PerspectAR: Addressing Perspective Distortion on Very Large Displays with Adaptive Augmented Reality OverlaysWe present PerspectAR, a novel system addressing perspective distortion on displays caused by large size and wide viewing angles. PerspectAR has three components: a virtual AR screen that curves dynamically according to a user's position relative to the display, a sliding transparent window giving unobstructed access to the physical display in front of the user, and gaze indicators to assist collaborators when they are looking at different renderings. In a within-subjects study in a semi-controlled public environment with 12 pairs, we compared physical display-only and PerspectAR configurations for data analysis tasks. Participants reported less physical workload with PerspectAR and spent more time near the physical display without compromising task performance. Feedback indicates that PerspectAR addressed perspective distortion and provided a contextual view that was useful as a memory aid. Due to the virtual screen curvature, PerspectAR was seen as less effective for tasks involving distance estimates between objects.2025MRMuhammad Raza et al.Dalhousie University, Faculty of Computer ScienceAR Navigation & Context AwarenessVisualization Perception & CognitionCHI
"Bring them back to life": LifeLink Application for Caregivers Dealing with SuicidalitySuicide is a complex phenomenon wherein, in addition to the individual impacted, its effects seep into many lives including those of their caregivers. Caregivers seek help everywhere but face unique challenges including limited access to timely resources and personal mental health struggles. Mobile health apps offer a promising solution, but addressing caregivers’ specific needs remains a concern. We present LifeLink, a persuasive mobile app to support caregivers of individuals experiencing suicidal thoughts. The app was developed in three stages. First, we reviewed 80 existing suicide prevention apps. Second, we designed a low-fidelity prototype of LifeLink using the Persuasive System Design model and refined it through a study conducted with 45 caregivers. Finally, incorporating evidence-based strategies and caregiver feedback, we developed and evaluated LifeLink in another study with 50 caregivers. Results show that LifeLink is user-friendly, engaging, elicits positive user experience and effectively empowers caregivers. LifeLink usage was associated with improved mental wellbeing, increased mental health literacy, and a more supportive environment. Our findings highlight the importance of involving caregivers in the design process. We offer recommendations for designers and researchers developing impactful persuasive technology for suicide prevention and for those working in related areas.2025SJSmriti Jha et al.Dalhousie University, Faculty of Computer ScienceUniversal & Inclusive DesignMental Health Apps & Online Support CommunitiesCHI
Understanding Marine Scientist Software Tool UseMarine science researchers are heavy users of software tools and systems such as statistics packages, visualization tools, and online data catalogues. Following a constructivist grounded theory approach, we conduct a semi-structured interview study of 23 marine science researchers and research supports within a North American university, to understand their perceptions of and approaches towards using both graphical and code-based software tools and systems. We propose the concept of fragmentation to represent how various factors lead to isolated pockets of views and practices concerning software tool use during the research process. These factors include informal learning of tools, preferences towards doing things from scratch, and a push towards more code-based tools. Based on our findings, we suggest design priorities for user interfaces that could more effectively help support marine scientists make and use software tools and systems.2025MLMatthew Lakier et al.University of Waterloo, Cheriton School of Computer ScienceVisualization Perception & CognitionMedical & Scientific Data VisualizationCHI
Virtual Worlds Beyond Sight: Designing and Evaluating an Audio-Haptic System for Non-Visual VR ExplorationContemporary research in Virtual Reality (VR) for users who are visually impaired often employs navigation and interaction modalities that are either non-conventional or constrained by physical spaces or both. We designed and examined a hapto-acoustic VR system that mitigates this by enabling non-visual exploration of large virtual environments using white cane simulation and walk-in place locomotion. The system features a complex urban cityscape incorporating a physical cane prototype coupled with a virtual cane for rendering surface textures and an omnidirectional slide mill for navigation. In addition, spatialized audio is rendered based on the progression of sound through the geometry around the user. A study involving twenty sighted participants evaluated the system through three formative tasks while blindfolded to simulate absolute blindness. 19/20 participants successfully completed all the tasks while effectively navigating through the environment. This work highlights the potential for accessible non-visual VR experiences requiring minimal training and limited prior VR exposure.2025ASAayush Shrestha et al.Dalhousie University, Faculty of Computer ScienceVibrotactile Feedback & Skin StimulationSocial & Collaborative VRVisual Impairment Technologies (Screen Readers, Tactile Graphics, Braille)CHI
Spatial Hand Actions: Exploring the Hand Actions used to Represent Spatial Thinking for 3D Assembling TasksWhen designing 3D objects in 3D virtual environments using naturalistic 3D user interfaces, people use their hands to manipulate the environment and objects inside it. At the same time, people utilize their spatial thinking to understand the spatial relationship of the objects in the scene. Yet, the relationship between spatial thinking and hand actions remains unclear. Here, we present a user study with 18 participants that examines the association between 3D assembling tasks and reflective hand movements that allow people to enhance their spatial thinking. Utilizing a mixed-methods protocol, we identified nine SPATIAL HAND ACTIONS and three SPATIAL THEMES people use when designing 3D objects. Then, we analyzed a subset of the participants to understand the relationship between SPATIAL HAND ACTIONS and spatial abilities. Our results will help develop better hand-based naturalistic 3DUI that considers the spatial thinking abilities of the users.2025PRPrashant Rawat et al.Dalhousie University, Faculty of Computer ScienceHand Gesture RecognitionFull-Body Interaction & Embodied Input3D Modeling & AnimationCHI
ThermalPen: Investigating the Influence of Thermal Haptic Feedback for Creativity in 3D SketchingThis paper presents ThermalPen, a novel device for 3D sketching that utilizes thermal feedback to allow users to feel the materiality of their sketches. The pen lets users draw using six colours and three textures mapped to different temperatures. Our goal is to investigate the influence of thermal feedback on user creativity for 3D sketching. In a user study with 24 participants, we asked them to draw with and without thermal feedback. Our results show that thermal feedback improved user creativity for specific tasks. Qualitative results also indicate an effect on the user experience. Our work contributes to understanding how thermal feedback can increase user satisfaction with 3D sketching and provide insights and directions for future work.2024PHPhilipp Pascal Hoffmann et al.Vibrotactile Feedback & Skin StimulationShape-Changing Interfaces & Soft Robotic MaterialsC&C
An Artists' Perspectives on Natural Interactions for Virtual Reality 3D SketchingVirtual Reality (VR) applications like OpenBrush offer artists access to 3D sketching tools within the digital 3D virtual space. These 3D sketching tools allow users to ``paint'' using virtual digital strokes that emulate real-world mark-making. Yet, users paint these strokes through (unimodal) VR controllers. Given that sketching in VR is a relatively nascent field, this paper investigates ways to expand our understanding of sketching in virtual space, taking full advantage of what an immersive digital canvas offers. Through a study conducted with the participation of artists, we identify potential methods for natural multimodal and unimodal interaction techniques in 3D sketching. These methods demonstrate ways to incrementally improve existing interaction techniques and incorporate artistic feedback into the design.2024RRRichard Rodriguez et al.Colorado State University3D Modeling & AnimationDigital Art Installations & Interactive PerformanceCHI
EyeGuide & EyeConGuide: Gaze-based Visual Guides to Improve 3D Sketching SystemsVisual guides help to align strokes and raise accuracy in Virtual Reality (VR) sketching tools. Automatic guides that appear at relevant sketching areas are convenient to have for a seamless sketching with a guide. We explore guides that exploit eye-tracking to render them adaptive to the user's visual attention. EyeGuide and EyeConGuide cause visual grid fragments to appear spatially close to the user's intended sketches, based on the information of the user's eye-gaze direction and the 3D position of the hand. Here we evaluated the techniques in two user studies across simple and complex sketching objectives in VR. The results show that gaze-based guides have a positive effect on sketching accuracy, perceived usability and preference over manual activation in the tested tasks. Our research contributes to integrating gaze-contingent techniques for assistive guides and presents important insights into multimodal design applications in VR.2024RTRumeysa Turkmen et al.Kadir Has UniversityEye Tracking & Gaze InteractionMixed Reality Workspaces3D Modeling & AnimationCHI
SynthScribe: Deep Multimodal Tools for Synthesizer Sound Retrieval and ExplorationSynthesizers are powerful tools that allow musicians to create dynamic and original sounds. Existing commercial interfaces for synthesizers typically require musicians to interact with complex low-level parameters or to manage large libraries of premade sounds. To address these challenges, we implement SynthScribe --- a fullstack system that uses multimodal deep learning to let users express their intentions at a much higher level. We implement features which address a number of difficulties, namely 1) searching through existing sounds, 2) creating completely new sounds, 3) making small but meaningful modifications to a given sound. This is achieved with three main features: a multimodal search engine for a large library of synthesizer sounds; a user centered genetic algorithm by which completely new sounds can be created and selected given the users preferences; a sound editing support feature which highlights and gives examples for key control parameters with respect to a text or audio based query. The results of our user studies show SynthScribe is capable of reliably retrieving and modifying sounds while also affording the ability to create completely new sounds that expand a musicians creative horizon.2024SBStephen Brade et al.Generative AI (Text, Image, Music, Video)Music Composition & Sound Design ToolsCreative Collaboration & Feedback SystemsIUI
Promptify: Text-to-Image Generation through Interactive Prompt Exploration with Large Language ModelsText-to-image generative models have demonstrated remarkable capabilities in generating high-quality images based on textual prompts. However, crafting prompts that accurately capture the user's creative intent remains challenging. It often involves laborious trial-and-error procedures to ensure that the model interprets the prompts in alignment with the user's intention. To address these challenges, we present Promptify, an interactive system that supports prompt exploration and refinement for text-to-image generative models. Promptify utilizes a suggestion engine powered by large language models to help users quickly explore and craft diverse prompts. Our interface allows users to organize the generated images flexibly, and based on their preferences, Promptify suggests potential changes to the original prompt. This feedback loop enables users to iteratively refine their prompts and enhance desired features while avoiding unwanted ones. Our user study shows that Promptify effectively facilitates the text-to-image workflow, allowing users to create visually appealing images on their first attempt while requiring significantly less cognitive load than a widely-used baseline tool.2023SBStephen Brade et al.Generative AI (Text, Image, Music, Video)Human-LLM CollaborationAI-Assisted Creative WritingUIST
Are You Human? Investigating the Perceptions and Evaluations of Virtual Versus Human Instagram InfluencersVirtual influencers (VI) are on the rise on Instagram, and companies increasingly cooperate with them for marketing campaigns. This has motivated an increasing number of studies, which investigate our perceptions of these influencers. Most studies propose that VI are often rated lower in perceived trust and higher in uncanniness. Yet, we still lack a deeper understanding as to why this is the case. We conduct 2 studies: 1) a questionnaire with 150 participants to get the general perception for the included influencers, and 2) an electroencephalography (EEG) study to get insights into the underlying neural mechanisms of influencer perception. Our results support findings from related works regarding lower trust and higher uncanniness associated with VI. Interestingly, the EEG components N400 and LPP did not modulate perceived trust, but rather perceived humanness, uncanniness, and intentions to follow recommendations. This provides a fruitful beginning for future research on virtual humans.2023ANAnika Nissen et al.Institute for Computer Science and Business Information SystemsAgent Personality & AnthropomorphismAI Ethics, Fairness & AccountabilityOnline Identity & Self-PresentationCHI
Tailoring a Persuasive Game to Promote Secure Smartphone BehaviourThe use of smartphones has become an integral part of everyone’s lives. Due to the ubiquitous nature and multiple functionalities of smartphones, the data handled by these devices are sensitive in nature. Despite the measures companies take to protect users’ data, research has shown that people do not take the necessary actions to stay safe from security and privacy threats. Persuasive games have been implemented across various domains to motivate people towards a positive behaviour change. Even though persuasive games could be effective, research has shown that the one-size-fits-all approach to designing persuasive games might not be as effective as the tailored versions of the game. This paper presents the design and evaluation of a persuasive game to improve user awareness about smartphone security and privacy tailored to the user’s motivational orientation using Regulatory Focus Theory. From the results of our mixed-methods in-the-wild study of 102 people followed by a one-on-one interview of 25 people, it is evident that the tailored version of the persuasive game performed better than the non-tailored version of the game towards improving users’ secure smartphone behaviour. We contribute to the broader HCI community by offering design suggestions and the benefits of tailoring persuasive games.2023AGAnirudh Ganesh et al.Dalhousie UniversitySerious & Functional GamesGamification DesignPrivacy by Design & User ControlCHI
Para Cima y Pa’ Abajo: Building Bridges Between HCI Research in Latin America and in the Global NorthThe Human-computer Interaction (HCI) community has the opportunity to foster the integration of research practices across the Global South and North to begin overcoming colonial relationships. In this paper, we focus on the case of Latin America (LATAM), where initiatives to increase the representation of HCI practitioners lack a consolidated understanding of the practices they employ, the factors that influence them, and the challenges that practitioners face. To address this knowledge gap, we employ a mixed-methods approach, comprising a survey (66 respondents) and in-depth interviews (19 interviewees). Our analyses characterize a set of research perspectives on how HCI is practiced in/about LATAM; a set of driving forces and tensions with a heavy reliance on diasporic dynamics; and a set of professional demands and associated structural limitations. We also offer a roadmap towards building connections across HCI communities, in an attempt to rebuild HCI as a pluriverse.2023PRPedro Reynolds-Cuéllar et al.MITInclusive DesignDeveloping Countries & HCI for Development (HCI4D)CHI
Tailoring Persuasive and Behaviour Change Systems Based on Stages of Change and MotivationPersuasive systems are effective at motivating behaviour change using various persuasive strategies. Research shows that tailoring these systems increases their effectiveness. However, there is little knowledge on how PS can be tailored to people’s Stages of Change (SoC). We conduct a large-scale study of 568 participants to investigate how individuals at different SoC respond to various strategies. We also explore why the strategies motivate behaviour change using the ARCS motivation model. Our results show that people’s SoC plays a significant role in the perceived persuasiveness of different strategies and that the strategies motivate for different reasons. For instance, people at the precontemplation stage tend to be strongly motivated by self-monitoring strategy because it raises their consciousness or self-awareness. Our work is the first to link research on the theory of SoC with the theory of motivation and Persuasive Systems Design (PSD) model to develop practical guidelines to inform the tailoring of persuasive systems.2021OOOladapo Oyebode et al.Dalhousie UniversityAI-Assisted Decision-Making & AutomationUniversal & Inclusive DesignCHI
A Comparative Evaluation of Techniques for Sharing AR Experiences in MuseumsMuseums are constantly searching for new ways to increase engagement with their exhibits, from electronic guides to modern digital technologies such as special-purpose tablets, smartphones, and virtual and augmented reality (AR). For AR exhibits in particular, promoting shared experience and group cohesion is not straightforward. In this work, we investigate scenarios in which not everyone is using a head-worn display (HWD), either because there aren't enough available or simply because someone might feel uncomfortable using it. We propose two sharing techniques for AR experiences and evaluate them in a long term in-the-wild study: Over-the-Shoulder AR, which renders a real-time virtual representation of the augmented reality content on a large secondary display; Semantic Linking, which displays contextual information about the virtual content on the same large display. We also introduce a complementary technique: Indicator Rings, which display the locations of the HWD user's objects-of-focus. We observed that participants in the Over-the-Shoulder AR and Semantic Linking conditions stayed together and exhibited more verbal exchanges than participants in a Baseline condition, which could indicate that they were more engaged. Self-reported measures indicated an increase in pair communication and increased comprehension of the virtual content for participants without the HWD. Participants without the HWD also displayed a greater understanding of the location of virtual elements with support from the Indicator Rings, and used them as a tool to guide the HWD user through the virtual content. We discuss design implications for interactive augmented reality exhibits and possible applications outside the cultural heritage scenario.2019JFJuliano Franz et al.Art and performanceCSCW
MP Remix: Relaxed WYSIWIS Immersive Interfaces for Mixed Presence Collaboration With 3D ContentMixed Reality (MR) can be used for mixed presence collaboration by connecting physical and virtual worlds to create an integrated space. We consider an MR configuration in which collocated collaborators work around a tabletop display, while remote collaborators wear an HMD to interact with a connected virtual environment that gives a 3D perspective, and consider the impact of varying degrees of view congruence with their collaborators. In a within-subjects study with 18 groups of 3, groups completed task scenarios involving 3D object manipulation around a physical-virtual mapped tabletop. We compare a synchronized Tabletop display baseline and two MR conditions with different levels of view congruence: Fishtank and Hover. Fishtank has a high degree of congruence as it shares a top-down perspective of the 3D objects with the tabletop collaborators. The Hover condition has less view congruence since 3D content hovers front of the remote collaborator above the table. The MR conditions yielded higher self-reported awareness and co-presence than the Tabletop condition for both collocated and remote participants. Remote collaborators significantly preferred the MR conditions for manipulating shared 3D models and communicating with their collaborators. Our findings illustrate strengths and weaknesses of both MR techniques but show that more participants preferred the less-congruent Hover condition overall. Reasons include that it facilitated interaction and viewing 3D objects.2019MSMohamad Hossein Salimian et al.VR and immersive interfacesCSCW
Improving The Efficacy Of Games for Change Using Personalization ModelsThere has been a continuous increase in the design and application of computer games for purposes other than entertainment in recent years. Serious games—games that motivate behaviour and retain attention in serious contexts — can change the attitudes, behaviours, and habits of players. These games for change have been shown to motivate behaviour change, persuade people, and promote learning using various persuasive strategies. However, persuasive strategies that motivate one player may demotivate another. In this article, we show the importance of tailoring games for change in the context of a game designed to improve healthy eating habits. We tailored a custom-designed game by adapting only the persuasive strategies employed; the game mechanics themselves did not vary. Tailoring the game design to players’ personality type improved the effectiveness of the games in promoting positive attitudes, intention to change behaviour, and self-efficacy. Furthermore, we show that the benefits of tailoring the game intervention are not explained by the improved player experience, but directly by the choice of persuasive strategy employed. Designers and researchers of games for change can use our results to improve the efficacy of their game-based interventions.2018RORita Orji et al.Dalhousie UniversitySerious & Functional GamesGamification DesignCHI
Personalizing Persuasive Strategies in Gameful Systems to Gamification User TypesPersuasive gameful systems are effective tools for motivating behaviour change. Research has shown that tailoring these systems to individuals can increase their efficacy; however, there is little knowledge on how to personalize them. We conducted a large-scale study of 543 participants to investigate how different gamification user types responded to ten persuasive strategies depicted in storyboards representing persuasive gameful health systems. Our results reveal that people’s gamification user types play significant roles in the perceived persuasiveness of different strategies. People scoring high in the ‘player’ user type tend to be motivated by competition, comparison, cooperation, and reward while ‘disruptors’ are likely to be demotivated by punishment, goal-setting, simulation, and self-monitoring. ‘Socialisers’ could be motivated using any of the strategies; they are the most responsive to persuasion overall. Finally, we contribute to CHI research and practice by offering design guidelines for tailoring persuasive gameful systems to each gamification user type.2018RORita Orji et al.Dalhousie UniversitySerious & Functional GamesGamification DesignCHI