Online-EYE: Multimodal Implicit Eye Tracking Calibration for XRUnlike other inputs for extended reality (XR) that work out of the box, eye tracking typically requires custom calibration per user or session. We present a multimodal inputs approach for implicit calibration of eye tracker in VR, leveraging UI interaction for continuous, background calibration. Our method analyzes gaze data alongside controller interaction with UI elements, and employing ML techniques it continuously refines the calibration matrix without interrupting users from their current tasks. Potentially eliminating the need for explicit calibration. We demonstrate the accuracy and effectiveness of this implicit approach across various tasks and real time applications achieving comparable eye tracking accuracy to native, explicit calibration. While our evaluation focuses on VR and controller-based interactions, we anticipate the broader applicability of this approach to various XR devices and input modalities.2025BHBaosheng James HOU et al.Google; Lancaster University , Computing and CommunicationsEye Tracking & Gaze InteractionImmersion & Presence ResearchCHI
PinchCatcher: Enabling Multi-selection for Gaze+PinchThis paper investigates multi-selection in XR interfaces based on eye and hand interaction. We propose enabling multi-selection using different variations of techniques that combine gaze with a semi-pinch gesture, allowing users to select multiple objects, while on the way to a full-pinch. While our exploration is based on the semi-pinch mode for activating a quasi-mode, we explore four methods for confirming subselections in multi-selection mode, varying in effort and complexity: dwell-time (SemiDwell), swipe (SemiSwipe), tilt (SemiTilt), and non-dominant hand input (SemiNDH), and compare them to a baseline technique. In the user study, we evaluate their effectiveness in reducing task completion time, errors, and effort. The results indicate the strengths and weaknesses of each technique, with SemiSwipe and SemiDwell as the most preferred methods by participants. We also demonstrate their utility in file managing and RTS gaming application scenarios. This study provides valuable insights to advance 3D input systems in XR.2025JKJinwook Kim et al.KAIST, Graduate School of Culture TechnologyHand Gesture RecognitionEye Tracking & Gaze InteractionMixed Reality WorkspacesCHI
Hands-on, Hands-off: Gaze-Assisted Bimanual 3D InteractionExtended Reality (XR) systems with hand-tracking support direct manipulation of objects with both hands. A common interaction in this context is for the non-dominant hand (NDH) to orient an object for input by the dominant hand (DH). We explore bimanual interaction with gaze through three new modes of interaction where the input of the NDH, DH, or both hands is indirect based on Gaze+Pinch. These modes enable a new dynamic interplay between our hands, allowing flexible alternation between and pairing of complementary operations. Through applications, we demonstrate several use cases in the context of 3D modelling, where users exploit occlusion-free, low-effort, and fluid two-handed manipulation. To gain a deeper understanding of each mode, we present a user study on an asymmetric rotate-translate task. Most participants preferred indirect input with both hands for lower physical effort, without a penalty on user performance. Otherwise, they preferred modes where the NDH oriented the object directly, supporting preshaping of the hand, which is more challenging with indirect gestures. The insights gained are of relevance for the design of XR interfaces that aim to leverage eye and hand input in tandem.2024MLMathias N. Lystbæk et al.Hand Gesture RecognitionEye Tracking & Gaze InteractionMixed Reality WorkspacesUIST
Eye-Hand Movement of Objects in Near Space Extended RealityHand-tracking in Extended Reality (XR) enables moving objects in near space with direct hand gestures, to pick, drag and drop objects in 3D. In this work, we investigate the use of eye-tracking to reduce the effort involved in this interaction. As the eyes naturally look ahead to the target for a drag operation, the principal idea is to map the translation of the object in the image plane to gaze, such that the hand only needs to control the depth component of the operation. We have implemented four techniques that explore two factors: the use of gaze only to move objects in X-Y vs.\ extra refinement by hand, and the use of hand input in the Z axis to directly move objects vs.\ indirectly via a transfer function. We compared all four techniques in a user study (N=24) against baselines of direct and indirect hand input. We detail user performance, effort and experience trade-offs and show that all eye-hand techniques significantly reduce physical effort over direct gestures, pointing toward effortless drag-and-drop for XR environments.2024UWUta Wagner et al.Hand Gesture RecognitionEye Tracking & Gaze InteractionUIST
Spatial Gaze Markers: Supporting Effective Task Switching in Augmented RealityTask switching can occur frequently in daily routines with physical activity. In this paper, we introduce Spatial Gaze Markers, an augmented reality tool to support users in immediately returning to the last point of interest after an attention shift. The tool is task-agnostic, using only eye-tracking information to infer distinct points of visual attention and to mark the corresponding area in the physical environment. We present a user study that evaluates the effectiveness of Spatial Gaze Markers in simulated physical repair and inspection tasks against a no-marker baseline. The results give insights into how Spatial Gaze Markers affect user performance, task load, and experience of users with varying levels of task type and distractions. Our work is relevant to assist physical workers with simple AR techniques and render task switching faster with less effort.2024MLMathias N. Lystbæk et al.Aarhus UniversityEye Tracking & Gaze InteractionAR Navigation & Context AwarenessCHI
Blended Whiteboard: Physicality and Reconfigurability in Remote Mixed Reality CollaborationThe whiteboard is essential for collaborative work. To preserve its physicality in remote collaboration, Mixed Reality (MR) can blend real whiteboards across distributed spaces. Going beyond reality, MR can further enable interactions like panning and zooming in a virtually reconfigurable infinite whiteboard. However, this reconfigurability conflicts with the sense of physicality. To address this tension, we introduce Blended Whiteboard, a remote collaborative MR system enabling reconfigurable surface blending across distributed physical whiteboards. Blended Whiteboard supports a unique collaboration style, where users can sketch on their local whiteboards but also reconfigure the blended space to facilitate transitions between loosely and tightly coupled work. We describe design principles inspired by proxemics; supporting users in changing between facing each other and being side-by-side, and switching between navigating the whiteboard synchronously and independently. Our work shows exciting benefits and challenges of combining physicality and reconfigurability in the design of distributed MR whiteboards.2024JGJens Emil Grønbæk et al.Aarhus University, University of MelbourneMixed Reality WorkspacesDistributed Team CollaborationCHI
Gaze on the Go: Effect of Spatial Reference Frame on Visual Target Acquisition During Physical Locomotion in Extended RealitySpatial interaction relies on fast and accurate visual acquisition. In this work, we analyse how visual acquisition and tracking of targets presented in a head-mounted display is affected by the user moving linearly at walking and jogging paces. We study four reference frames in which targets can be presented: Head and World where targets are affixed relative to the head and environment, respectively; HeadDelay where targets are presented in the head coordinate system but follow head movement with a delay, and novel Path where targets remain at fixed distance in front of the user, in the direction of their movement. Results of our study in virtual reality demonstrate that the more stable the target is relative to the environment, the faster and more precise it can be fixated. The results have practical significance as head-mounted displays enable interaction during mobility, and in particular when eye tracking is considered as input.2024PMPavel Manakhov et al.Aarhus UniversityFull-Body Interaction & Embodied InputEye Tracking & Gaze InteractionAR Navigation & Context AwarenessCHI
Towards Flexible and Robust User Interface Adaptations With Multiple ObjectivesThis paper proposes a new approach for online UI adaptation that aims to overcome the limitations of the most commonly used UI optimization method involving multiple objectives: weighted sum optimization. Weighted sums are highly sensitive to objective formulation, limiting the effectiveness of UI adaptations. We propose ParetoAdapt, an adaptation approach that uses online multi-objective optimization with a posteriori articulated preferences---that is, articulation of preferences after the optimization has concluded to make UI adaptation robust to incomplete and inaccurate objective formulations. It offers users a flexible way to control adaptations by selecting from a set of Pareto optimal adaptation proposals and adjusting them to fit their needs. We showcase the feasibility and flexibility of ParetoAdapt by implementing an online layout adaptation system in a state-of-the-art 3D UI adaptation framework. We further evaluate its robustness and run-time in simulation-based experiments that allow us to systematically change the accuracy of the estimated user preferences. We conclude by discussing how our approach may impact the usability and practicality of online UI adaptations.2023CJChristoph A. Johns et al.Mixed Reality Workspaces360° Video & Panoramic ContentComputational Methods in HCIUIST
A Fitts' Law Study of Gaze-Hand Alignment for Selection in 3D User InterfacesGaze-Hand Alignment has recently been proposed for multimodal selection in 3D. The technique takes advantage of gaze for target pre-selection, as it naturally precedes manual input. Selection is then completed when manual input aligns with gaze on the target, without need for an additional click method. In this work we evaluate two alignment techniques, Gaze&Finger and Gaze&Handray, combining gaze with image plane pointing versus raycasting, in comparison with hands-only baselines and Gaze&Pinch as established multimodal technique. We used Fitts' Law study design with targets presented at different depths in the visual scene, to assess effect of parallax on performance. The alignment techniques outperformed their respective hands-only baselines. Gaze&Finger is efficient when targets are close to the image plane but less performant with increasing target depth due to parallax.2023UWUta Wagner et al.Aarhus UniversityHand Gesture RecognitionEye Tracking & Gaze InteractionCHI
Partially Blended Realities: Aligning Dissimilar Spaces for Distributed Mixed Reality MeetingsMixed Reality allows for distributed meetings where people's local physical spaces are virtually aligned into blended interaction spaces. In many cases, people's physical rooms are dissimilar, making it challenging to design a coherent blended space. We introduce the concept of Partially Blended Realities (PBR) --- using Mixed Reality to support remote collaborators in partially aligning their physical spaces. As physical surfaces are central in collaborative work, PBR supports users in transitioning between different configurations of tables and whiteboard surfaces. In this paper, we 1) describe the design space of PBR, 2) present RealityBlender to explore interaction techniques for how users may configure and transition between blended spaces, and 3) provide insights from a study on how users experience transitions in a remote collaboration task. With this work, we demonstrate new potential for using partial solutions to tackle the alignment problem of dissimilar spaces in distributed Mixed Reality meetings.2023JGJens Emil Sloth Grønbæk et al.Aarhus UniversityMixed Reality WorkspacesDistributed Team CollaborationCHI
AUIT – the Adaptive User Interfaces Toolkit for Designing XR ApplicationsAdaptive user interfaces can improve experiences in Extended Reality (XR) applications by adapting interface elements according to the user's context. Although extensive work explores different adaptation policies, XR creators often struggle with their implementation, which involves laborious manual scripting. The few available tools are underdeveloped for realistic XR settings where it is often necessary to consider conflicting aspects that affect an adaptation. We fill this gap by presenting AUIT, a toolkit that facilitates the design of optimization-based adaptation policies. AUIT allows creators to flexibly combine policies that address common objectives in XR applications, such as element reachability, visibility, and consistency. Instead of using rules or scripts, specifying adaptation policies via adaptation objectives simplifies the design process and enables creative exploration of adaptations. After creators decide which adaptation objectives to use, a multi-objective solver finds appropriate adaptations in real-time. A study showed that AUIT allowed creators of XR applications to quickly and easily create high-quality adaptations.2022JBJoão Marcelo Evangelista Belo et al.AR Navigation & Context AwarenessMixed Reality WorkspacesUIST
"Your Eyes Say You Have Used This Password Before": Identifying Password Reuse from Gaze Behavior and Keystroke DynamicsA significant drawback of text passwords for end-user authentication is password reuse. We propose a novel approach to detect password reuse by leveraging gaze as well as typing behavior and study its accuracy. We collected gaze and typing behavior from 49 users while creating accounts for 1) a webmail client and 2) a news website. While most participants came up with a new password, 32% reported having reused an old password when setting up their accounts. We then compared different ML models to detect password reuse from the collected data. Our models achieve an accuracy of up to 87.7% in detecting password reuse from gaze, 75.8% accuracy from typing, and 88.75% when considering both types of behavior. We demonstrate that \revised{using gaze, password} reuse can already be detected during the registration process, before users entered their password. Our work paves the road for developing novel interventions to prevent password reuse.2022YAYasmeen Abdrabou et al.Bundeswehr University Munich, University of GlasgowEye Tracking & Gaze InteractionPasswords & AuthenticationCHI
Bi-3D: Bi-Manual Pen-and-Touch Interaction for 3D Manipulation on TabletsTablets are attractive for design work anywhere, but 3D manipulations are notoriously difficult. We explore how engaging the stylus and multi-touch in concert can render such tasks easier. We introduce Bi-3D, an interaction concept where touch gestures are combined with 2D pen commands for 3D manipulation. For example, for a fast and intuitive 3D drag & drop technique: the pen drags the object on-screen, and parallel pinch-to-zoom moves it in the third dimension. In this paper, we describe the Bi-3D design space, crossing two-handed input and the degrees-of-freedom (DOF) of 3D manipulation and navigation tasks. We demonstrate sketching and manipulation tools in a prototype 3D design application, where users can fluidly combine 3D operations through alternating and parallel use of the modalities. We evaluate the core technique, bi-manual 3DOF input, against widget and mid-air baselines in an object movement task. We find that Bi-3D is a fast and practical way for multi-dimensional manipulation of graphical objects, promising to facilitate 3D design on stylus and tablet devices.2021KPKen Pfeuffer et al.Force Feedback & Pseudo-Haptic WeightDesktop 3D Printing & Personal FabricationUIST