Skip to main content

Lund University Publications

LUND UNIVERSITY LIBRARIES

Scalability and Fragility in Bounded-Degree Consensus Networks

Tegling, Emma LU ; Middleton, Richard H. and Seron, Maria M. (2019) 8th IFAC Workshop on Distributed Estimation and Control in Networked Systems, NECSYS 2019 In IFAC-PapersOnLine 52. p.85-90
Abstract

We investigate the performance of linear consensus algorithms subject to a scaling of the underlying network size. Specifically, we model networked systems with nth order integrator dynamics over families of undirected, weighted graphs with bounded nodal degrees. In such networks, the algebraic connectivity affects convergence rates, sensitivity, and, for high-order consensus [n ≥ 3), stability properties. This connectivity scales unfavorably in network size, except in expander families, where consensus performs well regardless of network size. We show, however, that consensus over expander families is fragile to a grounding of the network (resulting in leader-follower consensus). We show that grounding may deteriorate system... (More)

We investigate the performance of linear consensus algorithms subject to a scaling of the underlying network size. Specifically, we model networked systems with nth order integrator dynamics over families of undirected, weighted graphs with bounded nodal degrees. In such networks, the algebraic connectivity affects convergence rates, sensitivity, and, for high-order consensus [n ≥ 3), stability properties. This connectivity scales unfavorably in network size, except in expander families, where consensus performs well regardless of network size. We show, however, that consensus over expander families is fragile to a grounding of the network (resulting in leader-follower consensus). We show that grounding may deteriorate system performance by orders of magnitude in large networks, or cause instability in high-order consensus. Our results, which we illustrate through simulations, also point to a fundamental limitation to the scalability of consensus networks with leaders, which does not apply to leaderless networks.

(Less)
Please use this url to cite or link to this publication:
author
; and
publishing date
type
Chapter in Book/Report/Conference proceeding
publication status
published
subject
keywords
Distributed control, Large-scale systems, Robustness
host publication
8th IFAC Workshop on Distributed Estimation and Control in Networked Systems
series title
IFAC-PapersOnLine
volume
52
edition
20
pages
6 pages
conference name
8th IFAC Workshop on Distributed Estimation and Control in Networked Systems, NECSYS 2019
conference location
Chicago, United States
conference dates
2019-09-16 - 2019-09-17
external identifiers
  • scopus:85082692930
ISSN
2405-8963
DOI
10.1016/j.ifacol.2019.12.131
project
Fundamental mechanisms for scalable control of large networks
language
English
LU publication?
no
additional info
Publisher Copyright: © 2019 IFAC-PapersOnLine. All rights reseved.
id
1266b0f3-987a-48ed-a921-7779e3ac6915
date added to LUP
2021-11-24 09:49:04
date last changed
2023-01-24 21:11:42
@inproceedings{1266b0f3-987a-48ed-a921-7779e3ac6915,
  abstract     = {{<p>We investigate the performance of linear consensus algorithms subject to a scaling of the underlying network size. Specifically, we model networked systems with n<sup>th</sup> order integrator dynamics over families of undirected, weighted graphs with bounded nodal degrees. In such networks, the algebraic connectivity affects convergence rates, sensitivity, and, for high-order consensus [n ≥ 3), stability properties. This connectivity scales unfavorably in network size, except in expander families, where consensus performs well regardless of network size. We show, however, that consensus over expander families is fragile to a grounding of the network (resulting in leader-follower consensus). We show that grounding may deteriorate system performance by orders of magnitude in large networks, or cause instability in high-order consensus. Our results, which we illustrate through simulations, also point to a fundamental limitation to the scalability of consensus networks with leaders, which does not apply to leaderless networks.</p>}},
  author       = {{Tegling, Emma and Middleton, Richard H. and Seron, Maria M.}},
  booktitle    = {{8th IFAC Workshop on Distributed Estimation and Control in Networked Systems}},
  issn         = {{2405-8963}},
  keywords     = {{Distributed control; Large-scale systems; Robustness}},
  language     = {{eng}},
  pages        = {{85--90}},
  series       = {{IFAC-PapersOnLine}},
  title        = {{Scalability and Fragility in Bounded-Degree Consensus Networks}},
  url          = {{http://dx.doi.org/10.1016/j.ifacol.2019.12.131}},
  doi          = {{10.1016/j.ifacol.2019.12.131}},
  volume       = {{52}},
  year         = {{2019}},
}