4D Printing Transforms Product Design

Abstract

Imagine water pipe that can constrict or expand in response changes in water pressure or flow rate, or undulate move water, eliminating complex pumps or mechanical valves. Or automobile coatings that can change their structure when environment is wet or when they come into contact with road salt. Or military uniforms that change camouflage patterns when soldier moves different environment or harden into protective barrier when poison gas or shrapnel is detected. All of these may be possible with 4D printing, convergence of smart materials and 3D printing technology, which promises change not only how things get made but what they can do. Change over time is fourth dimension in 4D printing: programmable materials developed for 3D printing applications have potential produce adaptive products whose physical properties alter when triggered by particular stimuli or that self-assemble or self-modify over preprogrammed periods of time. Researchers believe this work will stimulate RD Jennifer A. Lewis, from Harvard School of Engineering and Applied Sciences, an expert in 3D printing of functional materials; and Ralph G. Nuzzo, at University of Illinois, synthetic chemist and an expert in stimuli-responsive materials. As Balazs recently told ZMEscience.com, team has big goals: By integrating our abilities print precise, three-dimensional, hierarchically-structured materials; synthesize stimuli-responsive components; and predict temporal behavior of system, we expect build foundation for new field of 4D printing. The scientist credited with coining term 4D printing, Skylar Tibbits, is director of Self-Assembly Lab at MIT's Department of Architecture. The idea for 4D printing started about two years ago, Tibbits said, to essentially print smart materials, be able customize those smart materials in their shape and their properties, be able print them within objects so there wasn't any assembly required make them sense or actuate or have logic. He points DARPA's programmable matter research of nearly decade ago as the big kick start of this whole vision. The difference, he said, is that in early days, people thought in terms of robotics: Almost everyone was doing robotics. Robotics were solution programmable matter, and I think over time all of us have shifted into much softer, more adaptive, more responsive vision of what programmable matter is. This direction, he says, points certain growing maturity in field, but new technologies have also enabled us do what we wanted do and have eliminated need have these super-heavy mechanical electronic robots that we needed before, and it's much more elegant. Tibbits's team is working on self-assembling materials, with self-assembly defined as a process by which disordered parts build an ordered structure through local interaction. Researchers there have identified key ingredients for self-assembly as simple set of responsive building blocks and some environmental factor--heat, light, pressure, magnetism, motion, even sound or moisture--whose change generates changes in material. Tibbits and his team want coopt these natural forces program matter in controllable, dynamic ways. For example, Tibbits describes how self-tuning footwear might adapt changing performance needs. …