As VR expands into public spaces, new challenges emerge around spontaneous interactions between bystanders and unfamiliar VR users. While current VR systems often prioritize user awareness of their physical surroundings, they overlook the social dynamics affecting nearby bystanders. We conducted a deception-based study (N=80) examining how interface availability influences bystanders’ comfort, confidence, and hesitation when interrupting VR users. We compared traditional static interruption interfaces (e.g., button on screen) with a proactive proxy that actively approached bystanders upon detecting interruption intent. Static interfaces, due to insufficient cueing, frequently caused bystander discomfort, leading to hesitant physical interruptions or complete communication avoidance. In contrast, the proactive proxy implicitly conveyed social permission, significantly enhancing bystanders’ comfort and confidence. Our findings provide empirical insights into how bystanders assess availability and initiate interruptions with unfamiliar VR users in shared spaces, offering design implications for VR systems that support bystander agency and comfort during these interactions.

Voice assistants have afforded users rich interaction opportunities to access information and issue commands in a variety of contexts. However, some users feel uneasy or creeped out by voice assistants, leading to a decreased desire to use them. As there has yet to be a comprehensive understanding of the factors that cause users to perceive voice assistants as being creepy, this research developed an empirical scale to measure the creepiness inherent in various voice assistants. Utilizing prior scale creation methodologies, a 7-item Perceived Creepiness of Voice Assistants Scale (PCAS) was created and validated. The scale measures how creepy a new voice assistant would be for users of voice assistants. The scale was developed to ensure that researchers and designers can evaluate the next generation of voice assistants before such voice assistants are released to the wider public.

Gestural interaction has evolved from a set of novel interaction techniques developed in research labs, to a dominant interaction modality used by millions of users everyday. Despite its widespread adoption, the design of appropriate gesture vocabularies remains a challenging task for developers and designers. Existing research has largely used Expert-Led, User-Led, or Computationally-Based methodologies to design gesture vocabularies. These methodologies leverage the expertise, experience, and capabilities of experts, users, and systems to fulfill different requirements. In practice, however, none of these methodologies provide designers with a complete, multi-faceted perspective of the many factors that influence the design of gesture vocabularies, largely because a singular set of factors has yet to be established. Additionally, these methodologies do not identify or emphasize the subset of factors that are crucial to consider when designing for a given use case. Therefore, this work reports on the findings from an exhaustive literature review that identified 13 factors crucial to gesture vocabulary design and examines the evaluation methods and interaction techniques commonly associated with each factor. The identified factors also enable a holistic examination of existing gesture design methodologies from a factor-oriented viewpoint and highlighting the strengths and weaknesses of each methodology. This work closes with proposals of future research directions of developing an iterative user-centered and factor-centric gesture design approach as well as establishing an evolving ecosystem of factors that are crucial to gesture design.

The decreased cost and increased usability of personal fabrication technologies has enabled a new generation of crafters to integrate digital designs and computationally created artifacts into physically-based practices. With the simultaneous ubiquity of e-commerce and social networking channels, these technologies have enabled many crafters to transform their hobbies into home-based businesses. To understand the opportunities and challenges that fusing social networking platforms, personal fabrication equipment, and e-commerce have afforded these homepreneurs, an online survey and follow-up interviews were conducted with crafters who use hobbyist cutting plotters to personalize and sell goods online. The findings uncovered an emerging group of homepreneurs, i.e., mompreneurs, who use these technologies for supplemental income for their families and highlighted the emotional and opportunistic benefits that such personalized, at-home manufacturing affords. They also highlighted the workflows and lifestyle implications of using these technologies to run home-based businesses, the multi-faceted usage and dependence these homepreneurs have on online social platforms such as Facebook, the complex software toolchains that are used, and the commonplace practice of appropriating designs from others that occurs in this community.

Prior research identified that physical paper documents have many positive attributes, for example natural tangibility and inherent physical flexibility. When documents are presented on digital devices, however, they can provide unique functionality to users, such as the ability to search, view dynamic multimedia content, and make use of indexing. This work explores the fusion of physical and digital paper documents. It first presents the results of a study that probed how users perform document-intensive analytical tasks when both physical and digital versions of documents were available. The study findings then informed the design of HoloDoc, a mixed reality system that augments physical artifacts with rich interaction and dynamic virtual content. Finally, we present the interaction techniques that HoloDoc affords, and the results of a second study that assessed HoloDoc's utility when working with digital and physical copies of academic articles.

Globalization has led to the destruction of many cultural practices, expressions, and knowledge found within local communities. These practices, defined by UNESCO as Intangible Cultural Heritage (ICH), have been identified, promoted, and safeguarded by nations, academia, organizations and local communities to varying degrees. Despite such efforts, many practices are still in danger of being lost or forgotten forever. With the increased popularity of livestreaming in China, some streamers have begun to use livestreaming to showcase and promote ICH activities. To better understand the practices, opportunities, and challenges inherent in sharing and safeguarding ICH through livestreaming, we interviewed 10 streamers and 8 viewers from China. Through our qualitative investigation, we found that ICH streamers had altruistic motivations and engaged with viewers using multiple modalities beyond livestreams. We also found that livestreaming encouraged real-time interaction and sociality, while non-live curated videos attracted attention from a broader audience and assisted in the archiving of knowledge.

Prior research has demonstrated that users are increasingly employing multiple devices during daily work. Currently, devices such as keyboards, cell phones, and tablets remain largely unaware of their role within a user's workflow. As a result, transitioning between devices is tedious, often to the degree that users are discouraged from taking full advantage of the devices they have within reach. This work explores the device ecologies used in desk-centric environments and complies the insights observed into SMAC, a simplified model of attention and capture that emphasizes the role of user-device proxemics, as mediated by hand placement, gaze, and relative body orientation, as well as inter-device proxemics. SMAC illustrates the potential of harnessing the rich, proxemic diversity that exists between users and their device ecologies, while also helping to organize and synthesize the growing body of literature on distributed user interfaces. An evaluation study using SMAC demonstrated that users could easily understand the tenants of user- and inter-device proxemics and found them to be valuable within their workflows.

The livestreaming industry in China is gaining greater traction than its European and North American counterparts and has a profound impact on the stakeholders' online and offline lives. An emerging genre of livestreaming that has become increasingly popular in China is outdoor livestreaming. With outdoor livestreams, streamers broadcast outdoor activities, travel, or socialize with passersby in outdoor settings, often for 6 or more hours, and viewers watch such streams for hours each day. However, given that professionally produced content about travel and outdoor activities are not very popular, it is currently unknown what makes this category of livestreams so engaging and how these techniques can be applied to other content or genres. Thus, we conducted a mixed methods study consisting of a survey (N=287) and interviews (N = 20) to understand how viewers watch and engage with outdoor livestreams in China. The data revealed that outdoor livestreams encompass many categories of content, environments and passersby behaviors create challenges and uncertainty for viewers and streamers, and viewers watch livestreams for surprising lengths of time (e.g., sometimes more than 5 continuous hours). We also gained insights into how live commenting and virtual gifting encourage engagement. Lastly, we detail how the behaviors of dedicated fans and casual viewers differ and provide implications for the design of livestreaming services that support outdoor activities.

Growing interest in personal fabrication has resulted in many ways to ideate, design, and prototype, in addition to studies of who a maker is and the challenges they face. Less attention, however, has focused on the role of the environment in fabrication processes. By understanding how interactions with tools, fixtures, materials, and spaces shape workflows, we can better determine how to design the next generation of workshops, design tools, and fabrication equipment to support personal fabrication activities. To build this understanding, site visits and interviews at local makerspaces, fabrication studios, and workshops were conducted. These visits uncovered the rich practices and roadblocks generated by workshops today. The observations identified the importance of spatial layouts, territoriality and occupant agency, distributed knowledge, and organizational flux, among others, to design and fabrication processes. These observations were further synthesized into one possible direction for such spaces: hybrid workshops (i.e., environments that can leverage computation and responsive architecture to enhance a maker's ability to design and fabricate). This work identifies how such spaces could harness the rich practices and eliminate the challenges found with workshops today and discusses the technical innovations and philosophical questions that hybrid workshops will pose to the future of personal fabrication.

Prewriting is the process of generating and organizing ideas before drafting a document. Although often overlooked by novice writers and writing tool developers, prewriting is a critical process that improves the quality of a final document. To better understand current prewriting practices, we first conducted interviews with writing learners and experts. Based on the learners' needs and experts' recommendations, we then designed and developed InkPlanner, a novel pen and touch visualization tool that allows writers to utilize visual diagramming for ideation during prewriting. InkPlanner further allows writers to sort their ideas into a logical and sequential narrative by using a novel widget - NarrativeLine. Using a NarrativeLine, InkPlanner can automatically generate a document outline to guide later drafting exercises. Inkplanner is powered by machine-generated semantic and structural suggestions that are curated from various texts. To qualitatively review the tool and understand how writers use InkPlanner for prewriting, two writing experts were interviewed and a user study was conducted with university students. The results demonstrated that InkPlanner encouraged writers to generate more diverse ideas and also enabled them to think more strategically about how to organize their ideas for later drafting.

When fabricating, it is common to follow a prescribed set of steps in a tutorial or how-to. While popular, such explicit knowledge resources have many inconsistencies and omissions, use static illustrations, and cannot adapt to drop-in makers or a maker's mistakes. To overcome many of these issues, this work presents Automatics, a novel explicit knowledge resource system that dynamically generates fabrication activities for one or more makers based on their current environmental and fabrication context. Automatics assigns tasks to makers based on the past tools and components the maker was working with, enables makers to recover from mistakes through model regeneration, suggests alternative tools if a needed tool is unavailable or in use, and allows multiple makers to drop-in throughout a fabrication activity. Initial usage and feedback from novice makers showed that Automatics increases the number of tasks that can be completed compared to paper instructions, decreases frustration, and improves one's understanding of the global context of assigned tasks during fabrication activities.

Smart rings have a unique form factor suitable for many applications, however, they offer little opportunity to provide the user with natural output. We propose passive kinesthetic force feedback as a novel output method for rotational input on smart rings. With this new output channel, friction force profiles can be designed, programmed, and felt by a user when they rotate the ring. This modality enables new interactions for ring form factors. We demonstrate the potential of this new haptic output method though Frictio, a prototype smart ring. In a controlled experiment, we determined the recognizability of six force profiles, including Hard Stop, Ramp-Up, Ramp-Down, Resistant Force, Bump, and No Force. The results showed that participants could distinguish between the force profiles with 94% accuracy. We conclude by presenting a set of novel interaction techniques that Frictio enables, and discuss insights and directions for future research.

Within this work, a novel metaphor, haunted design, is explored to challenge the definitions of "display" used today. Haunted design draws inspiration and vision from some of the most multi-modal and sensory diverse experiences that have been reported, the paranormal and hauntings. By synthesizing and deconstructing such phenomena, four novel opportunities to direct display design were uncovered, e.g., intensity, familiarly, tangibility, and shareability. A large-scale design probe, The Living Room, guided the ideation and prototyping of design concepts that exemplify facets of haunted design. By combining the opportunities, design concepts, and survey responses, a framework highlighting the importance of objects, their behavior, and the resulting phenomena to haunted design was developed. Given its emphasis on the odd and unusual, the haunted design metaphor should great spur conversation and alternative directions for future display-based user experiences.

In this work, we explore moveables, i.e., interactive papercraft that harness user interaction to generate visual effects. First, we present a survey of children's books that captured the state of the art of moveables. The results of this survey were synthesized into a moveable taxonomy and informed MoveableMaker, a new tool to assist users in designing, generating, and assembling moveable papercraft. MoveableMaker supports the creation and customization of a number of moveable effects and employs moveable-specific features including animated tooltips, automatic instruction generation, constraint-based rendering, techniques to reduce material waste, and so on. To understand how MoveableMaker encourages creativity and enhances the workflow when creating moveables, a series of exploratory workshops were conducted. The results of these explorations, including the content participants created and their impressions, are discussed, along with avenues for future research involving moveables.

While pen computing has become increasingly more popular, device responsiveness, or latency, still plagues such interaction. Although there have been advances in digitizer technology over the last few years, commercial end-to-end latencies are unfortunately similar to those found with touchscreens, i.e., 65 - 120 milliseconds. We report on a prototype stylus-enabled device, the High Performance Stylus System (HPSS), designed to display latencies as low as one millisecond while users ink or perform dragging tasks.

The user experience on tablets that support both touch and styli is less than ideal, due in large part to the problem of unintended touch or palm rejection . Devices are often unable to distinguish between intended touch (i.e., interaction on the screen intended for action) and unintended touch (i.e., incidental interaction from the palm, forearm, or fingers). This often results in stray ink strokes and accidental navigation, frustrating users. We present a data collection experiment where participants performed inking tasks, and where natural tablet and stylus behaviors were observed and analyzed from both digitizer and behavioral perspectives. An analysis and comparison of novel and existing unintended touch algorithms revealed that the use of stylus information can greatly reduce unintended touch. Our analysis also revealed many natural stylus behaviors that influence unintended touch, underscoring the importance of application and ecosystem demands, and providing many avenues for future research and technological advancement.

This work examines intermanual gesture transfer, i.e., learning a gesture with one hand and performing it with the other. Using a traditional retention and transfer paradigm from the motor learning literature, participants learned four gestures on a touchscreen. The study found that touchscreen gestures transfer, and do so symmetrically. Regardless of the hand used during training, gestures were performed with a comparable level of error and speed by the untrained hand, even after 24 hours. In addition, the form of a gesture, i.e., its length or curvature, was found to have no influence on transferability. These results have important implications for the design of stroke-based gestural interfaces: acquisition could occur with either hand and it is possible to interchange the hand used to perform gestures. The work concludes with a discussion of these implications and highlights how they can be applied to gesture learning and current gestural systems.

We present Medusa, a proximity-aware multi-touch tabletop. Medusa uses 138 inexpensive proximity sensors to: detect a user's presence and location, determine body and arm locations, distinguish between the right and left arms, and map touch point to specific users and specific hands. Our tracking algorithms and hardware designs are described. Exploring this unique design, we develop and report on a collection of interactions enabled by Medusa in support of multi-user collaborative design, specifically within the context of Proxi-Sketch, a multi-user UI prototyping tool. We discuss design issues, system implementation, limitations, and generalizable concepts throughout the paper.

People with a wide spectrum of disabilities, ranging from spinal injuries to autism, have benefited from equine assisted therapy (EAT). Using EAT, therapy patients have improved both physically and psychologically (e.g., demonstrating increased attention, motivation, and communication skills). There are still many open questions regarding this therapy and the reasons for its success. Many of these questions have remained unanswered due in large part to the uncontrolled nature of EAT. The Virtual Equine Assisted Therapy (VEAT) Project integrates a robotic platform with virtual reality technologies to provide a safe, controlled environment through which various aspects of EAT can be isolated and studied. The system incorporates realistic equine motions with visual, auditory, olfactory, and somatosensory stimuli to provide highly immersive experiences to patients.