Microalgae cultivation systems face critical challenges in balancing efficiency, scalability, and sustainability. Existing methods, such as open ponds and photobioreactors (PBRs), present inherent limitations—open ponds are low-energy and cost-effective but lack environmental control, while PBRs offer higher efficiency but require significant infrastructure and energy input (Encarnação et al., 2023; Abdur Razzak et al., 2024). This research proposes a living textile system as an intermediate solution, combining the passive functionality of open ponds with the control and efficiency of PBRs, but at a lower cost and with reduced energy demands.
By integrating Scenedesmus sp. microalgae within a hydrogel-based woven structure, this study enhances gas exchange, promotes microalgal attachment, and optimizes photosynthetic efficiency—key challenges in previous systems. Findings reveal that fiber composition and weave structure play a fundamental role in microalgal viability, influencing hydration retention, and resilience against detachment. Additionally, origami-inspired folding mechanisms improve usability, allowing the textile to fold and unfold dynamically for controlled closure during adverse weather conditions and efficient rehydration.
To explore potential applications, this research conceptualized the Living Climate Panel, demonstrating how living textiles can function as an integrated cultivation system that not only supports microalgal growth but also enhances sustainability, improves air quality, and regulates microclimatic conditions in indoor environments. By merging biology, textile engineering, and design, this study redefines textiles as active, self-sustaining systems, rather than passive materials, offering a scalable and adaptable solution for sustainability-driven applications.

Moss covered surfaces are a promising way to mitigate the urban heat island effect. A layer of moss on a building’s façade reduces heat absorption during summer, hence passively cooling the building and its surroundings. The startup Respyre wants to offer such moss layers as a commercial product. A bio-gel mixed with moss fragments is sprayed on a porous concrete outer layer. This is irrigated for several months until the wall is covered by a layer of living moss.

The aim of this project is to rethink the existing irrigation system, since it gives a bad water distribution, resulting in high water usage and uneven moss growth.

First, the context was analysed. Literature study and an interview with an expert provided a better understanding of what role moss has in mitigating the urban heat island effect and what moss needs from a biological perspective. Further research revealed what solutions for providing moist already exist. A stakeholder analysis provided insight into who has something to say about the irrigation system. All these findings together resulted in a list of requirements.

During a brainstorm, a set of ideas was sketched to find as many out-of-the-box solutions as possible. This is a mix of new ideas, existing ideas found during the analysis, and combined ideas.

The brainstormed ideas that are feasible were developed into concepts. They were prototyped and their water distributing performance was tested by irrigating them in a green house. The concepts have been assessed on (among others) water distribution, estimated costs, minimum water pressure, ease of installation, and the need for developing new parts.

Five promising concepts were further developed and tested on a larger prototype. Their water distribution was quantitively tested, and costs estimated.

The finally chosen solution was further improved and detailed in the last stage. The end result is a design and prototype of an irrigation system that gives a slightly more uniform water distribution at a significantly slower rate for comparable costs.

A hard-soft interface refers to the boundary between two materials or regions with significantly different mechanical properties, where one is rigid or hard and the other is flexible or soft. These interfaces are common in both engineered and natural systems and are characterized by the contrast in how each material deforms, transfers loads, or responds to environmental stress. Engineered hard-soft interfaces often experience failure due to high interfacial stresses, poor adhesion, and localized stress concentrations caused by mismatched mechanical properties. An example of engineered hard-soft interfaces can be found in tissue engineering, where they are used to replicate natural transitions between tissues, such as those between bone and cartilage. In contrast, hard-soft interfaces in nature, such as the root-soil system, demonstrate remarkable strength and adaptability, efficiently distributing loads and reducing stress concentrations despite differences in material properties.
The pull-out force was chosen to assess the strength of the root-soil interface, capturing the mechanical interactions of roots with their environment. This study focused on barley and mung bean seeds, chosen for their distinct root structures, barley with a fibrous system and mung bean featuring a taproot system. Over a 15-day growth period, various root characteristics such as length, diameter, tortuosity, and branching patterns were analyzed across soil and hydrogel substrates, each with distinct material properties and stiffness. The methodology included measuring growth in terms of days and stem height, along with 2D root trait extraction to analyze characteristics such as length, diameter and number of branches. Additionally, 3D computed tomography (CT) scanning was used to visualize root architecture, while pull-out tests provided key data on resistance and force-displacement curves, and finite element method (FEM) simulations enabled sensitivity analyses of various root structure configurations in a non-destructive manner. Lastly, experiments with hydrogel tested its viability for root growth, involving detailed protocols for hydrogel composition and seed preparation.
Plant growth measurements revealed a consistent increase in stem height over time, effectively captured by the logistic growth model. Laboratory pullout tests and root extraction demonstrated that increases in root characteristics such as length, diameter, and branching significantly improve pullout force in both barley and mung bean seeds. Moreover, pullout test results showed that barley roots have greater mechanical resistance and higher maximum forces than mung bean roots, although with greater variability in the data. FEM simulations indicated that a 45° vertical branching angle yielded the highest pullout force for barley in soil (5.09 N), while an 80° angle was most effective in hydrogel (4.98 N). In contrast, radial branching angles had negligible effects in both substrates. Tortuous root configurations significantly increased pullout force in soil, nearly doubling it from 5.09 N for straight roots to 9.80 N, but only slightly improved it in hydrogel, from 3.20 N to 3.61 N. The addition of branches in mung beans significantly increased pullout forces in both substrates due to the greater surface area, which enhanced root-substrate interaction. The FEM simulations showed that pullout forces were generally higher in soil due to its rigidity, which leads to a rapid increase in pullout force until root failure. Hydrogel, with its elastic properties, allowed roots to stretch more under load, providing uniform and gradual resistance. The FEM model was also validated through energy history output results and mesh convergence analysis. Lastly, initial experiments growing roots in hydrogel show promise for this substrate as a soil alternative, however further research is required to optimize its properties for plant growth.
Overall, this study provides a better understanding of the factors optimizing root anchorage and interface strength, offering design strategies for bioinspired engineered hard-soft interfaces. It also emphasizes the need to tailor natural design principles to the specific material properties of substrates in engineered contexts.

Coral reef ecosystems are an essential part of the ocean environment and imperative to the health of the entire ocean. With warming oceans, destructive fishing, marine pollution, and other factors, the coral reefs are dying. Losing coral reefs dramatically affects marine biodiversity and negatively impacts food security, shoreline protection, and essential tourism economies in coastal communities. Globally, more than one billion people directly benefit from coral reefs (Souter et al. (eds), 2021).. Therefore, restoring coral reefs is critical to ensure the well-being of both marine and human communities.
This thesis focuses on the redesign of a floating fish breeding system for the coral reef conservation start up, RoffaReefs. RoffaReefs is working on restoring ecosystem through the breeding of reef fish through a first of its kind floating fish breeding system. This system works by allowing fish eggs collected from the reef to grow into larvae in a protected environment before being released back into nature. The overall aim for the redesign was to design a nature-based fish breeding system for improved performance that can be used in various marine contexts.
The proposed design is a modular design with three separate modules: biological, storage, and float. This new design can improve the system’s operator accessibility and scalability in future contexts. Through the testing of scale models, it has been shown to improve the stability of the system in wavy conditions. At the end of this thesis, the next version is ready to be manufactured, and a full-scale test in context can be completed.

Reefs are the most important marine ecosystems that support the majority of marine life in our oceans for both temporary and permanent shelter, refuge and food supply. However, reef ecosystems around the world are disappearing and artificial reef structures are an opportunity to help restore them.

This project contributed to the field of artificial reefs, by designing a surface pattern on both millimeter and centimeter scale, that aims to enhance and support biodiversity on the large concrete “ReefBlocks”, by the company Reefy. That serve as both artificial reefs and as functional infrastructure, such as breakwaters and dams.

In an extensive literature research, information on marine environments was collected and three main types of inhabitants that can be found in reef communities were identified, including only those that interact with hard substrates like the ReefBlock. The three different inhabitant types were distinguished based on their unique role within ecosystems, which they need to grow, stay balanced and provide the necessary ecosystem functions.

To understand the ecological requirements for the pattern design, existing knowledge on increasing biodiversity with artificial reef substrates was researched and summarized in a micro marine spatial plan on the scale of an entire ReefBlock. The addition of crevices and pits of varying sizes on centimeter-scale and grooves on millimeter-scale were concluded as the main crucial design features that need to be reflected by the final pattern design.

A design vision to aim for biomimicry of lobed brain corals was formulated for the aesthetics of the proposed pattern design. As brain coral patterns have a visually organic complexity and flexibility that allows for the natural implementation of the identified crucial design features. In order to achieve the pattern design vision that meets all the collected ecological, stakeholder and production requirements, a design toolset was developed that combines the power of generative art with the power of parametric design.

The generative art tool allows the semi-automatic creation of lobed brain coral patterns in a similar process to how actual brain corals, and many other examples in nature, receive their pattern from, in a so-called reaction-diffusion system.

With the generative art tool, a black and white 2D image is generated, which is then used as the input variable for the parametric tool. Which directly translates the 2D image into a perfect 3D surface pattern. This method ensures that the pattern design always meets the various production requirements.

In order to support the choice for the aesthetically best-rated design by the general public, a survey with 60 respondents was conducted with questions based on the stakeholder requirements.

In order to validate the effectiveness of the pattern design within the timeframe of this project, a six weeks lab test was conducted using concrete prototypes of the pattern design and microalgae. The test showed promising results for meeting the defined ecological requirements.

Lastly, a rubber form liner was produced in order to help Reefy along with future field tests with the proposed pattern design, in order to validate the conclusions and insights gained in this graduation project, and in real marine environments, for a much longer period of time.
The design toolset was initially created to support the iterative design process and helped to quickly try, test and compare a multitude of designs. But in the end, this toolset has proven to be very valuable for future use by Reefy as they plan on extending their product line with smaller-scale wall panels and for potential adjustments to the proposed pattern design based on their field tests.

Flavobacteria are marine organisms that produce vivid, angle-dependent colour as their cells organise into structures that interact with light. These optical structures, resulting in structural colour, are influenced by environmental factors such as temperature and humidity. In this graduation project, the aim was to integrate living Flavobacteria into a flexible, sustainable material, creating labels that communicate environmental signals through changes in the structural colour of the embedded Flavobacteria. Understanding how to maintain Flavobacteria and their structural colour, outside the laboratory can be the steppingstone to make the entry of these microorganisms into the world of design.

The initial phase of the project focused on understanding the requirements for Flavobacteria to make structural colour outside the controlled laboratory environment. This understanding was crucial to design in a way that accommodates the unique characteristics of these microorganisms. Temperature was selected as the primary environmental stimulus to address, given its significant impact on the size and colour of the Flavobacteria colony. Additionally, temperature changes can be transferred through materials and therefore enable a sealed label without the necessity of openings to let environmental stimuli through.

The second phase involved an iterative experimentation process, which aimed to identify a suitable top material of the label that would facilitate the formation of structural colour by Flavobacteria. Additionally, efforts were directed towards finding an appropriate growth medium for Flavobacteria within the living label and devising an activation method that would initiate their growth exclusively during the product’s use phase. The outcomes of this iterative process were then integrated into a vision for the living label.

The project continues by presenting a future vision for the living label and proposing additional guidelines for designing with Flavobacteria. This vision draws upon literature research as well as the findings and insights gained through this graduation project. Further research is recommended regarding the characterization of the temperature influence on Flavobacteria, improving the surface texture of the medium used in the living label

To conclude, by combining existing knowledge with the project’s outcomes, a first proof of concept for a living label is proposed, paving the way for future exploration and application of these living microorganisms in innovative design contexts.