Verisimilitude as Boon and Bane: How People Initiate Opportunistic Interactions at Professional Events in Social VROpportunistic interactions, the unstructured exchanges that emerge as individuals become aware of each other's presence, are essential for relationship building and information sharing in everyday life. Yet, fostering effective opportunistic interactions has proven challenging, especially at professional events that have increasingly transitioned from in-person to online formats. In the current paper, we offer an in-depth qualitative account of how people initiate opportunistic interactions in social VR. Our participants consisted of 16 individuals with ongoing experience attending VR-mediated events in their professional communities. We conducted extensive observations with each participant during one or more events they attended. We also interviewed them after every observed event, obtaining self-reflections on their attempts to navigate opportunistic interactions with others. Our analysis revealed that participants sought to understand the extent to which social VR preserved the real-world meanings of various nonverbal cues, which we refer to as verisimilitude. We detailed the unique connections between a person's perceived verisimilitude and their social behaviors at each of the three steps toward initiating opportunistic interactions: availability recognition, attention capture, and ice-breaking. Across these steps, the VR platform typically replaces complex social mechanisms with feasible technical ones in order to function, thereby altering the preconditions necessary for a nonverbal cue’s social meanings to remain intact. We identified a rich set of strategies that participants developed to assess verisimilitude and act upon it, while also confirming a lack of systematic knowledge guiding their practices. Based on these findings, we provide actionable insights for social VR platform design that can best support the initiation of opportunistic interactions for professional purposes.2025VCVictoria Chang et al.Collaborating in Virtual EnvironmentsCSCW
DissolvPCB: Fully Recyclable 3D-Printed Electronics with Liquid Metal Conductors and PVA SubstratesWe introduce DissolvPCB, an electronic prototyping technique for fabricating fully recyclable printed circuit board assemblies (PCBAs) using affordable FDM 3D printing, with polyvinyl alcohol (PVA) as a water-soluble substrate and eutectic gallium-indium (EGaIn) as the conductive material. When obsolete, the PCBA can be easily recycled by immersing it in water: the PVA dissolves, the EGaIn re-forms into a liquid metal bead, and the electronic components are recovered. These materials can then be reused to fabricate a new PCBA. We present the DissolvPCB workflow, characterize its design parameters, evaluate the performance of circuit produced with it, and quantify its environmental impact through a lifecycle assessment (LCA) comparing it to conventional CNC-milled FR-4 boards. We further develop a software plugin that automatically converts PCB design files into 3D-printable circuit substrate models. To demonstrate the capabilities of DissolvPCB, we fabricate and recycle three functional prototypes: a Bluetooth speaker featuring a double-sided PCB, a finger fidget toy with a 3D circuit topology, and a shape-changing gripper enabled by joule heat driven 4D printing. The paper concludes with a discussion of current technical limitations and opportunities for future directions.2025ZYZeyu Yan et al.Desktop 3D Printing & Personal FabricationShape-Changing Materials & 4D PrintingEcological Design & Green ComputingUIST
Cybernetic Marionette: Channeling Collective Agency Through a Wearable Robot in a Live Dancer-Robot DuetWe describe Dance^2, an interactive dance performance in which audience members channel their collective agency into a dancer-robot duet by voting on the behavior of a wearable robot affixed to the dancer’s body. At key moments during the performance, the audience is invited to either continue the choreography or override it, shaping the unfolding interaction through real-time collective input. While post-performance surveys revealed that participants felt their choices meaningfully influenced the performance, voting data across four public performances exhibited strikingly consistent patterns. This tension between what audience members do, what they feel, and what actually changes highlights a complex interplay between agentive behavior, the experience of agency, and power. We reflect on how choreography, interaction design, and the structure of the performance mediate this relationship, offering a live analogy for algorithmically curated digital systems where agency is felt, but not exercised.2025ASAnup Sathya et al.Shape-Changing Interfaces & Soft Robotic MaterialsFull-Body Interaction & Embodied InputDance & Body Movement ComputingDIS
Datamancer: Bimanual Gesture Interaction in Multi-Display Ubiquitous Analytics EnvironmentsWe introduce Datamancer, a wearable device enabling bimanual gesture interaction across multi-display ubiquitous analytics environments. Datamancer addresses the gap in gesture-based interaction within data visualization settings, where current methods are often constrained by limited interaction spaces or the need for installing bulky tracking setups. Datamancer integrates a finger-mounted pinhole camera and a chest-mounted gesture sensor, allowing seamless selection and manipulation of visualizations on distributed displays. By pointing to a display, users can acquire the display and engage in various interactions, such as panning, zooming, and selection, using both hands. Our contributions include (1) an investigation of the design space of gestural interaction for physical ubiquitous analytics environments; (2) a prototype implementation of the Datamancer system that realizes this model; and (3) an evaluation of the prototype through demonstration of application scenarios, an expert review, and a user study.2025BPBiswaksen Patnaik et al.University of Maryland College Park, Department of Computer ScienceFull-Body Interaction & Embodied InputInteractive Data VisualizationContext-Aware ComputingCHI
Rhapso: Automatically Embedding Fiber Materials into 3D Prints for Enhanced InteractivityWe introduce Rhapso, a 3D printing system designed to embed a diverse range of continuous fiber materials within 3D objects during the printing process. This approach enables integrating properties like tensile strength, force storage and transmission, or aesthetic and tactile characteristics, directly into low-cost thermoplastic 3D prints. These functional objects can have intricate actuation, self-assembly, and sensing capabilities with little to no manual intervention. To achieve this, we modify a low-cost Fused Filament Fabrication (FFF) 3D printer, adding a stepper motor-controlled fiber spool mechanism on a gear ring above the print bed. In addition to hardware, we provide parsing software for precise fiber placement, which generates Gcode for printer operation. To illustrate the versatility of our system, we present applications that showcase its extensive design potential. Additionally, we offer comprehensive documentation and open designs, empowering others to replicate our system and explore its possibilities.2024DADaniel Ashbrook et al.3D Modeling & AnimationDesktop 3D Printing & Personal FabricationShape-Changing Materials & 4D PrintingUIST
JetUnit: Rendering Diverse Force Feedback in Virtual Reality Using Water JetsWe propose JetUnit, a water-based VR haptic system designed to produce force feedback with a wide spectrum of intensities and frequencies through water jets. The key challenge in designing this system lies in optimizing parameters to enable the haptic device to generate force feedback that closely replicates the most intense force produced by direct water jets while ensuring the user remains dry. In this paper, we present the key design parameters of the JetUnit wearable device determined through a set of quantitative experiments and a perception study. We further conducted a user study to assess the impact of integrating our haptic solutions into virtual reality experiences. The results revealed that, by adhering to the design principles of JetUnit, the water-based haptic system is capable of delivering diverse force feedback sensations, significantly enhancing the immersive experience in virtual reality.2024ZZZining Zhang et al.Force Feedback & Pseudo-Haptic WeightFull-Body Interaction & Embodied InputUIST
VisTorch: Interacting with Situated Visualizations using Handheld ProjectorsSpatial data is best analyzed in situ, but existing mixed reality technologies can be bulky, expensive, or unsuitable for collaboration. We present VisTorch: a handheld device for projected situated analytics consisting of a pico-projector, a multi-spectrum camera, and a touch surface. VisTorch enables viewing charts situated in physical space by simply pointing the device at a surface to reveal visualizations in that location. We evaluated the approach using both a user study and an expert review. In the former, we asked 20 participants to first organize charts in space and then refer to these charts to answer questions. We observed three spatial and one temporal pattern in participant analyses. In the latter, four experts---a museum designer, a statistical software developer, a theater designer, and an environmental educator---utilized VisTorch to derive practical scenarios. Results from our study showcase the utility of situated visualizations for memory and recall.2024BPBiswaksen Patnaik et al.University of Maryland College ParkGeospatial & Map VisualizationData PhysicalizationCHI
SolderlessPCB: Reusing Electronic Components in PCB Prototyping through Detachable 3D Printed HousingsThe iterative prototyping process for printed circuit boards (PCBs) frequently employs surface-mounted device (SMD) components, which are often discarded rather than reused due to the challenges associated with desoldering, leading to unnecessary electronic waste. This paper introduces SolderlessPCB, a collection of techniques for solder-free PCB prototyping, specifically designed to promote the recycling and reuse of electronic components. Central to this approach are custom 3D-printable housings that allow SMD components to be mounted onto PCBs without soldering. We detail the design of SolderlessPCB and the experiments conducted to evaluate its design parameters, electrical performance, and durability. To illustrate the potential for reusing SMD components with SolderlessPCB, we discuss two scenarios: the reuse of components from earlier design iterations and from obsolete prototypes. We also provide examples demonstrating that SolderlessPCB can handle high-current applications and is suitable for high-speed data transmission. The paper concludes by discussing the limitations of our approach and suggesting future directions to overcome these challenges.2024ZYZeyu Yan et al.University Of MarylandDesktop 3D Printing & Personal FabricationCircuit Making & Hardware PrototypingCHI
3D Printing Magnetophoretic DisplaysWe present a pipeline for printing interactive and always-on magnetophoretic displays using affordable FDM 3D printers. Using our pipeline, an end-user can convert the surface of a 3D shape into a matrix of voxels. The generated model can be sent to an FDM 3D printer equipped with an additional syringe-based injector. During the printing process, an oil and iron powder-based liquid mixture is injected into each voxel cell, allowing the appearance of the once-printed object to be editable with external magnetic sources. To achieve this, we conducted modifications to the 3D printer hardware and the firmware. We also implemented a 3D editor to prepare printable models. We demonstrate our pipeline with a variety of examples, including a printed Stanford bunny with customizable appearances, a small espresso mug that can be used as a post-it note surface, a board game figurine with a computationally updated display, and a collection of flexible wearable accessories with editable visuals.2023ZYZeyu Yan et al.Shape-Changing Interfaces & Soft Robotic MaterialsDesktop 3D Printing & Personal FabricationLaser Cutting & Digital FabricationUIST
Toucha11y: Making Inaccessible Public Touchscreens AccessibleDespite their growing popularity, many public kiosks with touchscreens are inaccessible to blind people. Toucha11y is a working prototype that allows blind users to use existing inaccessible touchscreen kiosks independently and with little effort. Toucha11y consists of a mechanical bot that can be instrumented to an arbitrary touchscreen kiosk by a blind user and a companion app on their smartphone. The bot, once attached to a touchscreen, will recognize its content, retrieve the corresponding information from a database, and render it on the user's smartphone. As a result, a blind person can use the smartphone's built-in accessibility features to access content and make selections. The mechanical bot will detect and activate the corresponding touchscreen interface. We present the system design of Toucha11y along with a series of technical evaluations. Through a user study, we found out that Toucha11y could help blind users operate inaccessible touchscreen devices.2023JLJiasheng Li et al.University of MarylandVisual Impairment Technologies (Screen Readers, Tactile Graphics, Braille)Deaf & Hard-of-Hearing Support (Captions, Sign Language, Vibration)CHI
TangibleGrid: Tangible Web Layout Design for Blind UsersWe present TangibleGrid, a novel device that allows blind users to understand and design the layout of a web page with real-time tangible feedback. We conducted semi-structured interviews and a series of co-design sessions with blind users to elicit insights that guided the design of TangibleGrid. Our final prototype contains shape-changing brackets representing the web elements and a baseboard representing the web page canvas. Blind users can design a web page layout through creating and editing web elements by snapping or adjusting tangible brackets on top of the baseboard. The baseboard senses the brackets' type, size, and location, verbalizes the information, and renders the web page on the client browser. Through a formative user study, we found that blind users could understand a web page layout through TangibleGrid. They were also able to design a new web layout from scratch without the help of sighted people.2022JLDavid Li et al.Visual Impairment Technologies (Screen Readers, Tactile Graphics, Braille)Universal & Inclusive DesignUIST
Fibercuit: Prototyping High-Resolution Flexible and Kirigami Circuits with a Fiber Laser EngraverPrototyping compact devices with unique form factors often requires the PCB manufacturing process to be outsourced, which can be expensive and time-consuming. In this paper, we present Fibercuit, a set of rapid prototyping techniques to fabricate high-resolution, flexible circuits on-demand using a fiber laser engraver. We showcase techniques that can laser cut copper-based composites to form fine-pitch conductive traces, laser fold copper substrates that can form kirigami structures, and laser solder surface-mount electrical components using off-the-shelf soldering pastes. Combined with our software pipeline, an end user can design and fabricate flexible circuits which are dual-layer and three-dimensional, thereby exhibiting a wide range of form factors. We demonstrate Fibercuit by showcasing a set of examples, including a custom dice, flex cables, custom end-stop switches, electromagnetic coils, LED earrings and a circuit in the form of kirigami crane.2022ZYZeyu Yan et al.Shape-Changing Interfaces & Soft Robotic MaterialsLaser Cutting & Digital FabricationCircuit Making & Hardware PrototypingUIST
Kinergy: Creating 3D Printable Motion using Embedded Kinetic EnergyWe present Kinergy—an interactive design tool for creating self-propelled motion by harnessing the energy stored in 3D printable springs. To produce controllable output motions, we introduce 3D printable kinetic units, a set of parameterizable designs that encapsulate 3D printable springs, compliant locks, and transmission mechanisms for three non-periodic motions—instant translation, instant rotation, continuous translation—and four periodic motions—continuous rotation, reciprocation, oscillation, intermittent rotation. Kinergy allows the user to create motion-enabled 3D models by embedding kinetic units, customize output motion characteristics by parameterizing embedded springs and kinematic elements, control energy by operating the specialized lock, and preview the resulting motion in an interactive environment. We demonstrate the potential of our techniques via example applications from spring-loaded cars to kinetic sculptures and close with a discussion of key challenges such as geometric constraints.2022LHLiang He et al.Shape-Changing Interfaces & Soft Robotic MaterialsDesktop 3D Printing & Personal FabricationUIST
FabHydro: Printing Interactive Hydraulic Devices with an Affordable SLA 3D PrinterWe introduce FabHydro, a set of rapid and low-cost methods to prototype interactive hydraulic devices based on an off-the-shelf 3D printer and flexible photosensitive resin. We first present printer settings and custom support structures to warrant the successful print of flexible and deformable objects. We then demonstrate two printing methods to seal the transmission fluid inside these deformable structures: the Submerged Printing process that seals the liquid resin without manual assembly, and the Printing with Plugs method that allows the use of different transmission fluids without modification to the printer. Following the printing methods, we report a design space with a range of 3D printable primitives, including the hydraulic generator, transmitter, and actuator. To demonstrate the feasibility of our approaches and the breadth of new designs that they enable, we showcase a set of examples from a printed robotic gripper that can be operated at a distance to a mobile phone stand that serves as a status reminder by repositioning the user's phone. We conclude with a discussion of our approach's limitations and possible future improvements.2021ZYZeyu Yan et al.Desktop 3D Printing & Personal FabricationShape-Changing Materials & 4D PrintingUIST
MechanoBeat: Monitoring Interactions with Everyday Objects using 3D Printed Harmonic Oscillators and Ultra-Wideband RadarIn this paper we present MechanoBeat, a 3D printed mechanical tag that oscillates at a unique frequency upon user interaction. With the help of an ultra-wideband (UWB) radar array, MechanoBeat can unobtrusively monitor interactions with both stationary and mobile objects. MechanoBeat consists of small, scalable, and easy-to-install tags that do not require any batteries, silicon chips, or electronic components. Tags can be produced using commodity desktop 3D printers with cheap materials. We develop an effcient signal processing and deep learning method to locate and identify tags using only the signals refected from the tag vibrations. MechanoBeat is capable of detecting simultaneous interactions with high accuracy, even in noisy environments. We leverage UWB radar signals’ high penetration property to sense interactions behind walls in a non-line-of-sight (NLOS) scenario. A number of applications using MechanoBeat have been explored and the results have been presented in the paper.2020MOMd. Farhan Tasnim Oshim et al.Biosensors & Physiological MonitoringCircuit Making & Hardware PrototypingUIST
Ondulé: Designing and Controlling 3D Printable SpringsWe present Ondulé, a novel computational design tool to add elastic deformation behaviors to static 3D models using a combination of 3D-printed springs and mechanical joints. Springs are unique because they can exert expressive deformation behaviors and store mechanical energy. Informed by spring theory and our empirical mechanical experiments, we introduce spring and joint-based design techniques that support a range of parameterizable deformation behaviors, including compress, extend, twist, bend, and various combinations. To enable users to design and add these 3D-printable deformations to their models, we introduce a custom spring design tool for Rhino. Here, users can convert selected geometries into springs, customize spring stiffness, and parameterize their design to obtain a desired deformation behavior. To demonstrate the feasibility of our approach and the breadth of new 3D-printable designs that it enables, we showcase a set of example applications from launching rocket toys to tangible storytelling props. We conclude with a discussion of key challenges and open research questions.2019LHLiang He et al.Shape-Changing Interfaces & Soft Robotic MaterialsShape-Changing Materials & 4D PrintingUIST