|Image from Wellcome Images, CC BY 4.0 (http://creativecommons.org/licenses/by/4.0)], via Wikimedia Commons|
We have come a long ways since the old days of printing! Right now 3-D printing is becoming very popular. 3-D printers are not a staple item in all schools, but the 2015 Horizon Report predicts that makerspaces, that include 3-D printers, will become more widespread in the next two to three years. These makerspaces provide students with places where they can put theory into practice and apply the knowledge they have gained in class, like creating prototypes of objects they have designed for class. 3-D printers can also be used by instructors to print models needed for demonstrations in class, such as a heart model that can be taken apart by students and reassembled without damage. 3-D printers are even in space now, where astronauts can use them to create objects, like a wrench (the file for the wrench printed in space is available here, if you want to print your own space wrench!)
Now, with time still left before 3-D printers are common place at universities, 4-D printers are being used! According to a press release on EurekAlert!, these printers work by using materials that can be triggered to change shape after printing when they come into contact with a stimulus, such as water or heat. Researchers at the ARC Center of Excellence for Electromaterials Science created a valve that closes when it comes into contact with hot water.
This is not the first time 4-D printing has been used however. Stratasys, MIT's Self-Assembly Lab, and Autodesk have been working with 4-D printing too. Stratasys' website discusses research on transforming 1-D, 2-D, and 3-D printed items, made from multiple materials, into other 3-D configurations. You could have a 1-D or 2-D item printed in one location that can be moved to another location, say space, before it takes on its 3-D configuration. Even the folding of proteins can be studied using 4-D printing by printing a 1-D strand that will self-fold. You can view the video of a self-folding protein prototype on MIT's Self-Assembly Lab website, along with some other 4-D printed items taking shape. Skylar Tibbits, who created the Self-Assembly Lab, gave a TED talk in 2013 where he said, "this is like robotics without wires or motors." That makes 4-D printed items more durable for outdoor use.
What other possibilities await us with 4-D printing? Could we make working hearts for medical students to use? Could we have structures on buildings that change shape when they reach a certain temperature, such as self-opening awnings? What about water conservation? Could we use 4-D printers to create items that trigger crop irrigation only when water is absent? Certainly a material that can change shape or trigger an event based on temperature or water presence will be useful for studies related to climate change. How would you use 4-D printed items?