Formation Control of Wheeled Mobile Robots With Multiple Virtual Leaders Under Communication Failures

To alleviate the threat of communication failures, a formation control system (FCS) with multiple virtual leaders and semi-Markov switching topologies is proposed in this article. A time-varying formation tracking protocol with an error compensation term is introduced to mitigate the effects among the real leader and the virtual leaders. Sufficient and necessary conditions are derived based on the Routh–Hurwitz criterion. Then, a semi-Markov chain with communication delay is presented to characterize the topology switching process in different communication failure scenarios. The FCS is constructed with a varying gain controller, and its tracking performance is analyzed with the Lyapunov–Krasovskii functional. Finally, substantial experiments with Quanser Qbot2 mobile formation demonstrate the effectiveness of position and velocity tracking for FCS.