GazeNoter: Co-Piloted AR Note-Taking via Gaze Selection of LLM Suggestions to Match Users' IntentionsNote-taking is critical during speeches and discussions, serving for later summarization and organization and for real-time question and opinion reminding in question-and-answer sessions or timely contributions in discussions. Manually typing on smartphones for note-taking could be distracting and increase cognitive load. While LLMs are used to automatically generate summaries and highlights, the content generated by AI may not match users’ intentions without user input. Therefore, we propose an AI-copiloted AR system, GazeNoter, to allow users to swiftly select diverse LLM-generated suggestions via gaze on an AR headset for real-time note-taking. GazeNoter leverages an AR headset as a medium for users to swiftly adjust the LLM output to match their intentions, forming a user-in-the-loop AI system for both within-context and beyond-context notes. We conducted two studies to verify the usability of GazeNoter in attending speeches in a static sitting condition and walking meetings and discussions in a mobile walking condition, respectively.2025HTHsin-Ruey Tsai et al.National Chengchi UniversityEye Tracking & Gaze InteractionMixed Reality WorkspacesHuman-LLM CollaborationCHI
Toward Understanding the Impact of Visualized Focus Levels in Virtual Reality on User Presence and ExperienceNeurofeedback refers to the process of feeding a sensory representation of brain activity back to users in real time to improve a particular brain function, e.g., their focus and/or attention on a particular task. This study addressed the notable lack of research on methods used to visualize EEG data and their effects on the immersive quality of VR. We developed an algorithm to quantify focus, yielding a focus score. A pre-study with twenty participants confirmed its effectiveness in distinguishing between focused and relaxed mental states. Subsequently, we used this focus score to prototype a VR experience system visualizing the focus score in preconfigured manners, which was utilized in an exploratory study to assess the impact of different neurofeedback visualization methods on user engagement and focus in VR. Among all the visualization methods evaluated, the environmental scheme stood out due to its superior usability during task execution, its ability to evoke positive emotions through the visualization of objects or scenes, and its minimal deviation from user expectations. Additionally, we explored design guidelines based on collected results for future research to further refine the visualization scheme, ensuring effective integration of the focus score within the VR environment. These enhancements are crucial for designing neurofeedback visualization schemes that aim to boost participant focus in VR settings, offering significant insights into the optimization of such technologies.2024CYChuang-Wen You et al.Brain-Computer Interface (BCI) & NeurofeedbackImmersion & Presence ResearchMobileHCI
transPAF: Rendering Omnidirectional Impact Feedback with Dynamic Point of Application of Force All Round a ControllerImpact is common feedback on virtual reality (VR) controllers. It applies to different points of application of force (PAFs) and directions in varied scenarios, e.g., using a sword and pickaxe, stabbing and slashing with a sword, or balls flying and hitting a racket in different directions. Therefore, rendering dynamic PAF and force direction is essential. We propose transPAF to render omnidirectional impact feedback with dynamic PAF all round the controller. transPAF consists of a controller, semicircular track, linear track, and impactor, which are all rotatable. The impactor can move to any position in a sphere around the controller and rotate in any direction. Therefore, dynamic PAF and force direction are achieved and independent to each other. We conducted a just-noticeable difference (JND) study to understand users’ distinguishability in position and direction, separately, and a VR study to verify that the feedback with dynamic PAF and force direction enhances VR realism.2023HCHong-Xian Chen et al.National Chengchi UniversityForce Feedback & Pseudo-Haptic WeightCHI
Awe Versus Aww: The Effectiveness of Two Kinds of Positive Emotional Stimulation on Stress Reduction for Online Content ModeratorsWhen people have the freedom to create and post content on the internet, particularly anonymously, they do not always respect the rules and regulations of the websites on which they post, leaving other unsuspecting users vulnerable to sexism, racism, threats, and other unacceptable content in their daily cyberspace diet. However, content moderators witness the worst of humanity on a daily basis in place of the average netizen. This takes its toll on moderators, causing stress, fatigue, and emotional distress akin to the symptomology of post-traumatic stress disorder (PTSD). The goal of the present study was to explore whether adding positive stimuli to breaktimes–-images of baby animals or beautiful, aweinspiring landscapes–-could help reduce the negative side-effects of being a content moderator. To test this, we had over 300 experienced content moderators read and decide whether 200 fake text-based social media posts were acceptable or not for public consumption. Although we set out to test positive emotional stimulation, however, we actually found that it is the cumulative nature of the negative emotions that likely negates most of the effects of the intervention: the longer the person had practiced content moderation, the stronger their negative experience. Connections to compassion fatigue and how best to spend work breaks as a content moderator are discussed.2022CCChristine L Cook et al.Platform Moderation; Platform ModerationCSCW
ELAXO : Rendering Versatile Resistive Force Feedback for Fingers Grasping and TwistingHaptic feedback not only enhances immersion in virtual reality (VR) but also delivers experts’ haptic sensation tips in VR training, e.g., properly clamping a tenon and mortise joint or tightening a screw in the assembly of VR factory training, which could even improve the training performance. However, various and complicated manipulation is in different scenarios. Although haptic feedback of virtual objects’ shape, stiffness or resistive force in pressing or grasping is achieved by previous research, rotational resistive force when twisting or turning virtual objects is seldom discussed or explored, especially for a wearable device. Therefore, we propose a wearable device, ELAXO, to integrate continuous resistive force and continuous rotational resistive force with or without resilience in grasping and twisting, respectively. ELAXO is an exoskeleton with rings, mechanical brakes and elastic bands. The brakes achieve shape rendering and switch between with and without resilience modes for the resistive force. The detachable and rotatable rings and elastic bands render continuous resistive force in grasping and twisting. We conducted a just noticeable difference (JND) study to understand users’ distinguishability in the four conditions, resistive force and rotational resistive force with and without resilience, separately. A VR study was then performed to verify that the versatile resistive force feedback from ELAXO enhances the VR experiences.2022ZZZhong-Yi Zhang et al.Force Feedback & Pseudo-Haptic WeightFull-Body Interaction & Embodied InputUIST
FingerX: Rendering Haptic Shape of Virtual Objects Augmented from Real Objects using Extendable and Withdrawable Supports on FingersInteracting with not only virtual but also real objects, or even virtual objects augmented by real objects becomes a trend of virtual reality (VR) interactions and is common in augmented reality (AR). However, current haptic shape rendering devices generally focus on feedback of virtual objects, and require the users to put down or take off those devices to perceive real objects. Therefore, we propose FingerX to render haptic shapes and enable users to touch, grasp and interact with virtual and real objects simultaneously. An extender on the fingertip extends to a corresponding height to support between the fingertip and the real objects or the hand, to render virtual shapes. A ring rotates and withdraws the extender behind the fingertip when touching real objects. By independently controlling four extenders and rings on each finger with the exception of the pinky finger, FingerX renders feedback in three common scenarios, including touching virtual objects augmented by real environments (e.g., a desk), grasping virtual objects augmented by real objects (e.g., a bottle) and grasping virtual objects in the hand. We conducted a shape recognition study to evaluate the recognition rates for these three scenarios and obtained an average recognition rate of 76.59% with shape visual feedback. We then performed a VR study to observe how users interact with virtual and real objects simultaneously and verify that FingerX significantly enhances VR realism, compared to current vibrotactile methods.2022HTLynn Tsai et al.National Chengchi UniversityVibrotactile Feedback & Skin StimulationForce Feedback & Pseudo-Haptic WeightHand Gesture RecognitionCHI
ImpactVest: Rendering Spatio-Temporal Multilevel Impact Force Feedback on Body in VRRendering instant and intense impact feedback on users’ hands, limbs and head to enhance realism in virtual reality (VR) has been proposed in previous works, but impact on the body is still less discussed. With the body’s large surface area to utilize, numerous impact patterns can be rendered in versatile VR applications,e.g., being shot, blasted, punched or slashed on body in VR games. Herein we propose ImpactVest to render spatio-temporal multilevel impact force feedback on body. By independently controlling nine impactors in a 3×3 layout using elastic force, impact is generated at different levels, positions and time sequences for versatile spatial and temporal combinations. We conducted a just-noticeable difference (JND) study to understand users’ impact level distinguishability on the body. A time interval threshold study was then performed to ascertain what time interval thresholds between two impact stimuli should be used to distinguish from simultaneous impact, a continuous impact stroke and two discrete impact stimuli. Based on the results, we conducted a VR experience study to verify that impact feedback from ImpactVest enhances VR realism.2022HTHsin-Ruey Tsai et al.National Chengchi UniversityVibrotactile Feedback & Skin StimulationImmersion & Presence ResearchCHI
HairTouch: Providing Stiffness, Roughness and Surface Height Differences Using Reconfigurable Brush Hairs on a VR ControllerTactile feedback is widely used to enhance realism in virtual reality (VR). When touching virtual objects, stiffness and roughness are common and obvious factors perceived by the users. Furthermore, when touching a surface with complicated surface structure, differences from not only stiffness and roughness but also surface height are crucial. To integrate these factors, we propose a pin-based handheld device, HairTouch, to provide stiffness differences, roughness differences, surface height differences and their combinations. HairTouch consists of two pins for the two finger segments close to the index fingertip, respectively. By controlling brush hairs' length and bending direction to change the hairs' elasticity and hair tip direction, each pin renders various stiffness and roughness, respectively. By further independently controlling the hairs' configuration and pins' height, versatile stiffness, roughness and surface height differences are achieved. We conducted a perception study to realize users' distinguishability of stiffness and roughness on each of the segments. Based on the results, we performed a VR experience study to verify that the tactile feedback from HairTouch enhances VR realism.2021CLChi-Jung Lee et al.National Taiwan UniversityMid-Air Haptics (Ultrasonic)Haptic WearablesImmersion & Presence ResearchCHI
A Chinese-Language Validation of the Video Game Demand Scale (VGDS-C): Measuring the Cognitive, Emotional, Physical, and Social Demands of Video GamesVideo games are engaging multimedia experiences that require players’ cognitive, emotional, physical (in terms of controllers and exertion), and social faculties. Recent theorizing has suggested that these dimensions of demand can explain processes by which players engage with and respond to gameplay. A relatively new measure—the five-factor, 26-item Video Game Demand Scale (VGDS)—has been tested for dimensionality and measurement validity with English- and German-speaking players, but not for other play populations. Given the popularity of video games among Chinese-speaking players, this brief report demonstrates a successful translation of VGDS into Traditional Chinese (VGDS-C). A sample of N = 863 Chinese speakers in Taiwan were asked to recall and describe a recent gaming experience before completing the VGDS-C along with other gaming-related measures (tests of construct validity). VGDS-C was shown to be a reliable and valid way of assessing players’ perceptions of the myriad demands of video gaming.2021NBNicholas David Bowman et al.Texas Tech University, National Chengchi UniversityGame UX & Player BehaviorRole-Playing & Narrative GamesCHI
GuideBand: Intuitive 3D Multilevel Force Guidance on a Wristband in Virtual RealityFor haptic guidance, vibrotactile feedback is a commonly-used mechanism, but requires users to interpret its complicated patterns especially in 3D guidance, which is not intuitive and increases their mental effort. Furthermore, for haptic guidance in virtual reality (VR), not only guidance performance but also realism should be considered. Since vibrotactile feedback interferes with and reduces VR realism, it may not be proper for VR haptic guidance. Therefore, we propose a wearable device, GuideBand, to provide intuitive 3D multilevel force guidance upon the forearm, which reproduces an effect that the forearm is pulled and guided by a virtual guider or telepresent person in VR. GuideBand uses three motors to pull a wristband at different force levels in 3D space. Such feedback usually requires much larger and heavier robotic arms or exoskeletons. We conducted a just-noticeable difference study to understand users’ force level distinguishability. Based on the results, we performed a study to verify that compared with state-of-the-art vibrotactile guidance, GuideBand is more intuitive, needs a lower level of mental effort, and achieves similar guidance performance. We further conducted a VR experience study to observe how users combine and complement visual and force guidance, and prove that GuideBand enhances realism in VR guidance.2021HTHsin-Ruey Tsai et al.National Chengchi UniversityForce Feedback & Pseudo-Haptic WeightFull-Body Interaction & Embodied InputFoot & Wrist InteractionCHI
ElastiLinks: Force Feedback between VR Controllers with Dynamic Points of Application of ForceForce feedback is commonly used to enhance realism in virtual reality (VR). However, current works mainly focus on providing different force types or patterns, but do not investigate how a proper point of application of force (PAF), which means where the resultant force is applied to, affects users’ experience. For example, users perceive resistive force without torque when pulling a virtual bow, but with torque when pulling a virtual slingshot. Therefore, we propose a set of handheld controllers, ElastiLinks, to provide force feedback between controllers with dynamic PAFs. A rotatable track on each controller provides a dynamic PAF, and two common types of force feedback, resistive force and impact, are produced by two links, respectively. We performed a force perception study to ascertain users’ resistive and impact force level distinguishability between controllers. Based on the results, we conducted another perception study to understand users’ distinguishability of PAF offset and rotation differences. Finally, we performed a VR experience study to prove that force feedback with dynamic PAFs enhances VR experience.2020TWTzu-Yun Wei et al.Force Feedback & Pseudo-Haptic WeightFull-Body Interaction & Embodied InputImmersion & Presence ResearchUIST
WalkingVibe: Reducing Virtual Reality Sickness and Improving Realism while Walking in VR using Unobtrusive Head-mounted Vibrotactile FeedbackVirtual Reality (VR) sickness is common with symptoms such as headaches, nausea, and disorientation, and is a major barrier to using VR. We propose WalkingVibe, which applies unobtrusive vibrotactile feedback for VR walking experiences, and also reduces VR sickness and discomfort while improving realism. Feedback is delivered through two small vibration motors behind the ears at a frequency that strikes a balance in inducing vestibular response while minimizing annoyance. We conducted a 240-person study to explore how visual, audio, and various tactile feedback designs affect the locomotion experience of users walking passively in VR while seated statically in reality. Results showed timing and location for tactile feedback have significant effects on VR sickness and realism. With WalkingVibe, 2-sided step-synchronized design significantly reduces VR sickness and discomfort while significantly improving realism. Furthermore, its unobtrusiveness and ease of integration make WalkingVibe a practical approach for improving VR experiences with new and existing VR headsets.2020YPYi-Hao Peng et al.National Taiwan UniversityVibrotactile Feedback & Skin StimulationImmersion & Presence ResearchCHI
ElastOscillation: 3D Multilevel Force Feedback for Damped Oscillation on VR ControllersForce feedback from damped oscillation is a common effect in our daily lives, especially when shaking an elastic object, an object hanging or containing other stuff, or a container with liquid, e.g., casting with a fishing pole or wine-swirling. Such a force, affected by complex physical variations and collisions, is difficult to properly simulate using current force feedback methods. Therefore, we propose ElastOscillation on a virtual reality (VR) controller to provide 3D multilevel force feedback for damped oscillation to enhance VR experiences. ElastOscillation consists of a proxy, six elastic bands and DC motors. It leverages the motors to control the bands' elasticity to restrain the movement of the proxy, which is connected with the bands. Therefore, when users shake the ElastOscillation device, the proxy shakes or moves in corresponding ranges of movement. The users then perceive the force from oscillation at different levels. In addition, elastic force from the bands further reinforces the oscillation force feedback. We conducted a force perception study to understand users' distinguishability for perceiving oscillation forces in 1D and 2D movement, respectively. Based on the results, we performed a VR experience study to show that the force feedback provided by ElastOscillation enhances VR realism.2020HTHsin-Ruey Tsai et al.National Chengchi UniversityForce Feedback & Pseudo-Haptic WeightCHI
Does Who Matter? Studying the Impact of Relationship Characteristics on Receptivity to Mobile IM MessagesThis study examines the characteristics of mobile instant-messaging users' relationships with their social contacts and the effects of both relationship and interruption context on four measures of receptivity: Attentiveness, Responsiveness, Interruptibility, and Opportuneness. Overall, interruption context overshadows relationship characteristics as predictors of all four of these facets of receptivity; this overshadowing was most acute for Interruptibility and Opportuneness, but existed for all factors. In addition, while Mobile Maintenance Expectation and Activity Engagement were negatively correlated with all receptivity measures, each such measure had its own set of predictors, highlighting the conceptual differences among the measures. Finally, delving more deeply into potential relationship effects, we found that a single, simple closeness question was as effective at predicting receptivity as the 12-item Unidimensional Relationship Closeness Scale.2019HLHao-Ping Lee et al.National Chiao Tung UniversityNotification & Interruption ManagementCHI