Innovation in the world of 3D printing is advancing rapidly, but despite being a recent development, there is a new technology that encompasses – and virtually supersedes – the additive manufacturing techniques: 4D printing, the fourth dimension being time. This seed was sown at the Self-assembly Lab, a laboratory at the renowned Massachusetts Institute of Technology (MIT), coordinated by architect, designer and computer scientist Skylar Tibbits who, in April 2013, presented a preview of this innovation at the TED (Technology Entertainment Design) conference.
What is 4D printing
“4D printing” is intended as the printing of intelligent and programmable materials, capable, therefore, of changing shape, properties, or of performing specific actions, such as self assembly at a later time, when exposed to an external stimulus such as heat, vibration, gravity, magnetism or electricity. The basic principle is scalable, therefore the number of potential applications is enormous, from nano and micrometric devices for biomedical implants that compress upon introduction into the human body and once inside regain their shape, to repair an artery for example, right through to engineering bridges and infrastructure.
A strong collaboration
In a unique research collaboration between Stratasys’ Education, R&D departments and MIT’s Self-Assembly Lab, the 4D Printing process is being developed. With Stratasys’ Connex technology, a single print, with multi-material features, can transform from any 1D strand into 3D shape, 2D surface into 3D shape or morph from one 3D shape into another. The Connex multi material technology allows the researchers to program different material properties into each of the various particles of the designed geometry and harnesses the different water-absorbing properties of the materials to activate the self-assembly process. With water as its activation energy, this technique promises new possibilities for embedding programmability and simple decision making into non-electronic based materials.
In order to take advantage of this new technology from idea conception to reality, in collaboration with a collaboration with Autodesk Research was developed a new software, called Cyborg, a design platform spanning applications from the nano-scale to the human-scale. This software allows for simulated self-assembly and programmable materials as well as optimization for design constraints and joint folding. The aim is to tightly couple this new cross-disciplinary and cross-scalar design tool with the real-world material transformation of 4D printing. The tightly coupled software and hardware tools will eliminate the traditional paradigms of 1. simulating then building or 2. building then adjusting the simulation. This coupled workflow will be unprecedented in the simulation adjusting physical performance and materials promoting new simulated possibilities.
…also shape memory
Researchers at the University of Colorado Boulder have successfully added a fourth dimension to their printing technology, opening up exciting possibilities for the creation and use of adaptive, composite materials in manufacturing, packaging and biomedical applications.

A team led by H. Jerry Qi, associate professor of mechanical engineering at CU-Boulder, and his collaborator Martin L. Dunn of the Singapore University of Technology and Design has developed and tested a method for 4D printing. The researchers incorporated “shape memory” polymer fibers into the composite materials used in traditional 3D printing, which results in the production of an object fixed in one shape that can later be changed to take on a new shape.