Inkjet printers create light powered hinges
Imagine if you could take an everyday inkjet printer, and use it to create dynamic self-assembling three dimensional structures. Researchers at North Carolina State University have been doing exactly this, and the results have a simple elegance that is really quite mesmerising to behold.
Dr Michael Dickey, one of the authors of the paper “Self-folding of polymer sheets using local light absorption” explains the team’s findings:
This is a novel application of existing materials, and has potential for rapid, high-volume manufacturing processes or packaging applications.
It all happens remarkably quickly. A pre-stressed plastic sheet is run through a standard inkjet printer, where bold black lines are printed onto the material. When exposed to an infrared light source (such as a heat lamp) the darker areas absorb more energy and folds occur without any external mechanical intervention.
Click through for a video to see just how fast this shape-changing occurs.
The wider the printed line, the greater the angle of fold. So with a bit of careful thinking beforehand, some nifty outcomes are possible. Cutting the material into different patterns and then printing varying thicknesses on each side of the plastic can enable complexity of forms far beyond a simple cube or pyramid. This behaviour has been modelled by Dr Dickey and his colleagues to achieve precise control over both the amount of movement and the speed of transformation.