Head-mounted displays (HMDs) increase immersion into virtual worlds. The problem is that this limits headset users’ awareness of bystanders: headset users cannot attend to bystanders’ presence and activities. We call this HMD boundary. We explore how to make the HMD boundary permeable by comparing different ways of providing informal awareness cues to the headset user about bystanders. We adapted and implemented three visualization techniques (Avatar View, Radar and Presence++) that share bystanders’ location and orientation with headset users. We conducted a hybrid user and simulation study with three different types of VR content (high, medium, low interactively) with twenty participants to compare how these visualization techniques allow people to maintain an awareness of bystanders, and how they affect immersion (compared to a baseline condition). Our study reveals that a see-through avatar representation of bystanders was effective, but led to slightly reduced immersion in the VR content. Based on our findings, we discuss how future awareness visualization techniques can be designed to mitigate the reduction of immersion for the headset user.

Board games allow us to share collective entertainment experiences. They entertain because of the interactions between players, physical manipulation of tokens and decision making. Unfortunately, most board games exclude people with visual impairments as they were not initially designed for players with special needs. Through a user-centered design process with an accessible game library and visually impaired players, we observed challenges and solutions in making existing board games accessible through handcrafted solutions (tactile stickers, braille labels, etc.). In a second step, we used Spatial Augmented Reality, to make existing board games inclusive by adding interactivity (GameARt). In a case study with an existing board game considered as not accessible (Jamaica), we designed an interactive SAR version with touch detection (JamaicAR). We evaluated this prototype in a user study with 5 groups of 3 players each, including sighted, low vision and blind players. All players, independent of visual status, were able to play the Augmented Reality game. Moreover, the game was rated positively by all players regarding attractiveness, play engrossment, enjoyment and social connectivity. Our work shows that spatial augmented reality has the potential to make board games accessible to people with visual impairments when handcrafted adaptations fall short.

We propose a style of hand postures to trigger commands on a laptop. The key idea is to perform hand-postures while keeping the hands on, beside, or below the keyboard, to align with natural laptop usage. 36 hand-posture variations are explored considering three resting locations, left or right hand, open or closed hand, and three wrist rotation angles. A 30-participant formative study measures posture preferences and generates a dataset of nearly 350K images under different lighting conditions and backgrounds. A deep learning recognizer achieves over 97% accuracy when classifying all 36 postures with 2 additional non-posture classes for typing and non-typing. A second experiment with 20 participants validates the recognizer under real-time usage and compares posture invocation time with keyboard shortcuts. Results find low error rates and fast formation time, indicating postures are close to current typing and pointing postures. Finally, practical use case demonstrations are presented, and further extensions discussed.

Tangible controls---especially sliders and rotary knobs---have been explored in a wide range of interactive applications for desktop and immersive environments. Studies have shown that they support greater precision and provide proprioceptive benefits, such as support for eyes-free interaction. However, such controls tend to be expressly designed for specific applications. We draw inspiration from a bespoke controller for immersive data visualisation, but decompose this design into a simple, wireless, composable unit featuring two actuated sliders and a rotary encoder. Through these controller units, we explore the interaction opportunities around actuated sliders; supporting precise selection, infinite scrolling, adaptive data representations, and rich haptic feedback; all within a mode-less interaction space. We demonstrate the controllers' use for simple, ad hoc desktop interaction, before moving on to more complex, multi-dimensional interactions in VR and AR. We show that the flexibility and composability of these actuated controllers provides an emergent design space for interaction.

Picking numbers is arguably the most frequently performed input task on smartwatches. This paper presents three new methods for picking numbers on smartwatches by performing directional swipes, twisting the wrist, and varying contact force on the screen. Unlike the default number picker, the proposed methods enable users to actively switch between slow-and-steady and fast-and-continuous increments and decrements during the input process. We evaluated these methods in two user studies. The first compared the new methods with the default input stepper method in both stationary and mobile settings. The second compared them for individual numeric values and values embedded in text. In both studies, swipe yielded a significantly faster input rate. Participants also found the method faster, more accurate, and the least mentally and physically demanding compared to the other methods. Accuracy rates were comparable between the methods.