Aaron Sprecher

Existing digital manufacturing methods can be broadly divided into subtractive approaches, where material is removed from a bulk to reveal the desired form, and additive methods, in which material is introduced voxel-by-voxel to create an object. We here show a fundamentally different method for the fabrication of three-dimensional objects that is neither subtractive nor additive. Instead of removal or layer-by-layer material deposition, in LiquiFab we shape an entire volume of liquid polymer by subjecting it to a set of geometrical constraints under conditions of weightlessness. The physics of liquid interfaces then drives the polymer to naturally adopt a configuration that minimizes its surface energy. On Earth, we achieve weightlessness through neutral buoyancy, and show that a small, well-defined set of boundary surfaces can be used to drive the liquid into a desired form that is then solidified. By sequentially applying this process, complex architectures can be assembled from successive liquid-formed elements. Unlike additive manufacturing, where every point within the object must be individually visited by a print head or light field, LiquiFab forms the entire structure simultaneously. This makes the process highly scalable and opens the door to rapid manufacturing of large objects both on Earth and in space.

Three-dimensional printing of cementitious materials for construction has been extensively investigated in recent years, with several demonstration projects successfully carried out. These efforts aim to leverage the printing process to achieve more efficient production of components compared to conventional concrete technologies. This includes both the process itself (eliminating the formwork stage) and the flexibility in producing complexly shaped elements. To maximize the potential of 3D printing in the construction industry, additional steps must be taken, grounded in a holistic view of the entire process. This involves integration of the production chain, including design, materials, and manufacturing of components, to create elements with optimal performance, encompassing structural, environmental, and architectural aspects. Such multi-functionality requires the viewing of 3D printing not just as a production technology but as a platform enabling the integration of all these components. To advance this approach, quantitative tools are developed to optimize the following three key components: material composition; manufacturing parameters to ensure buildability; and design tools to optimize multiple performance criteria, particularly structural and architectural shape. A demonstration component, namely a post-tensioned beam, featuring two multi-functional characteristics—structural and architectural—is designed, produced, and evaluated. The scientific concepts and research tools used to develop these quantitative design tools are multidisciplinary, including rheological characterization, control of the internal structure and composition of granular materials, simulation of the mechanical behavior of green material during printing, and the hardened properties of the components, all utilizing structural optimization to enhance performance.

The Eastern Mediterranean and Middle East (EMME) region hosts some of the world’s most influential and troubled cities. It is also a hotspot of climate change and socio-economic and political turbulence, which inflate the already flammable conditions and reinforce existing local vulnerabilities. Some of the most arduous challenges of cities relate to the built environment – although vital for human well-being, buildings rarely offer both sufficient and affordable shelter to their inhabitants. With energy performance regulations coming into effect during the past three decades, a considerable proportion of the worldwide building stock had already been constructed and is now ageing and inefficient. Harmonising the energy performance of buildings at a sufficient level requires common objectives and priorities, and the EMME region consists of nations with different governance and regulations. Scarce literature exists on the existing operational frameworks, and this study aims to offer an overview of the built environment policy scene in the EMME region, identifying gaps, good practices and prospects. The study draws from scholarly literature, national and international regulations and other document sources, as well as local experts. This work finds that although most EMME countries participate in and embrace international agreements, they act individually and not collectively, confirming our hypothesis that the policy agenda reflects the diverse characteristics of the region. By recognising standing failings and strengths, moving forward becomes a possibility through the adoption of integrated governance, common policy agendas and financing mechanisms to create sustainable urban centres inhabited by resilient and equitable communities.

Recent advances in machine learning have enabled computers to converse with humans meaningfully. In this study, we propose using this technology to facilitate design conversations in large-scale urban development projects by creating chatbot systems that can automate and streamline information exchange between stakeholders and designers. To this end, we developed and evaluated a proof-of-concept chatbot system that can perform design conversations on a specific construction project and convert those conversations into a list of requirements. Next, in an experiment with 56 participants, we compared the chatbot system to a regular online survey, focusing on user satisfaction and the quality and quantity of collected information. The results revealed that, with regard to user satisfaction, the participants preferred the chatbot experience to a regular survey. However, we found that chatbot conversations produced more data than the survey, with a similar rate of novel ideas but fewer themes. Our findings provide robust evidence that chatbots can be effectively used for design discussions in large-scale design projects and offer a user-friendly experience that can help to engage people in the design process. Based on this evidence, by providing a space for meaningful conversations between stakeholders and expanding the reach of design projects, the use of chatbot systems in interactive design systems can potentially improve design processes and their outcomes.

In the past decade, additive manufacturing processes have exhibited immense potential by pushing the boundaries of material exploration. Involving the construction of volumetric objects through adding flat knitting machines has gained recognition as an additive manufacturing technology since they possess the unique capability to directly fabricate three-dimensional articles from yarn. Nevertheless, while flat knitting machines have made significant strides in the production of three-dimensional textiles, they still face hurdles in handling intricate structures, achieving large-scale production, and accommodating a wide range of yarns. This article proposes crochet as a feasible substitute for knitting in multi-scale applications, owing to its inherent ability to create seamless three-dimensional shells. Despite recent progress in computing crochet instructions, the absence of a digital fabrication technique for volumetric crochet within the framework of additive manufacturing remains a notable gap. This paper provides a thorough examination of the recent advances in computational crochet design tools. It then proceeds to analyze crocheting hand gestures and toolpaths to identify the pertinent design characteristics for a novel technology. Lastly, the paper introduces a pioneering digital fabrication device specifically designed for robotic crochet frameworks. This device underscores the notable advantages of crochet in comparison to other related fabrication methods.

Architectural design decisions are primarily made through an interaction between an architect and a client during the conceptual design phase. However, in larger-scale public architecture projects, the client is frequently represented by a community that embraces numerous stakeholders. The scale, social diversity, and political layers of such collective clients make their interaction with architects challenging. A solution to address this challenge is using new information technologies that automate design interactions on an urban scale through crowdsourcing and artificial intelligence technologies. However, since such technologies have not yet been applied and tested in field conditions, it remains unknown how communities interact with such systems and whether useful concept designs can be produced in this way. To fill this gap in the literature, this paper reports the results of a case study architecture project where a novel crowdsourcing system was used to automate interactions with a community. The results of both quantitative and qualitative analyses revealed the effectiveness of our approach, which resulted in high-level stakeholder satisfaction and yielded conceptual designs that better reflect stakeholders’ preferences. Along with identifying opportunities for using advanced technologies to automate design interactions in the concept design phase, we also highlight the challenges of such technologies, thus warranting future research.

The past decade has seen a growing interest in the use of textiles in architecture, driven by advancements in digital knitting technology. However, while digital knitting machines have enabled the creation of 3D-shaped textiles, they still face limitations in terms of handling complex topologies, output scale, and material thickness. This study proposes crochet as an alternative to knitting in large-scale applications due to its ability to create seamless 3D shells. Although there have been significant advances in the computation of crochet instructions, placing it within the context of additive manufacturing, a digital fabrication method for volumetric crochet is still lacking. This paper offers a comprehensive overview of the recent history of computational tools utilized in fabricating continuous yarned 3D textiles together with an in-depth comparison to reveal the significant differences between knitting and crochet. It then proceeds to identify the relevant design attributes for a novel technology by analyzing hand gestures and toolpaths. Finally, the paper presents a novel digital fabrication device designed for large-scale crochet frameworks, which highlights the considerable advantages of crochet over other related fabrication methods. The proposed robotic device employs patented technology, which enables unprecedented fabrication capabilities in the field and opens new prospects for incorporating large-scale textiles in architecture.

In this paper, we outline a computational framework to capture an intricate relationship between tangible and intangible cultural heritage-architecture and the multiple narratives pertaining to it, to unfold multiple histories as a means for a deeper, more comprehensive preservation of contextual heritage. Deploying a set of digital and computational tools, we present a cross-disciplinary method to produce environments infused with history, and at times overlapping narratives. The framework presented here aims to combine text and spatial data, using both Natural Language Processing and Semantic Segmentation, towards integrating seemingly divided epistemologies of heritage. We ask how we can use computation to enrich current cultural practices and what is at stake in deploying such tools. To explore these questions, we discuss a case study of Wadi Salib, an historical and conflicted neighbourhood in Haifa, Israel, and attempt to assess our framework's ability to render a historical tour through this multi-layered site. Finally, the paper identifies several pitfalls and key challenges for future research.