The realization of 3D printing was hotly issued this year because of its unbelievable ability to realize something as you imagine, like science fiction. If you design and input what you want to print, it gives you the product as same as a real one. Furthermore, it is followed by 4D printing, which adds some functions to 3D printing.
4D printing is the technology to print a product that changes its shape and assembles itself reacting to the specific external stimulation like light, temperature, moisture, time, and electromagnetic field. The idea originated with Skylar Tibbits (MIT self-assembly research), and 4D printers use smart material to make products that adjust flexibly to their environment. 4D technology adds the time dimension to the other 3 dimensions. The product can change its shape itself, rather than stay as a “dead object” that is fixed after printing. This amazing ability creates the possibility of recycling the products and self assembly, because the product can adapt its characteristic and shape to diverse conditions several times. 3D printing makes sophisticated products, but they must be assembled by hand. However, unlike 3D printing, 4D printing does not need assembly after printing. Therefore, it can be used to make something in extreme environments like space, where it is difficult to go or to assemble products.
Actually, many scientists are considering applying 4D printing technology to space. Also, 4D printing can be used in bio field. If new bio material is sensitive to body temperature, pH, near infrared ray, and other stimulation, it can function similarly to 4D printing to release drugs according to biorhythm.
In fact, 4D printing is studied the most optimistically in the USA, where the world-leading 3D printing enterprise, Stratasys, is researching 4D printing using new smart materials with MIT self assembly research. The USA Army research institute grants 855,000 dollars for developing 4D printing new smart material to Harvard University and Illinois State University. The USA is especially interested in applying the technology to the military. For instance, it can change the shape or color of army equipment to intensify camouflage and increase the safety of soldiers when they are exposed to toxic gas or sharp materials. Also, it can change the structure of a car to prevent it from corrosion from humidity or salt.
Professor Dong-Woo Cho (ME) said the commercialization of 4D printing will result in huge changes in every field. For example, application to water pipes could control water flow without any pump or valve, application to sports wears could create clothing and equipment that adjust according to sweat emission and loss of body temperature, and application to tires could create tires that re-conform based on road conditions. Image how amazing it will be if a stick changes to a picnic table or the outside art work spontaneously spreads in the morning and shrinks at night.