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Resilient Leader-Follower Consensus to Arbitrary Reference Values in Time-Varying Graphs

T0 review · 0 major / 3 minor · reviewed 2026-05-25 · grok-4.3

Pith's one-line read Agents in time-varying graphs can resiliently track arbitrary reference states from leaders despite adversarial agents.

desk verdict The paper extends resilient consensus to let normal agents track arbitrary leader references outside the convex hull in time-varying graphs despite bounded adversaries. read the letter →

arxiv 1906.09096 v1 pith:MVWXV7CA submitted 2019-06-19 eess.SY cs.SY

classification eess.SYcs.SY
keywords resilientconsensusleader-followertime-varyinggraphsadversarialagentsmulti-agentsystemsdiscrete-timedynamicsreferencetracking
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

The paper presents methods for multi-agent systems with discrete-time dynamics operating over time-varying graphs to achieve resilient leader-follower consensus. Normal agents track a reference state set by leaders, even when some leaders and followers are adversarial, as long as their number is bounded. This extends previous resilient consensus algorithms that only guarantee values inside the convex hull of initial normal states. A reader would care because it enables reliable tracking of external commands in networks that may have faults or attacks and changing connections.

What carries the argument

Resilient update rules for discrete-time leader-follower consensus in time-varying graphs that filter adversarial influences while tracking external references.

What would settle it

A simulation or experiment where the number of adversaries exceeds the bound and normal agents fail to track the reference state.

Watch

Extended reading notes

Core claim

There exist resilient update rules allowing normally behaving agents to track the reference state propagated by leaders in time-varying graphs, even when a bounded subset of leaders and followers are adversarial, provided the graphs satisfy sufficient connectivity over bounded time intervals.

Load-bearing premise

The communication graphs must be sufficiently connected over bounded time intervals and the number of adversarial agents must stay below the tolerance of the update rules.

Editorial extensions

If this is right

  • Normal agents achieve consensus to reference values outside the convex hull of their initial states.
  • The approach works for time-varying graphs under periodic connectivity conditions.
  • Adversarial behavior is tolerated as long as it is below a known bound.
  • Simulations confirm the tracking performance under the stated conditions.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • These rules could be tested in physical robot teams with wireless communication that changes over time.
  • If the adversary bound is violated, tracking may diverge from the reference.
  • Extensions might include handling delays or continuous-time dynamics.
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Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit.

Referee Report

0 major / 3 minor

Summary. The manuscript proposes methods for resilient leader-follower consensus in time-varying directed graphs under discrete-time dynamics. Normal agents track an arbitrary reference state propagated by a set of leaders, despite a bounded number F of adversarial agents among both leaders and followers, by applying filtering-based update rules (variants of W-MSR) under (r+1)-robustness conditions on the union of the graphs over bounded time intervals.

Significance. If the stated guarantees hold, the work usefully extends resilient consensus results (which confine the value to the convex hull of initial normal states) to a leader-follower tracking setting with arbitrary references. This is relevant for applications such as formation control or state tracking in adversarial multi-agent networks. The reliance on standard robustness assumptions and the inclusion of simulation validation are positive features.

minor comments (3)
  1. [Abstract] Abstract: the phrase 'bounded subset of the leaders and followers behaving adversarially' should explicitly relate the bound F to the robustness parameter r of the graph condition (e.g., r > F) to make the prerequisite assumptions immediately clear to readers.
  2. [Introduction] The manuscript would benefit from a brief comparison paragraph in the introduction or related-work section that distinguishes the new leader-follower tracking result from prior resilient consensus papers that only achieve convex-hull consensus.
  3. [Simulations] Simulation section: the figures should include explicit labels for the time-varying graph sequence, the value of F, and the robustness parameter used, so that readers can directly map the plots to the stated theorem assumptions.

Simulated Author's Rebuttal

0 responses · 0 unresolved

We thank the referee for the positive assessment of our work on resilient leader-follower consensus in time-varying graphs and for recommending minor revision. No specific major comments were provided in the report.

Circularity Check

0 steps flagged · score 0.0 of 10

No significant circularity; derivation is self-contained

full rationale

The paper extends standard resilient consensus methods (variants of W-MSR) to a leader-follower setting for tracking arbitrary references in time-varying graphs. The central claims rest on explicit, externally stated assumptions about (r+1)-robustness of graph unions over bounded intervals and a known adversary bound F, which are prerequisites rather than outputs. No self-definitional steps, fitted inputs renamed as predictions, or load-bearing self-citations that reduce the result to its own inputs appear in the abstract or framing. The derivation chain is independent of the target result and relies on prior literature as external support.

Assumptions & free parameters 0 free parameters · 0 assumptions · 0 invented entities

Abstract provides no explicit free parameters, axioms, or invented entities; assessment limited to the high-level description of bounded adversaries and time-varying graphs.

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Cite this review

Pith. "Pith review of Resilient Leader-Follower Consensus to Arbitrary Reference Values in Time-Varying Graphs." pith.science (2026). https://pith.science/paper/MVWXV7CA

@misc{pith2026190609096,
  author       = {Pith},
  title        = {Pith review of: Resilient Leader-Follower Consensus to Arbitrary Reference Values in Time-Varying Graphs},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/MVWXV7CA}},
  note         = {Machine review of arXiv:1906.09096}
}
read the original abstract

Several algorithms in prior literature have been proposed which guarantee consensus of normally behaving agents in a network that may contain adversarially behaving agents. These algorithms guarantee that the consensus value lies within the convex hull of initial normal agents' states, with the exact consensus value possibly being unknown. In leader-follower consensus problems however, the objective is for normally behaving agents to track a reference state that may take on values outside of this convex hull. In this paper we present methods for agents in time-varying graphs with discrete-time dynamics to resiliently track a reference state propagated by a set of leaders despite a bounded subset of the leaders and followers behaving adversarially. Our results are demonstrated through simulations.

Figures

Figures reproduced from arXiv: 1906.09096 by the authors.

Figure 1
Figure 1. Time-varying graphs used in the last two simulations. In each graph [PITH_FULL_IMAGE:figures/full_fig_p007_1.png] view at source ↗
Figure 3
Figure 3. Leader-follower simulation using the SW-MSR algorithm with a [PITH_FULL_IMAGE:figures/full_fig_p007_3.png] view at source ↗

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Reference graph

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Reviewed May 25, 2026 · model on record in the stance chip above.