Water-Based Digital Fabrication
Programmable water-based biocomposites
Research team (Aguahoja I): Jorge Duro-Royo, Laia Mogas-Soldevilla, Daniel Lizardo, Joshua VanZak, Yen-Ju (Tim) Tai, Andrea Ling, Christoph Bader, Nic Hogan, Barrak Darweesh, Sunanda Sharma, James C. Weaver. Undergraduate Researchers: Matthew Bradford, Loewen Cavill, Emily Ryeom, Aury Hay, Yi Gong, Brian Huang, Joseph Faraguna. Prof. Neri Oxman
Research team (Aguahoja II): Nic Lee, Joshua Van Zak, Ramon Elias Weber, Joseph Henry Kennedy, Jorge Duro-Royo, Christoph Bader, João Costa, Sunanda Sharma, James Weaver. Prof. Neri Oxman
Year: 2013-present
Projects: Aguahoja

Percent of Earth's surface covered in water
Position
In the natural world multi-functional forms are achieved through a hierarchy of structural features. A tree, for example, is composed of cells-forming leaves, limb-forming branches, and branch-forming crowns. In design, such complex levels of structural hierarchy and material composition are challenging to emulate. In human-made designs, structural hierarchy and material composition are traditionally achieved by combining discrete homogeneous parts into functional assemblies whereby volumes or surfaces are the determining factor in achieving functionality. Further, conventional computer-aided design tools typically contain geometric and topologic data of virtual constructs but lack robust means to integrate material composition properties within virtual models.
How can we transcend the culture of mono-material assemblies and enable a seamless workflow for the design and direct digital manufacturing of multi-property structures across scales? We answer that question through examining one of design’s most pressing issues: can we utilize water-, rather than petroleum-based materials for the generation of architectural scale structures made almost entirely from biocompatible matter? And, if we can, what would a world without waste look like?
Chitin’s Age (Millions of Years)




Process
A robotically controlled arm and multi-chamber extrusion system are designed to mix, process and deposit biodegradable-composite objects combining natural hydrogels, such as chitosan and sodium alginate, with other organic aggregates. Architectural-scale composite structures digitally fabricated by this platform embody graded properties and feature sizes ranging from micro- to macro scale.
Completed structures may be chemically stabilized or dissolved in water, programmed for time-based recycling within minutes, hours, weeks, months or years. Applications include the fabrication of fully recyclable products or temporary architectural components such as tent structures with graded mechanical and optical properties. Proposed applications demonstrate environmental capabilities such as water-storing structures, hydration-induced shape formation, and product disintegration over time.





In Aguahoja I we focused on the development of a robotic platform for 3D printing biomaterials. We showed that shape and material composition can be directly informed by physical properties (e.g., stiffness and opacity), environmental conditions (e.g., load, temperature, and relative humidity), and fabrication constraints (e.g., degrees-of-freedom, arm speed, and nozzle pressure), etc. Each structure in the collection contains a unique combination of organic materials whose allocation, texture and distribution within the final object are computationally driven and additively manufactured in high resolution. This enables control over specific physical properties and environmental adaptation to changing weather conditions.
In contrast to most synthetic materials, structures included in this collection will react to their environment over their lifespan, adapting their geometry, mechanical behavior and color in response to fluctuations in heat, humidity, and sunlight. Such time-based ‘temporal’ behavior is utilized as a design feature able to sense, inform the user of, and adapt to changing environmental conditions. The robotic fabrication platform is engineered to convert converts cellulose, chitosan, pectin, and other abundant biopolymers, into high-performance sustainable ‘pastes’ that can be 3D printed into objects for applications spanning scales from millimeters to meters.








Policy
Additive manufacturing of regenerated biomaterials is in its infancy despite the urgent need for alternatives to fuel-based products and in spite of the exceptional mechanical properties, availability, and biodegradability associated with water-based natural polymers. Water-based robotic fabrication is an enabling technology for additive manufacturing of biodegradable hydrogel composites.
Digital manufacturing platforms are often critiqued for consuming high levels of energy, producing single-use parts, being wasteful and generating toxic by-products in the process. Water-based production processes, in contrast, consume relatively low amounts of energy, generate multi-functional structures, produce little to no waste, and utilize local non-toxic materials.
The water-based robotic fabrication technology considers water a building block for the construction of architectural scale structures and parts, modeled after Nature’s methods. The platform enables 3D printing of water-based composites and regenerated biomaterials such as chitosan, cellulose or sodium alginate for the construction of highly sustainable products and building components. It demonstrates that water-based fabrication of biological materials can be used to tune mechanical, chemical and optical properties of aqueous material composites.

Publications
Water-based Robotic Fabrication (2014)
Designing a Tree: Fabrication Informed Digital Design and Fabrication of Hierarchical Structures (2018)
Credits
Collaborators & Contributors: Shaymus Hudson, Tzu-Chieh Tang, Prof. Tim Lu and the Lu Lab, Research Laboratory of Electronics at MIT, Nitzan Zilberman, MIT Media Lab
Research Collaborators: Joseph Faraguna, Matthew Bradford, Loewen Cavill, Emily Ryeom, Aury Hay, Yi Gong, Brian Huang, Tzu-Chieh Tang, Shaymus Hudson, Prof. Pam Silver, Prof. Tim Lu
Substructure Production: Stratasys Ltd, Stratasys Direct Manufacturing
Music Composition: Jeremy Flower
Video Production: The Mediated Matter Group, Paula Aguilera, Jonathan Williams
Acknowledgements: MIT Media Lab, NOE. LLC, Stratasys Ltd, MIT Research Laboratory of Electronics, Wyss Institute at Harvard, Department of Systems Biology at Harvard, GETTYLAB, Robert Wood Johnson Foundation, Autodesk BUILD Space, TBA-21 Academy, Thyssen-Bornemisza Art Contemporary, Stratasys Direct Manufacturing, National Academy of Sciences, San Francisco Museum of Modern Art, Esquel Group.
Aguahoja I was acquired for the permanent collection at the San Francisco Museum of Modern Art (since 2018)
All images and videos courtesy Neri Oxman and The Mediated Matter Group