Tracking Consensus For Multi-agent Systems Research Articles

Tracking Consensus of Multi-Agent Systems With Varying Number of Agents Under Actuator Attacks

Tracking Consensus of Multi-Agent Systems With Varying Number of Agents Under Actuator Attacks

Fixed-time consensus of second-order multi-agent systems with nonlinear dynamics

The authors mainly discuss finite-time tracking consensus and fixed-time tracking consensus of multi-agent systems for second-order with inherent nonlinear function and disturbance under a directed interaction graph in this work. By sliding mode control theory, consensus tracking controllers are proposed to ensure that sliding mode can be reached and maintain on it in finite time and fixed time. By using some theoretical knowledge of control, such as graph theory and Lyapunov theory, we make the system to reach consensus in finite time and fixed time by choosing the right parameters. In addition, the calculation leads to the conclusion that settling time of finite-time consensus is associated to initial state, while settling time of fixed-time consensus is interrelated to parameters but not to the initial state. The feasibility of the theory is proved by simulation experiments.

Tracking Control of Multi-Agent Systems Using a Networked Predictive PID Tracking Scheme

With the rapid development of network technology and control technology, a networked multi-agent control system is a key direction of modern industrial control systems, such as industrial Internet systems. This paper studies the tracking control problem of networked multi-agent systems with communication constraints, where each agent has no information on the dynamics of other agents except their outputs. A networked predictive proportional integral derivative (PPID) tracking scheme is proposed to achieve the desired tracking performance, compensate actively for communication delays, and simplify implementation in a distributed manner. This scheme combines the past, present and predictive information of neighbour agents to form a tracking error signal for each agent, and applies the proportional, integral, and derivative of the agent tracking error signal to control each individual agent. The criteria of the stability and output tracking consensus of multi-agent systems with the networked PPID tracking scheme are derived through detailed analysis on the closed-loop systems. The effectiveness of the networked PPID tracking scheme is illustrated via an example.

Observer-Based Output Feedback Tracking Consensus for Multi-Agent Systems With Periodic Intermittent Communication and Input Saturation

Observer-Based Output Feedback Tracking Consensus for Multi-Agent Systems With Periodic Intermittent Communication and Input Saturation

Robust bipartite tracking consensus of multi-agent systems via neural network combined with extended high-gain observer

In this paper, the robust bipartite tracking consensus problem for second-order multi-agent systems has been addressed in the presence of lumped disturbances and unknown velocity information. The leader’s dynamics are modeled by uncertain fractional-order equality based on the neural network (NN), and the followers can only obtain the position information of the leader under the signed networks. A novel robust bipartite tracking consensus control scheme is developed by combining the NN approximators, the continuous sliding mode control (SMC) strategy, and the improved extended high-gain observer (EHGO). The improved EHGO is used to compensate for and estimate each agent’s lumped disturbances and unknown velocity information in the controller design process. Moreover, NN is constructed to approximate the velocity and acceleration of the uncertain leader’s dynamics for generating the feedforward signal of controllers, and the adaptive update laws of estimation parameters are generated online based on the Lyapunov function. Finally, the effectiveness of the proposed control strategy is verified by some numerical simulations.

Adaptive event-triggered distributed model predictive control for tracking consensus of multiagent systems

<p indent="0mm">The tracking consensus of multiagent systems based on distributed model predictive control (DMPC) is a current research hotspot. However, as a research difficulty, effective solutions to deal with external disturbances and reduce computational resource consumption are lacking. This paper proposes a new constraint tightening scheme and establishes a new distributed optimization problem. Moreover, an adaptive event-triggering mechanism is designed using the idea of variable prediction horizon, and an adaptive event-triggered DMPC approach for the tracking consensus of multiagent systems is proposed, effectively solving the problems of the unsatisfaction of constraints and computational resource consumption in the tracking consensus of multiagent systems. The effectiveness of the proposed approach is validated by a multivehicle system simulation.

Tracking Consensus of Multi-Agent Systems Under Switching Topologies via Novel SMC: An Event-Triggered Approach

This paper investigates the tracking consensus issue for second order multi-agent systems (MAS) under switching topologies by using a novel event-triggered sliding mode control strategy. First, in order to compensate for the effect brought by the information transmission caused by event-triggered sampling and the switching topologies respectively, the dynamic sliding mode control (SMC) mechanism is proposed based on two discrete level sets. By considering the event-triggered rules and the sliding mode method jointly, the corresponding limited-information-based protocol is constructed. This technology does not require the system dynamics to reach the sliding mode manifold compared to previous studies. In addition, with the help of the boundary layer technique, the control protocol is designed to be continuous, which can reduce the chattering of the system and increase the life of machine. Through strict mathematical derivation, when the dwell time of switching between different communication graph candidates is within a limited range, it is proved that the consensus error of the nonlinear multi-agent systems (NMAS) with disturbances converges to an adjustable bounded set, and the networked harmonic oscillator systems (NHOS) without disturbances asymptotically reaches zero. Finally, Zeno behavior can be avoided entirely, and several numerical examples are presented to evaluate the efficiency of the proposed algorithms.

Seeking Tracking Consensus for General Linear Multiagent Systems With Fixed and Switching Signed Networks.

The existing studies for tracking consensus of multiagent systems (MASs) are all restricted to networks with only cooperative relationships among agents. Tracking consensus, however, requires beyond these traditional models due to the ubiquitous competition in many real-world MASs, such as biological systems and social systems. Taking into account this fact, this article aims to extend the dynamics of tracking consensus to signed networks containing both cooperative and competitive relationships among agents. A group of agents with general linear dynamics is considered. The cases of the fixed network as well as switching networks are analyzed, respectively. In the end, some algebraic conditions related to the network structure and the positive/negative edge weight are established to ensure the implementation of tracking consensus. Moreover, the single decoupling system is allowed to be strictly unstable in theory, and the upper bound of the eigenvalue modulus of the system matrix related to the system instability is given.

Event-Based Tracking Consensus for Multiagent Systems With Volatile Control Gain.

This work investigates the tracking consensus problem of multiagent systems over directed networks, where the control gains follow certain volatile patterns. Some event-based consensus protocols are formulated so as to reduce the redundant execution of control. By using an extended differential inequality with a time-dependent coefficient, criteria for tracking consensus under time- and state-dependent triggering conditions are constructed, respectively. It is proved that the time average of the control gain, together with the agent dynamics, network topology, and triggering conditions, governs the consensus despite the fluctuation of control gain. The derived theorem can be utilized to ensure consensus with intermittent strategies aiming to lessen the burden in communications, including aperiodic on-off control with periodic perturbation and pulse-modulated on-off control. Unlike existing works, the requirement of a positive lower bound of control ratios is removed and, thus, a wide range of control gain patterns is possible, signifying higher flexibility in intermittent policy design. Finally, numerical examples are provided to further illustrate the theoretical results.

Distributed Fast Finite-Time Tracking Consensus of Multi-Agent Systems With a Dynamic Leader

Distributed fast finite-time tracking consensus (FTTC) is investigated for first-order nonlinear multi-agent systems (MASs), where the leader has an external input unknown to all followers. Based on global finite-time stability and Lyapunov stability, two distributed tracking protocols are proposed to guarantee fast FTTC. First, a basic distributed non-smooth protocol for solving this problem is proposed and analyzed. A limitation of the designed protocol is that the control gains should depend on some global information like the spectrum of Laplacian matrix. To remove this limitation, a fully distributed protocol is further designed and analyzed. Theoretical studies imply that the states of the considered MASs will also achieve fast FTTC. Finally, two simulation examples are performed on Chua’s circuit system to verify the theoretical results.

Bipartite asynchronous impulsive tracking consensus for multi-agent systems

Bipartite asynchronous impulsive tracking consensus for multi-agent systems

Sampled-data-based event-triggered secure bipartite tracking consensus of linear multi-agent systems under DoS attacks

This paper investigates secure bipartite consensus tracking of linear multi-agent systems under denial-of-service(DoS) attacks by using event-triggered control mechanism with data sampling. Both bipartite leader-following and containment tracking consensus are considered in this paper. The event-triggered control protocol using sampled-data information is designed to save limited resources. The communication channels are interrupted by intermittent DoS attacks. Sufficient conditions on the sampling periods, attack frequency and attack duration are obtained to ensure secure bipartite tracking consensus of the multi-agent systems. Finally, simulation example is provided to illustrate the effectiveness of the theoretical results.

Fixed-Time Connectivity Preserving Tracking Consensus of Multiagent Systems with Disturbances

This text studies the fixed-time tracking consensus for nonlinear multiagent systems with disturbances. To make the fixed-time tracking consensus, the distributed control protocol based on the integral sliding mode control is proposed; meanwhile, the adjacent followers can be maintained in a limited sensing range. By using the nonsmooth analysis method, sufficient conditions for the fixed-time consensus together with the upper and lower bounds of convergence time are obtained. An example is given to illustrate the potential correctness of the main results.

Distributed bipartite tracking consensus of nonlinear multi-agent systems with quantized communication

This paper mainly tends to address distributed bipartite tracking consensus problem for nonlinear multi-agent systems subject to logarithmic quantization. Based on appropriate quantized criterion, a distributed protocol with static coupling gain is developed. By employing Lyapunov technique and other mathematical analysis, the results show that distributed bipartite tracking consensus of multi-agent systems can be ensured with quantized relative state measurements, if some conditions are met. Additionally, compared with distributed protocol, the fully distributed protocol with dynamic coupling gain is further designed and analyzed via adaptive control, which is independent of any global information. Finally, simulations are exploited to support our theoretical analysis.

Bipartite tracking consensus for multi-agent systems with Lipschitz-Type nonlinear dynamics

This study concentrates on the bipartite tracking consensus for Lipschitz-Type multi-agent systems (MASs) in the presence of a single leader. Distributed neighbor-based bipartite tracking consensus algorithms with leader’s control inputs are developed for both the nonzero and zero cases, under which the bipartite tracking consensus is reached. In contrast to the existing works on this topic, the Lipschitz nonlinear agent dynamics are taken into consideration. Additionally, the control inputs of the leader can be nonzero. Numerical simulations are performed to examine the potentials of results.