Disruption via Grounding and Countermeasures in Discrete-Time Consensus Networks⁎This work was supported by the Australian Research Council through grant DP190102859. Issue 2 (2020)

• Record Type: Journal Article
• Authors: Yan, Yamin; Stüdli, Sonja; Seron, Maria M.; Middleton, Richard H.
• Is Part Of: IFAC-PapersOnLine. Volume 53:Issue 2(2020)
• Page Start: 2944
• Page End: 2950
• Publication Date: 2020
• Subjects: Grounding -- discrete-time systems -- scalability -- consensusability -- consensus performance; Automatic control -- Periodicals; 629.805
• DOI: 10.1016/j.ifacol.2020.12.970
• Languages: English
• ISSNs: 2405-8963

Abstract

Abstract: We investigate the disruption of discrete-time consensus problems via grounding. Loosely speaking, grounding a network occurs if the state of one agent no longer responds to inputs from other agents and/or changes its dynamics. Then, the agent becomes a leader or a so-called stubborn agent. The disruption of the agent can be caused by internal faults, safety protocols or externally due to a malicious attack. In this paper we investigate how the grounding affects the eigenratio of expander graph families that usually exhibit good scaling properties with increasing network size. It is shown that the algebraic connectivity and eigenratio of the network decrease due to the grounding causing the performance and scalability of the network to deteriorate, even to the point of losing consensusability. We then present countermeasures to such disruptions in both passive and active manners. Our findings are supported by numerical simulations given within the paper.