Hasso-Plattner-Institut
Prof. Dr. Patrick Baudisch
 

HingeCore: Laser-Cut Foamcore for Fast Assembly

Muhammad Abdullah, Romeo Sommerfeld, Bjarne Sievers, Leonard Geier, Jonas Noack, Marcus Ding, Christoph Thieme, Laurenz Seidel, Lukas Fritzsche, Erik Langenhan, Oliver Adameck, Moritz Dzingel, Thomas Kern, Martin Taraz, Conrad Lempert, Shohei Katakura, Hany Mohsen Elhassany, Thijs Roumen, and Patrick Baudisch

HingeCore is a novel type of laser-cut 3D structure made from sandwich materials, such as foamcore. The key design element behind HingeCore is what we call a finger hinge, which we produce by laser-cutting foamcore “half-way”. The primary benefit of finger hinges is that they allow for very fast assembly, as they allow models to be assembled by folding and because folded hinges stay put at the intended angle, based on the friction between fingers alone, which eliminates the need for glue or tabs. Finger hinges are also highly robust, with some 5mm foamcore models withstanding 62kg. Hinge­CoreMaker is a stand-alone software tool that automatically converts 3D models to Hinge­Core layouts, as well as an integration into a 3D modeling tool for laser cutting (Kyub). We have used Hinge­CoreMaker to fabricate design objects, including speakers, lamps, and a life-size bust, as well as structural objects, such as functional furniture. Participants assembled HingeCore layouts 2.9x faster than layouts generated using the state-of-the-art for plate-based assembly (Roadkill).

The key design element of HingeCore, the finger hinge, which we produce by (a) laser-cutting foamcore “half-way”. When folded, the fingers on one side slide between the fingers on the opposite side, where they stay put, based on friction. This basic principle allows for very fast assembly, because (b) finger hinges allow models to be assembled by folding across a pre-scored edge, (c) finger hinges stop folding at a pre­defined angle, allowing the resulting model to take shape, even before all plates are in place, and (d) folded hinges eliminate the need for tabs, as they stay put without glue. At the same time, (e) resulting models are very sturdy, as they are constructed from solid plates and because of the finger structure in finger hinges, (f) allowing the result to withstand high loads. Finally, (g) finger hinges produce a clean look as there are no exposed finger joints.

HingeCoreMaker uses three types of cut lines to create layouts. (a) Red lines are the same as in traditional laser cutting—they instruct the laser to cut through all the layers. (b) Magenta lines cut “half-way”, i.e., they are precisely calibrated so as to cut through the top paper layer and the foam layer, while leaving the bottom paper layer intact. The magenta line is instrumental in creating finger joints. (c) Blue lines, finally, score the middle of the hinge, creating a crease to help with folding precise edges.

(a) Users access HingeCoreMaker’s functionality by setting the material of their model to foam­core. (b) The integration allows users to continue to apply Kyub’s standard tools to their model, ensuring that the design process remains the same. (c) Once users are done modeling, HingeCoreMaker automatically creates a 2D “unfolding”, i.e., where to fold and where to cut.

Assembling HingeCore layouts does not require finding parts and requires little physical force. This allowed our 7-year-old test participant to assembly this chair by herself. The clean white HingeCore surfaces afford coloring, while their sturdiness allows for active play.

Publication

Muhammad Abdullah, Romeo Sommerfeld, Bjarne Sievers, Leonard Geier, Jonas Noack, Marcus Ding, Christoph Thieme, Laurenz Seidel, Lukas Fritzsche, Erik Langenhan, Oliver Adameck, Moritz Dzingel, Thomas Kern, Martin Taraz, Conrad Lempert, Shohei Katakura, Hany Mohsen Elhassany, Thijs Roumen, and Patrick Baudisch
HingeCore: Laser-Cut Foamcore for Fast Assembly
in Proceedings of UIST'22  
Paper PDF | Demo video | ACM dl