Bi-stable foldable tubes
Cylinders are among the most commonly used structures in engineering, e. g., long antennas in space, telescopic masts, storage tanks and drink bottles. In all these applications it is desirable for the structures to be capable of folding away.
Using origami techniques and geometrical analysis we have successfully developed a few concepts
allowing thin-walled cylinders to be shortened to a small package by introducing folding patterns on their surfaces.
It has been found through detailed geometrical analysis that the packaging of such cylinders involves strain variation
within the folds. For certain folding patterns, the strain peak appears during the deployment though the structure
remains strain free when it is fully packaged or open. The structures are therefore bi-stable.
This particular feature makes the expanded cylinders self-locked once they are open. The concept is ideal for deployable booms for aerospace applications.
In comparison with other existing designs, our concept is mechanically simple, almost material independent and cost effective.
The same concepts can be applied for domestic applications as foldable stools and lamp shades.