Reconfigurable physical interfaces empower users to swiftly adapt to tailored design requirements or preferences. Shape-changing interfaces enable such reconfigurability, avoiding the cost of refabrication or part replacements. Nonetheless, reconfigurable interfaces are often bulky, expensive, or inaccessible. We propose a reversible shape-changing mechanism that enables reconfigurable 3D printed structures via translations and rotations of parts. We investigate fabrication techniques that enable reconfiguration using magnets and the thermoplasticity of heated polymer. Proposed interfaces achieve tunable haptic feedback and adjustment of different user affordances by reconfiguring input motions. The design space is demonstrated through applications in rehabilitation, embodied communication, accessibility, safety, and gaming.

3D printed displays promise to create unique visual interfaces for physical objects. However, current methods for creating 3D printed displays either require specialized post-fabrication processes (e.g., electroluminescence spray and silicon casting) or function as passive elements that simply react to environmental factors (e.g., body and air temperature). These passive displays offer limited control over when, where, and how the colors change. In this paper, we introduce ThermoPixels, a method for designing and 3D printing actively controlled and visually rich thermochromic displays that can be embedded in arbitrary geometries. We investigate the color-changing and thermal properties of thermochromic and conductive filaments. Based on these insights, we designed ThermoPixels and an accompanying software tool that allows embedding ThermoPixels in arbitrary 3D geometries, creating displays of various shapes and sizes (flat, curved, or matrix displays) or displays that embed textures, multiple colors, or that are flexible.

The advent of user-friendly embedded prototyping systems, exemplified by platforms like Arduino, has significantly democratized the creation of interactive devices that combine software programs with electronic hardware. This interconnection between hardware and software, however, makes the identification of bugs very difficult, as problems could be rooted in the program, in the circuit, or at their intersection. While there are tools to assist in identifying and resolving bugs, they typically require hardware instrumentation or visualizing logs in serial monitors. Based on the findings of a formative study, we designed Inline a programming tool that simplifies debugging of embedded systems by making explicit the internal state of the hardware and the program's execution flow using visualizations of the hardware logs directly within the user's code. The system's key characteristics are 1) an inline presentation of logs within the code, 2) real-time tracking of the execution flow, and 3) an expression language to manipulate and filter the logs. The paper presents the detailed implementation of the system and a study with twelve users, which demonstrates what features were adopted and how they were leveraged to complete debugging tasks.

The unique behaviors of thermoplastic polymers enable shape-changing interfaces made of 3D printed objects that do not require complex electronics integration. While existing techniques rely on external trigger, such as heat, applied globally on a 3D printed object initiating all at once the shape-changing response (e.g., hot water, heat gun, oven), independent control of multiple parts of the object becomes nearly impossible. We introduce ShrinkCells, a set of shape-changing actuators that enables localized heat to shrink or bend, through combining the properties of two materials — conductive PLA is used to generate localized heat which selectively triggers the shrinking of a Shape Memory Polymer. The unique benefit of ShrinkCells is their capability of triggering simultaneous or sequential shape transformations for different geometries using a single power supply. This results in 3D printed rigid structures that actuate in sequence, avoiding self-collisions when unfolding. We contribute to the body of literature on 4D fabrication by a systematic investigation of selective heating with two different materials, the design and evaluation of the ShrinkCells shape-changing primitives, and applications demonstrating the usage of these actuators.

Current head-mounted displays enable users to explore virtual worlds by simply walking through them (i.e., real-walking VR). This led researchers to create haptic displays that can also simulate different types of elevation shapes. However, existing shape-changing floors are limited by their tabletop scale or the coarse resolution of the terrains they can display due to the limited number of actuators and low vertical resolution. To tackle this challenge, we introduce Elevate, a dynamic and walkable pin-array floor on which users can experience not only large variations in shapes but also the details of the underlying terrain. Our system achieves this by packing 1200 pins arranged on a 1.80 × 0.60m platform, in which each pin can be actuated to one of ten height levels (resolution: 15mm/level). To demonstrate its applicability, we present our haptic floor combined with four walkable applications and a user study that reported increased realism and enjoyment.