共查询到20条相似文献，搜索用时 15 毫秒
1.
Magnus Egerstedt 《Asian journal of control》2013,15(4):944-956
This paper presents an approach to controlling agent positions in single‐leader networks to target points while explicitly taking agent homogeneity into account. When the capabilities of agents to accomplish tasks at each of the targets are identical, then the label of the target points may be permuted while still expressing the same intention. In single‐leader networks which are not completely controllable, such a permutation of the target points may at times move a target closer to the system's reachable subspace, thereby allowing the network to surpass the limitations on controllability when homogeneity is not considered explicitly. To fully exploit this property in homogeneous networks, it is then necessary to find the permutation of a target point which brings it closest to the reachable subspace. However, finding this optimal permutation is shown to be in general a non‐deterministic polynomial‐time (NP)‐hard problem. Specific network topologies are identified for when finding such an optimal permutation of a target point can be advantageous when controlling single‐leader networks. Moreover, an alternate view of the problem of finding optimal permutations is presented in which clustering‐based algorithms can be applied to find suboptimal solutions. 相似文献
2.
In this paper, the controllability of multi‐agent systems is studied under leader‐follower framework, where the interconnection between agents is directed. The concept of leader‐follower connectedness is first introduced for directed graph to check controllability, and some graph‐theoretic conditions are derived for constructively designed topologies. Then, distance partition and almost equitable partition are employed to quantitatively study the controllable subspaces. Moreover, the relationship between the state invariance of multi‐agent systems and the existence of almost equitable partition is discussed. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
3.
This paper considers the gain‐scheduled leader‐follower tracking control problem for a parameter varying complex interconnected system with directed communication topology and uncertain norm‐bounded coupling between the agents. A gain‐scheduled consensus‐type control protocol is proposed and a sufficient condition is obtained, which guarantees a suboptimal bound on the system tracking performance under this protocol. An interpolation technique is used to obtain a protocol schedule, which is continuous in the scheduling parameter. The effectiveness of the proposed method is demonstrated using a simulation example. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
4.
This paper studies the bipartite output synchronization problem of general linear heterogeneous multiagent systems on signed digraphs. We first show that, for heterogeneous multiagent systems, the bipartite output synchronization over the structurally balanced signed digraphs and the conventional output synchronization over the associated nonnegative digraphs are equivalent. Then, 3 different control protocols, using full‐state feedback, static output feedback, and dynamic output feedback are designed at each agent to solve the bipartite output synchronization problem based on solutions to the corresponding output regulator equations. Explicit local design procedures are proposed for all 3 control protocols. The compensators employed in these protocols incorporate only one copy of the virtual exosystem's dynamics, regardless of the dimensions of the outputs. This results in lower‐dimensional compensators and controllers and, hence, is more computationally tractable compared to the popular internal model principle‐based control protocols. Numerical simulations over 3 different signed communication digraphs validate the proposed control protocols. 相似文献
5.
This paper considers the controllability problem for both continuous- and discrete-time linear heterogeneous multi-agent systems with directed and weighted communication topology. First, two kinds of neighbour-based control protocols based on the distributed protocol of first-order and second-order multi-agent systems are proposed, under which it is shown that a heterogeneous multi-agent system is controllable if the underlying communication topology is controllable. Then, under special leader selection, the result shows that the controllability of a heterogeneous multi-agent system is solely decided by its communication topology graph. Furthermore, some necessary and/or sufficient conditions are derived for controllability of communication topology from algebraic and graphical perspectives. Finally, simulation examples are presented to demonstrate the effectiveness of the theoretical results. 相似文献
6.
In this article, the problem of event‐triggered‐based fixed‐time sliding mode cooperative control is addressed for a class of leader‐follower multiagent networks with bounded perturbation. First, a terminal integral sliding mode manifold with fast convergent speed is designed. Then, a distributed consensus tracking control strategy based on event‐triggered and sliding mode control is developed that guarantees the multiagent networks achieve consensus within a fixed time which is independent of initial states of agents in comparison with the finite‐time convergence. Furthermore, the update frequency of control law can be considerably reduced and Zeno behavior can be removed by utilizing the proposed event‐triggered control algorithm. Simulation examples are used to show the effectiveness of the new control protocol. 相似文献
7.
In this article, the target controllability of multiagent systems under fixed and switching topologies is investigated, respectively. In the fixed topology setting, some necessary and/or sufficient algebraic and graph‐theoretic conditions are proposed, and the target controllable subspace is quantitatively studied by virtue of almost equitable graph vertex partitions. In the switching topology setting, based on the concepts of the invariant subspace and the target controllable state set, some necessary and sufficient algebraic conditions are obtained. Moreover, the target controllability is studied from the union graph perspective. The results show that when the union graph of all the possible topologies is target controllable, the multiagent system would be target controllable even if each of its subsystems is not. Numerical simulations are provided finally to verify the effectiveness of the theoretical results. 相似文献
8.
This paper studies the controllability of multiagent systems based on path and cycle graphs. For paths or cycles, sufficient and necessary conditions are presented for determining the locations of leaders under which the controllability can be realized. Specifically, the controllability of a path is shown to be determined by a set generated only from its odd factors, and the controllability of a cycle is determined by whether the distance between 2 leaders belongs to a set generated from its even (odd) factors when the number of its nodes is even (odd). For both graphs, the dimension of the controllable subspace is also derived. Moreover, the technique used in the derivation of the above results is further used to get sufficient and necessary conditions for several different types of graphs generated from path and cycle topologies. These types of graphs can be regarded as typical topologies in the study of multiagent controllability, and accordingly the obtained results have meaningful enlightenment for the research in this field. 相似文献
9.
This article studies a leader‐following formation control problem, in which the agent model is governed by continuous‐time nonlinear differential equations. We are interested in designing a distributed control algorithm which is capable of handling the strong nonlinearities induced by the unmanned aerial vehicle model. Our primary objective is to investigate the convergence of the corresponding closed‐loop system, and to understand how the nonlinear dynamics and the network topologies may impose intrinsic barriers on formation control. The results show that an exponential convergence is guaranteed under the proposed algorithm via the composite Laplacian quadratics function as long as the network topology has a directed spanning tree. 相似文献
10.
The manipulation of networked cyberphysical devices via local external actuation or feedback control is explored, in the context of a canonical multiagent dynamical system that is engaged in a consensus or synchronization task. One main focus is to understand whether or not, and how easily, a stakeholder can manipulate the full network's dynamics by hijacking only one agent's actuation signal. Explicit spectral characterizations are given of the energy (effort) required to manipulate the dynamics. These characterizations are used to (1) gain structural insights into ease of manipulation, (2) show that manipulation along the consensus manifold is easy, and (3) address network design to enable or prevent manipulation. Additionally, it is shown that the multiagent system can be manipulated effectively along the consensus manifold using local feedback controls, which do not require model knowledge or wide‐area measurements. 相似文献
11.
This paper studies regulated state synchronization for continuous‐time homogeneous multiagent systems with weakly unstable agents where the reference trajectory is given by a so‐called exosystem. The agents share part of their state over a communication network. We assume that the communication topology is completely unknown and directed. An algebraic Riccati equation–based low‐gain adaptive nonlinear dynamic protocol design is presented to achieve the regulated state synchronizations. Utilizing the adaptive control, our nonlinear dynamic protocol is universal and does not depend on any information about the communication topology or the number of agents. 相似文献
12.
The distributed output‐feedback tracking control for a class of networked multiagents in nonaffine pure‐feedback form is investigated in this article. By introducing a low‐pass filter and some auxiliary variables, we first transform the nonaffine system into the affine form. Then, the finite‐time observer is designed to estimate the states of the newly derived affine system. By applying the fraction dynamic surface control approach and the neural network‐based approximation technique, the distributed output‐feedback control laws are proposed and it is proved that the tracking errors converge to an arbitrarily small bound around zero in finite time. Finally, some simulation examples are provided to confirm the effectiveness of the developed method. 相似文献
13.
Guozeng Cui Shengyuan Xu Xinkai Chen Frank L. Lewis Baoyong Zhang 《国际强度与非线性控制杂志
》2018,28(7):2742-2758
》2018,28(7):2742-2758
In this paper, the problem of distributed containment control for pure‐feedback nonlinear multiagent systems under a directed graph topology is investigated. The dynamics of each agent are molded by high‐order nonaffine pure‐feedback form. Neural networks are employed to identify unknown nonlinear functions, and dynamic surface control technique is used to avoid the problem of explosion of complexity inherent in backstepping design procedure. The Frobenius norm of the ideal neural network weighting matrices is estimated, which is helpful to reduce the number of the adaptive tuning law and alleviate the networked communication burden. The proposed distributed containment controllers guarantee that all signals in the closed‐loop systems are cooperatively semiglobally uniformly ultimately bounded, and the outputs of followers are driven into a convex hull spanned by the multiple dynamic leaders. Finally, the effectiveness of the developed method is demonstrated by simulation examples. 相似文献
14.
A new adaptive distributed controller is developed for the leader‐following consensus problem of multiple uncertain Euler‐Lagrange systems. A distinct feature of our proposed approach as opposed to the existing ones is that it does not need the exchange of controller's state among the communication network. As a consequence, it not only makes the implementation of the controller much easier but also reduces the communication cost. The effectiveness of the main result is demonstrated by some exemplary applications to cooperative control of multiple two‐link robot arms. 相似文献
15.
This article proposes a distributed observer and compensation framework to address the synchronization problem of heterogeneous multiagent systems under directed communication and dynamic jointly connected topology scenarios. Different from the previous results, the synchronization problem is solved in our framework which neither relies on the solution of regulator equations which can be regarded as a high gain and usually calculated by a forced equivalence principle, nor assumes the global connectivity condition for all the agents to obtain a bounded synchronization error level. To do this, first, we introduce a dual design principle, where a stabilization condition with an appropriate coupling strength for the synchronization algorithm is proposed. Within this framework, a class of synchronization dynamics called synchronization distributed observers and tracking controller named control protocol are designed. While the synchronization behaviors can be achieved between synchronization distributed observers and control protocol, all the agents will synchronize to their leader in a situation where the system dynamics of the leader can be acquired in advance by all individuals. Finally, simulations of heterogeneous single‐link manipulators are presented to show the effectiveness of our approach. 相似文献
16.
This paper investigates synchronization in leader‐follower networks with varying time‐delay interconnections. In such a network, the leader has its own dynamics and is followed by all the other nodes. Specifically, a variable structure control strategy is developed for the synchronization of the leader‐follower networks based on the Lyapunov stability theory. Copyright © 2009 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society 相似文献
17.
In this paper, the distributed hierarchical control design is investigated for cooperations of heterogeneous linear systems subjected to the switching networks, where each subgraph of switching networks is allowed to be disconnected. Each heterogeneous system contains uncontrollable states and evolves in different dimension with different dynamics. The hierarchical control framework proposed in this paper consists of distributed hierarchical controllers, which contain the upper‐layers dealing with the communication topologies and the lower‐layers dealing with the heterogeneity of the systems. Under the framework, the cooperation problem of heterogeneous linear systems is decoupled into a cooperation problem of homogeneous virtual systems in the upper‐layer and tracking problems of each single systems in the lower‐layer. These two layers are designed based on the optimal control method and the output regulation method, respectively. Under the hierarchical control framework, the leader‐following consensus of heterogeneous linear systems is achieved and the result is extended to the formation control problem. Finally, numerical examples are provided to demonstrate the effectiveness of the theoretical results. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
18.
This paper deals with the leader‐following consensus of discrete‐time multi‐agent systems subject to both position and rate saturation. Each agent is described by a discrete‐time general linear dynamic with actuator subject to position and rate saturation. A modified algebraic Riccati equation and low‐gain feedback design technique are used to construct both state feedback and output feedback control protocols. It is established that a semi‐global leader‐following consensus can be achieved when the system is asymptotically null controllable with bounded controls and a leader agent has a directed path to every follower agent. Finally, several simulations are carried out to illustrate the results. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
19.
This paper is concerned with the problem of fixed‐time consensus tracking control for a class of second‐order multiagent systems under an undirected communication graph. A distributed output‐feedback fixed‐time consensus tracking control scheme is proposed to make the states of all individual agents simultaneously track a time‐varying reference state even when the reference state is available only to a subset of the group members and only output measurements are available for feedback. Homogeneous Lyapunov function and homogeneity property are employed to show that the control scheme can guarantee the consensus tracking errors converging the origin in finite time which is bounded by a fixed constant independent of initial conditions. Numerical simulations are carried out to demonstrate the effectiveness of the proposed control law. 相似文献
20.
For an uncontrollable system, adding leaders and adjusting edge weights are two methods to improve controllability. In this paper, the controllability of multi-agent systems under directed topologies is studied, especially on the leader selection problem and the weight adjustment problem. For a multi-agent system, necessary and sufficient algebraic conditions for controllability with fewest leaders are proposed. To improve controllability by adjusting edge weights, the system is supposed to be structurally controllable, which holds if and only if the communication topology contains a spanning tree. It is also proved that the number of the fewest edges needed to be assigned on new weights equals the rank deficiency of controllability matrix. In addition, a leader selection algorithm and a weight adjustment algorithm are presented. Simulation examples are provided to illustrate the theoretical results. 相似文献