Design and physical validation of a non-planar interlocking element for tubular structures

An interlocking topological structure represents an arrangement of parts designed so that the degrees of freedom of each component are takeover by the surrounding neighbours. For the planar arrangements, there are multiple possibilities to design such assemblies via platonic solids such as tetrahedron, cube, octahedron and osteomorphic geometries. This paper describes the geometrical modelling process of a non-planar interlocking element that can be used to produce tubular structures. The geometric element was defined by two curved surfaces identified with the inner and outer shell of the tubular structure and joined by six curved surfaces, providing through those the interlocking design. The virtual geometry was produced using an additive manufacturing process generating the physical model of a tubular construction assembled from non-planar interlocking elements.