Led by innovative architect and designer Neri Oxman, MIT’s Mediated Matter lab is responsible for some of the most inventive and avant-garde additive manufacturing research out there. From 3D printed glass technology to its responsive and bioinspired mask collections, Mediated Matter has a complex vision for 3D printing and digital fabrication which it continually brings to the table in compelling ways.
In a recent undertaking, the Mediated Matter team has proposed a Water-based Digital Fabrication Platform which combines “an age-old crustacean-derived material with robotic fabrication and synthetic biology” to produce ecological and biodegradable structures.
The innovative system uses a robotically controlled multi-chamber extrusion mechanism to deposit a biodegradable composite material made from chitosan, a chitin derivative sourced from ground arthropod shells (like shrimp). Chitin, which is being explored for AM applications elsewhere, is the planet’s second most abundant natural polymer.
“Once printed,” explains Mediated Matter on its website. “Constructs are form-found through evaporation patterns given by the geometrical arrangement of structural members, and by the hierarchical distribution of material properties. Controlled wrinkling follows. Each component will find its shape upon contact with air, and biodegrade upon contact with water.”
In other words, the structures 3D printed using the water-based digital fabrication platform can be easily recycled, making the technology suitable for making fully recyclable products (such as packaging goods or bags), temporary installations, architectural components and more.
Notably, the AM process is designed to 3D print the chitin-derived composite material with “functional, mechanical and optical gradients across length scales.” A computational workflow is also integrated for the purpose of enabling multi-material and multi-scale objects.
“The workflow encodes for, and integrates, domain-specific meta-data relating to local, regional and global feature resolution of heterogeneous material organizations,” adds the MIT research group. “Geometrically diverse constructs associating shape-informing variable flow rates and material properties to mesh-free geometric primitives are deposited.”
To ensure that the 3D printed structures don’t necessarily erode when they come into contact with water, the research group has also added a Cyanobacteria coating to chitosan samples which provides surface functionalization as well as water resistance and conductivity properties. Overall, the Water-based Digital Fabrication Platform utilizes natural and renewable substances to create biodegradable structures with graded properties.
“Derived from the ocean, shaped by water and augmented by photosynthetic marine bacteria, these structures represent the transformation of a marine arthropod’s shell into a tree-like chitosan made skin that will ultimately convert sunlight into biofuel,” says Mediated Matter. “The platform and its products demonstrate the Material Ecology approach to shape and property formation by design. It is a realization of the ancient biblical verse ‘from Earth to Earth,’ from water to water.”
The Water-based Digital Fabrication Platform project was led by MIT Media Lab researchers Jorge Duro-Royo, Laia Mogas-Soldevila, Daniel Lizardo and Neri Oxman.