arrow
Return

Angular constraints on planar frameworks

delete2026-09-15
delete0
PRE
AI
S
Sean Dewar
G
Grasegger, Georg
A
Anthony Nixon *
R
Rosen, Zvi
S
Sims, William
M
Meera Sitharam
U
Urizar, David
DOI:10.1016/j.dam.2026.03.009delete
deleteOriginal
deleteOriginal request for help
deleteShare
deleteSave
Abstract

Abstract

En 中文
Consider a collection of points in the plane and the sets of slopes or directions of the lines between pairs of points. It is known that the algebraic matroid on the set of direction constraints between the points is equivalent to the algebraic matroid on the set of distances between the points. This is the well-studied generic 2-dimensional rigidity matroid of a graph. This article studies a higher-level construction built on the slope data: an angle constraint system obtained by prescribing relationships between pairs of slopes. The central question we analyze is: when is an angle system rigid, in the sense that every nontrivial motion alters one of the fixed angles? We formulate the problem in matricial terms for certain edge-colored graphs, finding precise necessary conditions for when such edge-colored graphs are rigid, and a combinatorial characterization of generic rigidity for a special case. We also prove the validity of an equivalent formulation of the angle matroid as the algebraic matroid of a field extension. (c) 2026 Published by Elsevier B.V.
Keywords:
Bar-joint framework
Rigidity matrix
Local rigidity
Angle constraints
Colored graph
Algebraic matroid

Journal

D
Discrete Applied Mathematics
IF:
1.1
Papers:
352
Citations:
7.7K

Organization

State University System of Florida cover
State University System of Florida
Scholars:
12.8W
Papers: 10.9W
Citations: 130
L
lancaster university
Scholars:
1.5K
Papers: 957
Citations: 0
U
university of florida
Scholars:
6.4K
Papers: 2.8K
Citations: 1
I
Illinois State University
Scholars:
264
Papers: 161
Citations: 0
F
Florida Atlantic University
Scholars:
3.2K
Papers: 2.5K
Citations: 4.8K
U
university of bristol
Scholars:
4.2K
Papers: 2.0K
Citations: 1
researcher View more organizations
Cited Papers

Cited Papers

Frameworks with Coordinated Edge Motions
err2022-12-01
err0
PREAI
errSchulze,Bernd; Serocold,Hattie; Theran,Louis
errShare
errSave
Algebraic Matroids in Action
err2020-03-15
err0
PREAI
errRosen,Zvi; Sidman,Jessica; Theran,Louis
errShare
errSave
The Number of Realizations of a Laman Graph
err2018-01-01
err0
PREAI
errJose Capco; Matteo Gallet; Georg Grasegger; Christoph Koutschan; Niels Lubbes; Josef Schicho
errShare
errSave
Body-and-cad geometric constraint systems
err2012-10-01
err0
errOAAI
errKirk Haller; Audrey Lee-St.John; Meera Sitharam; Ileana Streinu; Neil White
errShare
errSave
Rigidity and energy
err1982-02-01
err0
PREAI
errRobert Connelly
errShare
errSave
researcher View more