree) on user preferences. Results showed a strong preference for frontal or slightly off-centre avatar placements, independent of task type. Participants preferred avatar placements that mirrored real-life behaviour, with chairs inviting placements and the tree deterring them. Notably, the large and visually simple box elicited mixed reactions, being viewed alternately as an obstacle to avoid when placing avatars or as an inviting physical anchor for them, despite causing a clear physicality conflict. We term this the "(Anti-)Affordance Problem", highlighting the complexity of avatar placement within physical contexts, and the necessity for AR collaboration platforms to respond to real-world constraints, offering flexibility in avatar placements to accommodate diverse user preferences.

Touch is a central aspect of social human-human interaction, yet when designing social human-robot interaction, the experience of touch is very often neglected. This work explores whether a robot should feel alive by investigating the effect of life-like haptic stimuli inspired by bio-physiological signals (heartbeat, purring, and thermal feedback) on user perception. The results of an interaction study (n=42) showed that haptic cues which simulate bio-physiological signals significantly increased perceived anthropomorphism, social warmth, and likeability of the PARO robot compared to no additional haptics or abstract vibration. We discuss how multimodal haptic cues, despite increasing perceived eeriness, also increased perceived likeability of the robot, providing novel insights into whether the uncanny valley effect may extend into non-visual modalities. These results provide the first empirical evidence that life-like tactile cues can enhance user perceptions of social robots, offering design guidance for deploying effective and engaging touch interactions between humans and zoomorphic robots.

Augmented reality (AR) applications present virtual elements that are connected to the real world. While these may be aware of a user's geographical or visual context, the real sounds in a user's environment are rarely used in the AR experience. We investigate audio augmented reality (AAR) with sound as the primary output. We present the first evaluation of sonic linking, where an AAR application uses real sounds (bird calls and car engines) in a user's surroundings to drive the interaction. We developed two AAR applications to investigate how to design and use such links: a game where entities are spawned based on real-world sounds and a music player with sound-reactive filtering and volume adjustment. Design variations are compared to cover different AAR scenarios, types of sonic link, and existing unlinked equivalents. The results show that sonic linking can create a more augmented, engaging AAR experience, and may alter a user's relationship with their real-world surroundings, enabling new types of augmented reality applications.

Audio augmented reality (AAR) games allow for audio-only game experiences which blend real and virtual worlds. Despite being sound-based in their output, these games utilise a small number of control schemes, and rarely deploy control schemes that are also sonic in nature. We present the first evaluation of sonic control schemes for AAR gameplay. We present a systematic literature review that collates the control schemes and game scenarios deployed in existing AAR games, and a user study comparing these traditional control schemes with sonic controls -- speech, music, and sonic gesture -- in minigames corresponding to the most common game scenarios. Our results show that while there are some key differences between these control schemes, sonic controls show promise for use in AAR gameplay, and could be deployed in scenarios where AAR developers currently reach for established control schemes.