Not content with the future-altering feats of fabricating body organs in a lab and spanners in space, another dimension is being added to the revolution in manufacturing. Led by Professor Marc in het Panhuis, scientists from the ARC Centre of Excellence for Electromaterials Science have discovered that 3D printed dynamic materials can morph into new structures when exposed to changes in temperature, pressure, magnetic field, vibrations, light and water. This is 4D printing – with the fourth dimension being their shapeshifting over time. Reactive materials evolve, fold and self-assemble like a Transformer toy that would make Optimus Prime proud.
The first to use this technology in this way, the team have 4D printed a smart valve made from mechanically robust hydrogel ‘ink’ that reacts to heat, autonomously opening and closing when hot water hits it. This discovery that self-dissembling materials can be 3D printed, become 4D active when you need them and then disappear could alter the future of design forever – from being able to control the temperature of buildings, to advancing tissue engineering, bionics, water treatment, security and drug delivery.
Panhuis is now working on short-term medical functioning devices called ‘Edible Electronics’, soft hydrogel pills which eject batteries when dissolved in the body. “When coupled with sensors, batteries monitor electrical activity of soft tissue in the gastrointestinal tract. Combined with edible electrodes the soft pill dissolves to reveal the battery which becomes activated and autonomously carries electrical stimulation of tissues for digestion disorders,” he says. “As the materials are edible the body will process them naturally without leaving a trace or causing any side effects. This is known as transient behavior.” Evolving from the 4D printed valve, it’s not a tough pill to swallow.
Professor Marc in het Panhuis, ARC Centre of Excellence for Electromaterials Science (ACES), University of Wollongong