If you haven't already done so, make sure to check out this months issue (April 2013) of Architectural Design (AD) titled Computation Works: The Building of Algorithmic Thought.  Edited by Xavier De Kestelier and Brady Peters, this issue focuses on emerging themes in computational design practices, showcasing built and soon-to-be-built projects and provides a state of the art look at current computational design techniques.

In addition to some amazing articles written by Daniel DavisDavid RuttenDaniel PikerGiulio Piacentino, Arthur van der Harten, Thomas Grabner and Ursula Frick, and many more... it also features an article that I co-authored with Jason K. Johnson titled Firefly: Interactive Prototypes for Architectural Design.  

In addition, make sure you also take a look at the book Prototype!  edited by Julian Adenauer and Jorg Petruschat which was published by Form+Zweck last summer (2012).  Written by leading individuals at world renown design labs and research centers, this book offers a unique compilation of articles centered around the topic of advanced forms of prototyping.  In my article, IDE vs. IPE: Toward and Interactive Prototyping Environment I discuss the need to shift toward a more visually oriented Interactive Prototyping Environment (IPE) which addresses the limitations found in the existing IDE paradigm and opens up creative new opportunties for artists and designers.


I am excited to be teaching a one-day Interactive Surfaces workshop for the upcoming Facades+ Conference being held in New York City on April 11th-12th.  The event has an amazing line up of speakers and workshops which are being taught by some of the industries leaders including: Robert Aish (Autodesk), Nathan Miller (Case), Gil Akos & Ronnie Parsons (Studio Mode), Neil Meredith (Gehry Tech), and  John Sargent (SOM).

The Interactive Surfaces workshop will concentrate on producing facade prototypes that are configurable, sensate, and active.  The facade of a building is the liminal surface across which information and environmental performance is frequently negotiated.  Given dynamic context of our built environment; the facade must be capable of intelligent adaptation over time.

In this workshop, we'll be focusing on new hardware and software prototyping techniques; primarily focusing on a wide range of sensing and actuation modalities in order to build novel interactive devices. Using remote sensors, microcontrollers (Arduino), and actuators, we will build virtual and physical prototypes that can communicate with humans and the world around them.  Using both Grasshopper and the Firefly plug-in, you will learn how to create intelligent control strategies for interactive or responsive facades.

Click here to sign up!

The participants who sign up for this workshop will also be the first to get their hands on the new Firefly Interactive Prototyping Shield which I have been developing. This shield provides access to a number of built-in, ready-to-use sensors and actuators including: 3 linear sliders (potentiometers), a light sensor, a two-axis joystick, 3 push buttons, a red LED, a yellow LED, a Green LED, and a Tri-color LED, 2 servo connections, and a high-voltage MOSFET circuit capable of driving lights, valves, DC motors, etc.  Each participant will not only walk away with a kick ass new hardware kit, but valuable knowledge in how to create new types of interactive prototypes!




Most digital design involves surface modeling.  Even so called “solid” modeling software is based on representations where a “solid” is that which is enclosed by a set of boundaries (known as boundary representations or ‘Brep’ for short). While digital representations of solid objects are often treated as homogeneous and discrete entities, the reality is somewhat different.  In the real world, material distributions are continuous and varied.  Yet, with regard to architectural components, the variability of material within a volume is usually concealed (ie. porosity of bricks, various types of reinforcements for concrete structures, etc.) and is rarely taken into account during the early design process.  With the advent of 3d printing techniques, a new possibility emerges - allowing us the ability to reconsider the aesthetic and mechanical properties of visible reinforcement.  In this post we discuss a structural optimization method in conjunction with the possibility of treating structural elements as living in a material continuum that renders objects and reinforcements fuzzy.

Topology optimization is a form finding technique which seeks to optimize a certain material distribution with given boundary conditions (ie. types of supports and loads). It departs from standard form finding techniques in that it assumes that a volume of virtual material can continuously vary its stiffness or density throughout space.  Until now the final step of this process involved a cut off threshold; a sharp boundary of hard solid material and void. However intermediate steps of topology optimization suggest grey zones of intermediate material stiffness.  These results were usually discarded as unrealistic from a fabrication point of view. With multi material printing we can experiment and speculate about possible realizations of such fuzzy structural objects.  The analysis and design of the experiments presented here were carried out using the tools Topostruct (a standalone application) and Millipede (a plugin for Grasshopper) created by Panagiotis Michalatos and Sawako Kaijima. 

Three experiments were conducted: the first is the design of a chair using standard topology optimization techniques and interpretation (single solid material), the second was a new type of truss/beam element with fuzzy visible reinforcement (soft transparent material encasing gradations of a harder bone-like structure), and the last one was a similar interpretation to the cantilevering slab which produces patterns reminiscent of a leaf (since leaves solve the same structural problem).

Example 1: A chair

The chair example uses topology optimization to gradually remove material from a solid volume on which the actions of a person seating are applied (ie. vertical and horizontal loads for the seating position). 3d printing allows us the ability to materialize the intricate structures that emerge especially around moment connections.

Figure 1: from left to right: Initial boundary volume setup for chair configuration and successive steps of material redistribution through topology optimization. Darker areas designate denser material.

Figure 2: Features of the chair become more refined during each subsequent step through the topology optimization process.

Figure 3 & 4: Converged geometry of the topology optimization process.

Example 2: A fuzzy truss

For the second experiment we revisited one of the simplest forms from engineering textbooks. The truss like structures that act like bridges supporting a distributed load at their two end points. However, in this example, the topology optimization routine was set up in such a way that instead of a solid object, it yielded a continuous variation of material stiffness. Using Objet’s multi-material printing technology, we were able to develop a gradated structure using a transparent rubbery material and a hard white material (and the gradations in between the two) to achieve an outcome that looks, feels, and structurally acts like a fuzzy reinforced structure. 

Figure 5: [top left]: Setup of boundary conditions for simple bridge [main volume + supports at the two lower corners and distributed load at the top]. [top right]: Deflected shape of solid material after load application. [bottom images]: stress distribution and topology optimization contours. Inner contours represent regions where stronger material is required.

Figure 6: Topology optimization drives material redistribution within the volume of the truss. A fuzzy truss shaped beam reinforcement gradually emerges.

Figure 7: A 3d printed diagram showing the distributed load on top and the two supports on either end plus the optimal shape of the reinforced region.

Figure 8: Using multi-material printing technology, a fuzzy bone-like structure can be created using gradients between a transparent rubbery material and an opaque hard material. In this way the actual outcome of the topology optimization process can be directly materialized.

Example 3: A leaf-slab

Our final experiment involved the reinterpretation of a different traditional system - the cantilevering slab. The distributed load over this horizontal plate puts similar requirement to that of a leaf and topology optimization yields branching structures reminiscent of the venation found in leaves.

Figure 9: A fuzzy branching pattern emerges when a distributed load is applied to a cantilevering slab from a single support, resembling the vein patterns of  leaves.

Figure 10: A 3d printed diagram showing the cantilevered load and support structure.

Figure 11: Multi-material printing allows us to materialize semi-rigid and semi-transparent fuzzy structural systems as a kind of gradual reinforcement embedded in the material where the boundaries between softer and harder parts are blurred.

The ability to continuously vary the stiffness and transparency of material will allow us to rethink design techniques and technologies, software tools, and analysis methods beyond the surface modeling paradigm. In the scale of product design this is already possible thanks to technologies like multi-material 3d printing. Such experiments will be valuable precedents when speculating about new types of continuous and fuzzy building systems.

This research was generously supported by Objet Technologies.  For more information about their 3d printing technology, visit