113 research outputs found
Smart home energy management
The new challenges on Information and Communication Technologies (ICT) in Automatic Home
Systems (AHS) focus on the methods useful to monitor, control, and optimize the data management
flow and the use of energy. An AHS is a residential dwelling, in some cases with a garden or
an outdoor space, equipped with sensors and actuators to collect data and send controls according to
the activities and expectations of the occupants/users. Home automation provides a centralized or
distributed control of electrical appliances. Adding intelligence to the home environment, it would
be possible to obtain, not only excellent levels of comfort, but also energy savings both inside and
outside the dwelling, for instance using smart solutions for the management of the external lights and
of the garden
Event-Triggered Algorithms for Leader-Follower Consensus of Networked Euler-Lagrange Agents
This paper proposes three different distributed event-triggered control
algorithms to achieve leader-follower consensus for a network of Euler-Lagrange
agents. We firstly propose two model-independent algorithms for a subclass of
Euler-Lagrange agents without the vector of gravitational potential forces. By
model-independent, we mean that each agent can execute its algorithm with no
knowledge of the agent self-dynamics. A variable-gain algorithm is employed
when the sensing graph is undirected; algorithm parameters are selected in a
fully distributed manner with much greater flexibility compared to all previous
work concerning event-triggered consensus problems. When the sensing graph is
directed, a constant-gain algorithm is employed. The control gains must be
centrally designed to exceed several lower bounding inequalities which require
limited knowledge of bounds on the matrices describing the agent dynamics,
bounds on network topology information and bounds on the initial conditions.
When the Euler-Lagrange agents have dynamics which include the vector of
gravitational potential forces, an adaptive algorithm is proposed which
requires more information about the agent dynamics but can estimate uncertain
agent parameters.
For each algorithm, a trigger function is proposed to govern the event update
times. At each event, the controller is updated, which ensures that the control
input is piecewise constant and saves energy resources. We analyse each
controllers and trigger function and exclude Zeno behaviour. Extensive
simulations show 1) the advantages of our proposed trigger function as compared
to those in existing literature, and 2) the effectiveness of our proposed
controllers.Comment: Extended manuscript of journal submission, containing omitted proofs
and simulation
Distributed Coverage Control of Constrained Constant-Speed Unicycle Multi-Agent Systems
This paper proposes a novel distributed coverage controller for a multi-agent system with constant-speed unicycle robots (CSUR). The work is motivated by the limitation of the conventional method that does not ensure the satisfaction of hard state- and input-dependent constraints and leads to feasibility issues for multi-CSUR systems. In this paper, we solve these problems by designing a novel coverage cost function and a saturated gradient-search-based control law. Invariant set theory and Lyapunov-based techniques are used to prove the state-dependent confinement and the convergence of the system state to the optimal coverage configuration, respectively. The controller is implemented in a distributed manner based on a novel communication standard among the agents. A series of simulation case studies are conducted to validate the effectiveness of the proposed coverage controller in different initial conditions and with control parameters. A comparison study in simulation reveals the advantage of the proposed method in terms of avoiding infeasibility. The experiment study verifies the applicability of the method to real robots with uncertainties. The development procedure of the method from theoretical analysis to experimental validation provides a novel framework for multi-agent system coordinate control with complex agent dynamics
Consensus and synchronization in multi-agent coordination
This thesis considers mainly two topics in the area of multi-agent coordination. The first topic is the consensus and synchronization problem and its extension, where the widely considered models and algorithms in existing studies are revisited. More specifically, for agents with double-integrator dynamics, we consider the design and analysis of the consensus algorithms in a more general framework that agents interact under independent position and velocity network topologies. Both the cases with fixed and switching topologies are considered. While for agents modeled by generic linear system dynamics with static feedback controller, we work on switching interaction topologies. The first of our efforts is trying to relax and extend the assumptions/conditions proposed in existing studies to guarantee the synchronization; the second of our efforts is made towards the specification of the convergence rate under the weakest possible interaction topologies; finally, we attempt to extend the notions of consensus and synchronization as well as containment to the general coordination behavior inherent in networks of diffusively coupled homogeneous agents with arbitrary interaction topology. The second topic is consensus and synchronization for multiple interacting clusters of agents, termed group or cluster consensus and synchronization in existing studies. For this topic, we first revisit the group consensus problem for single-integrator dynamics and try to work out the weakest possible conditions that are necessary to guarantee the group or cluster consensus. We then extend the cooperative and competitive coupling scheme to deal with agents with double-integrator dynamics, for which different group consensus algorithms are proposed to account for different settings in practical applications. That includes agents interacting under respectively the same and different position and velocity interactions, leaderless and leader-following consensus, as well as leaders of constant and time-varying velocities. Finally, we consider the cluster synchronization control for agents with generic linear system dynamics via pinning control techniques under both fixed and switching coupling topologies. Different methodologies, based mainly on the exploration of tools from stability theory for linear systems, algebraic graph theory, as well as matrix analysis, are employed to analyze the algorithms that are proposed in different frameworks. For all such frameworks, we aim at addressing the following two concerns of both theoretical and practical interests: - Whether group or cluster consensus and synchronization can be achieved if the underlying topology of each cluster only has a directed spanning tree and further, the intra-cluster couplings, as compared to the inter-cluster ones, are sufficiently strong? If yes, then how to quantitatively specify the strength? - Under what kind of coupling topologies the group or cluster consensus and synchronization behaviors are irrelevant to the magnitudes of the coupling strengths among the agents
- …