## Characterizing 1-Dof Henneberg-I graphs with efficient configuration spaces (810)

Citations: | 1 - 1 self |

### BibTeX

@MISC{Gao810characterizing1-dof,

author = {Heping Gao and Meera Sitharam},

title = {Characterizing 1-Dof Henneberg-I graphs with efficient configuration spaces},

year = {810}

}

### OpenURL

### Abstract

We define and study exact, efficient representations of realization spaces of a natural class of underconstrained 2D Euclidean Distance Constraint Systems(EDCS, Linkages, Frameworks) based on 1-degree-of-freedom(dof) Henneberg-I graphs. Each representation corresponds to a choice of parameters and yields a different parametrized configuration space. Our notion of efficiency is based on the algebraic complexities of sampling the configuration space and of obtaining a realization from the sample (parametrized) configuration. Significantly, we give purely combinatorial characterizations that capture (i) the class of graphs that have efficient configuration spaces and (ii) the possible choices of representation parameters that yield efficient configuration spaces for a given graph. Our results automatically yield an efficient algorithm for sampling realizations, without missing extreme or boundary realizations. In addition, our results formally show that our definition of efficient configuration space is robust and that our characterizations are tight. We choose the class of 1-dof Henneberg-I graphs in order to take the next step in a systematic and graded program of combinatorial characterizations of efficient configuration spaces. In particular, the results presented here are the first characterizations that go beyond graphs that have connected and convex configuration spaces.

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Citation Context ...c complexity for example convexity; however, for this manuscript, these factors are subsumed in the sampling complexity since configuration space of this manuscript is a 1-parameter space. In [8] and =-=[17]-=- a series of exact combinatorial characterizations are given for connected, convex and complete configuration spaces of low sampling and realization complexity for general 2D and 3D EDCSs (including d... |

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Characterizing 1-Dof Tree-Decomposable graphs with efficient configuration space,” in preparation
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Citation Context ... clusters and v1, v2 and v3 are shared vertices. A generalization of the results presented here from Henneberg-1 graphs to the larger class of Tree- or Triangle-decomposable graphs appears in [8] and =-=[18]-=-. A Simple 1-dof Henneberg-I graph G is obtained by removing a base edge f from a Henneberg-I graph (note that there can be more than 1 possible base edge for a given Henneberg-I graph, refer to Figur... |