Abstract Dynamic touch requires the perceptual system to extract stable material properties from complex, evolving signals. We show that the tactile system relies on total spectral energy, the overall vibratory power of contact-induced transients, rather than waveform details or dominant frequency. Using a spectral energy compensation method, we conducted five psychophysical experiments in two degraded feedback scenarios: soft finger interfaces, where fingertip stiffness was reduced by an inflatable silicone bubble, and soft surface interactions, where participants tapped compliant foam surfaces. In both, participants reliably discriminated hardness and identified materials only when natural spectral energy profiles were preserved, independent of signal type. Judgments scaled systematically with energy level, and under conflicting cues, spectral energy dominated over frequency or compliance. These findings establish spectral energy as a governing cue in tactile perception, revealing a simple and robust computation akin to estimating mechanical work. This principle offers a generalizable framework for restoring touch in prosthetics, teleoperation, and immersive virtual environments. Teaser Total spectral energy - not frequency - is the behaviorally relevant feature driving material perception through dynamic touch.

This study examines how users' tactile preferences in fidgeting devices relate to attention during task performance. We developed a custom fidget cube with six keyboard-style switches (two clicky, two tactile, two linear) that varied in resistance and “clickiness”. In Phase 1, participants completed a Stroop test without fidgeting and while fidgeting with a mixed-button cube. Interaction logs from the mixed-button cube identified each participant's most and least preferred button types. In Phase 2, participants repeated the Stroop test while fidgeting with two single-button cubes-one containing only their most preferred button and one containing only their least preferred button. Participants were significantly less accurate when fidgeting with the mixed-button cube than when not fidgeting or when fidgeting with the single-button versions. They also showed faster reaction times when fidgeting with their preferred single-button cube compared to the mixed-button cube. Overall, the primary effect was a consistency benefit: restricting interaction to a single tactile signature improved accuracy, reaction time, and error rates relative to the mixed-button condition. These findings underscore the value of designing fidget and haptic feedback systems that minimize competing tactile cues in attention-critical contexts, and they suggest practical directions for therapeutic, educational, and workplace applications.

Both haptic signals and simple, non-anthropomorphic robots can convey complex emotions and enhance remote communication. In this study, we integrated a zoomorphic socially expressive Blossom robot and a haptic sleeve to create a novel multimodal telepresence platform for remote social interaction. Through a within-subject user study with 16 participants, we explored the individual and combined effects of socially expressive robots and mediated social touch on affective communication and social presence during a semi-collaborative LEGO assembly task. Across all participants, the robot and wearable device significantly impacted how participants perceived expressions of gratitude, calming, attention-grabbing, and sadness, evaluated through self-reported valence and arousal. The robot and wearable device in our setting did not show a significant effect on social presence. The observations from this exploratory study can inform the design of multimodal telepresence systems and interactions using non-anthropomorphic robots and mediated touch.

Wearable haptic systems for dance are often designed around normative bodies and prescriptive mappings that treat touch as an instructional signal. We present a disability centered haptic system designed to support dance improvisation through open-ended vibrotactile interaction. The system comprises a modular, flower-shaped wearable and a real-time graphical interface, without assuming fixed placement or inter pretation. This enables dancers and choreographers to author, record, and remix affective vibrotactile sequences during practice and performance, supporting improvisation and remote participation. Design decisions were grounded in a four-session co creative process with disabled dancers, emphasizing embodied and community-centered research practices. We evaluated our system through a usability study, an artistic qualitative evaluation with two disabled dancers, and a public participatory performance, demonstrating how shared vibrotactile sensation can support Disability-centering approaches to dance creation, relational sensing, and affective co-presence.

Individual differences in vibrotactile perception underscore the growing importance of personalization as haptic feedback becomes more prevalent in interactive systems. We propose Vibrotactile Preference Learning (VPL), a system that captures user-specific preference spaces over vibrotactile parameters via Gaussian-process-based uncertainty-aware preference learning. VPL uses an expected information gain-based acquisition strategy to guide query selection over 40 rounds of pairwise comparisons of overall user preference, augmented with user-reported uncertainty, enabling efficient exploration of the parameter space. We evaluate VPL in a user study (N = 13) using the vibrotactile feedback from a Microsoft Xbox controller, showing that it efficiently learns individualized preferences while maintaining comfortable, low-workload user interactions. These results highlight the potential of VPL for scalable personalization of vibrotactile experiences.

This article presents an evaluation of CrazyJoystick, a propeller-based handheld force-feedback device, for spatial navigation tasks in real-world and virtual reality environments. Building upon prior work validating the device's on-demand aerial deployment and directional cue discriminability, we investigated whether propeller-based kinesthetic torque cues can support effective wayfinding during continuous locomotion. We developed navigation-specific algorithms that generate egocentric directional cues using hierarchical decision logic optimized for dynamic heading corrections. Two user studies (N=12) compared CrazyJoystick with vibrotactile baselines. Study 1 evaluated multi-waypoint navigation through four path configurations in a real-world environment with visual occlusion; CrazyJoystick reduced completion time by 54.6% and path deviation by 25.8% relative to vibrotactile guidance. Study 2 assessed target localization in a VR treasure hunt with minimal lighting; CrazyJoystick enabled 43.2% faster completion and 79% higher walking speeds. Both studies revealed consistent workload reductions. These findings demonstrate that propeller-based kinesthetic feedback supports efficient navigation during sustained locomotion, establishing propeller-based torque directional cues as a viable alternative to vibrotactile encoding for dynamic wayfinding tasks.

Authoring realistic haptic textures typically requires low-level parameter tuning and repeated trial-and-error, limiting speed, transparency, and creative reach. We present a language-driven authoring system that turns natural-language prompts into multimodal textures: two coordinated haptic channels - sliding vibrations via force/speed-conditioned autoregressive (AR) models and tapping transients - and a text-prompted visual preview from a diffusion model. A shared, language-aligned latent links modalities so a single prompt yields semantically consistent haptic and visual signals; designers can write goals (e.g., "gritty but cushioned surface," "smooth and hard metal surface") and immediately see and feel the result through a 3D haptic device. To verify that the learned latent encodes perceptually meaningful structure, we conduct an anchor-referenced, attribute-wise evaluation for roughness, slipperiness, and hardness. Participant ratings are projected to the interpretable line between two real-material references, revealing consistent trends - asperity effects in roughness, compliance in hardness, and surface-film influence in slipperiness. A human-subject study further indicates coherent cross-modal experience and low effort for prompt-based iteration. The results show that language can serve as a practical control modality for texture authoring: prompts reliably steer material semantics across haptic and visual channels, enabling a prompt-first, designer-oriented workflow that replaces manual parameter tuning with interpretable, text-guided refinement.

We introduce an open-source toolkit for rapidly prototyping haptic harnesses via an integrated hardware-software workflow. The toolkit merges modular, 3-D printed components, magnetic connectors, and EVA-foam backings with an intuitive parametric software interface that automatically generates fabrication and assembly files. This design removes traditional CAD barriers, allowing researchers and designers to focus on haptic experience rather than mechanical design constraints. We evaluated the system through three complementary studies validating the hardware and software pipelines. First, a hardware evaluation conducted during an inclusive design workshop (n=18) demonstrated usability scores confirming accessibility across participants with diverse design experience. Second, a software usability study with haptics researchers (n=12) identified key interface refinements that guided version 2 improvements. Finally, an end-to-end workflow validation with experienced haptic researchers (n=8) assessed the complete design-to-deployment process. Researchers made custom harnesses in about 26 minutes, with 87.5 % reporting accurate actuator placement and faster iteration than traditional CAD-based methods. Across studies, the integrated system achieved a SUS score exceeding industry usability benchmarks. By combining accessible fabrication, streamlined software, and open-source dissemination, this toolkit lowers the entry barrier for haptic hardware development. It enables rapid, repeatable, and customizable design of wearable haptic interfaces, empowering broader participation in embodied interaction research.

This work presents a novel approach to fabricating soft capacitive tactile sensors using a surface crochet technique to embed conductive thread within crocheted textile substrates. The sensors are mechanically compliant, low-cost, removable, and can be incorporated into a wide range of semi-open-mesh textile substrates, including crocheted, knitted, and loosely woven fabrics. To examine the influence of textile structure and fiber material on sensing performance, we fabricated sensors from acrylic, bamboo, and faux fur yarns, and evaluated their binary touch detection accuracy across four force levels and their signal-to-noise ratio over 30 trials per material. A user study with 15 participants revealed that integrating the sensors significantly affected the perceived tactile qualities of each textile substrate. Finally, we evaluated the sensors in a potential real-world use case: enabling touch-based interactions with a soft, zoomorphic socially assistive robot. Quantitative and qualitative findings highlight trade-offs between sensor performance, perceived tactile qualities, and affective impressions of the robot, informing design considerations for integrating textile-based tactile sensing in soft robotic systems.

Reproducing realistic fluid interactions in Virtual Reality (VR) remains an open challenge due to their dynamic and multimodal nature. In this paper, we introduce SWIMVR, a wearable vibro-thermal haptic glove that simulates handwater interactions in VR through coordinated cold thermal and vibrotactile feedback. SWIMVR delivers event-driven, spatiotemporally modulated actuation to render both surface impact and submerged flow sensations. Built around 14 micro-thermoelectric cooling modules and 13 vibrotactile actuators per hand, the system operates in real-time with a VR ocean environment rendered in Unity. We conducted two user studies optimizing thermal waveform patterns for perceptual stability and comfort, and actuator layouts for perceptual fidelity with minimal hardware. Results show that triangular thermal modulation, achieved by cycling between two cooling levels rather than maintaining a fixed output, yields the most perceptually stable cold sensations, while a reduced actuator configuration closely matches the full hand in spatial coverage and subjective realism. A follow-up study con-firmed that palmar-only actuation can evoke cold sensations on the dorsal side, allowing further hardware reductions. SWIMVR demonstrates that timing and spatial targeting of multimodal cues can produce strong subjective impressions of water interaction in VR, offering a pathway towards scalable, untethered haptic feedback for immersive environments.

AI has transformed methods and knowledge across many domains. However, the intersection of AI and haptics remains underexplored. While modern AI techniques – fueled by machine learning and using powerful techniques such as generative modeling and reinforcement learning – offer powerful opportunities for advancing haptic design, insights from haptics research, such as perception modeling and adaptive interaction - grounded in human touch, embodiment, and multisensory integration — can also play a critical role in shaping more human-centered AI systems. This workshop will bring together an interdisciplinary community of researchers from HCI, haptics, AI, robotics, and design to (1) identify pressing questions in haptics that could benefit from AI approaches and (2) highlight ways in which haptic knowledge can support the development of embodied and context-aware AI. Through position papers and paper presentations, we will map key challenges, exchange methods, and explore new research directions that connect the two fields. By framing haptics and AI as mutually reinforcing, the workshop aims to build a shared research agenda and foster collaborations that advance both the science of touch and the design of intelligent interactive systems.

In May 2021, MPEG issued a call for proposals for the specification of a new coding format for haptic data. Following this call, a baseline reference design and associated software implementation were defined for the representation and coding of haptic data. It resulted in a standard that defines a complete generic framework for the delivery of haptic signals, allowing the development of current and future haptic applications in the mobile, gaming, and virtual reality domains. This paper introduces the results of the first phase of the MPEG haptics coding standard. It includes the description of the codec architecture, the current performances in terms of compression efficiency, and the plans for the coding representation and distribution of haptics. The publication of the final ISO international standard is expected in 2024

Physical touch, a fundamental aspect of human social interaction, remains largely absent in real-time virtual communication. We present a haptic-enabled multi-user Virtual Reality (VR) system that facilitates real-time, bi-directional social touch communication among physically distant users. We developed wearable gloves and forearm sleeves, embedded with 26 vibrotactile actuators for each hand and arm, actuated via a WiFi-based communication system. The system enables VR-transmitted data to be universally interpreted by haptic devices, allowing feedback rendering based on their capabilities. Users can perform and receive social touch gestures such as stroke, pat, poke, and squeeze, with other users within a shared virtual space or interact with other virtual objects, and they receive vibrotactile feedback. Through a two-part user study involving six pairs of participants, we investigate the impact of gesture speed, haptic feedback modality, and user roles, during real-time haptic communication in VR, on affective and sensory experiences, as well as evaluate the overall system usability. Our findings highlight key design considerations that significantly improve affective experiences, presence, embodiment, pleasantness, and naturalness, to foster more immersive and expressive mediated social touch experiences in VR.

We present CrazyJoystick, a flyable handheld joy-stick allowing seamless interaction methods to change between joystick and hand-tracking while displaying on-demand haptic feedback in extended reality (XR). Our system comprises a quadrotor that can autonomously approach the user when needed, addressing the limitations of conventional handheld and wearable devices that require continuous carrying throughout interactions. CrazyJoystick dynamically reallocates all thrust for haptic rendering during stationary states, eliminating the need to hover while delivering feedback. A customized cage allows users to grasp the device and interact with virtual objects, receiving 3.5 degree-of-freedom feedback. This novel transition method allows us to harvest the aerial mobility from multi-rotor based haptic devices, while having high force-to-weight ratios from being handheld during interaction. This paper describes the design and implementation of CrazyJoystick, evaluates its force and torque performance, and usability of the system in three VR applications. Our evaluation of torque rendering found that users can perceive the direction with an accuracy of 92.2%. User studies further indicated that the system significantly improves presence in VR environments. Participants found on-demand haptic feedback intuitive and enjoyable, emphasizing the potential of CrazyJoystick to redefine immersive interactions in XR through portable and adaptive feedback mechanisms.

Social touch is a common method of communication between individuals, but touch cues alone provide only a glimpse of the entire interaction. Visual and auditory cues are also present in these interactions, and increase the expressiveness and recognition of the conveyed information. However, most mediated touch interactions have focused on providing only haptic cues to the user. Our research addresses this gap by adding visual cues to a mediated social touch interaction through an array of LEDs attached to a wearable device. This device consists of an array of voice-coil actuators that present normal force to the user's forearm to recreate the sensation of social touch gestures. We conducted a human subject study (N = 20) to determine the relative importance of the touch and visual cues. Our results demonstrate that visual cues, particularly color and pattern, significantly enhance perceived realism, as well as alter perceived touch intensity, valence, and dominance of the mediated social touch. These results illustrate the importance of closely integrating multisensory cues to create more expressive and realistic virtual interactions.

In this paper, we present a method and a device designed to enhance the spatial efficiency of redirected walking (RDW) within virtual reality (VR). RDW is a VR technique that allows users to navigate larger virtual environments than the physical space permits by subtly altering their visual perception. The central challenge addressed is the alignment of haptic and visual perceptions of virtual objects, ensuring that both provide a unified experience, even if they deviate from the actual environment. By employing active kinesthetic feedback, our device seeks to bring the haptic perception of a virtual wall in harmony with its altered visual representation. We also introduce a novel algorithm that precisely gauges the position between a user’s hand and the virtual wall, providing consistent kinesthetic feedback. This research underscores the potential advantages and challenges of synchronizing manipulated visual and kinesthetic perceptions in VR contexts.

Group formation is fundamental for 3D displays that use Flying Light Specks, FLSs, to illuminate shapes and provide haptic interactions. An FLS is a drone with light sources that illuminates a shape. Groups of G FLSs may implement reliability techniques to tolerate FLS failures, provide kinesthetic haptic feedback in response to a user’s touch, and facilitate a divide and conquer approach to challenges such as localizing FLSs to render a shape. This paper evaluates four decentralized techniques to form groups. An FLS implements a technique autonomously using asynchronous communication and without a global clock. We evaluate these techniques using synthetic point clouds with known optimal solutions and real point clouds. Obtained results show a technique named Random Subset (RS) is superior when constructing small groups (G ≤ 5) while a different technique named Closest Available Neighbor First (CANF) is superior when constructing large groups (G ≥ 10).

We present a novel approach for simulating hardness and stiffness using an Encountered-Type Haptic Display (ETHD) with a dynamic end-effector. Addressing limitations in existing haptic rendering methods, our system allows dynamic adjustment of displayed hardness and stiffness. We conducted two experiments to assess users' perception of virtual blocks' hardness and stiffness using our device. Results indicate that physical hardness is a more salient feature than rendered stiffness. Evidence of stiffness masking was observed, particularly in high-hardness objects. Regardless of touch method (bare finger or stylus), participants were able to discern hardness and stiffness differences, with users finding it easier to distinguish hardness when tapping using a stylus.

Current Virtual Reality (VR) environments lack the haptic signals that humans experience during real-life interactions, such as the sensation of texture during lateral movement on a surface. Adding realistic haptic textures to VR environments requires a model that generalizes to variations of a user's interaction and to the wide variety of existing textures in the world. Current methodologies for haptic texture rendering exist, but they usually develop one model per texture, resulting in low scalability. We present a deep learning-based action-conditional model for haptic texture rendering and evaluate its perceptual performance in rendering realistic texture vibrations through a multi-part human user study. This model is unified over all materials and uses data from a vision-based tactile sensor (GelSight) to render the appropriate surface conditioned on the user's action in real-time. For rendering texture, we use a high-bandwidth vibrotactile transducer attached to a 3D Systems Touch device. The results of our user study shows that our learning-based method creates high-frequency texture renderings with comparable or better quality than state-of-the-art methods without the need to learn a separate model per texture. Furthermore, we show that the method is capable of rendering previously unseen textures using a single GelSight image of their surface.

The choice of haptic rendering tools plays a pivotal role in the perception of the simulated kinesthetic feedback. This paper introduces a novel approach using Crazyflie-based quadcopters as haptic rendering devices to simulate virtual stiffness. By designing a specialized cage and implementing control using Crazyswarm and both centralized and decentralized localization techniques, we implemented the smallest drone-based direct-touch encounter-type haptic feedback device. We evaluated three different proportional control levels, with each level simulating a different stiffness based on a distance-to-thrust response. We conducted a user study, which revealed that even with only 21 grams of the force output range, participants could distinguish between the proportional levels, perceiving higher proportional levels as increased stiffness. We also identified distinct vibration characteristics between cages made of different 3D printing materials. Our findings suggest that quadcopters can be effectively used as haptic tools, offering a controllable kinesthetic feedback system.