With each swipe of the 3-D printer, more of the car emerges. At first, there are only four thin lines on the bottom of the airtight, clear plastic box. But each time the printer head passes, vapor jets out of it and mixes with a fine powder to make a solid stratum. The lines grow fatter and taller until they’re tires. A few hundred passes later, Larry Sass, SM ‘94, PhD ‘00, opens the printer’s cover and pulls out a plaster model of a four-door car that’s just slightly bigger than a matchbox.
The car is a quick example of the printer’s ability to turn a computer-aided-design (CAD) drawing into a tangible scale model. The technology is not new; it’s been used for more than a decade by manufacturers of everything from automobiles to hearing aids. But Sass sees a bigger application for it–much bigger. He wants to use it to revolutionize how buildings are constructed.
Sass, an assistant professor of architecture, is a specialist in a process that has come to be known as rapid prototyping. The idea is to translate computer designs into three-dimensional, fully formed or easily assembled scale models using any one of a half-dozen machines like those that cram his lab. Alongside the 3-D printer are another machine that precisely directs streams of liquid plastic and a set of computer-directed cutters that can shape paper, metal, plastic, and wood into pieces that have only to be fit together to form a miniature skyscraper or dollhouse-sized furniture.
A CAD design, no matter how intricately detailed, is still only a conceptual model. Machines like Sass’s faithfully incarnate the ideas of designers as models that can yield aesthetic and structural insights or reveal flaws, helping the designers perfect their products. Rapid prototyping bypasses the abstractness of blueprints and allows hands-on experience of a design as a whole.
Many product manufacturers today use this method to refine CAD designs that will, in turn, direct an almost entirely automated construction process. From cars to computer chips, human hands are involved in manufacturing only during design, inspection, and assembly. Sass’s vision is to bring this type of automation to architecture. At first, he believes, rapid prototyping will be implemented only in classrooms and drafting studios as a learning and design tool. But in the future the technology could enable safe and rapid mechanized building construction.
The architectural traditionalists who still dominate the field, however, have resisted this change. With their rulers, pencils, and blueprints, they are wary of departures from the minimalist practices honed since the Middle Ages. “The people that really control architecture today have an old-school mentality,” Sass says. “They’re not familiar with a lot of planning tools that are available to them, so they tend to stick to what they’re familiar with.”
During his first three years on the faculty, Sass pieced together his lab in a department that at first seemed reluctant to lend space to such a new type of study. Through grants, he raised nearly $250,000 for machines. With each device, he received a little more square footage of space. The lab in Building 7 has now been active for a year.