Incorporating accurate physics-based simulation into interactive design tools is challenging. However, adding the physics accurately becomes crucial to several emerging technologies. For example, in virtual augmented reality (VR AR) videos, the faithful reproduction of surrounding audios is required to bring the immersion to the next level. Similarly, as personal fabrication is made possible with accessible 3D printers, more intuitive tools that respect the physical constraints can help artists to prototype designs. One main hurdle is the sheer amount of computation complexity to accurately reproduce the real-world phenomena through physics-based simulation. In my thesis research, I develop interactive tools that implement efficient physics-based simulation algorithms for automatic optimization and intuitive user interaction.
To ease the design process, various interactive tools have been proposed. For example, in order to add sensors into 3D printed objects, Capricate designs custom-shaped sensors that fit on complex surfaces and automatically wire the underlying sensors @cite_5 . Another design tool, aeroMorph, focuses on simulating bending mechanism that creates shape-changing behaviors with common materials, such as paper and plastics @cite_0 . With the interactive visualization, users receive feedbacks interactively as they work on the design. This tool provides great flexibility for them, bypassing time-consuming traditional validation approaches which require repeated fabrication. Platener, a low-fidelity fabrication tool, shows users an interactive interface with a global slider to define the fidelity-speed trade-off, making it easier to decide on fabrication fidelity @cite_1 . My goal is to develop interactive tools and augment them with efficient physics-based simulations and optimization, providing more accurate interactive feedback on complex problems.
@cite_0 @cite_5 @cite_1
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With significant data missing in a point scan, reconstructing a complete surface with sufficient geometric and topological fidelity is highly challenging. We present an interactive technique for surface reconstruction from incomplete and sparse scans of 3D objects possessing sharp features. A fundamental premise of our interaction paradigm is that directly editing data in 3D is not only counterintuitive but also ineffective, while working with 1D entities (i.e., curves) is a lot more manageable. To this end, we factor 3D editing into two "orthogonal" interactions acting on skelet al and profile curves of the underlying shape, controlling its topology and geometric features, respectively. For surface completion, we introduce a novel skeleton-driven morph-to-fit, or morfit, scheme which reconstructs the shape as an ensemble of generalized cylinders. Morfit is a hybrid operator which optimally interpolates between adjacent curve profiles (the "morph") and snaps the surface to input points (the "fit"). The interactive reconstruction iterates between user edits and morfit to converge to a desired final surface. We demonstrate various interactive reconstructions from point scans with sharp features and significant missing data. 3D printing is widely used to physically prototype the look and feel of 3D objects. Interaction possibilities of these prototypes, however, are often limited to mechanical parts or post-assembled electronics. In this paper, we present Capricate, a fabrication pipeline that enables users to easily design and 3D print highly customized objects that feature embedded capacitive multi-touch sensing. The object is printed in a single pass using a commodity multi-material 3D printer. To enable touch input on a wide variety of 3D printable surfaces, we contribute two techniques for designing and printing embedded sensors of custom shape. The fabrication pipeline is technically validated by a series of experiments and practically validated by a set of example applications. They demonstrate the wide applicability of Capricate for interactive objects. We present a novel method to obtain fine-scale detail in 3D reconstructions generated with low-budget RGB-D cameras or other commodity scanning devices. As the depth data of these sensors is noisy, truncated signed distance fields are typically used to regularize out the noise, which unfortunately leads to over-smoothed results. In our approach, we leverage RGB data to refine these reconstructions through shading cues, as color input is typically of much higher resolution than the depth data. As a result, we obtain reconstructions with high geometric detail, far beyond the depth resolution of the camera itself. Our core contribution is shading-based refinement directly on the implicit surface representation, which is generated from globally-aligned RGB-D images. We formulate the inverse shading problem on the volumetric distance field, and present a novel objective function which jointly optimizes for fine-scale surface geometry and spatially-varying surface reflectance. In order to enable the efficient reconstruction of sub-millimeter detail, we store and process our surface using a sparse voxel hashing scheme which we augment by introducing a grid hierarchy. A tailored GPU-based Gauss-Newton solver enables us to refine large shape models to previously unseen resolution within only a few seconds. This paper presents a design, simulation, and fabrication pipeline for making transforming inflatables with various materials. We introduce a bending mechanism that creates multiple, programmable shape-changing behaviors with inextensible materials, including paper, plastics and fabrics. We developed a software tool that generates these bending mechanism for a given geometry, simulates its transformation, and exports the compound geometry as digital fabrication files. We show a range of fabrication methods, from manual sealing, to heat pressing with custom stencils and a custom heat-sealing head that can be mounted on usual 3-axis CNC machines to precisely fabricate the designed transforming material. Finally, we present three applications to show how this technology could be used for designing interactive wearables, toys, and furniture.