Architecture professor draws inspiration from biology
Carnegie Mellon is known for its five-year architecture program, yet many students do not realize how interdisciplinary the field can be. It is more than the design and construction of buildings — it is the creative combination of art and science. Architects do not just sketch drawings and make building plans — they collaborate with scientists from all different disciplines and develop innovative materials and building technologies to continuously improve the world of architecture.
Dale Clifford, assistant professor of architecture at Carnegie Mellon, uniquely combines biology and architecture. “I look at natural systems and transfer that knowledge into building technology. Specifically what we’ve been looking at is self-regulating systems and mechanisms — how does an organism tune itself to the world around it? Can buildings do this too?”
Clifford’s unique way of revolutionizing architecture is the reason why Google has asked him to be the materials innovation consultant for a new building that the company is designing. Never before has Google designed its own building. “Google wants to know how to use new and emerging materials in their building practice. We’ll look at a range of materials and my team and I will make models, take photographs, do experiments and then come back and present it to Google to see how they can incorporate it into their building,” Clifford explained. This process is riskier than the normal practice of picking materials that already exist — they are actually developing new products never used before in buildings.
Pointing at an image of a soaring eagle, Clifford said, “This bird is continuously changing its form in response to fluctuating conditions.... This is what buildings should do.”
One material that Clifford has been developing, called a “phase-change” material, is going to be used in the Frick Park Environmental Center in Pittsburgh and is also a possible material for the Google project. As it undergoes a change in phase, in this case from liquid to solid, the material absorbs a large amount of latent heat.
“There’s a company that’s making an organic phase-change material based from palm oil. This type of material is generally behind walls, but we are taking it out of its opaque plastic packaging and developing a new packaging that will allow it to be more visible,” Clifford said. The palm oil material is given a target set-point temperature so that, as the temperature around the building changes, the phase-change material changes from clear to frosty.
Most buildings have set points of temperature which determine when the air conditioning or heating system switches on and off; with walls made of phase change material, the set point would become wider and the air conditioning or heating unit would come on less, making the building more energy efficient. Clifford proposed to have tiles of this sort of material within a glass wall, attached to the glass by gecko feet fiber produced by mechanical engineering professor Metin Sitti.
Two other proposed projects that allow a building to interact with the environment are optic-fiber stalks and petals actuated by shape-memory alloys. The stalk system would look like bundles of fiber-optic tubes with photovoltaic collectors at the tips. Sunlight would be filtered through the tubes to light the interior of the building.
The petal system would be a series of flower-like structures covering a glass wall, seen in the picture below. The petals are connected to a nickel-titanium alloy, which contracts at a target temperature. The contracting of the alloy pulls the petals down so that on a cold day, the petals would be closed to let sunlight in, while on a hot day, the petals would expand to shade the building.
According to Clifford, technologies that allow a building to respond to its environment accomplish two important goals: energy conservation and education. Innovations such as porous walls, phase-change materials, optic-fiber stalks, and petal systems not only improve the mechanics of a building, but provide a visual representation of how the building interacts with its surroundings. “By bringing what is usually inside walls to the exterior of buildings, people would directly be able to understand how we are lowering reliance on mechanical conditioning,” Clifford said.
Innovative building technologies such as those being developed by Clifford’s team require the collaboration of scientists from all different fields. Although students in the Mellon College of Science or Carnegie Institute of Technology might think they have nothing to with the School of Architecture, Clifford said it would be “a feast” if he could work with more scientists and engineers from other fields.
“Architecture always has an expanding footprint,” Clifford said. “In the future I think we’ll be collaborating more with materials scientists, physicists, chemical engineers, to develop new materials for buildings that are more responsive. It’s happening — it’s not the mainstream, but it’s an undercurrent.”