In various engineering fields it is required to design material layouts with improved performance or tai- lored properties. Hereby, the structural integrity should not be compromised, such that material failure is avoided. Topology optimization enables the systematic design of structures presenting enhanced performance with respect to criteria, such as mass, volume, stiffness, or eigenfrequencies. In the majority of research works in topology optimization, material failure is addressed by constraining or minimizing the stress state in simplified analyses, in which the material is modeled as isotropic linear elastic. However, brittle and quasi-brittle materials, such as concrete and rock, progressively degrade on a micro-scale, before material rupture occurs macroscopically. Using continuum damage mechan- ics, the state of material degradation may be modeled through one or multiple internal variables that are thermodynamically irreversible. However, modeling damage leads to a computationally intensive, non-linear and path-dependent optimization problem. The limited previous research suggests, though, that accounting for material degradation throughout the design phase can significantly improve the per- formance and reliability of the resulting designs. In this work, a level set-based topology optimization approach is proposed to generate steel- reinforced concrete layouts with enhanced damage resistance. Additionally, a thorough comparison of addressing material failure in a linear stress-based and a non-linear damage-based TO approach is conducted. The geometry of the designs is represented implicitly through a level set function. The level set and state fields are discretized using the extended finite element method, which alleviates the need to remesh in each optimization iteration. Assuming isotropic damage, strain softening degradation in the concrete material is modeled through a single scalar damage variable. The steel as well as the un- damaged concrete are modeled as isotropic linear elastic materials. To avoid instability and localization of deformation, non-locality is introduced through a gradient-enhanced damage model. Boundary and interface conditions are imposed weakly using Nitsche’s method. Numerical instabilities due to small material subdomains are mitigated through face-oriented ghost stabilization. The optimization prob- lems are solved through mathematical programming using the globally convergent method of moving asymptotes. Accounting for the irreversibility of damage, the required shape-sensitivities are evaluated semi-analytically through an adjoint approach. The proposed optimization approach is applied to two-dimensional numerical problems from the literature. The results show that resorting to a simplified linear analysis is insufficient to generate struc- turally reliable designs of brittle material. When modeling the non-linear damaged material behavior throughout the optimization process, though, resulting layouts show an enhanced load-bearing capacity and resistance to damage. It is further demonstrated that the maximum damage level in steel-reinforced concrete layouts can be controlled, through an optimized distribution of reinforcing steel material.

The main focus of this thesis is on a thin glass sandwich panel combined with a three-dimensional printed core pattern. The core pattern provides stiffness to the panel, but it also influences the daylight transmission. The goal of this research is to design a façade system which can dynamically improve the daylight performance, effectively control the illuminance inside the building together with preventing disturbing glare.

The research first evaluates the theory behind thin glass, the structural sandwich structure and how the design of a façade panel correlates with its visual comfort. The properties of existing dynamic systems are evaluated, together with exploring other possible dynamic systems that can be integrated in the panel.

The resulting system, a hexagonal core pattern with integrated inflatables, is evaluated on its structural performance and daylight performance using analyses executed in the grasshopper model. This is further expanded by studying the structural performance of more complex core geometry using Diana Finite Element analyses. From the results of these evaluations, a design strategy is created which is able to find the optimal properties of the inflatable façade system.

This design strategy is then applied to a case study, to show both the design of a single façade panel, as well as the full façade system of the whole building. The final result is the design strategy for the dynamic inflatable façade system.

This thesis project was carried out as a part of Ultrapersonalised Products & Services (nextUPPS.nl) as a collaboration between TU Delft and Bata Industrials B.V. To integrate new technologies of Industry 4.0 to enhance product and user experience, Bata Industrials, with a facility in Best, Netherlands, partnered with nextUPPS. An opportunity was identified to implement mass personalization of inlay soles by leveraging emerging technologies such as 3D scanning and 3D printing.

During this project, extensive literature research was conducted into the biomechanics of feet, the factors influencing the design of inlay soles and shoes, and advancements in 3D printing. State-of-the-art technologies and methodologies for personalized footwear, with a focus on orthotics, were also explored. Insights were gathered from experts in orthotics and inlay sole manufacturing. Additionally, data regarding dynamic plantar pressure during various activities and 3D scanning under different loads and postures were collected for subsequent analysis. Observations were made on this data to understand foot behavior, which helped filter relevant parameters for inlay sole development. Based on the research findings, a comprehensive list of requirements was formulated, encompassing all the gathered data that the inlay sole needed to adhere to.

Fused Deposition Modeling (FDM) 3D printing of Thermoplastic polyurethane (TPU) was identified as a viable and cost-effective approach for manufacturing inlay soles. To investigate this, experiments were conducted involving the mechanical testing of samples with different lattice sizes and various TPU variants, aiming to optimize 3D printing materials and parameters. The potential for multi-material printing was also explored during these experiments.

Using the insights gleaned from these efforts, a 3D-printable inlay sole was meticulously designed. Its internal structure featured a field-driven variable gyroid lattice pattern, informed by peak pressure pedobarographic data collected during walking. The shape of the inlay sole was derived from 3D scans of the user’s feet. Multiple iterations were undertaken, incorporating user feedback, prototyping, and expert interviews to refine its design.

A prototype shell shoe was created specifically to evaluate the performance of the newly developed inlay sole with users. Pressure measurements and interviews were conducted comparing the new design to the conventional one. The test results confirm the design’s effectiveness and underscore the importance of personalization in the inlay sole.

The conclusive insole design, along with the corresponding workflow, as well as recommendations for forthcoming actions, equips Bata to potentially launch and market the production of personalized inlay soles for their safety shoes in the future.

This project was focused on designing and prototyping a mobile robotic builder using additive manufacturing. This robotic builder is meant to be a part of a larger fleet of robotic builders that use swarm based strategies to build structures using simple behavioral rules. The concept was inspired by the biological phenomenon that are termites, whom are able to build large mounds with complex structures and architecture on the inside without having a centralized control unit. Separate agents that are able to efficient and effectively collaborate.
The project focused on designing a singular robotic builder for that context. The builder is supposed to be mobile, compact and able to climb its own structures. The builder was also supposed to utilize fused deposition modeling (FDM) printing as its main method of building, mimicking the depositioning of dirt by a termite.
Various brainstorm theories and processes were used to conceptualize different form factors of the robotic builder. All of the concepts were evaluated using standarized methods and further developed.
The final proposed design consists of two main components, the mobile platform and the 3D printer. The design incorporates a SCARA robotic arm for the 3D printing as it has many good properties that fit the context of the project while remaining relative simple in terms of kinematics. The mobile platform includes a whegs system to be able to climb its own printed structures and a leveling mechanism to be able to print in various orientations. The mobile platform was not further developed.
Iterations of the SCARA design were done using CAD software to reduce the development time. After evaluation, a final design was chosen that combined all of the best traits of the previous designs. The design’s main traits were that it was lightweight, simple, bare bones and highly customizable. Relative easy assembly was important as the design will be open-source. Off the shelf components were evaluated on its capabilities and integrated into the system as fit.
The final prototype, a SCARA printer, was able to produce promising results. The prototype was able to print faster than regular printers, print stronger structures and still be sufficiently accurate.
Additionally, a voxel based printing strategy was proposed to help improve the print time more and reduce material usage. The voxel-based approach offers the advantage of enabling a system to be fully optimized for its specific voxel requirements. Italsosimplifiedtheprocessandstrategyofusing FDM-printing in a less controlled environment.
The project provides a foundational design for future SCARA printers, paving the way for continued advancements in swarm robotic construction technology. The final SCARA design is highly customizable and adjust- able with firmware that matches those traits.
Although the project lays down a well thought out foundation, a lot more research and work must be done to properly develop a robotic builder that is ready to implement swarm strategies. The most crucial aspects are mobility, leveling and consistency. Additionally, further optimization of the SCARA printer as a whole and its voxel strategy is necessary.

The problem we want to address
AI(Artificial intelligence) is diving into people’s lives as its algorithm continues to iterate. However, the algorithmic and quantitative systems do not seem to access people’s experiences, which always include emotional and qualitative factors. How can an AI system understand people’s feelings? How can an AI system like GANs optimize for meaningful human values, like beauty?

Our approach
In this project, I mainly build two approaches for designers to translate the human experience into GANs. Starting from the exploration of GANs, I investigate their potential chances to “understand” human experience. Then, the qualitative research
on human experience reveals the aesthetic factors influencing people’s feelings
about GANs‘ output. Through the interviews, some pain points from AI product
designers are concluded. Combining the exploration results in those three scopes, I
hypothesize that retraining with the highly-rated images and building new computational models to iterate the factors from the human evaluation can help designers inform the AI system about the human experience. I cooperated with CSE students and proposed two approaches- CURATION APPROACH and ALGORITHMIC
AESTHETIC APPROACH- based on the above assumptions. The build process demonstrates the achievability of the assumptions. In the evaluation part, the retrained images in both methods are rated higher than the original ones. Both approaches are proved to be practical and feasible.

Our result
For the curation approach, all produced models with highly-rated images outperformed the original model. The original model’s score is 0.2. When replacing 500,1000,2985 highly-rated images into the input dataset, their scores increased to 0.245, 0.269, and 0.255. For the algorithmic aesthetic approach, we select three categories of images(coastline, forest/desert, arctic). In each category of images, three factors are selected to improve. Among the nine groups whose corresponding factors are iterated by algorithms, eight groups’ new images are rated higher by people than the original images. The curation and algorithmic aesthetic approaches are verified to help inform AI systems of human experience.

Potential impact
Following the curation and algorithmic approaches, designers can successfully inform GANs about people’s aesthetic evaluation of their images. Using the human experience to improve AI systems is a starting point. It also proves the importance of the human experience for AI and provides a template for designers in all AI fields to inform their AI systems of human experience.

The work presented in this report is an attempt to allow density-based topology optimization algorithms to take into account machining costs when optimizing. To this end, and estimation model for the cost of 2.5-axis CNC milling was developed based on the principles of Design for Manufacturing.
This estimation model was implemented in a generic topology optimization algorithm in five steps of complexity. The behaviour of the model was evaluated at each step by means of a set of experiments, showing how the addition of the cost estimation influences the optimization results.
The most promising results from the experiments are validated with Autodesk Fusion 360, with which the designs were programmed to be machined on a CNC mill. The machining times from this software were used to calculate the actual machining costs and these were compared to the machining costs estimated by the optimizer.
Two formulations of the method were found to be useful for estimating the machining cost of designs. A simple formulation that uses the shape factor and the differentiation between internal and external pockets to estimate the cost resulted in a cost saving of 13% at the expensive of a compliance increase of 9%. The more complex formulation uses multiple pocket domains to evaluate pocket-specific properties. This allowed a more accurate estimation of the costs, but did not result in a better performing optimization. The cost saving was comparable at 12%, but the compliance increased by 16%.
It was concluded that there is a use for both methods. The simple formulation allows to find cheaper designs, but does not allow much control in the cost estimation. The complex formulation however can be used to fine-tune the method for a specific situation, which could enable it to perform better that the simple formulation.

This project explores how 3D printed pneumatic soft actuators can be used to enhance the expressiveness of textiles with alive-like movement. The research begins by studying current literature on shape changing materials and interfaces in order to select the best candidate material to explore during the project. The project then uses a material driven approach to characterize the 3D printed pneumatic textiles for enhancing their performance and ease of fabrication. Based on the characterization, a material concept is created to showcase the material qualities found during the research and to help study the material experience of shape changing interfaces in future research.

As a result of the research, we introduce Textalive: The Animated Textile Toolkit, a fully 3D printed approach to explore shape changing interfaces and alive-like expressions including its hardware augmented by the computational tool. The toolkit uses accessible 3D printed pneumatic actuators commonly used in soft robotics due to their controllability and ease of fabrication compared to other shape changing materials. The 3D printed pneumatic actuators can be arranged along a 3D printed textile composite to create a variety of shape morphologies. The hardware allows the user to control the kinetic parameters of the movement of the textile to create different expressions. Additionally, the computational design tool allows the designer to predict the shape and movement of the textile by digitally varying the location of the actuator. The toolkit was validated with various designers ranging from different levels of expertise with smart materials showing its potential as a design tool for easily exploring shape changing interfaces and alive-like expressions.

Bistable vibration energy harvesters are an interesting alternative to their linear counterparts. They allow for large amplitude oscillations between their stable equilibria, from which much energy can be generated. However, the stable equilibria are separated by a potential energy barrier that has to be overcome. Therefore, we cannot guarantee these oscillations, and the performance advantage diminishes. As a solution to this, a novel method of stiffness compensation in compliant bistable mechanisms is explored to lower the potential barrier. This method makes use of interaction between the buckling modes. Whereas this phenomenon is most undesired in structures due to their increasing proneness to catastrophic failure, we cleverly use it to our advantage. During the deflection required for the large amplitude oscillations, a transition between these buckling modes occurs, causing the increase in potential energy. By bringing the corresponding buckling loads closer together, the transition is eased and the potential barrier is lowered. An analytical framework was set up as a fundamental test of this method. Using a discrete analytical model of a bistable buckled four-bar linkage with torsion springs, it was shown that the potential barrier can be flattened upon matching the first two critical buckling loads, resulting in static balancing. This was achieved by making two torsion springs three times stiffer with respect to the other two springs. To put theory into practice, three compliant mechanisms were designed using the ratio between the first two buckling loads. Their force-deflection characteristics were experimentally determined and it was shown that the stiffness may be tuned according to the ratio between the buckling loads. Furthermore, it was shown that in designs having the first two buckling loads equal to each other, near zero stiffness is achieved. Hence, this method is proven a successful addition to the arsenal of methods in stiffness compensation and static balancing of compliant mechanisms.

Complex structural shapes can be produced with additive manufacturing. The geometrical complexity that can be achieved translates into an increase in possible designs. Designing these structures with traditional methods is difficult. A design process with computational optimization will enable engineers to use the geometrical freedom offered by these manufacturing methods. This study explores how topology optimization can be used to design structures that are fatigue tolerant. Two optimization algorithms for fatigue tolerance were developed in this thesis. One algorithm minimizes the stress intensity factor, whereas the other one maximizes the fatigue crack growth life. Both algorithms use a resource constraint to limit the total amount of material, an enriched finite element method to analyze the crack growth performance and the method of moving asymptotes to incrementally improve the design. Example problems showed that the algorithm dramatically improves the fatigue resistance.

The main objective of this graduation was to design a sustainable hand cart product concept for young families in the Netherlands, which is simple in its design, easy to use, and affordably priced. The hand cart should furthermore be suitable for up to three children to sit in and suitable to transport goods. Research was done on current hand carts on the market, on users' experiences with them, and on the current sustainability and circularity of Greentom's currently produced product. This research resulted in a list of users' needs and wishes in a hand cart, including the ideal dimensions, needed safety norms, needed requirements for it to be easy to use, and the selling price preferred to be under €250. Furthermore, the research concluded that rPP and rPET are the most suitable and sustainable materials to be used in the hand cart chassis and textile respectively, and that an end-of-life scenario where new Greentom products are sent back and refurbished into 2nd-life products would result in hand carts with 62% lower eco-costs and 71%€ value capture compared to the product with a linear incineration end-of-life. By using these concluded required elements of a hand cart, and by defining the Greentom form family and future hand cart style, several ideas were developed after which five product ideas were proposed. The five ideas showed promising iterations on the basic frame structure, folding principle, push/pull bar design, and bottom design. By detailing their ergonomic and constructional aspects, which concluded the exact dimensions, necessary wheel types, push/pull bar positioning, weight-support beam construction, and necessary folding structure iterations, the ideas were concretized into three concepts: 'Horizontals', 'Twofold', and 'Diagonal'. The concepts were evaluated based on three main criteria from the list of requirements, after which the 'Diagonal' was concluded to be the most promising concept to be further developed into detail. Detailing the concept was done by defining the to-be-improved points with a structural mock-up model, and by defining and further developing satisfier and exciter attributes to ensure a high degree of customer satisfaction using the KANO model. Lastly, after building a 1:1 functional prototype of the improved final concept, the prototype was evaluated by means of a user test, and showed to successfully satisfy all users' needs and wishes with positive reactions on all attributes. The final design, the 'Greentom Go' concludes to be 1) simple in its design since it complies with Greentom's form family style while also expressing its own Hand Cart style, 2) easy to use as it is easily (un)foldable, enables children to independently step in and out of the hand cart, allows attachment of Greentom accessories and a baby car seat, and is well manoeuvrable by having large wheels, a pushable handlebar, and by being lightweight (7.57kg), and 3) affordable since the reuse of existing and future moulds as well as the refurbishment end-of-life scenario allows for lower total costs enabling a selling price of €220. Therefore, the stated design goal is concluded to be successfully achieved by the Greentom Go.

A LIGHT WEIGHT AND COMFORTABLE AIRCRAFT SEAT.
This assignment started fairly broad with only a clear deadline to present a final prototype at the Aircraft Interiors Expo in Hamburg between 11th and 12th of April 2018. At first the project sounded almost impossible to complete before this time. After discussing the possibilities with Rik Westerink, the starting point was to design an aircraft seat feature for the premium economy class combining manufacturing techniques offered by Aeroworks. This is the reason why the report will start with an initial company and market analysis.

BASED ON ACADEMIC RESEARCH.
Personally I rarely encounter comfort issues on an aircraft. I can sit and sleep comfortably almost anywhere. I guess I am lucky like that. Therefore extensive literature research is conducted to truly understand the elements and developments of comfort and utilize this as an inspirational tool for designing a comfortable aircraft seat for all passengers.

HUMAN, BUSINESS AND TECHNOLOGY.
The project initiated with the company and market analysis, with contributions by literature research on comfort allowed for new ideas to emerge which are processed into an advanced premium economy seat pan concept. By means of prototyping this concept I had the opportunity to conduct user testing at the Aircraft Interiors Expo in Hamburg and share my results for the benefit of improving aircraft seating comfort for a large range of passengers.
Hence, what you may expect from this thesis report is a story about my process from the beginning to the end. The result is a research based design development for a low cost aircraft seat pan concept with comfort features tailored to the economy plus and premium economy class for commercial flights.

This report contains the entire process of the graduation project of the Industrial Design Engineering master, Integrated Product Design at the TU Delft. This project is a cooperation between me, Emmylou Hoppe, and the company CrossGuard and the TU Delft. The goal of this project was to gain knowledge about current shin protection in use during field hockey and apply this together with design and production techniques used at CrossGuard. The result is a superior ergonomic redesign of the current shin guards including a new part: the knee pad.The report has six phases; the introduction is a dive into the assignment and its context; the analysis is a closer look at the sport, its players and the market; the design brief in which all the data is interpreted and translated into usable criteria for the design; the synthesis is a combination of the ideation and conceptualisation phase in which the conclusions are applied in a design; the embodiment explores the chosen concept and details all aspects of the concept; and finally the reflection looks back at the process, progress and goals set in the beginning. During the introduction, the focus was on exploring the scope of the project. Finding a good place to begin and exploring the context of the assignment. At the end, specific project and personal goals were set and a planning was formulated to guide the process towards success.The analysis phase consisted of research into all aspects of the project. The goal was to be able to answer most of the research questions at the end of it. First the leg physicality was researched, finding weak spots and studying the geometry using 3d scanning. Secondly the target group was set and researched, using questionnaires and interviews. This concluded in a clear vision of what the consumer wants. The interaction with the current products and the current products themselves were benchmarked based on predefined aspects and tested for their efficiency in those aspects. Lastly the current sizing system was researched and a new sizing system was advised based on gained insights of the physiology and 3d scans.To conclude the analysis phase and to provide a guideline for the project the design brief was formulated using a vision: The shin guard should feel like a indestructible second skin. Protecting the sensitive areas, while not obstructing any movement nor causing any discomfort. And a challenge: To design a shin guard that provides the highest possible protection for the lower leg with modular options for specific situations, without compromising comfort nor maneuverability. In the design brief the criteria to validate the product are also set out, together with trends in this specific scope that can inform design decisions.The synthesis phase is the combination of the ideation and conceptualisation phase in which the found data will be applied towards a shin guard redesign. Rapid prototyping techniques to iterate between working on paper and having a physical prototype to try out were valuable to the success of this project. It allowed the combining of separately used solutions from different applications towards a single concept in the end. The final concept was chosen from a set of three, with a different focus point which their designs build on.The final phase in the design was the embodiment of the chosen concept into a product, the Ergo Pro shin & knee guard, looking at production techniques, material solutions and building a functioning prototype were central to this chapter. To validate the success of the Ergo Pro, it was benchmarked against existing solutions, tested with a regular player and an interview with an expert user was performed. The conclusions and improvement points were written down. A small roadmap for the company on how to introduce this product into the current market marks the end of this project.The reflection looks back at the process and the success of the final product, seeing if there are aspects that need more attention or if mistakes were made. Any other notes about the project will be made here as well.In the end the prototype testing validated the concept and the Ergo Pro shin & knee guard is a feasible product, which meets the goals and criteria set in the earlier chapters.