The objects comprise a rigid polymer that makes up most of the structure and an elastic polymer for the moving parts. The researchers print all parts in a single step with a multi-material 3D printer.
Professor Shea explains: “Printing a flat initial form with rigid and elastic sections in a single step is highly efficient. It would be much more complex and time consuming to produce the three-dimensional object and assemble it from separate components.”
Similar approaches have been used in aerospace for some time, for example, to transport structures into space in a very small envelope.
As well as aerospace applications, the scientists are also considering the simple construction of ventilation systems, systems for opening and closing valves or medical applications, such as stents.
Currently, these structures are reconfigured by hand, but work is being made on a drive that will extend the structures in reaction to temperature.
The researchers say it may also be possible to control the structures using pneumatic tubing or swelling materials that change shape depending on humidity.
While 3D printers have become a standard fixture in many design offices – researchers are already looking to add another dimension to the process: time. The hope is that 3D printed objects will be able to morph and change shapes, or even internal structures, over time by either external induced forces, temperature changes, or other changes to ambient conditions.