Ultralight fractal structures from hollow tubes

The transition from solid to hollow beams changes the scaling of stability versus loading analogously to increasing the hierarchical order by one.

Physical Review Letters 109, 204301 (2012)

D. Rayneau-Kirkhope, Y. Mao, R. Farr

Ultralight fractal structures from hollow tubes

A fractal design is shown to be highly efficient both as a load bearing structure and as a general metamaterial. Through changing the hierarchical order of the structure, the scaling of material required for stability against loading can be manipulated. We show that the transition from solid to hollow beams changes the scaling in a manner analogous to increasing the hierarchical order by one. An example second order solid beam frame is constructed using rapid prototyping techniques. The optimal hierarchical order of the structure is found for different values of loading. Possible fabrication methods and applications are then discussed.

More in Fractal structures

  • Mechanics Research Communications

    Hierarchical space frames

    A systematic way to vary the power-law scaling relations between loading parameters and volume of material aids the hierarchical design process.

  • Physical Review E

    Structural imperfections

    Fractal structures need very little mass to support a load; but for current designs, this makes them vulnerable to manufacturing errors.

  • Physical Review E

    Hierarchical structures

    The most efficient load-bearing fractals are designed as big structures under gentle loads ... a situation common in aerospace applications.