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1.
Distributed formation control for a multi-agent system with dynamic and static obstacle avoidances 下载免费PDF全文
Formation control and obstacle avoidance for multi-agent systems have attracted more and more attention. In this paper, the problems of formation control and obstacle avoidance are investigated by means of a consensus algorithm. A novel distributed control model is proposed for the multi-agent system to form the anticipated formation as well as achieve obstacle avoidance. Based on the consensus algorithm, a distributed control function consisting of three terms(formation control term, velocity matching term, and obstacle avoidance term) is presented. By establishing a novel formation control matrix, a formation control term is constructed such that the agents can converge to consensus and reach the anticipated formation. A new obstacle avoidance function is developed by using the modified potential field approach to make sure that obstacle avoidance can be achieved whether the obstacle is in a dynamic state or a stationary state. A velocity matching term is also put forward to guarantee that the velocities of all agents converge to the same value. Furthermore, stability of the control model is proven. Simulation results are provided to demonstrate the effectiveness of the proposed control. 相似文献
2.
This paper investigates a new formation motion problem of a class of first-order multi-agent systems with antagonistic interactions.A distributed formation control algorithm is proposed for each agent to realize the antagonistic formation motion.A sufficient condition is derived to ensure that all of the agents make an antagonistic formation motion in a distributed manner.It is shown that all of the agents can be spontaneously divided into several groups and that agents in the same group collaborate while agents in different groups compete.Finally,a numerical simulation is included to demonstrate our theoretical results. 相似文献
3.
The threshold current is analyzed for distributed feedback (DFB) and distributed Bragg reflector (DBR) semiconductor lasers with circular gratings. It is shown that in circular grating DFB lasers, the threshold current becomes minimum at a certain cavity radius, while in circular grating DBR lasers it increases monotonically as the active region radius increases. 相似文献
4.
This paper is concerned with the stochastic bounded consensus tracking problems of leader–follower multi-agent systems, where the control input of an agent can only use the information measured at the sampling instants from its neighborhood agents or a virtual leader with a time-varying reference state, the measurements are corrupted by random noises, and the signal sampling process induces a small sampling delay. The augmented matrix method, probability limit theory and algebra graph theory are employed to derive the necessary and sufficient conditions guaranteeing mean square bounded consensus tracking. It turns out that the convergence of the proposed protocol simultaneously depends on the constant feedback gains, the network topology, the sampling period and the sampling delay, and that the static consensus tracking error depends on not only the above-mentioned factors, but also the noise intensity, the number of agents and the upper bound of the changing rate of the virtual leader’s state. The obtained results cover no sampling delay as a special case. Simulations are provided to demonstrate the effectiveness of the theoretical results. 相似文献
5.
This paper introduces the concept of linear-control-based
synchronization of coexisting attractor networks with time delays.
Within the new framework, closed loop control for each dynamic node
is realized through linear state feedback around its own arena in a
decentralized way, where the feedback matrix is determined through
consideration of the coordination of the node dynamics, the
inner connected matrix and the outer connected matrix. Unlike
previously existing results, the feedback gain matrix here is decoupled
from the inner matrix; this not only guarantees the flexible choice
of the gain matrix, but also leaves much space for inner matrix
configuration. Synchronization of coexisting attractor networks with
time delays is made possible in virtue of local interaction, which
works in a distributed way between individual neighbours, and the
linear feedback control for each node. Provided that the network is
connected and balanced, synchronization will come true naturally,
where theoretical proof is given via a Lyapunov function. For
completeness, several illustrative examples are presented to further
elucidate the novelty and efficacy of the proposed scheme. 相似文献
6.
Dynamics of majority rule in two-state interacting spin systems 总被引:2,自引:0,他引:2
We introduce a two-state opinion dynamics model where agents evolve by majority rule. In each update, a group of agents is specified whose members then all adopt the local majority state. In the mean-field limit, where a group consists of randomly selected agents, consensus is reached in a time that scales ln(N, where N is the number of agents. On finite-dimensional lattices, where a group is a contiguous cluster, the consensus time fluctuates strongly between realizations and grows as a dimension-dependent power of N. The upper critical dimension appears to be larger than 4. The final opinion always equals that of the initial majority except in one dimension. 相似文献
7.
This paper introduces the concept of linear-control-based synchronization of coexisting attractor networks with time delays.Within the new framework,closed loop control for each dynamic node is realized through linear state feedback around its own arena in a decentralized way,where the feedback matrix is determined through consideration of the coordination of the node dynamics,the inner connected matrix and the outer connected matrix.Unlike previously existing results,the feedback gain matrix here is decoupled from the inner matrix;this not only guarantees the flexible choice of the gain matrix,but also leaves much space for inner matrix configuration.Synchronization of coexisting attractor networks with time delays is made possible in virtue of local interaction,which works in a distributed way between individual neighbours,and the linear feedback control for each node.Provided that the network is connected and balanced,synchronization will come true naturally,where theoretical proof is given via a Lyapunov function.For completeness,several illustrative examples are presented to further elucidate the novelty and efficacy of the proposed scheme. 相似文献
8.
YUAN XueGang ZHANG HongWu ZHANG WenZheng ZHAO Wei & Dong Bin School of Science Dalian Nationalities University Dalian China State Key Laboratory of Structural Analysis for Industrial Equipment 《中国科学:物理学 力学 天文学(英文版)》2011,(2)
A class of dynamic cavitations is examined for an isotropic incompressible hyperelastic circular sheet under a pre-strained state caused by an initially applied finite radial tension.The solutions that describe the radially symmetric motion of the pre-strained sheet are obtained.The conditions of cavitated bifurcation that describe cavity formation and motion with time at the axial line of the pre-strained sheet are proposed,that is to say,a circular cavity will form if the suddenly applied radial tensile l... 相似文献
9.
10.
X. Castelló A. Baronchelli V. Loreto 《The European Physical Journal B - Condensed Matter and Complex Systems》2009,71(4):557-564
We consider two social consensus models, the AB-model and
the Naming Game restricted to two conventions, which describe a
population of interacting agents that can be in either of two
equivalent states (A or B) or in a third mixed (AB) state. Proposed
in the context of language competition and emergence, the AB state
was associated with bilingualism and synonymy respectively. We show
that the two models are equivalent in the mean field approximation,
though the differences at the microscopic level have non-trivial
consequences. To point them out, we investigate an extension of
these dynamics in which confidence/trust is considered, focusing on
the case of an underlying fully connected graph, and we show that
the consensus-polarization phase transition taking place in the
Naming Game is not observed in the AB model. We then consider the
interface motion in regular lattices. Qualitatively, both models
show the same behavior: a diffusive interface motion in a
one-dimensional lattice, and a curvature driven dynamics with
diffusing stripe-like metastable states in a two-dimensional
one. However, in comparison to the Naming Game, the AB-model
dynamics is shown to slow down the diffusion of such configurations. 相似文献
11.
Quantum state sharing of an arbitrary two-qubit state
with two-photon entanglements and Bell-state measurements 总被引:4,自引:0,他引:4
F.-G. Deng X.-H. Li C.-Y. Li P. Zhou H.-Y. Zhou 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2006,39(3):459-464
Two schemes for sharing an arbitrary two-qubit state based on
entanglement swapping are proposed with Bell-state measurements
and local unitary operations. One is based on the quantum channel
with four Einstein-Podolsky-Rosen (EPR) pairs shared in advance.
The other is based on a circular topological structure, i.e., each
user shares an EPR pair with his neighboring one. The advantage of
the former is that the construction of the quantum channel between
the agents is controlled by the sender Alice, which will improve
the security of the scheme. The circular scheme reduces the
quantum resource largely when the number of the agents is large.
Both of those schemes have the property of high efficiency as
almost all the instances can be used to split the quantum
information. They are more convenient in application than the
other schemes existing as they require only two-qubit
entanglements and two-qubit joint measurements for sharing an
arbitrary two-qubit state. 相似文献
12.
13.
We study the consensus problem in a weighted and directed network composed of self-propelled agents. The weight which quantifies the relationship between the agents is adjusted according to their state incoherence to suppress the heterogeneity in state. The proposed consensus protocol enhances the convergence efficiency of consensus greatly and has better performance than that of two other protocols. The convergence efficiency can be further improved by adjusting the parameter of this protocol. Furthermore, the robustness of the system against coupling time-delay is significantly increased. Unlike most consensus acceleration methods, no topological information is needed in our model. Networks with different stuctures are investigated to demonstrate the generality of the method. 相似文献
14.
We investigate the finite-time consensus problem for heterogeneous multi-agent systems composed of first-order and second-order agents.A novel continuous nonlinear distributed consensus protocol is constructed,and finite-time consensus criteria are obtained for the heterogeneous multi-agent systems.Compared with the existing results,the stationary and kinetic consensuses of the heterogeneous multi-agent systems can be achieved in a finite time respectively.Moreover,the leader can be a first-order or a second-order integrator agent.Finally,some simulation examples are employed to verify the efficiency of the theoretical results. 相似文献
15.
Distance-based formation tracking control of multi-agent systems with double-integrator dynamics 下载免费PDF全文
This paper addresses the distance-based formation tracking problem for a double-integrator modeled multi-agent system(MAS) in the presence of a moving leader in d-dimensional space. Under the assumption that the state of leader can be obtained over fixed graphs, a distributed distance-based control protocol is designed for each double-integrator follower agent. The protocol consists of three terms: a gradient function term, a velocity consensus term, and a leader tracking term.Different shape stabilizing functions proposed in the literature can be applied to the gradient function term. The proposed controller allows all agents to both achieve the desired shape and reach the same velocity with moving leader by controlling the distances and velocity. Finally, we analyze the local asymptotic stability of the equilibrium set with center manifold theory. We validate the effectiveness of our approach through two examples. 相似文献
16.
A general stability study of equatorial circular orbits in static axially symmetric gravitating systems is presented. We investigate the motion of neutral test particles in circular geodesics such as the marginally stable orbit, the marginally bounded orbit, and the photon orbit are analyzed. We find general expressions for the radius, specific energy, specific angular momentum, and the radius of the marginally stable orbit, both for null and timelike circular geodesics. Different solutions were expressed in different coordinates systems: cylindrical coordinates, oblate spheroidal coordinates, and prolate spheroidal coordinates are considered. We show that all null circular trajectories are unstable, and that there aren’t marginally stable null geodesics, whereas for timelike geodesics the motion can be unbounded, bounded, or circular. 相似文献
17.
The present article reviews the fundamental physical principles essential to an understanding of waveguide gas and liquid
lasers, and the current technological state of these devices. At the present time, waveguide laser transitions span the visible
through submillimeter regions of the wavelength spectrum. The introduction discusses the many applications of waveguide lasers
and the wide variety of laser configurations that are possible. Section 1 summarizes the properties of modes in hollow dielectric
waveguides of circular, rectangular, and planar cross section. Section 2 considers various approaches to optical feedback
including internal and external mirror Fabry-Perot type resonators, hollow waveguide distributed feedback structures, and
ring-resonant configurations. Section 3 discusses those aspects of molecular kinetic and laser theory pertinent to the design
and optimization of waveguide gas lasers such as the scaling laws for discharge-excited gas lasers, molecular models useful
in maximizing the oscillation bandwidth, the effects of gas flow rate, and the physics of optically-pumped far-infrared lasers.
Finally, a review of the waveguide gas and liquid lasers reported to date is given in Section 4. 相似文献
18.
This paper deals with the consensus problem for heterogeneous multi-agent systems. Different from most existing consensus protocols, we consider the consensus seeking of two types of agents, namely, active agents and passive agents. The objective is to directly control the active agents such that the states of all the agents would achieve consensus. In order to obtain a computational approach, we subtly introduce an appropriate Markov chain to cast the heterogeneous systems into a unified framework. Such a framework is helpful for tackling the constraints from passive agents. Furthermore, a sufficient and necessary condition is established to guarantee the consensus in heterogeneous multi-agent systems. Finally, simulation results are provided to verify the theoretical analysis and the effectiveness of the proposed protocol. 相似文献
19.
Spontaneous excitation of a circularly accelerated atom coupled with vacuum Dirac field fluctuations
We study the spontaneous excitation of a circularly accelerated atom coupled with vacuum Dirac field fluctuations by separately calculating the contribution to the excitation rate of vacuum fluctuations and a cross term which involves both vacuum fluctuations and radiation reaction, and demonstrate that although the spontaneous excitation for the atom in its ground state would occur in vacuum, such atoms in circular motion do not perceive a pure thermal radiation as their counterparts in linear acceleration do since the transition rates of the atom do not contain the Planckian factor characterizing a thermal bath. We also find that the contribution of the cross term that plays the same role as that of radiation reaction in the scalar and electromagnetic fields cases differs for atoms in circular motion from those in linear acceleration. This suggests that the conclusion drawn for atoms coupled with the scalar and electromagnetic fields that the contribution of radiation reaction to the mean rate of change of atomic energy does not vary as the trajectory of the atom changes from linear acceleration to circular motion is not a general trait that applies to the Dirac field where the role of radiation reaction is played by the cross term. 相似文献
20.
This paper investigates the leader-following tracking consensus problem for second-order multi-agent systems with time delays and nonlinear dynamics in noisy environments on the conditions of fixed and switching directed topologies. Based on a novel velocity decomposition technique and stochastic analysis, a measurement-based distributed tracking control protocol is proposed, under which all agents can track the leader in mean square. Simulation results are also given to illustrate the effectiveness of the proposed protocol. 相似文献