In this thesis, support structures of a polymer powder based process called XXXXXXXX™ are examined. These structures are crucial for most additive manufacturing processes. The effects of several factors on five industrially important characteristics of support structures are examined by use of the Design of Experiment (DoE) method. It describes the planning as well as the analysis of the experiments. The experiments are planned in a fractional factorial 211-5 design with 64 specimens, resulting in a resolution of IV. The analysis of the data is done by use of the ANOVA method, with which the significance of effects and interaction effects are checked. / I detta examensarbete undersöks stödstrukturer för en polymer-pulverbaserad process kallad XXXXXXXX. Dessa strukturer är väsentliga för de flesta aditiv tillverkning. Med hjälp av metoden "Design of Experiment" (DoE) undersöks effekten av flera faktorer på fem industriellt viktiga egenskaper för stödstrukturer. DoE beskriver både planeringen och analysen av experiment. Experimenten planeras i en fraktionerad faktoriell 211-5 design med 64 provexemplar vilket resulterar i en upplösning av IV. Dataanalysen genomförs med hjälp av ANOVA-metoden, med vilken signifikansen av effekter och interaktionseffekter kan undersökas.

This design thesis is an assessment of the tectonic capabilities and applications of large format 3D printing, given the current available and practiced technologies. This review consists of an analysis of the technical specifications and limitations of the various forms and methods of 3D printing at all scales, followed by an in-depth analysis of technologies that have been adopted and employed at an architectural scale. A number of case studies are assessed to create a typology of tectonic types created by employing 3D printing technologies. These tectonic types: Holistic/Homogenous, Complementary/Integrative, Structural, and Sculptural are then tested to see how they can be incorporated into the design process. This study culminates in a design project that utilizes these technologies and tectonic types in a higher educational facility focused on fabrication and continued research into 3D printed construction. The design acts as a prototypical model for the implementation of 3D printed technologies into the design and construction process, specifically focused on educational institutions on existing campuses. Advancements in this technology and strategies of application have yielded enough capabilities for this design assessment to be formed.

The ongoing energy and environmental crises have pushed the transportation sector, a major greenhouse gas emitter, to seek sustainable fuel and technology alternatives. Natural gas and bio-methane are potential alternatives with numerous advantages over conventional fuels. Adsorbed natural gas (ANG) technology uses porous adsorbent material to store methane efficiently at lower pressures. An issue limiting this technology is the lack of compact tanks with efficient adsorbent packing that increase storage capacity. This study addresses the need for more compact ANG tanks by creating novel binder-less monolithic activated carbon monolith adsorbents with targeted porosity. A template is produced using 3D printing and a commercially available phenolic resin as a filling material. Upon thermal treatment, the 3D-printed template combusts with molecular oxygen in its structure, and the resin is transformed into activated carbon by pyrolysis. Longer activation times led to higher BET surface areas. However, after activation periods beyond 15 minutes, the surface area increase is obtained at the expense of a higher burn-off, which affects the material density. Adsorption of 0.04g/g of methane was measured at 30 bar and 298 K on the activated carbon monolith with the highest BET surface area (516 m2/g). Results in the same conditions on a super high surface area Maxsorb activated carbon were 0.13g/g. Although the methane capacity obtained is lower than in a commercial sample, it was demonstrated that producing an activated carbon monolith with tailored porosity is possible. New techniques for activation should be studied to enhance their gravimetric capacity to make ANG competitive.

This work aims to implement 3D microstructures that generate light with orbital angular momentum towards applications in Biophotonics. Over the past few decades, 3D printing has established itself as the most versatile technology with effortless adaptability. Parallel to this, the concept of miniaturiza tion has seen tremendous growth irrespective of the field and has become an estab lished trend motivated by the need for compact, portable and multi-function devices. Therefore, when these two concepts get together, i.e., 3D printing of miniaturized objects, it could lead to an exciting path with endless opportunities. When it comes to optics, miniaturized 3D printing offers the potential to create compact optical micro-systems and exhibits a way to manufacture freeform µ-optics. In particular, two-photon lithography (TPL) is a cutting edge 3D printing technology that has re cently demonstrated groundbreaking solutions for optics as it offers high resolution with a great degree of flexibility. With a TPL 3D printer, it is possible to fabricate complex µ-optical elements and employ them for compelling applications. In recent years, light with orbital angular momentum (OAM), or ”twisted” light, has captured the interests of several researchers due to its inspiring applications. Tra ditionally, to generate OAM beams, one would require bulk, table-top optics, restrict ing their applications to over-the-table setup. An alternative approach of OAM beam generation is through µ-structures over the fiber, as they can open up new opportu nities, especially in Bioscience, and facilitate in-vivo operations. In particular, this probe-like setup can be used for processes such as optical trapping, high-resolution microscopy, etc. Hence, I propose the development of a novel approach with un precedented capabilities for generating OAM beams right from single-mode optical fibers, by transforming its Gaussian-like output beam by using complex 3D printed microstructures. In this document, I will showcase designs and results on generating Bessel beams (both zeroth- and high-order) and high-NA converging beams (with and without OAM) for optical trapping from the fiber. Remarkably, I achieved the first-ever fiber-based high-order Bessel beam generation and the first-ever fiber optical tweezers with OAM.

Metal Organic Frameworks (MOFs) are a class of porous materials that are predominantly obtained as powders and have been investigated as a solid sorbent for gas separation or carbon capture applications from combustion exhaust gases. The manufacturing of products with MOFs to use them for real life applications is still a major problem. The most common productization method used is to form pellets of the powder MOFs. This has a limitation on the product shape which makes it difficult for it to be used in gas separation applications. This study focuses on using additive manufacturing technique to give MOFs a lattice (mesh-like) geometry which is useful for gas separation applications as the mixture of gases would be able to pass through the lattice structure and be separated due to the inherent MOF properties and characteristics. Two MOFs based on magnesium and manganese salts have been studied in this project. An extrudable paste developed using alginate gel as a binder with these MOFs. With alterations in paste formulations and 3D printer parameters, lattice structures were printed using the two MOFs. CO2 and N2 gas uptakes were measured showing that the structure adsorbs CO2 gas to a higher extend which results in the separation of N2 gas in both materials. When compared to their pristine powder form, other properties of the MOFs such as crystallinity, microstructure, reusability and surface area remain to be preserved after being 3D printed in both cases.

<p>Structures with inherent shape change capabilities enable adaptive, efficient designs without the weight and complexity of external actuators and sensors. Morphing structures are found in nature: plants are able to achieve fast motion without muscular or nervous systems. For example, the Venus flytrap snaps to a closed state with spatially distributed curvatures in less than one second. In contrast, synthetic shape change has been limited by a trade-off between complexity and speed. Shape memory polymers (SMPs) can remember complex shapes, but morphing is slow and one-way. Multistability due to mechanical buckling is fast and reversible, but it has been limited to simple shapes. Furthermore, many examples of biological shape change follow logical patterns with mechanisms that selectively respond to environmental stimuli. This suggests that synthetic morphing structures may also lend themselves to alternative forms of sensing, memory, and logic.</p> <p><br></p> <p>In this research, we introduce a new method of using SMPs in combination with the hierarchical architectures of pre-strained multistable laminates to create switchable multistable structures (SMS). An SMS can remember multiple permanent shapes and reversibly snap between them. We use extrusion-based 3D printing to encode contrasting shape memory-based pre-strain fields in a bilayer. Above the SMP’s glass transition temperature, the SMS becomes compliant and remembers multiple encoded permanent shapes with fast snap-through between them. Below the transition temperature, the SMS regains its stiffness and is fixed in a single state. The geometric freedom of 3D printing enables the design and manufacture of bioinspired structures with complex pre-strain fields and deflections. The developed printing method is applied in multiple subsequent studies, including mechanical pixels, self-folding spring origami structures, and multistable structures printed with thermoset composite inks. </p> <p><br></p> <p>The highly nonlinear behavior of bistable, pre-strained structures makes their design difficult and nonintuitive. Generally, these structures are designed using a slow, iterative process with finite element analysis (FEA). We aim to solve the inverse optimization problem: start with target stable states and solve for the necessary pre-strain distributions. To this end, we develop and implement the switching tunneling method (STM) to design pre-strained,</p> <p>multistable structures. Instead of FEA, we leverage analytical solutions for gradient-based optimization. Tunneling allows for the efficient search of a design space which may contain multiple local and global minima. Switching enables us to take advantage of two different function transformations, depending on if the search is far from or close to a minimum. The STM is validated through FEA and experiments for both conventional and variable</p> <p>pre-strain bistable structures.</p> <p><br></p> <p>Structures designed to react to external conditions or events offer the opportunity to directly integrate sensing, memory, and computation into a structure. This concept is explored using metasheets composed of locally bistable unit cells, which display spatiotemporal mechanical sensing (mechanosensing) and memory. A unit cell consists of a bistable dome with a piezoresistive strip at the base; the resistance indicates the state of the dome. The mechanics of bistability offer inherent filtering and nonlinear signal amplification capabilities, tunable via geometric parameters. Metasheet arrays of these unit cells display distributed sensing capabilities, as well as hierarchical multistability.</p> <p><br></p> <p>We explore the use of time-dependent material properties combined with the mechanics of multistability to encode many unique values within a single mechanosensor unit cell, beyond binary memory. When the piezoresistive material is viscoelastic, cyclic loading causes cumulative changes in both the ground and inverted state resistances. Effectively, the metamaterial is able to count how many times an external force has been applied; this count is stored in the metamaterial’s intrinsic, measurable properties.</p> <p><br></p> <p>This work demonstrates the importance of incorporating memory concepts into structural design, which enables multistability with complex stable shapes, as well as spatiotemporal sensing and memory capabilities. Engineered systems require increasingly adaptive and responsive structures to improve efficiency. The incorporation of inherent memory and sensing enables the complex behaviors needed to interact with unstructured environments</p> <p>and biological features, a pressing issue for aerospace, soft robotics and biomedical devices. The methodology developed here to manufacture, design, and analyze multistable structures advances the state of the art and makes their implementation more practical.</p>

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The primary focus of this thesis is the study of visual development for worldbuilding, starting with creative writing and documentation and translating the written content into visual concepts in both 2D and 3D. This project includes an original narrative, setting, and characters and explores aspects of the visual development pipeline. The content below contains work in visual research, 2D character design, 3D character sculpting, 3D printing and assembly, hard-surface modeling, matte-painting, illustration, compositing, and heavy creative writing.