We introduce MoiréWidgets, a novel approach for tangible interaction that harnesses the Moiré effect—a prevalent optical phenomenon—to enable high-precision event detection on physical widgets. Unlike other electronics-free tangible user interfaces which require close coupling with external hardware, MoiréWidgets can be used at greater distances while maintaining high-resolution sensing of interactions. We define a set of interaction primitives, e.g., buttons, sliders, and dials, which can be used as standalone objects or combined to build complex physical controls. These consist of 3D printed structural mechanisms with patterns printed on two layers—one on paper and the other on a plastic transparency sheet—which create a visual signal that amplifies subtle movements, enabling the detection of user inputs. Our technical evaluation shows that our method outperforms standard fiducial markers and maintains sub-millimeter accuracy at 100 cm distance and wide viewing angles. We demonstrate our approach by creating an audio console and indicate how our approach could extend to other domains.
doi.org/10.1145/3613904.3642734
Hybrid board games (HBGs) augment their analog origins digitally (e.g., through apps) and are an increasingly popular pastime activity. Continuous world and character development and customization, known to facilitate engagement in video games, remain rare in HBGs. If present, they happen digitally or imaginarily, often leaving physical aspects generic. We developed DungeonMaker, a fabrication-augmented HBG bridging physical and digital game elements: 1) the setup narrates a story and projects a digital game board onto a laser cutter; 2) DungeonMaker assesses player-crafted artifacts; 3) DungeonMaker's modified laser head senses and moves player- and non-player figures, and 4) can physically damage figures. An evaluation (n=4x3) indicated that DungeonMaker provides an engaging experience, may support players' connection to their figures, and potentially spark novices' interest in fabrication. DungeonMaker provides a rich constellation to play HBGs by blending aspects of craft and automation to couple the physical and digital elements of an HBG tightly.
doi.org/10.1145/3613904.3642243
Surfaces with deformable and shape-changing properties seek to enhance and diversify tangible interactions with computing systems. However, we currently lack fundamental knowledge and user interface design principles that connect the inherent properties of deformable shapes with our human senses and cognitive associations. To address this knowledge gap, we systematically explored deformable shapes' cross-modal correspondences (CC) with colours and emotions. In our CC study, 52 participants were presented with deformable shape stimuli that varied in stiffness and angularity. They were asked to associate these stimuli with colours and emotions under (i) visuo-tactile and; (ii) tactile-only conditions. For the first time, our findings reveal (1) how stiffness level primarily influences the CC associations and; (2) that stiffness and angularity play a significant role in CC associations over the visibility of the shapes. The results were distilled into design guidelines for future deformable, shape-changing interfaces that engage specific human senses and responses.
doi.org/10.1145/3613904.3641952
Paper and touchscreen devices are two common objects found around us, and we investigated the potential of their intersection for tangible interface design. In this research, we developed PaperTouch, an approach to design paper based mechanisms that translate a variety of physical interactions to touch events on a capacitive touchscreen. These mechanisms act as switches that close during interaction, connecting the touchscreen to the device’s ground bus. To develop PaperTouch, we explored different types of paper along with the making process around them. We also built a range of applications to showcase different tangible interfaces facilitated with PaperTouch, including music instruments, educational dioramas, and playful products. By reflecting on this exploration, we uncovered the emerging design dimensions that considers the interactions, materiality, and embodiment of PaperTouch interfaces. We also surfaced the tacit know-how that we gained through our design process through annotations for others to refer to.
doi.org/10.1145/3613904.3642571
We present a new approach to address the challenges associated with maintaining the functionality of triboelectric vibration sensors in smart plywood during woodworking operations involving nails and screws. The current state-of-the-art sensor design employs non-overlapping electrodes, which unfortunately leads to significant compromises in terms of signal strength and clarity, particularly in real-world scenarios that involve electromagnetic (EM) interference. To overcome these limitations, we propose a method that enables the woodworker to manually isolate short-circuited electrodes. This method facilitates the creation of sensors using overlapping electrodes, while also incorporating EM shielding, thereby resulting in a substantial improvement in the sensor's robustness when detecting user activities. To validate the effectiveness of our proposed approach, we conducted a series of experiments, which not only shed light on the drawbacks of non-overlapping electrode designs but also demonstrated the significant improvements achieved through our method.
doi.org/10.1145/3613904.3642304