19 research outputs found
Designing Fully Distributed Consensus Protocols for Linear Multi-agent Systems with Directed Graphs
This paper addresses the distributed consensus protocol design problem for
multi-agent systems with general linear dynamics and directed communication
graphs. Existing works usually design consensus protocols using the smallest
real part of the nonzero eigenvalues of the Laplacian matrix associated with
the communication graph, which however is global information. In this paper,
based on only the agent dynamics and the relative states of neighboring agents,
a distributed adaptive consensus protocol is designed to achieve
leader-follower consensus for any communication graph containing a directed
spanning tree with the leader as the root node. The proposed adaptive protocol
is independent of any global information of the communication graph and thereby
is fully distributed. Extensions to the case with multiple leaders are further
studied.Comment: 16 page, 3 figures. To appear in IEEE Transactions on Automatic
Contro
Distributed Consensus of Linear Multi-Agent Systems with Adaptive Dynamic Protocols
This paper considers the distributed consensus problem of multi-agent systems
with general continuous-time linear dynamics. Two distributed adaptive dynamic
consensus protocols are proposed, based on the relative output information of
neighboring agents. One protocol assigns an adaptive coupling weight to each
edge in the communication graph while the other uses an adaptive coupling
weight for each node. These two adaptive protocols are designed to ensure that
consensus is reached in a fully distributed fashion for any undirected
connected communication graphs without using any global information. A
sufficient condition for the existence of these adaptive protocols is that each
agent is stabilizable and detectable. The cases with leader-follower and
switching communication graphs are also studied.Comment: 17 pages, 5 figue
Adaptive Second-Order Synchronization of Two Heterogeneous Nonlinear Coupled Networks
This paper investigates the second-order synchronization of two heterogeneous
nonlinear coupled networks by introducing controller and adaptive laws. Based
on Lyapunov stability properties and LaSalle invariance principle, it is proved that
the position and the velocity of two heterogeneous nonlinear coupled networks are
asymptotically stable. Finally, some numerical simulations are presented to verify
the analytical results
Distributed sampled-data control of nonholonomic multi-robot systems with proximity networks
This paper considers the distributed sampled-data control problem of a group
of mobile robots connected via distance-induced proximity networks. A dwell
time is assumed in order to avoid chattering in the neighbor relations that may
be caused by abrupt changes of positions when updating information from
neighbors. Distributed sampled-data control laws are designed based on nearest
neighbour rules, which in conjunction with continuous-time dynamics results in
hybrid closed-loop systems. For uniformly and independently initial states, a
sufficient condition is provided to guarantee synchronization for the system
without leaders. In order to steer all robots to move with the desired
orientation and speed, we then introduce a number of leaders into the system,
and quantitatively establish the proportion of leaders needed to track either
constant or time-varying signals. All these conditions depend only on the
neighborhood radius, the maximum initial moving speed and the dwell time,
without assuming a prior properties of the neighbor graphs as are used in most
of the existing literature.Comment: 15 pages, 3 figure
Fully Distributed Adaptive Controllers for Cooperative Output Regulation of Heterogeneous Linear Multi-agent Systems with Directed Graphs
This paper considers the cooperative output regulation problem for linear
multi-agent systems with a directed communication graph, heterogeneous linear
subsystems, and an exosystem whose output is available to only a subset of
subsystems. Both the cases with nominal and uncertain linear subsystems are
studied. For the case with nominal linear subsystems, a distributed adaptive
observer-based controller is designed, where the distributed adaptive observer
is implemented for the subsystems to estimate the exogenous signal. For the
case with uncertain linear subsystems, the proposed distributed observer and
the internal model principle are combined to solve the robust cooperative
output regulation problem. Compared with the existing works, one main
contribution of this paper is that the proposed control schemes can be designed
and implemented by each subsystem in a fully distributed fashion for general
directed graphs. For the special case with undirected graphs, a distributed
output feedback control law is further presented.Comment: 8 pages, 2 figures. submitted for publicatio