In a world where flexibility and adaptability are the watchwords of transformation, 4D printing is the kind of technology that could offer new solutions. This additive manufacturing technique produces objects with "behavior," adaptable enough to evolve with time (this famous fourth dimension), and which could notably help respond to environmental issues.
While the immense creative potential of 3D printing has yet to be fully explored, some researchers are already talking about 4D printing to shape the future. Skylar Tibbits, coordinator of the Self-Assembly Lab at Massachusetts Institute of Technology (MIT) is one of the early pioneers in the field, reveals Peri, a formwork manufacturing and distribution company on the architecture blog Archdaily.
4D printing makes it possible to print material that can be modified, transformed or moved thanks to its properties. As a result, the 4D-printed object will be able to adapt to its environment over time. This could prove a boon in a fast-changing world, while also helping to meet the challenges of mobility, infrastructure, health and the environment.
Conrad Mastalerz, a PhD student in materials science at France's Université de Reims Champagne-Ardenne, explains the concrete utility of 4D printing in an article on The Conversation. Following a research project on prostheses to alleviate a problem of natural bone regeneration, he explains that 4D printing will allow this 3D-printed prosthesis to evolve and change shape.
"In other words, a 4D-printed object in the shape of a bud could open into a flower under the action of an external stimulus," he writes in the article. "This work would make it possible to obtain a prosthesis at a lower cost and in a short period of time with properties similar to bones, and that with time would disappear without leaving any trace so that only the bone remains," the researcher concludes.
Challenges to overcome
Yet, this design process involves several challenges when it comes to creating these transformable objects.
"Such operations require work to correctly combine material, processes, and functionalities. As well as develop methodology based on the triad of design-modelling-simulation so that the printed object responds in an appropriate way to external stimuli," writes Giancarlo Rizza, a CEA researcher specialized in 4D additive manufacturing, in Polytechnique Insights. The difficulty lies in designing an object with "behavior" that can respond to external stimuli in the desired way. There is still a long way to go before this technology becomes widespread.
Another aspect noted by the specialist Giancarlo Rizza, is that the novelty of this technology implies finding profitable production and economic models to help it move beyond scientific circles.
