‘Cable' and 'strut’ for a panel-hinge framework
This talk will be a discussion on how to systematically develop the rigidity of a panel-hinge tensegrity framework. While it is possible to model such a framework by imposing constraints on in-plane rigidity using bars and out-of-plane rigidity through coplanar conditions, we aim to explore alternatives that do not rely on the conventional bar-joint framework. We made a few initial attempts using the signed dihedral angles as coordinates, where the constraints are in the form of 'the multiplication of a series of rotational matrices equals to Identity'. Some initial questions include how to 1) define 'cable', 'struct', 'tension' and 'compression' from this form of constraint; 2) interpret the stress and strain and make them consistent with continuum mechanics (or shell theory) 3) examine the theory with physical model. We anticipate that the findings can be directly generalized to the rigidity of hypergraph tensegrity structures, and will have a good resonance with graphic statics.