Title
Gain-Sparsity and Symmetry-Forced Rigidity in the Plane.
Abstract
We consider planar bar-and-joint frameworks with discrete point group symmetry in which the joint positions are as generic as possible subject to the symmetry constraint. We provide combinatorial characterizations for symmetry-forced rigidity of such structures with rotation symmetry or dihedral symmetry of order 2k with odd k, unifying and extending previous work on this subject. We also explore the matroidal background of our results and show that the matroids induced by the row independence of the orbit matrices of the symmetric frameworks are isomorphic to gain sparsity matroids defined on the quotient graph of the framework, whose edges are labeled by elements of the corresponding symmetry group. The proofs are based on new Henneberg type inductive constructions of the gain graphs that correspond to the bases of the matroids in question, which can also be seen as symmetry preserving graph operations in the original graph.
Year
DOI
Venue
2016
10.1007/s00454-015-9755-1
Discrete & Computational Geometry
Keywords
Field
DocType
Frame matroids,Frameworks,Group-labeled graphs,Infinitesimal rigidity,Rigidity matroids,Rigidity of graphs,Symmetry
Graph operations,Matroid,Molecular symmetry,Rotational symmetry,Topology,Combinatorics,Symmetry group,Clique-sum,Graphic matroid,Mathematics,Quotient graph
Journal
Volume
Issue
ISSN
55
2
0179-5376
Citations 
PageRank 
References 
1
0.37
14
Authors
3
Name
Order
Citations
PageRank
Tibor Jordán150.91
ViktóRia E. Kaszanitzky293.61
Shin-ichi Tanigawa311118.52