Making Matter: Small-Scale Biomorphogenic Prototype Based on Ulva-Algae-Biopolymer

Abstract

Recent developments in digital architecture have placed a renewed focus on sustainable architectural materials and the circularity of material systems. Algae has emerged as a promising material for mitigating the effects of climate change due to its ability to absorb large amounts of carbon dioxide. However, the disposal of algal biomass can lead to significant CO₂ emissions and air pollution. The upcycling of algae into composite materials can promote circular economies by reducing the demand for petroleum-based products. In this context, this research explores the potential of Ulva algae in creating 3D-printed architectural prototypes based on bio-algorithm. An experimental analysis of the material properties of algae-based plastic is conducted and compared to similar reference products. This study argues for the importance of designing and fabricating these materials at the required scale while leveraging bio-thinking principles to create closed-loop systems and maximize the potential of natural resources.

1 Introduction

Due to the fast-growing urbanization along with increased climate change impact, the demand for sustainable building materials also continues to grow. In recent years we have witnessed a new emphasis in digital architecture on novel modes of production as well as material computation and circularity. As a result, fabrication techniques and material systems originally not part of the architectural realm can now become an integral part of the design workflow (Gazit 2016) as well as design philosophy (Pasquero and Zaroukas 2016). Accordingly to the essay by Michael Weinstock in the book Systemic Architecture by Poletto and Pasquero (2012), the convergence of architectural forms and practices worldwide can be attributed to various factors, including the interaction of computational systems, the transmission of information through the internet, and the rise of a global rapid transit network. As architects and urban designers navigate the rapidly emerging and complex material world, they find themselves challenged by the intellectual insights and knowledge they must produce, evaluate, and distribute (Pasquero and Zaroukas 2016). In the face of these difficulties, they seek to find a mediating force that can bridge their understanding of the factors present in the interplay between the human and non-human.

Pasquero and Zaroukas (2016) argue that every prototype, in its function as a “weird media,” refracts its inputs by materializing new entities. As a result, the prototype extends the human sensorium and reconstitutes an augmented and transformed agent that is capable of experiencing more than a human subject alone. This is the potential of prototypes functioning as weird media.

In response to these observations, ecologicStudio has developed bio-architectural prototypes that demonstrate this potential. The Urban Algae Folly, for example, is an interactive pavilion that integrates living micro-algal cultures. The effective translucency, color, reflectivity, sound, and productivity of the Folly are the result of the symbiotic relationship between climate, microalgae, humans, and digital control systems (Pasquero and Zaroukas 2016). The H.O.T.U.S project explores the relationship between urban renewable energy and agriculture through a new gardening prototype (Pasquero and Zaroukas 2016), while the Tree.ONE project, exhibited in Hyundai Motor Studio in Busan (EcologicStudio 2022), showcases a “living tree” prototype designed by artificial intelligence and bio-digitally grown with algae-based biopolymers that capture carbon and promote a pollution-free and carbon-neutral environment (Fig. 1).

Fig. 1.

Urban algae folly, H.O.R.T.U.S, Tree.One (Provided by ecologicStudio)

These prototypes are not simply machines, but rather construct an interactive ecology of their own. They bring together human and non-human agents, both organic and inorganic (Barad 2012). The production of knowledge in this context is saturated with human metaphors and images, yet it also bears traces of the inhuman. In this sense, the world becomes an intra-active ecology, and prototypes are seen as apparatuses that construct the categories of human and non-human (Pasquero and Zaroukas 2016).

Algae is acknowledged as one of the most rapidly growing plants on the planet and is seen as a promising material in the efforts to mitigate the effects of climate change. This is due to its ability to absorb a minimum of 10 times the amount of carbon dioxide compared to other plants (Batista et al. 2015). However, due to climate change, for several decades, the coastal seas of a growing number of countries covering many areas of the world have been affected by blooms of algae (Lassus et al. 2015). The Ulva algae booming pollution often affects major coastal cities like Qingdao, China. To remove tonnes of it from beaches in Qingdao, the city's government dispatched thousands of boats and bulldozers in 2021 (Zhang et al. 2019) and transfer the rural areas to dispose (Madejón et al. 2022). The disposal of this material in landfills or by incineration and burial can result in significant CO₂ emissions and air pollution (Castaldi and Melis 2004). This is due to the production of methane, a potent greenhouse gas, from the organic matter in the algae during decomposition in landfills (Chisti 2007), as well as the release of CO₂ and other pollutants from incineration and burial (Sánchez-Martín et al. 2018). To mitigate these environmental impacts, converting the material into composite materials has been suggested, which can reduce the demand for petroleum-based products and promote sustainability (Wang and Wang 2017) (Fig. 2).

Fig. 2.

An excavator removed algae at a coast in Qingdao, China (Image by Dan Hei)

Given the pressing environmental challenges we face, Steven et al. (2020) argues that biodegradable and bio-based plastics offer a promising solution for promoting sustainable growth within the plastic industry and serve as a feasible alternative to petrochemical plastics soon. From an ecological standpoint, these materials exhibit biodegradability and have the capability to sequester carbon dioxide, thereby reducing the carbon footprint associated with a product or structure over its lifecycle (Steven et al. 2020).

Consequently, the present research endeavors to investigate the possibilities of upcycling the material system for architectural prototypes utilizing the recycled Ulva algae. The design is to promote ecological balance and to consider the process of “making matters” as an integral aspect of the design process. From Ulva algae leaf to algae powder, from algae powder to algae-based plastic, and the 3d printable algae filament. We investigate the material properties of algae-based biopolymer through a quantitative experimental analysis and comparison with comparable reference products. Our goal is to explore the relationship between material making, design methodology, and biology by integrating natural organic forms with materials in architectural prototypes. This approach will reveal new design possibilities at various scales, from micro to macro. To achieve this, it is essential to tailor the design and fabrication process to the specific scale required. This is because a “one size fits all” approach is not practical in digital fabrication (Yeang 2008). To evaluate the performance and materiality of algae-based plastic as a building material, we use digital morphology to create 3D-printed prototypes based on human body geometry, serving as the data origin for micro-scale space (Fig. 3).

Fig. 3.

3d printed coral morphological prototype based on algal biopolymer (Author)

This paper argues that the integration of bio-thinking principles in design has significant potential to create closed-loop systems within a circular system, leveraging natural resources such as Ulva algae. The goal is to create an architectural prototype where the storage and reduction of carbon emissions is achieved through a balance of resources taken and returned to the environment.

2 Making Matter: Algae Based Biopolymers

Alva lactuca (sea lettuce), a green edible alga in the Ulvaceae family (Bates 2020), is utilized in food, agriculture, and medicine industries (Groenendijk et al. 2016). However, it also contributes to harmful algal blooms (HABs) in coastal cities such as Qingdao, China. HABs can impact aquatic life, causing difficulty in finding food and population displacement. When transported to rural areas for disposal, such as in landfills or through incineration and burial (Madejón et al. 2022), it results in additional carbon dioxide emissions and air pollution.

This algae plastic is made of carbon that has been drawn from the carbon reservoir of the atmosphere and put into the stock of carbon of our built environment. -Charlotte McCurdy (Hahn 2019).

The use of algae as a platform for bio-polymers production offers direct carbon capture by removing CO₂ from the atmosphere through the photosynthesis process and conversion to various forms in central metabolism (Satyanarayana et al. 2011). Our study focuses on the development of sustainable materials based on algal biomass that capture and consume CO₂ and nutrients. The adoption of this methodology also entails the utilization of otherwise incinerated algae through recycling, resulting in a decrease in carbon emissions, as demonstrated by the project of Tree.One and Otrivin Airlab from the EcologicStudio (2022).

2.1 Material Making Experiments

According to Rahman and Miller (2017), four methods exist for converting algae into bioplastics: direct conversion, genetic engineering, blending with petroleum, and blending with bioplastics. The use of biological feedstocks can result in plastic with similar performance characteristics as those produced from fossil fuels. However, the observation from us shows that the Ulva Lactuca algae has a potential size of 60 cm, but typically grows to less than 30 cm, making it unsuitable for material composite testing.

Yaradoddi et al. (2016) conducted research on developing biodegradable plastic from waste fruit. In this study, dry Ulva algae was ground into powder and added to the traditional corn starch-based bioplastic production process. The study used a constant set of dosage parameters of potato starch, water, and lemon vinegar for each set of testing samples. The experiment included two control groups, with varying doses of algae powder and the addition of glycerin.

Fig. 4.

Algae plastic making experiment (author)

Fig. 5.

Algae plastic making experiment (author)

The material properties of the algae-based bioplastic were observed, and the results showed that the addition of Ulva algae powder and glycerin significantly impacted the material's properties. The best flatness and malleability of the material were observed with the addition of algae powder in the middle range (Fig. 4). The first control group lacked glycerin and exhibited high brittleness, while the second control group, with glycerin, had a rubber-like softness (Fig. 5). Overall, the addition of Ulva algae and glycerin improved the material's flexibility and quality.

2.2 Algae-Filament Making Process

We harvest carbon dioxide, purify polluted urban air, and 3D print plastic free biodegradable products. Essentially, we convert air pollution into products that help protect our breathing. -Claudia Pasquero and Poletto (2022)

By integrating algorithmic design and 3D printing with algae filaments, the project of Otrivin Air Lab proposes a bio-digital fabrication process using bioplastics and biorubbers to 3D print algae filaments to create the NetiPot as a new line of products that update the historical evolution of nasal cleansing and respiratory wellness. The ecologicStudio designers have developed a new nasal cleaner by rotating the surface with varying angles and rotations. This 3D printed algae-based bottles offers a distinctive grip and rejuvenates the aesthetic view of such cleaners. The material's color deepens with increasing layer thickness, providing excellent waterproofing and strength, even able to bear the weight of an adult. Furthermore, the 3D printed stool made from algae filament shows high support strength in large-scale testing.

The integration of Algae-filaments from Algae-plastic with the cutting-edge 3D printing technology constitutes a pioneering methodology for assessing the physical properties and behavior of algae-based plastic through the lens of data-driven digital morphological analysis. This methodology offers a unique opportunity to experiment with and evaluate the performance of algae-based materials in a controlled, computational environment (Fig. 6).

Fig. 6.

Otrivin Airlab, photo by @NAARO (Provided by ecologicStudio 2022)

In order to create a wider variety and range of products based on discarded Ulva algae, we have decided to customize our own 3D printing filament. This will enable us to test a greater number of material properties based on varying amounts of different types of seaweed additives, and to more flexibly explore the potential for creating a greater diversity of architectural forms. In our experiment on the production of algae-based plastic, we employed various industrial tools such as the FLD-25A filament extruder, an electric heating blasting drying oven, and also introduced dried Ulva algae powder mixed with Biopolymer 4032D (NatureWorks) to generate a 3D printable algae filament. The filament-making process was compartmentalized into three distinct stages, each consisting of 14 procedural steps: material preparation, material blending in accordance with specified ratios, and filament extrusion. Our current efforts in production entailed evaluating the influence of varying three different proportions of algae in biopolymer pellets on filament properties under constant extrusion conditions, including temperature and extrusion speed, as illustrated in the flowchart presented in Figs. 7 and 8.

Comparison of results (Fig. 9) showed that the ratios of algae additions impact the color and visibility of algae impurities. As the amount of algae increases, the material becomes progressively darker and takes on a brownish-green colour. Ensuring that the material base temperature is appropriately set to the standard PLA extruding temperature is crucial in preventing the plastic from being scorched as a result of excessive combustion. Meanwhile extruding the filament too quickly or too slowly can both lead to deformation of the filament and uneven distribution of the seaweed powder. The algae filament was found to be relatively brittle compared to commercially available standard PLA filament. According to Bulota and Budtova (2015), the addition of algae flakes decreased the tensile strength of the material in all cases, from 65 MPa for neat PLA to around 30 MPa at 40 wt% of filler, regardless of the type of algae or particle size. Hence, it is imperative to exercise caution in determining the appropriate quantity of seaweed to be incorporated. Next, we increased the ratio to 3%, but the filament did not form and had an irregular shape (Fig. 9). However, by adding 0.1% plasticizer to the biopolymer, the sample (Fig. 9, far right) became more formable, smoother, and less brittle compared to the previous three.

Fig. 7.

Algal filament making preparation (Author)

Fig. 8.

Algal filament making process (Author)

Fig. 9.

Material properties of algal filaments with 0.1, 0.3, 0.6 and 1 algae ratio (author)

The experiment results were analyzed, leading to several modifications to the material. The drying time of Ulva algae was reduced to 14 days, the melting temperature of the extrusion was lowered to 190 ℃, the toughening agent was maintained at a ratio of 0.1:100, and the algae/biopolymer ratio was increased to 10%. The sample produced (Fig. 10) displayed a green color, similar to Ulva algae, with a smooth surface and a slight matte texture. Additionally, the material's toughness improved compared to previous results.

Fig. 10.

Updated Algal filament (10%) and printing detail of this material (author)

3 Making Matter: 3d Printable Bio-Morphological Prototype

Nature is a profuse and ample reservoir of inspiration for innovation, comprising both visual and functional elements. Bio-digital architecture synthesizes biological and digital techniques, seamlessly fusing natural intelligence with computational technology (Estévez and Navarr 2017). Jan Kaplický, who believed that architecture should be inspired by nature and reflect its principles of organic growth, argued that the use of bio-algorithms in architecture can result in structures that are not only functional and efficient but also aesthetically pleasing (Kaplický 2005). Furthermore, the use of bio-algorithms represents a step towards a more dynamic and adaptable form of architecture that can respond to changing environmental and cultural conditions (Deleuze 1990). Additionally, incorporating bio-morphology into architectural prototypes offers the advantage of optimized material use, as the forms and structures in nature are known to be highly efficient and optimized for their intended purpose (Dey and Dutta 2015). The integration of bio-algorithms in architecture does not involve the use of biology as a mere metaphor or the emulation of biological structures. Rather, it involves the incorporation of the algorithmic structure and the logic of spatial interaction, negotiation, and self-organization inherent in these algorithms. The appropriated behaviors from bio-algorithms range from pragmatic rules regarding structural and programmatic adjacencies to abstract behaviors that produce micro to macro scale architectural effects.

Coral reefs provide microenvironments for sea creatures due to their natural colony behavior on sea rocks. This ecosystem can range from small solitary organisms to large colonial islands. The H.O.R.T.U.S. XL Astaxanthin.g project by ecologicStudio is a large-scale, high-resolution 3D printed bio-sculpture that supports both human and non-human life. The substratum morphogenesis is simulated through a digital algorithm that mimics coral colonies (EcologicStudio 2019) (Fig. 11).

Fig. 11.

H.O.R.T.U.S. XL Astaxanthin.g at Centre Pompidou in Paris, France, The algorithmic design technique inspired by the morphogenesis of coral colonies (Provided by EcologicStudio 2019)

The digital algorithm of coral colonies, referred to as recursive growth, has the ability to generate architectural prototypes at various scales to evaluate the behavior and performance of Ulva algae filaments in different functional uses and spatial data. This exploration begins with a microscale spatial data analysis of the human body. The human body geometry is a crucial aspect in bio-digital architecture, serving as a singular source of spatial information and geometry. The digitalization of the human body creates a spatial network such as points data or mesh data linking bio-morphology and biomaterial. This has been emphasized in studies of bio-digital architecture (Kontovourkis et al. 2015), which highlight the potential of using the human body geometry in architectural prototyping and design. The use of 3D printing technology, such as FDM, allows for the quick and efficient fabrication of physical prototypes, enabling designers and engineers to test and refine their designs in a fast and cost-effective manner.

3.1 Design Prototype Generation

In the design of coral morphogenesis, the recursive algorithm is utilized to simulate geometric growth with constant diffusive and recursive features. Recursion, which refers to the recurring phenomenon governed by natural forces, is applied in growth from the molecular level to the cosmos (Dandu 2019). To understand this process, we generate diagrams of the generating process. We test the algorithm’s spatial data and parameters by adjusting the pattern of digital morphogenesis on a single polygon sphere (Radius = 15 cm) through Surface Subdivision (smooth degree and resolution), Curvature Gradient (Magnitude of morphological change diffusion), Curvature Gradient Scale (Density of morphological change diffusion), Iteration (number of model recursions), and Voxel Size (output resolution). For comparison, we set the Volume Velocity, which is based on Perlin noise, at a constant value to determine the direction and degree of twisting and growth (Fig. 12).

Fig. 12.

Morphological generation catalogue based on algorithm of coral growth (author)

The digital simulation of morphology and comparison with reference groups allow us to determine the impact of parameters on morphological growth. Increasing the sphere's subdivision (from 20 to 60) results in increased density and connectivity of branches. Comparing reference groups (rows 2, 3, and 4) shows that reducing the Curvature Gradient enhances diffusion area and resolution, while increasing Gradient scale increases model variation strength. At iteration 35, it becomes impossible to maintain the sphere's basic state.

3.2 Generating Prototype on Human Body

The digital representation of human geometry can be conceptualized as a variable and dynamic polygon surface that is capable of being deciphered. The human body geometry is divided into Catmull-Clark subdivision, and intersections between these planes are assigned with spatial coordinates. Through the implementation of data filtering, specific regions of the human body can be selected and utilized to generate the morphogenesis of coral colonies.

The analysis of the diagram and prototype demonstrates that the human body geometry aligns with the sphere-based simulation logic, but parameters must be adjusted to account for feasibility of fabrication and body fit. The curvature scale should be moderate to prevent over-curvature, and a moderate voxel size and curvature gradient must be set to ensure 3D printing feasibility and prevent excessively thin or dense bifurcations (Figs. 13 and 14).

Fig. 13.

Morphological generation catalogue based on algorithm of coral growth on digital human body geometry (author)

Fig. 14.

Decoded human body mesh geometry integrated with design prototype(author)

3.3 Fabrication (3D printing) Process Based on Ulva Algal Filament

In the final section, the performance of algae-based materials in small-scale human body applications through FDM 3D printing technology (Anycubic Kobra Max) is investigated. The algae-based filament utilized is a synthetic bioplastic with a biological base, thus the printing temperature was set at 195 ℃ to ensure proper melting of the PLA and maintain the properties of the dried seaweed powder (Wang et al. 2009). Other printing parameters, including the printing speed of 50 and the printing bed temperature of 70 ℃, were based on the characteristics of PLA. Multiple print tests were conducted to determine the most efficient and optimal parameters for the fabrication. The final parameters selected, based on surface integrity and efficiency, include the layer height of 0.4mm, the wall layer of 1, the wall thickness of 0.4, the infill density of 7% and the 10% zigzag support (Fig. 15).

Fig. 15.

Fabrication workflow by FDM 3d print technology (author)

In evaluating 3D printed prototypes integrated with human body geometry, the fit to the body surface and comfort achieved through the smoothness of the algae filament are satisfactory. The prototype weight of 340g does not pose a burden. Potential improvements include reducing layer height for improved surface accuracy and adjusting print angle to decrease support density for material efficiency.

The integration of Algal bioplastics with 3D printing has the potential to expand its use in various applications, including wearable devices as mobile energy sources utilizing human carriers as architecture. The precision of 3D printing allows for the creation of customized devices that fit the individual's body shape and needs (Muldoon et al. 2022). Further investigations through extensive experimentation is essential to improve the development of the technology in question. In the realm of digital fabrication, it is imperative to understand that a homogeneous approach is not tenable. As such, designers should adopt a process that involves iterative design and trial of prototypes at various scales, with a view to effectively exploring the spatial attributes of the technology (Fig. 16).

Fig. 16.

Printing details of design prototype (author)

4 Conclusion

In conclusion, this paper posits that incorporating bio-thinking principles into the design process has the potential to promote ecological balance and emphasize the integral role of material making in the design process. Through the utilization of natural resources such as Ulva algae to create biopolymers, the integration of bio-thinking principles into the design process can lead to the development of bio-morphological prototypes that mediate between the human and nonhuman. This, in turn, provides a speculative glimpse into the future of architectural material systems and the potential for closed-loop systems within a circular economies. The resulting architectural prototype not only demonstrates the storage and reduction of carbon emissions, but also highlights the importance of balancing the resources taken from and returned to the environment.