New Results in Cooperative Adaptive Optimal Output Regulation

This paper investigates the cooperative adaptive optimal output regulation problem of continuous-time linear multi-agent systems.As the multi-agent system dynamics are uncertain,solving regulator equations and the corresponding algebraic Riccati equations is challenging,especially for high-order systems.In this paper,a novel method is proposed to approximate the solution of regulator equations,i.e.,gradient descent method.It is worth noting that this method obtains gradients through online data rather than model information.A data-driven distributed adaptive suboptimal controller is developed by adaptive dynamic programming,so that each follower can achieve asymptotic tracking and disturbance rejection.Finally,the effectiveness of the proposed control method is validated by simulations.

Cooperative Output Regulation of Heterogeneous Systems over Directed Graphs:A Dynamic Adaptive Event-Triggered Strategy

This paper investigates the cooperative output regulation problem of heterogeneous linear multi-agent systems over directed graphs with the constraint of communication bandwidth.Given that there exists an exosystem whose state information is not available to all agents,the authors develop distributed adaptive event-triggered observers for the followers based on relative information between neighboring agents.It should be pointed out that,two kinds of time-varying gains are introduced to avoid relying on any global information associated with the network,and dynamic triggering conditions are designed to get rid of continuous communications.On the basis of the designed observers,the authors devise a local controller for each agent.Compared with the existing related works,the main contribution of the current paper is that the cooperative output regulation problem for general directed graphs is solved requiring neither global information nor continuous communications.

An overview on the distributed internal model approach and its applications

The cooperative output regulation problem has been studied by two approaches:the distributed observer(DO)approach and the distributed internal model(DIM)approach,respectively.Each of these two approaches has its own merits and weaknesses.Recently,we presented an overview on the cooperative output regulation problem by the DO approach.This paper further surveys the cooperative output regulation problem by the DIM approach.We first summarize the constructions and the roles of two different versions of the internal models:the distributed p-copy internal model and the distributed canonical internal model.Then,we describe an integrated framework that combines the DO approach and the DIM approach.Extensions and variants of the DIM and their applications will also be highlighted.

Output Regulation of Multiple Heterogeneous Switched Linear Systems

This paper addresses the cooperative output regulation problem of a class of multi-agent systems （MASs）. Each agent is a switched linear system. We propose an agent-dependent multiple Lyapunov function （MLF） approach to design the switching law for each switched agent. The distributed controller for each agent is constructed based on a dynamic compensator. A sufficient condition for the solvability of the output regulation problem of switched agent networks is presented by distributed controllers and agent-dependent multiple Lyapunov function approach. Finally, simulation results demonstrate the effectiveness of our theory.

BIK1 cooperates with BAK1 to regulate constitutive immunity and cell death in Arabidopsiss

Summary In Arabidopsis, both the membrane-anchored receptor-like kinase （RLK） BAK1 and the receptor-like cytoplasmic kinase （RLCK） BIK1 are important mediators of transmembrane signal transduction that regulate plant development and immunity. However, little attention has been paid to their genetic association. This study found the bak1 bik1 double mutant of Arabidopsis displayed a severe dwarfism phenotype due to constitutive immunity and cell death in developing plants. These data suggest that BIK1 cooperates with BAK1 to regulate constitutive immunity and cell death.