Research Papers


  • Ma, Chun Yu, Jennifer Chan Yan Yu and Kristof Crolla, “Expanding Bending-Active Bamboo Gridshell Structures' Design Solution Space Through Hybrid Assembly Systems”, in A. Globa, J. van Ameijde, A. Fingrut, N. Kim, T.T.S. Lo (eds.), PROJECTIONS - Proceedings of the 26th CAADRIA Conference - Volume 1, The Chinese University of Hong Kong and Online, Hong Kong, 29 March - 1 April 2021, pp. 331-340

    ABSTRACT | This paper discusses the development and testing of a novel design method for the low-tech construction of bending-active bamboo gridshell structures. It expands this typologys current design solution space by combining and building up on two common production methods for light-weight shell structures: 1) the lay-up method, typically used in bamboo architecture in which members are added one at a time, and 2) the flatbed method, in which a prefabricated equidistant flat grid without shear rigidity is propped up and deformed into its final doubly curved shape. The novel methodology expands the systems design solution space by incorporating singularities within the grid topology and by layering multiple separate grids. This allows for spatially radically different building geometries without loss of implementation workflow efficiency. A demonstrator design project, tested through a large-scale prototype model, is described to illustrate the possible spatially engaging architectural design opportunities presented by the novel approach.

  • Goepel, Garvin and Kristof Crolla, “Secret Whispers & Transmogrifications: a case study in online teaching of Augmented Reality technology for collaborative design production”, in A. Globa, J. van Ameijde, A. Fingrut, N. Kim, T.T.S. Lo (eds.), PROJECTIONS - Proceedings of the 26th CAADRIA Conference - Volume 2, The Chinese University of Hong Kong and Online, Hong Kong, 29 March - 1 April 2021, pp. 21-30

    ABSTRACT | This paper focusses on teaching the integration of Augmented (AR) and Mixed Reality (MR), combined referred to as Extended-Reality (XR), and photogrammetry technology into handicraft using an online-taught digital fabrication workshop as an educational case study. Set up in response to restrictions from Covid-19, workshop 'Secret Whispers & Transmogrifications' had students and instructors around the world participate in a course that challenged our understanding of educating craft and technology without the necessity of physical presence. The integration of AR into craftsmanship enhances architectural design and fabrication processes as it overlays computation-driven information onto the hands of the end user. These computer-numerically-controlled workflows incorporate and rely on manual actions as an integral part of a process that is typified by inevitable, unpredictable, human error. In doing so, the workshop questions common infatuation with precision in digital fabrication and construction by striving for alternative approaches that embrace the inaccuracies and imprecisions innate to technologically-augmented human craftsmanship. Participants took part in a hands-on clay modelling 'secret whispers' experiment that was designed to introduce theoretical concepts and applications of XR technology into the production workflows. This paper concludes by highlighting that the accessibility of today's technology enables AR-enhanced craftsmanship to be successfully taught remotely and online.

  • Dr Alecs Kak Tien Chong, Dr John Chen, Mike Tapley and Kristof Crolla, “Creating Parametric Design Workflows for Rapid Conceptual Design and Optioneering”, IABSE Congress – Resilient technologies for sustainable infrastructure, February 3-5, 2021, Christchurch, New Zealand

    ABSTRACT | Complex, large span structures including roofs and footbridges are functional structures and are often presented as works of art or sculpture to complement the surrounding landscape. The design process of architectural large span structures or footbridges require architects and engineers to collaborate closely to co-create visually appealing and structurally efficient forms that serve the aesthetic, functional and economical objectives. In the co-creation process, a rapid turnaround is often expected. However, a tool that links form exploration and engineering is lacking; a tool that allows exploration of parametric forms quickly with instantaneous engineering and physical feedback to assess feasibility of the concept.
    This paper presents a journey of exploration in developing workflows and associated tools in the digital virtual space that allows collaboration, co-creation between architects and engineers so as to work seamlessly in creating structurally efficient, functional yet architectural pleasing structures.


  • Chun Hin Fong, Jacky, Adabelle Long Wun Poon; Wing Sze Ngan, Chung Hei Ho, Garvin Goepel and Kristof Crolla, “Augmenting Craft with Mixed Reality” in B. Slocum, V. Ago, S. Doyle, A. Marcus, M. Yablonina, and M. del Campo (eds.), ACADIA 2020: Distributed Proximities / Volume I: Technical Papers [Proceedings of the 40th Annual Conference of the Association of Computer Aided Design in Architecture (ACADIA), Online and Global, 24-30 October 2020, pp. 436-444.

    ABSTRACT | This paper discusses novel methods for and advantages from integrating Augmented Reality (AR) and photogrammetry in hand-clay-sculpting workflows. These techniques permit non-trained users to achieve higher precision during the sculpting process by holographically overlaying instructions from digital 3D source geometry on top of the sculpting material. By employing alternative notational systems in design implementation methods, the research positions itself in a Post-Digital context aimed at humanizing digital technologies. Throughout history, devices have been developed to increase production, such as Henry Dexter’s 1842 “Apparatus for Sculptors” for marble sculpting. Extrapolating from this, the workflow presented in this paper uses AR for overlaying extracted infor¬mation from 3D models directly onto the sculptor’s field of vision. This information can then become an AR-driven guidance system that assists the sculptor. Using the Microsoft HoloLens, holographic instructions are introduced in the production sequence, connecting the analogue sculpture fabrication directly with a digital environment, thus augmenting the craftspeople's agency. A series of AR-aided sculpting methods were developed and tested in a demonstrator case study project that created a small-scale clay copy of Henry Moore’s “Sheep Piece” (1971-2). This paper demonstrates how user-friendly soft- and hardware tools have lowered the threshold for end-users to develop new methods that straightfor¬wardly facilitate and improve their crafts’ effectiveness and agency. This shows that the fusion of computational design technology and AR visualization technology can innovate a specific craft’s design and production workflow, opening the door for further similar appli¬cation developments in more architecture-specific fabrication contexts.

  • Goepel, Garvin and Kristof Crolla, “Augmented Reality-based Collaboration - ARgan, a bamboo art installation case study”, in D. Holzer, W. Nakapan, A. Globa, I. Koh (eds.), RE: Anthropocene, Design in the Age of Humans - Proceedings of the 25th CAADRIA Conference - Volume 2, Chulalongkorn University, Bangkok, Thailand, 5-6 August 2020, pp. 313-322.

    ABSTRACT | ARgan is a geometrically complex bamboo sculpture that relied on Mixed Reality (MR) for its joint creation by multiple sculptors and used latest Augmented Reality (AR) technology to guide manual fabrication actions. It was built at the Chinese University of Hong Kong in the fall of 2019 by thirty participants of a design-and-build workshop on the integration of AR in construction. As part of its construction workflow, holographic setups were created on multiple devices, including a series of Microsoft HoloLenses and several handheld Smartphones, all linked simultaneously to a single digital base model to interactively guide the manufacturing process. This paper critically evaluates the experience of extending recent AR and MR tool developments towards applications that centre on creative collaborative production. Using ARgan as a demonstrator project, its developed workflow is assessed on its ability to transform a geometrically complex digitally drafted design to its final physically built form, highlighting the necessary strategic integration of variability as an opportunity to relax notions on design precision and exact control. The paper concludes with a plea for digital technology's ability to stimulate dialogue and collaboration in creative production and augment craftsmanship, thus providing greater agency and more diverse design output.

  • Crolla, Kristof and Garvin Goepel, “Designing with Uncertainty: Objectile Vibrancy in the TOROO bamboo pavilion”, in D. Holzer, W. Nakapan, A. Globa, I. Koh (eds.), RE: Anthropocene, Design in the Age of Humans - Proceedings of the 25th CAADRIA Conference - Volume 2, Chulalongkorn University, Bangkok, Thailand, 5-6 August 2020, pp. 507-516.

    ABSTRACT | This paper challenges digital preoccupations with precision and control and questions the status of tolerance, allowance and error in post-digital, human-centred architectural production. It uses the participatory action research design-and-build project TOROO, a light-weight bending-active bamboo shell structure, built in Hsinchu, Taiwan, in June 2019, as a demonstrator project to discuss how protean digital design diagrams, named 'vibrant objectiles,' are capable of productively absorbing serendipity throughout project crystallisation processes, increasing designer agency in challenging construction contexts with high degrees of unpredictability. The demonstrator project is then used to discuss future research directions that were exposed by the project. Finally, the applicability of working with 'vibrant objectiles' is discussed beyond its local project use. Common characteristics and requirements are extracted, highlighting project setup preconditions for which the scope covered by the architect needs to be both broadened and relaxed to allow for feedback from design implementation phases.


  • Wong, Long Hin Nichol and Kristof Crolla, “Simplifying Catenary Wood Structures - Post-Digital Expansion of GluLam’s Construction Solution Space”, ACADIA 19: UBIQUITY AND AUTONOMY, Proceedings of the 39th Annual Conference of the Association for Computer Aided Design in Architecture (ACADIA), ISBN 978-0-578-59179-7, The University of Texas at Austin School of Architecture, Austin, Texas 21-26 October, 2019, pp. 150-155.

    ABSTRACT | This work-in-progress action research paper describes the development of a novel computation-driven design method for low-tech producible, structurally optimized, suspended wooden roofs based on near catenary-shaped glue-laminated beams. The paper positions itself in a post-digital architectural context with as goal to introduce recent technological advances into developing construction contexts characterized by limited production means. The paper starts by evaluating the pre-existing practical, procedural, and economic drivers behind the design and fabrication of curved glue-laminated beams—one of the most ecologically sustainable structural elements commonly available. A method is proposed that employs genetic algorithms to simplify the fabrication of a suspended roof structure’s range of weight-saving, catenary shaped beams. To minimize the number of costly high-strength steel pressure vise setups required for their individual production, idealized curve geometries are minimally tweaked until a single, reusable jig setup becomes possible. When combined with a wooden roof underfloor, tectonic systems that employ such beams have the potential to dramatically reduce structure material requirements while producing architecturally engaging and spatially complex nonstandard space. The method’s validity, applicability, and architectural design opportunity space is tested, evaluated, and discussed through a conceptual architectural design project proposal that operates as demonstrator. The paper concludes by addressing future research directions and architectural advantages that the proposed design and fabrication methodology brings, especially for developing construction contexts with limited access to digital fabrication technology.

  • Fingrut, Adam, Kristof Crolla and Darwin Lau, “Automation Complexity – Brick by Brick.” in M. Haeusler, M. A. Schnabel, T. Fukuda (eds.), Intelligent & Informed - Proceedings of the 24th CAADRIA Conference - Volume 1, Victoria University of Wellington, Wellington, New Zealand, 15-18 April 2019, pp. 93-102.

    ABSTRACT | This paper discusses the design and construction of brick structures with the aid of a Cable Driven Parallel Robot (CDPR) and defines the role of robotic equipment within the context of design and construction complexity. Explored is the impact of computational workflows with the deployment of scalable and dexterous Computer Numerically Controlled (CNC) equipment with standardized components on a construction site. The use of this design and construction setup reduces assembly complexity and creates increased opportunity for execution of design intent. This shift from using a skilled labor force to robotic assembly increases designer ability to control fundamental decisions relating material expressiveness deployment in the field.

  • Chan, Zion and Kristof Crolla, “Simplifying Doubly Curved Concrete: Post-Digital Expansion of Concrete’s Construction Solution Space.” In M. Haeusler, M. A. Schnabel, T. Fukuda (eds.), Intelligent & Informed - Proceedings of the 24th CAADRIA Conference - Volume 1, Victoria University of Wellington, Wellington, New Zealand, 15-18 April 2019, pp. 23-32.

    ABSTRACT | This action research project develops a novel conceptual method for non-standardised concrete construction component fabrication and tests its validity through a speculative design project. The paper questions the practical, procedural and economic drivers behind the design and construction of geometrically complex concrete architecture. It proposes an alternative, simple and economical fabrication method for doubly curved concrete centred on the robotic manufacturing of casting moulds through 5-axis hotwire foam cutting for the making of doubly-curved fiber-reinforced concrete (FRC) panels. These panels are used as light-weight sacrificial formwork for in-situ concrete casting. The methodology's opportunity space is tested, evaluated and discussed through a conceptual architectural design project proposal that operates as demonstrator. The paper concludes by addressing the advantages of a design-and-build architecture delivery setup, the potential from using computational technology to adapt conventional design and construction procedures and the expanded role within the design and construction process this gives to architects.

  • Wang, Sining and Kristof Crolla, “Design practice complexity in the Post-Digital age: theoretical discussion and comparative case study of non-standard building façades.” in M. Haeusler, M. A. Schnabel, T. Fukuda (eds.), Intelligent & Informed - Proceedings of the 24th CAADRIA Conference - Volume 2, Victoria University of Wellington, Wellington, New Zealand, 15-18 April 2019, pp. 481-490.

    ABSTRACT | This paper starts by introducing an expression proposed by William J. Mitchell measuring the "complexity" of a designed and constructed architectural project. After reviewing other interpretations of this term, as well as specific peculiarities from the building industry, the article expands this metric from an organisational and technological perspective. This is followed by the case studies of six non-standard façades whose process complexities are driven by their project-specific affordances. By comparing built projects of different architects and implementation environments, the paper suggests specific criteria for non-standard architectural designs. Application of acquired knowledge has the potential to help architects better control their project's design and construction solution space.

  • Crolla, Kristof & Hodgson, Paula & Ho, Angel. (2019). “‘Peer Critique’ in Debate: A Pedagogical Tool for Teaching Architectural Design Studio”. International Journal for the Scholarship of Teaching and Learning.

    ABSTRACT | Post-digital architectural education aims to empower future architects by developing open-mindedness and technical skills for the design of non-standard spatial configurations. Students can learn through exploration and experimentation, using three-dimensional graphic design software to generate initial designs and quality feedback, with a mixed model of peers and panel judges assessing final projects. Ratings of individual contributions and performance are commonly found in literature on peer assessment, but qualitative comments from peers can also provide good information on strengths and weaknesses. This study shows that peer critique in the form of debate can be an effective pedagogical tool for educators to provide quality feedback to the presenting group. This paper explores how architecture students responded to this method in a design studio for a master’s degree in architecture in a university in Hong Kong. Interviews were audio-recorded, transcribed and subsequently analysed using the coding system of qualitative software NVivo 11. The responses of the students were positive, although they experienced differences in feedback from different stakeholders.


  • Crolla, Kristof. "Building simplexity: the 'more or less' of post-digital architecture practice." Doctor of Philosophy (PhD), Architecture and Urban Design, RMIT University, 2018.

    A strong dichotomy exists between the increased architectural design agency offered by digital tools today and the affordances given by many construction contexts, especially building environments in developing countries with limited available means.

    This creative practice research project questions whether computational design tools can be used differently in contemporary architecture practice so that onsite affordances can be increased in parallel with the expanding virtual design solution space. It postulates that by incorporating incertitude as a productive and constructive component in alternative computation-driven design and materialisation methods (rather than as negatives), the locally available solution space for built architecture can be dramatically expanded and onsite ability and agency increased.

    The study develops a methodology that aims at procedurally managing serious slippage from aleatory occurrences during materialisation and transforming it into a practical opportunity for non-standard project realisation. In doing so the case is made for the use of more democratic epistemic models and more intelligent structures of approximation than (common) deterministic approaches in digital design would allow for.

    The field of study is ‘Post-Digital Architectural Design Practice,’ which is characterised by virtually unlimited computational ability, precision and unprecedented access to specialised and complex processes, wherein the challenge lies in the translation of its expanded agency into professional application. The employed methodologies are ‘Participatory Action Research’ and ‘Reflective Practice,’ applied on an existing and developing body of creative works of increasing scale and complexity, built in volatile construction contexts. Their study identifies and challenges preconceived notions behind their creation and frames these in dialectic space for further development until higher-order knowledge is extracted in contribution to the overall field of study.

    The demonstrator employs protean design diagrams capable of absorbing serendipity throughout the project crystallisation process. Named ‘vibrant objectiles,’ these diagrams consist of holistic, computation-driven, associative design models that are procedural in nature and cover both project design and delivery. They are built from a select number of interdependent components that are optimised for local implementation. These are placed in and communicate across a hierarchy of scale and impact, enabling the emergence of larger-scale complexity. They relate to aspects of project materiality, material system and/or materialisation, and can incorporate site-specific idiosyncrasies. They have potentially high levels of volatility or uncertainty, termed ‘vibrancy’. This vibrancy is managed throughout the project development, rather than locked down. From early on, the extensibility of potential deviations is harnessed within the developing objectile that incorporates continuous feedback from rigorous prototyping. Until project completion, uncertainty is given room to feed back into the system, giving rigour and animus to the whole. Hence, rather than seeing the act of design materialisation as the literal translation of digitally designed objects, the proposed method embraces fluctuations as the design develops into its final singular site-specific solution.

    Evaluation of the potential and efficacy of the proposed method challenges the role practising architects are often given and the extent of their authority within professional legal frameworks. For the proposed method to successfully bridge the dissociation between theory and practice, the architects’ mode of operation needs to change, and the extent of their actions to dramatically expand. However, once these changes are made possible, the discussed projects demonstrate that the increase of local onsite affordance can be substantial.

  • Crolla, Kristof, Cheng, Paul Hung Hon, Chan, Ding Yuen Shan, Chan, Arthur Ngo Foon and Lau, Darwin. “Inflatable Architecture Production with Cable-Driven Robots”. in T. Fukuda, W. Huang, P. Janssen, K. Crolla, S. Alhadidi (eds.), Learning, Adapting and Prototyping - Proceedings of the 23rd CAADRIA Conference - Volume 1, Tsinghua University, Beijing, China, 17-19 May 2018, pp. 9-18

    ABSTRACT | This paper argues for alternative methods for the in-situ integration of robotics in architectural construction. Rather than promoting off-site pre-fabrication through industrial robot applications, it advocates for suspended, light-weight, cable-driven robots that allow flexible and safe onsite implementation. This paper uses the topic of large-scale inflatable architectural realisation as a study case to test the application of such a robot, here with a laser-cutter as end-effecter. This preliminary study covers the design, development, prototyping, and practical testing of an inherently scale-less cable-driven laser-cutter setup. This setup allows for the non-size specific cutting of inflatable structures' components which can be designed with common physics simulation engines. The developed robotic proof of concept forms the basis for several further and future study possibilities that merge the field of architectural design and implementation with mechanical and automation engineering.

  • Fung, Enrica and Crolla, Kristof. “Choreographed Architecture - Body-Spatial Exploration”. in T. Fukuda, W. Huang, P. Janssen, K. Crolla, S. Alhadidi (eds.), Learning, Adapting and Prototyping - Proceedings of the 23rd CAADRIA Conference - Volume 1, Tsinghua University, Beijing, China, 17-19 May 2018, pp. 101-110

    ABSTRACT | This paper presents a design-methodological case study that looks into the practical expansion of conventional conceptual architectural design media by incorporating contemporary technology of motion capture. It discusses challenges of integrating dance movement as a real-time input parameter for architectural design that aims at translating body motion into space. The paper consists of four parts, beginning with a historic background overview of scientists, physiologists, artists, choreographers, and architects who have attempted capturing body motion and turning the motion into space. The second part of the paper discusses the iterative development of the 'Dance Machine' as a methodological tool for the integration of motion capture into conceptual architectural design. Thirdly, the paper discusses tested design applications of the 'Dance Machine' by looking at two sited applications. Finally, the overall methodology is critically assessed and discussed in the light of continuous development of creative applications of motion capturing technology. The paper concludes by highlighting the architectural potential found in specific qualities of dance and by advocating for a broader palette of tools, techniques, and input methods for the conceptual design of architecture.

  • Wang, Sining, and Kristof Crolla. “Architect’s Feasible Design Solution Space - Case studies of non-standard façade design practice in China”. in W. Huang, M. Williams, D. luo, Y. Wu, Y. Lin (eds.), Learning, Adapting and Prototyping – Short Paper Proceedings of the 23rd CAADRIA Conference, Tsinghua University, Beijing, China, 17-19 May 2018, pp. 21-26

  • Wang, Sining, and Kristof Crolla. “Interaction Between Parametric Modelling and Product Development - A pre-rationalisation approach in non-standard architectural practice”. in W. Huang, M. Williams, D. luo, Y. Wu, Y. Lin (eds.), Learning, Adapting and Prototyping – Short Paper Proceedings of the 23rd CAADRIA Conference, Tsinghua University, Beijing, China, 17-19 May 2018, pp. 253-258

    ABSTRACT | This paper questions the ideal digital paradigm of its applicability for non-standard architectural practice in China. Streamlined multi-disciplinary cooperation may constrain when facing a challenging construction context which notorious for its high speed, lack of craftsmanship, low budgets, and poor detailing. Living with this, however, a group of digital practitioners has successfully been able to complete several non-standard architectural projects with a complex form. An argument raises suggesting an essential part of their success lies in their alternative use of typical parametric models, which are adapted to create tolerance space between design, development, and implementation process in response to local challenges. Here, we study two non-standard cases from Chinese architectural practice HHDFUN. By analysing the project delivery processes, this paper ambitious to extract higher-level knowledge that will contribute to the professional practice and facilitate the extension of an expanded, yet purely digital design solution space into the challenging material world of local construction.

  • Crolla, Kristof. “Bending Bamboo Rules: Beyond Century-Old Typologies,” Journal of Architectural Education, 72:1 (2018), 135-145

    ABSTRACT | The ZCB Bamboo Pavilion, built in Hong Kong in 2015, is the largest bending-active bamboo gridshell structure to date. Globally, Hong Kong is one of the last places where raw bamboo is actively used in everyday construction. Yet, despite being ecologically sustainable, bamboo craftsmanship is slowly dissipating. Through several observations, discoveries, and projects, this paper discusses the sequential journey that generated a bold alternative to pre-existing local bamboo building typologies, challenging general perceptions and building regulations. The trade itself is not giving another path, but is receiving it as an alternative to fading away. Hence: by infusing digital technology into the design and construction process of a century-old building method, a fading vernacular tradition offers an alternative course of action centered on computational design.

  • Y. Wu, H. H. Cheng, A. Fingrut, K. Crolla, Y. Yam and D. Lau, "CU-brick cable-driven robot for automated construction of complex brick structures: From simulation to hardware realisation," 2018 IEEE International Conference on Simulation, Modeling, and Programming for Autonomous Robots (SIMPAR), Brisbane, Australia, 2018, pp. 166-173. doi: 10.1109/SIMPAR.2018.8376287

    ABSTRACT | Robotic building construction has had significant advances in the recent decades, but also has various limitations. In particular, construction typically requires a robot to operate within a large space for long hours and be able to transport between sites. Cable-driven parallel robots (CDPRs) show strong potentials within the automation of construction due to its desirable characteristics, such as high payload-to-weight ratio, transportability, scalability and reconfigurability. This paper proposes a simulation-based analysis, design and pre-execution verification for a cable-driven brick structure building system (CU-Brick), among which a way to determine the buildable workspace where the construction could be constructed is proposed. Simulations are used to do the workspace analysis, design of the brick structure within the workspace and also verification that the motions can be executed. Using this simulation approach, real demonstrations have been performed to show that indeed the system is able to construct the brick structures safely and consistently.

  • Crolla, Kristof. “Beyond Architecture: How Computation empowers the 21st Century Master Builder.” In Andrea Yuri Flores Urushima (ed.). 2018, Architectural and Planning Cultures Across Regions – Digital Humanities Collaboration Towards Knowledge Integration, CIRAS Discussion Paper No. 81, Center for Southeast Asian Studies, Kyoto University. 47-53