Smart yarns hold the potential to transform everyday textiles into functional platforms, yet current methods remain constrained. These include conductive yarns, made from silver or stainless steel, which retain the feel of conventional yarns but offer limited functions, and PCB-based solutions, which add capability at the cost of bulk and rigidity. We present Circuit2Yarn, a fabrication framework that transforms planar printed circuits into flexible yarns by rolling copper-traced TPU films with soldered surface-mount components, preserving the capabilities of rigid electronics while producing yarn-like forms suitable for textile integration. We demonstrate yarns as small as 0.8 mm that integrate LEDs and sensors, including temperature, humidity, light, IMU, and capacitive sensing modules, enabling applications ranging from smart garments and interactive musical instruments to responsive tea bags. Characterization confirms durability under bending/stretching. By rolling planar circuits into yarns, Circuit2Yarn paves the way toward comfortable, multifunctional, and interactive textiles in everyday life.

Material waste is an ongoing global challenge, with conventional recycling often proving neither economically viable nor environmentally sustainable. This pictorial explores an alternative approach by upcycling discarded plastic bags into reusable and functional materials for creative making practices. We present a set of fabrication techniques for working with fused plastic sheets and integrating them with DIY electronics, designed with disassembly in mind to support continued reuse and recyclability. Our contributions include: (1) Fabrication techniques for embedding removable electronics into upcycled plastic while preserving material integrity; (2) Design applications—three interactive prototypes that demonstrate the potential of upcycled plastic in sustainable smart design prototyping; and (3) Design insights—reflections on end-of-life considerations and the value of intentional, process-driven creation. This work contributes to the discourse on sustainable making and unmaking by positioning disassembly and reuse as central components in interaction design.

Electrophoretic Display (EPD) is a reflective technology that closely mimics traditional paper, making it a popular choice in E-readers, IoT devices, and wearables. However, color quantization, which is a critical step to display natural images on EPD with reduced color scales, usually leads to grayscale distortion and edge loss. In this paper, we propose a Dynamic-Clustering-based E-paper Color Quantization (DCECQ) method to address the above issue. First, it employs a dynamically adjustable Particle Swarm Optimization (PSO) clustering, facilitating adaptive threshold optimization for diverse image content. Second, it introduces a Human Visual System (HVS) based model to quantify visual errors and compensates for grayscale ghosting, effectively reducing artifacts such as edge blurring and color distortion. Third, it implements a validation platform for EPD to assess performance under real-world conditions. Experimental results demonstrate that our approach outperforms existing methods across multiple metrics, which attests to its effectiveness and practical applicability. Source code will be made publicly available after the peer review process.

Today’s electronics are manufactured to provide stable functionality and fixed physical forms optimized for reliable operation over long periods and repeated use. However, even when applications don’t call for such robustness, the permanency of these electronics comes with environmental consequences. In this paper, we describe an alternative approach that utilizes sustainable transient electronics whose method of destruction is also key to their functionality. We create these electronics through three different methods: 1) by inkjet printing conductive silver traces on poly(vinyl alcohol) (PVA) substrates to create water-soluble sensors; 2) by mixing a conductive beeswax material configured as a meltable sensor; and 3) by fabricating edible electronics with 3D printed chocolate and culinary gold leaf. To enable practical applications of these devices, we implement a fully transient and sustainable chipless RF detection system.

In this paper, we propose SwellSense, a fabrication technique to screen print stretchable circuits onto a special micro-capsule paper, creating localized swelling patterns with sensing capabilities. This simple technique will allow users to create a wide range of paper-based tactile interactive devices, which are mostly maintaining 2D planar form factor but can also be curved or folded into 3D interactive artifacts. We frst present the design guidelines to support various tactile interaction design including basic tactile graphic geometries, patterns with directional density, or fner interactive textures with embedded sensing such as touch sensor, pressure sensor, and mechanical switch. We then provide a design editor to enable users to design more creatively using the SwellSense technique. We provide a technical evaluation and user evaluation to validate the basic performance of SwellSense. Lastly, we demonstrate several application examples and conclude with a discussion on current limitations and future work.

While aging adults frequently prefer to "age in place", their children can worry about their well-being, especially when they live at a distance. Many in-home systems are designed to monitor the real-time status of seniors at home and provide information to their adult children. However, we observed that the needs and concerns of both sides in the information sharing process are often not aligned. In this research, we examined the design of a system that mitigates the privacy needs of aging adults in light of the information desires of adult children. We apply an iterative process to design and evaluate a visualization of indoor location data and compare its benefits to displaying raw video from cameras. We elaborate on the tradeoffs surrounding privacy and awareness made by older adults and their children, and synthesize design criteria for designing a visualization system to manage these tensions and tradeoffs.

This work presents PITAS, a thin-sheet robotic material composed of a reversible phase transition actuating layer and a heating/sensing layer. The synthetic sheet material enables non-expert makers to create shape-changing devices that can locally or remotely convey physical information such as shape, color, texture and temperature changes. PITAS sheets can be manipulated into various 2D shapes or 3D geometries using subtractive fabrication methods such as laser, vinyl, or manual cutting or an optional additive 3D printing method for creating 3D objects. After describing the design of PITAS, this paper also describes a study conducted with thirteen makers to gauge the accessibility, design space, and limitations encountered when PITAS is used as a soft robotic material while designing physical information communication devices. Lastly, this work reports on the results of a mechanical and electrical evaluation of PITAS and presents application examples to demonstrate its utility.

This paper presents FlexHaptics, a design method for creating custom haptic input interfaces. Our approach leverages planar compliant structures whose force-deformation relationship can be altered by adjusting the geometries. Embedded with such structures, a FlexHaptics module exerts a fine-tunable haptic effect (i.e., resistance, detent, or bounce) along a movement path (i.e., linear, rotary, or ortho-planar). These modules can work separately or combine into an interface with complex movement paths and haptic effects. To enable the parametric design of FlexHaptic modules, we provide a design editor that converts user-specified haptic properties into underlying mechanical structures of haptic modules. We validate our approach and demonstrate the potential of FlexHaptic modules through six application examples, including a slider control for a painting application and a piano keyboard interface on touchscreens, a tactile low vision timer, VR game controllers, and a compound input device of a joystick and a two-step button.

Airflow energy harvesting has attracted much attention in the community of energy harvesting, but the efforts to make it accessible for individual users have been limited. In this paper, we address this issue and demonstrate a comprehensive toolkit, Exergy, which can help and support novice users to simulate, design, and manufacture an airflow energy harvester for vehicles.

We present Self-powered Paper INterfaces (SPIN) combining folding paper creases with triboelectric nanogenerator (TENG). Embedding TENG into paper creases, we developed a design editor and set of fabrication techniques to create paper-based interfaces that power sensors and actuators. Our SPIN design editor enables users to design their own crease pattern by changing parameters, embed power generating modules into the design, estimate total power generation, and export the files. Then following the fabrication instructions, users can cut and crease materials, and assemble them to build their own interfaces. We employ repetitive push-and-pull based embodied interactions with the mechanism of paper creases and demonstrate four application examples that show new expressive possibilities applying different scales of embodied interactions.

We develop a novel method printing complex self-folding geometries. We demonstrated that with a desktop fused deposition modeling (FDM) 3D printer, off-the-shelf printing filaments and a design editor, we can print flat thermoplastic composites and trigger them to self-fold into 3D with arbitrary bending angles. This is a suitable technique, called Thermorph, to prototype hollow and foldable 3D shapes without losing key features. We describe a new curved folding origami design algorithm, compiling given arbitrary 3D models to 2D unfolded models in G-Code for FDM printers. To demonstrate the Thermorph platform, we designed and printed complex self-folding geometries (up to 70 faces), including 15 self-curved geometric primitives and 4 self-curved applications, such as chairs, the simplified Stanford Bunny and flowers. Compared to the standard 3D printing, our method saves up to 60% - 87% of the printing time for all shapes chosen.

We present a printed paper actuator as a low cost, reversible and electrical actuation and sensing method. This is a novel but easily accessible enabling technology that expands upon the library of actuation-sensing materials in HCI. By integrating three physical phenomena, including the bilayer bending actuation, the shape memory effect of the thermoplastic and the current-driven joule heating via conductive printing filament, we developed the actuator by simply printing a single layer conductive Polylactide (PLA) on a piece of copy paper via a desktop fused deposition modeling (FDM) 3D printer. This paper describes the fabrication process, the material mechanism, and the transformation primitives, followed by the electronic sensing and control methods. A software tool that assists the design, simulation and printing toolpath generation is introduced. Finally, we explored applications under four contexts: robotics, interactive art, entertainment and home environment.