TY - THES AB - Fabrication of curved shells plays an important role in modern design, industry, and science. Among their remarkable properties are, for example, aesthetics of organic shapes, ability to evenly distribute loads, or efficient flow separation. They find applications across vast length scales ranging from sky-scraper architecture to microscopic devices. But, at the same time, the design of curved shells and their manufacturing process pose a variety of challenges. In this thesis, they are addressed from several perspectives. In particular, this thesis presents approaches based on the transformation of initially flat sheets into the target curved surfaces. This involves problems of interactive design of shells with nontrivial mechanical constraints, inverse design of complex structural materials, and data-driven modeling of delicate and time-dependent physical properties. At the same time, two newly-developed self-morphing mechanisms targeting flat-to-curved transformation are presented. In architecture, doubly curved surfaces can be realized as cold bent glass panelizations. Originally flat glass panels are bent into frames and remain stressed. This is a cost-efficient fabrication approach compared to hot bending, when glass panels are shaped plastically. However such constructions are prone to breaking during bending, and it is highly nontrivial to navigate the design space, keeping the panels fabricable and aesthetically pleasing at the same time. We introduce an interactive design system for cold bent glass façades, while previously even offline optimization for such scenarios has not been sufficiently developed. Our method is based on a deep learning approach providing quick and high precision estimation of glass panel shape and stress while handling the shape multimodality. Fabrication of smaller objects of scales below 1 m, can also greatly benefit from shaping originally flat sheets. In this respect, we designed new self-morphing shell mechanisms transforming from an initial flat state to a doubly curved state with high precision and detail. Our so-called CurveUps demonstrate the encodement of the geometric information into the shell. Furthermore, we explored the frontiers of programmable materials and showed how temporal information can additionally be encoded into a flat shell. This allows prescribing deformation sequences for doubly curved surfaces and, thus, facilitates self-collision avoidance enabling complex shapes and functionalities otherwise impossible. Both of these methods include inverse design tools keeping the user in the design loop. AU - Guseinov, Ruslan ID - 8366 KW - computer-aided design KW - shape modeling KW - self-morphing KW - mechanical engineering SN - 2663-337X TI - Computational design of curved thin shells: From glass façades to programmable matter ER - TY - JOUR AB - Cold bent glass is a promising and cost-efficient method for realizing doubly curved glass facades. They are produced by attaching planar glass sheets to curved frames and require keeping the occurring stress within safe limits. However, it is very challenging to navigate the design space of cold bent glass panels due to the fragility of the material, which impedes the form-finding for practically feasible and aesthetically pleasing cold bent glass facades. We propose an interactive, data-driven approach for designing cold bent glass facades that can be seamlessly integrated into a typical architectural design pipeline. Our method allows non-expert users to interactively edit a parametric surface while providing real-time feedback on the deformed shape and maximum stress of cold bent glass panels. Designs are automatically refined to minimize several fairness criteria while maximal stresses are kept within glass limits. We achieve interactive frame rates by using a differentiable Mixture Density Network trained from more than a million simulations. Given a curved boundary, our regression model is capable of handling multistable configurations and accurately predicting the equilibrium shape of the panel and its corresponding maximal stress. We show predictions are highly accurate and validate our results with a physical realization of a cold bent glass surface. AU - Gavriil, Konstantinos AU - Guseinov, Ruslan AU - Perez Rodriguez, Jesus AU - Pellis, Davide AU - Henderson, Paul M AU - Rist, Florian AU - Pottmann, Helmut AU - Bickel, Bernd ID - 8562 IS - 6 JF - ACM Transactions on Graphics SN - 0730-0301 TI - Computational design of cold bent glass façades VL - 39 ER - TY - DATA AB - Supplementary movies showing the following sequences for spatio-temporarily programmed shells: input geometry and actuation time landscape; comparison of morphing processes from a camera recording and a simulation; final actuated shape. AU - Guseinov, Ruslan ID - 8375 TI - Supplementary data for "Computational design of curved thin shells: from glass façades to programmable matter" ER - TY - DATA AU - Guseinov, Ruslan ID - 8761 TI - Supplementary data for "Computational design of cold bent glass façades" ER - TY - JOUR AB - Advances in shape-morphing materials, such as hydrogels, shape-memory polymers and light-responsive polymers have enabled prescribing self-directed deformations of initially flat geometries. However, most proposed solutions evolve towards a target geometry without considering time-dependent actuation paths. To achieve more complex geometries and avoid self-collisions, it is critical to encode a spatial and temporal shape evolution within the initially flat shell. Recent realizations of time-dependent morphing are limited to the actuation of few, discrete hinges and cannot form doubly curved surfaces. Here, we demonstrate a method for encoding temporal shape evolution in architected shells that assume complex shapes and doubly curved geometries. The shells are non-periodic tessellations of pre-stressed contractile unit cells that soften in water at rates prescribed locally by mesostructure geometry. The ensuing midplane contraction is coupled to the formation of encoded curvatures. We propose an inverse design tool based on a data-driven model for unit cells’ temporal responses. AU - Guseinov, Ruslan AU - McMahan, Connor AU - Perez Rodriguez, Jesus AU - Daraio, Chiara AU - Bickel, Bernd ID - 7262 JF - Nature Communications KW - Design KW - Synthesis and processing KW - Mechanical engineering KW - Polymers SN - 2041-1723 TI - Programming temporal morphing of self-actuated shells VL - 11 ER - TY - DATA AU - Guseinov, Ruslan ID - 7154 TI - Supplementary data for "Programming temporal morphing of self-actuated shells" ER - TY - CONF AB - We present a computational approach for designing CurveUps, curvy shells that form from an initially flat state. They consist of small rigid tiles that are tightly held together by two pre-stretched elastic sheets attached to them. Our method allows the realization of smooth, doubly curved surfaces that can be fabricated as a flat piece. Once released, the restoring forces of the pre-stretched sheets support the object to take shape in 3D. CurveUps are structurally stable in their target configuration. The design process starts with a target surface. Our method generates a tile layout in 2D and optimizes the distribution, shape, and attachment areas of the tiles to obtain a configuration that is fabricable and in which the curved up state closely matches the target. Our approach is based on an efficient approximate model and a local optimization strategy for an otherwise intractable nonlinear optimization problem. We demonstrate the effectiveness of our approach for a wide range of shapes, all realized as physical prototypes. AU - Guseinov, Ruslan AU - Miguel, Eder AU - Bickel, Bernd ID - 1001 IS - 4 TI - CurveUps: Shaping objects from flat plates with tension-actuated curvature VL - 36 ER -