Programming material so that it can be triggered to re-shape itself structurally after being 3D-printed is the promise held by the approach known as ‘4D printing’. This technique could completely transform the industrial manufacturing value chain.
Traditional industrial manufacturing has always been a two- or three-stage process. In the first stage raw materials are used to make intermediate products. In the second stage, these parts or components are assembled, and the end products are then installed at their final emplacement. Much has been talked and written about how 3D printing is changing the way raw materials are used to produce individual parts. Now ‘4D printing’ is focusing on the second stage in the production process, i.e. the assembly and final installation of products. The idea is that in the long term each item should be able to self-assemble, using ‘programmable materials’, which would do away with the need for factory assembly lines and lengthy installation procedures and also make installation in what engineers call ‘extreme environments’ a lot easier. In this way, robotics, which were central to many productivity gains in the 20th century, are now incorporated into the actual product material, shortening the value chain between industrial manufacture and the end-consumer all the time.
Printing and programming raw materials
Skylar Tibbits is the young founder of the "Self Assembly Lab" at the Massachusetts Institute of Technology (MIT) in the United States, the world’s top research laboratory for programmable materials. Having qualified as an architect, he then trained in design computation and computer science, having realised that it was possible to programme auto-generative structures into materials. Tibbits first uses the now fairly widespread process of additive layer manufacturing (ALM) – aka 3D printing – which allows him to print out pre-programmed materials. The printed materials are programmed upstream to re-shape themselves later on when they come into contact with a pre-determined element. At the moment the initial Self-Assembly prototypes are programmed to alter shape when they are plunged into a tank filled with water, e.g. plastic molecules of a simple PVC strand that are programmed to bend and form a cube. This is robotics without the wires and motors. The material interacts with its environment in automated fashion.
‘Programmable’ material is the point where the modern ‘Maker’ movement meets large-scale robotics in heavy industry. ‘Maker’ aficionados love to use 3D printing to free themselves from the constraints of industrial manufacture, in the same way that robotics has already totally transformed the secondary sector. The MIT ‘Self-Assembly Lab’ is already working in partnership with specialised consulting and engineering firm GEOSyntec, which works on environmentally-oriented construction projects. The two parties are collaborating to develop water pipes made of programmable material designed to act like peristaltic structures capable of pushing water through the pipework on their own. Going forward, 4D printing could prove extremely useful for installations in extreme environments, from outer space to underwater sites. Materials sent into space could be programmed to transform without any on-the-spot human intervention. Moreover, with ‘4D printing’ technology, the boundaries between hardware and software are becoming increasingly porous. The hardware/ software distinction is likely to become ever more obsolete as physical matter can increasingly be controlled by lines of code.