When a porcupine feels threatened, its quills bristle. In humans, the same anatomical reflex is responsible for goose bumps. Neither response is voluntary, and both typically occur in response to external stimuli. But the porcupine's reaction is considerably more dramatic, its prominent spines undulating as the skin to which the rigid quills attach moves, pliably, atop muscle and bone.

Caress of the Gaze, a 3-D printed garment created by architect and designer Behnaz Farahi, was inspired by the involuntary action of animal skin, but also by its complex architecture—the interplay of muscles, hair, feathers, quills, scales. "The skin is not a homogenous surface," she explains. "A fish's scales are hard, but underneath them there is a soft structure, a flexible mesh of sorts that that allows the scales to bend and flex."

This complexity is clearly visible in Farahi's project, which she developed in San Francisco as an artist in residence at Autodesk's Pier 9 workshop. Like a fish's scales, Caress of the Gaze contains rigid structures and pliant ones. It's difficult to incorporate both in a 3-D printed object, but Farahi says she overcame this problem by printing along a gradient, with materials of varying flexibility and density. Like the skin of an animal, the garment moves, not atop muscles, but an actuation system assembled from shape-memory alloy. And, like goose bumps, the garment responds autonomously, controlled by a front-mounted camera that detects the orientation of an onlooker's gaze. "It's modeled after actual skin," says Farahi "not just morphologically, but behaviorally. It's the response to external stimuli that makes it come alive."

Farahi, who has a background in architecture and is pursuing a PhD in interactive media at USC, says she's fascinated by technologies and materials that can expand the functionality of our bodies, and that it's up to designers—fashion designers, especially—to help define how we use these advances to interact with our environment. "Caress of the Gaze is obviously speculative," she says. A shawl equipped with computer vision? It seems so out-there. But then, in a not-so-crazy way, garments seem a perfectly logical place to implement technology. "Clothing is one of the most significant interfaces between our bodies and our environments," says Farahi. "It defines so much of who we are."