Nexorade
Nexorade
Read here about nexorades, a type of structure that, due to its interwoven nature, shares many features with tensegrity structures.
Overview
Nexorades are a new name for an old class of interwoven space structures also known as a multi-reciprocal grid. Such reciprocal frame structures are clearly sisters to tensegrity structures. Rinus Roelofs was a leading researcher in these structures, tracing them back to a drawing in Leonardo Da Vinci's notebooks.
Each of the elements of a nexorade is referred to as a nexor. A nexor looks very much like a tensegrity cells--that notion of a strut that has its tendon firmly attached, like the Tensegritoy struts. The term nexor is a Latin for link, so nexorade implies an assembly of nexors. Each nexor has four connection points, two at the ends of the nexor and two at two intermediate points along the nexor's body. The nexors are interwoven and the system can be erected quickly using simple connectors.
Connecting nexors yields an entire family of lattice space structures that can be quickly assembled and deployed. The hyper-tensegrity Georgia Dome by Mathys Levy and Weidlinger Associates 1992 is based on such a structure.
TaffGoch's nexorade work
TaffGoch, a leading SketchUp artist, has posted some nexorades along with many Geodesic dome renderings. See
http://taffgoch.deviantart.com/
http://browse.deviantart.com/?qh=§ion=&global=1&q=nexorade
http://forums.sketchucation.com/viewtopic.php?f=81&t=31501
Bavarel's nexorade work
Olivier Baverel and Hoshyar Nooshin are two researchers publishing work on nexorades. Nexorades require sophisticated CAD tools and algorithms as their geometry is rather difficult to work out. Baverel, at the Surrey Centre for Engineering Structures and Materials, proposes a genetic method for working out nexorades, similar to that used for regularisation of member lengths of a lattice space structure. This method for the shape finding of nexorades is now available through a standard function in the programming language Formian. See http://www3.surrey.ac.uk/eng/research/ems/ssrc/projects.htm. In another publication, Baverel proposes a "fictitious mechanical behaviour" to solve the form-finding problem. He writes, "The dynamic relaxation algorithm is used with a model that takes into account the eccentricity between the elements. Its implementation is explained and its versatility is illustrated through several examples covering various fields of applications going from form-finding problems to non-linear structural analysis of structures." In this article he compares the structural behaviour of nexorades is compared with more conventional triangulated structures.
Links and references
For a good overview of tensile structures that includes truss systems, tensegrity and nexorades, see Sebestyen, Gyula. 2003. New Architecture and Technology. An excerpt is hosted here: http://arch-tour.blogspot.com/2009/04/space-structures.html. It can be downloaded here, http://www.scribd.com/doc/28761510/New-Architecture-and-Technology
Article by Baverel in Nexus Journal, readable in Google Books online, http://books.google.com/booksid=pMvG5_H5wDUC&pg=PA280&lpg=PA280&dq=nexorade&source=bl&ots=LXe71bCTXd&sig=NkZd7sIZOOD4dJbwrOM-re3PElc&hl=en&ei=L_evTLavM8fNswbW7NTZDQ&sa=X&oi=book_result&ct=result&resnum=8&ved=0CDUQ6AEwBw#v=onepage&q=nexorade&f=false