Authors: None

Abstract:

Keywords:

Digital Object Identifier (DOI): 10.3182/20100913-2-FR-4014.90001

Conference: 2nd IFAC Workshop on Distributed Estimation and Control in Networked Systems

Location: Centre de Congrès de L’Impérial Palace, France

Start Date: Mon Sep 13 2010 - End Date: Tue Sep 14 2010

Page Numbers: ---

Authors: Ahmed-Ali, Tarek; Lamnabhi-Lagarrigue, Françoise

Abstract: New results on the emulation of a high gain observers over networks are presented. Using a general framework and a suitable Lyapunov function, some explicit conditions on the maximum allowable transmission interval is given for a large class of network protocols.

Keywords: Coordinated control and estimation over networks; Control with communication constraints (quantization effects etc)

Digital Object Identifier (DOI): 10.3182/20100913-2-FR-4014.00047

Conference: 2nd IFAC Workshop on Distributed Estimation and Control in Networked Systems

Location: Centre de Congrès de L’Impérial Palace, France

Start Date: Mon Sep 13 2010 - End Date: Tue Sep 14 2010

Page Numbers: 145-150

Authors: Andalam, Satya Mohan Vamsi; Elia, Nicola

Abstract: We consider the problem of designing distributed output-feedback controllers that achieve H2 and H_infty performance objectives for a group of plants dynamically interconnected via an arbitrary directed communication network. For a particular class of discrete-time linear time-invariant interconnected systems that are characterized by a structural property of their state-space matrices, we design stabilizing distributed controllers which can use the available network along with the plants of the interconnected system. This is achieved by means of parametrization for the output-feedback linear controllers that linearizes the closed-loop H2 and H_infty norm conditions and provides equivalent linear matrix inequalities (LMIs). Using these LMIs, we formulate the minimization of H2 and H_infty norms as semi-definite programs (SDPs) that can be efficiently solved using well-established and standard techniques and tools. The solutions of these SDPs allow us to synthesize the corresponding controllers that are realizable over the given network. Even though we provide only sufficiency conditions for the design of stabilizing distributed controllers, simulations show that the synthesized controllers we obtain provide good performance in spite of being suboptimal compared to the centralized controller. In essence, we gain the advantage of designing realizable distributed controllers at the expense of some performance degradation compared to the centralized solutions.

Keywords: Decentralized and cooperative optimization; Decentralized algorithms for computation over sensor networks

Digital Object Identifier (DOI): 10.3182/20100913-2-FR-4014.00082

Conference: 2nd IFAC Workshop on Distributed Estimation and Control in Networked Systems

Location: Centre de Congrès de L’Impérial Palace, France

Start Date: Mon Sep 13 2010 - End Date: Tue Sep 14 2010

Page Numbers: 329-334

Authors: Anderson, Brian D.O.; Yu, Changbin (Brad); Dasgupta, Soura; Summers, Tyler H.

Abstract: This paper considers formation shape control of a team of four point agents, for the most part in the plane. Control laws based on specified interagent distances are used. For a complete graph, specification of all interagent distances determines the formation shape uniquely. Krick, Broucke and Francis showed that for a now almost standard control law, there may exist equilibrium formation shapes with incorrect interagent distances. This paper studies such equilibria, shows that in some cases they are necessarily unstable.

Keywords: Coordinated control and estimation over networks

Digital Object Identifier (DOI): 10.3182/20100913-2-FR-4014.00043

Conference: 2nd IFAC Workshop on Distributed Estimation and Control in Networked Systems

Location: Centre de Congrès de L’Impérial Palace, France

Start Date: Mon Sep 13 2010 - End Date: Tue Sep 14 2010

Page Numbers: 139-144

Authors: Bernardini, Daniele; Donkers, Tijs; Bemporad, Alberto; Heemels, Maurice

Abstract: In this paper we present a stochastic model predictive control (SMPC) approach for networked control systems (NCSs) that are subject to time-varying sampling intervals and time-varying transmission delays. These network-induced uncertain parameters are assumed to be described by random processes, having a bounded support and an arbitrary continuous probability density function. Assuming that the controlled plant can be modeled as a linear system, we present a SMPC formulation based on scenario enumeration and quadratic programming that optimizes a stochastic performance index and provides closed-loop stability in the mean-square sense. Simulation results are shown to demonstrate the performance of the proposed approach.

Keywords: Control with communication constraints (quantization effects etc)

Digital Object Identifier (DOI): 10.3182/20100913-2-FR-4014.00007

Conference: 2nd IFAC Workshop on Distributed Estimation and Control in Networked Systems

Location: Centre de Congrès de L’Impérial Palace, France

Start Date: Mon Sep 13 2010 - End Date: Tue Sep 14 2010

Page Numbers: 7-12

Authors: Bishop, Adrian

Abstract: Firstly, an exposition of random-set-based estimation in general networked control systems is examined. This provides a background for the work introduced in this paper. This exposition is also aimed at highlighting the advantages of the random-set-based estimator formulation. Then, the case of state estimation across packet-dropping networks (but with instantaneous transmission times) is shown to be a special case of the standard random-set-based system/measurement model. A well-known result in the control literature concerning the convergence of the Kalman filter's covariance estimate is related to a simplified random-set-based algorithm for this packet-dropping scenario. Finally, a novel algorithm for random-set-based estimation across general networks with irregular measurement sequences (delayed and out-of-sequence measurements) is developed. This is the first attempt to extend random-set-based estimation to accommodate realistic, networked, scenarios.

Keywords: Coordinated control and estimation over networks; Distributed and decentralized signal processing; Decentralized algorithms for computation over sensor networks

Digital Object Identifier (DOI): 10.3182/20100913-2-FR-4014.00010

Conference: 2nd IFAC Workshop on Distributed Estimation and Control in Networked Systems

Location: Centre de Congrès de L’Impérial Palace, France

Start Date: Mon Sep 13 2010 - End Date: Tue Sep 14 2010

Page Numbers: 97-102

Authors: Blackhall, Lachlan; Hill, David J.

Abstract: Results on the joint (or global) controllability of networks of interconnected linear systems using the linear structured systems viewpoint are presented. Criteria to determine the joint structural controllability of a dynamical network using only the local structural controllability properties and the interconnection topology are detailed. These results provide a computationally tractable method of determining the controllability properties of large scale and complex dynamical networks and represent necessary conditions for the controllability, in the usual sense, of dynamical networks. The results hold for networks of structurally reachable linear systems with arbitrary connection topologies.

Keywords: Graph models for networks; Percolation. Network coding

Digital Object Identifier (DOI): 10.3182/20100913-2-FR-4014.00079

Conference: 2nd IFAC Workshop on Distributed Estimation and Control in Networked Systems

Location: Centre de Congrès de L’Impérial Palace, France

Start Date: Mon Sep 13 2010 - End Date: Tue Sep 14 2010

Page Numbers: 245-250

Authors: Bolognani, Saverio; Zampieri, Sandro

Abstract: We consider a distributed system of N agents, on which we define a quadratic optimization problem subject to a linear equality constraint. We assume that the agents can estimate the gradient of the cost function element-wise by measuring the steady state response of the system. Even if the cost function cannot be decoupled into individual terms, and the linear constraint involves the whole system state, we are able to design a distributed, quasi-Newton optimization algorithm. We prove finite time convergence in its centralized version, and by using the tool of average consensus we design its distributed implementation in the case in which a communication graph is given. As a testbed for the proposed method, we consider the problem of optimal distributed reactive power compensation in smart microgrids.

Keywords: Decentralized and cooperative optimization; Decentralized algorithms for computation over sensor networks; Consensus problems

Digital Object Identifier (DOI): 10.3182/20100913-2-FR-4014.00063

Conference: 2nd IFAC Workshop on Distributed Estimation and Control in Networked Systems

Location: Centre de Congrès de L’Impérial Palace, France

Start Date: Mon Sep 13 2010 - End Date: Tue Sep 14 2010

Page Numbers: 305-310

Authors: Brinon Arranz, Lara; Seuret, Alexandre; Canudas de Wit, Carlos

Abstract: This paper deals with the control of a feet of non-linear systems representing AUVs (autonomous underwater vehicles). This paper proposes a novel framework which is able to express in a simple manner the control law for a larger class of formations, including time-varying formations. This has been produced by applying a sequence of affine transformations such as translations, rotations and scalings. A cooperative control law based on consensus algorithms is added to reach the same formation and to achieve the uniform distribution of all the agents along the formation. This is achieved taking into account the communication constraints using a cooperative control which includes the Laplacian matrix of the communication graph. Several simulations are provided to illustrate the convergence.

Keywords: Multivehicle systems, flocking; Coordinated control and estimation over networks; Consensus problems

Digital Object Identifier (DOI): 10.3182/20100913-2-FR-4014.00075

Conference: 2nd IFAC Workshop on Distributed Estimation and Control in Networked Systems

Location: Centre de Congrès de L’Impérial Palace, France

Start Date: Mon Sep 13 2010 - End Date: Tue Sep 14 2010

Page Numbers: 239-244

Authors: Burger, Mernout; Pettersen, Kristin Y.

Abstract: Trajectory tracking and path following both have their benefits, and depending on the mission of a single vehicle or a formation, one may be more favourable than the other. Path manoeuvring can be seen as a combination of both, and has the potential to combine their benefits. We present a method that makes it possible to smoothly change between trajectory tracking, path manoeuvring, and path following; this can be done before or during a mission. The method is presented for both single vehicles and formations. The theoretically obtained results are supported by simulations.

Keywords: Coordinated control and estimation over networks; Multivehicle systems, flocking; Consensus problems

Digital Object Identifier (DOI): 10.3182/20100913-2-FR-4014.00022

Conference: 2nd IFAC Workshop on Distributed Estimation and Control in Networked Systems

Location: Centre de Congrès de L’Impérial Palace, France

Start Date: Mon Sep 13 2010 - End Date: Tue Sep 14 2010

Page Numbers: 115-120

Authors: Cardoso De Castro, Nicolas; Canudas de Wit, Carlos; Johansson, Karl Henrik

Abstract: Energy is a key resource in Networked Control Systems, in particular in applications concerning wireless networks. This paper reviews the multi-layer architecture of those systems in the light of their energy-use, and points out major contributions in the area of energy-management policies, layer per layer. This review of the literature is organized according to the layered communication architecture covering from bottom to top the Physical, Data Link, Network, and Application layers. We specifically focus on advances that concern energy-aware management in wireless communication and control co-design. It is argued that existing work is limited to single layer approaches, with a lack of design methods taking into account several layers.

Keywords: Control with communication constraints (quantization effects etc)

Digital Object Identifier (DOI): 10.3182/20100913-2-FR-4014.00040

Conference: 2nd IFAC Workshop on Distributed Estimation and Control in Networked Systems

Location: Centre de Congrès de L’Impérial Palace, France

Start Date: Mon Sep 13 2010 - End Date: Tue Sep 14 2010

Page Numbers: 49-54

Authors: Cenedese, Angelo; Ghirardello, Riccardo; Guiotto, Roberto; Paggiaro, Fabio; Schenato, Luca

Abstract: In this paper, the problem of building a model of a sensor (camera) network from observations is considered. By model, we mean a graph where the nodes represent states that are observable and distinguishable by the sensor network and edges are the feasible transitions among these states: the edges are also weighted by the probability of transition from one state to another. Remarkably, since merely static observations are not sufficient to discern all states in the networked system, the dynamics of transition is also considered. In this respect, the proposed graph model appears falling into the class of hidden Markov models, where the discover of hidden states is made possible by exploiting the temporal evolution of the transitions and the implementation of a splitting procedure of previously identified graph nodes.

Keywords: Graph models for networks; Percolation. Network coding; Decentralized algorithms for computation over sensor networks; Decentralized and cooperative optimization

Digital Object Identifier (DOI): 10.3182/20100913-2-FR-4014.00056

Conference: 2nd IFAC Workshop on Distributed Estimation and Control in Networked Systems

Location: Centre de Congrès de L’Impérial Palace, France

Start Date: Mon Sep 13 2010 - End Date: Tue Sep 14 2010

Page Numbers: 299-304

Authors: Chávez Grunewald, Martín Guillermo; Ben Makhlouf, Ibtissem; Diab, Hilal; Abel, Dirk; Kowalewski, Stefan

Abstract: In this paper, the design of an energy-based controller for a platoon of nonholonomic vehicles is presented and its performance is analysed for the case of random time delays in the network. The nonholonomic constraints of the models are taken into account during the design process by considering them in the goal virtual Lagrange function. The introductory section gives an overview of the energy methods for the case of mass point vehicles. Subsequently, the strategy is extended to apply to the case of nonholonomic vehicles. The controller is analysed by means of simulation tools in order to evaluate the effects of random Rayleigh distributed delays on the network.

Keywords: Multivehicle systems, flocking; Coordinated control and estimation over networks

Digital Object Identifier (DOI): 10.3182/20100913-2-FR-4014.00011

Conference: 2nd IFAC Workshop on Distributed Estimation and Control in Networked Systems

Location: Centre de Congrès de L’Impérial Palace, France

Start Date: Mon Sep 13 2010 - End Date: Tue Sep 14 2010

Page Numbers: 169-174

Authors: Chiuso, Alessandro; Fagnani, Fabio; Schenato, Luca; Zampieri, Sandro

Abstract: In this work we consider the problem of simultaneously classifying sensor types and estimating hidden parameters in a network of sensors subject to gossip-like communication limitations. In particular, we consider a network of scalar noisy sensors which measure a common unknown parameter. We assume that a fraction of the nodes is subject to the same (but possibly unknown) offset. The goal for each node is to simultaneously identify the class the node belongs to and to estimate the common unknown parameter, only through local communication and computation. We propose a distributed estimator based on the maximum likelihood (ML) approach and we show that, in case the offset is known, this estimator converges to the centralized ML as the number N of sensor nodes goes to infinity. We also compare this strategy with a distributed implementation of estimation-maximization (EM) algorithm; we show tradeoffs via numerical simulations in terms of robustness, speed of convergence and implementation simplicity.

Keywords: Distributed and decentralized signal processing; Decentralized algorithms for computation over sensor networks; Consensus problems

Digital Object Identifier (DOI): 10.3182/20100913-2-FR-4014.00045

Conference: 2nd IFAC Workshop on Distributed Estimation and Control in Networked Systems

Location: Centre de Congrès de L’Impérial Palace, France

Start Date: Mon Sep 13 2010 - End Date: Tue Sep 14 2010

Page Numbers: 281-286

Authors: De Persis, Claudio; Cao, Ming

Abstract: In this paper, we study the formation control problem for platoons of mobile agents that are guided by coarsely quantized information. A comprehensive trajectory-based analysis is presented for the convergence of the multi-agent platoon, which greatly improves the existing result that applies only to 3-agent platoons. Using tools from non-smooth analysis, it is shown that the formation can converge within finite time even when each agent is constrained by a 1-bit transmission channel. We further introduce hysteresis in the quantization scheme to deal with the possible chattering phenomena as a result of the coarse quantization. Simulation results validate the effectiveness of the proposed control strategy.

Keywords: Control with communication constraints (quantization effects etc)

Digital Object Identifier (DOI): 10.3182/20100913-2-FR-4014.00030

Conference: 2nd IFAC Workshop on Distributed Estimation and Control in Networked Systems

Location: Centre de Congrès de L’Impérial Palace, France

Start Date: Mon Sep 13 2010 - End Date: Tue Sep 14 2010

Page Numbers: 25-30

Authors: Dekker, Gerrit Willem; Jokic, Andrej; Weiland, Siep

Abstract: We consider the optimal network frequency control in electrical power systems. The overall power system consists of several subsystems distributed over a network. We implement a method of synthesizing a distributed dynamic output feedback controller (Langbort et al., 2004a) for such a system consisting of several subsystems distributed over an arbitrary graph. This H-infinity-based distributed approach is then compared with the classical AGC controller, the centralized H-infinity solution and different MPC approaches.

Keywords: Control with communication constraints (quantization effects etc)

Digital Object Identifier (DOI): 10.3182/20100913-2-FR-4014.00027

Conference: 2nd IFAC Workshop on Distributed Estimation and Control in Networked Systems

Location: Centre de Congrès de L’Impérial Palace, France

Start Date: Mon Sep 13 2010 - End Date: Tue Sep 14 2010

Page Numbers: 19-24

Authors: Dorfler, Florian; Bullo, Francesco

Abstract: In transient stability studies in power networks two types of mathematical models are commonly used -- the differential-algebraic structure-preserving model and the reduced dynamic model of interconnected swing equations. This paper analyzes the reduction process relating the two power network models. The reduced admittance matrix is obtained by a Schur complement of the topological network admittance matrix with respect to its bus nodes. We provide a detailed spectral, algebraic, and graph-theoretic analysis of this network reduction process, termed Kron reduction, with particular focus on the effective resistance. As an application of this analysis, we are able to state concise conditions relating synchronization in the considered structure-preserving power network model directly to the state, parameters, and topology of the underlying network. In particular, we provide a spectral condition based on the algebraic connectivity of the network and a second condition based on the effective resistance among generators.

Keywords: Graph models for networks; Percolation. Network coding; Consensus problems

Digital Object Identifier (DOI): 10.3182/20100913-2-FR-4014.00048

Conference: 2nd IFAC Workshop on Distributed Estimation and Control in Networked Systems

Location: Centre de Congrès de L’Impérial Palace, France

Start Date: Mon Sep 13 2010 - End Date: Tue Sep 14 2010

Page Numbers: 197-202

Authors: Fischione, Carlo; D'Angelo, Massimiliano

Abstract: The problem of maximizing a utility function while limiting the outage probability below an appropriate threshold is investigated. A coded-division multi access wireless network under mixed Nakagami-lognormal fading is considered. Solving such a utility maximization problem is difficult because the problem is non-convex and non-geometric with mixed integer and real decision variables and no explicit functions of the constraints are available. In this paper, two methods to the solution of the utility maximization problem are proposed. By the first method, a simple explicit outage approximation is used and the constraint that rates are integers is relaxed yielding a standard convex programming optimization that can be solved quickly but at the price of a reduced accuracy. The second method uses a more accurate outage approximation, which allows one solving the utility maximization problem by the Lagrange duality for non-convex problems and contraction mapping theory. Numerical results show that the first method performs well for average values of the outage requirements, whereas the second one is always more accurate, but is also more computationally expensive.

Keywords: Control with communication constraints (quantization effects etc); Coordinated control and estimation over networks

Digital Object Identifier (DOI): 10.3182/20100913-2-FR-4014.00037

Conference: 2nd IFAC Workshop on Distributed Estimation and Control in Networked Systems

Location: Centre de Congrès de L’Impérial Palace, France

Start Date: Mon Sep 13 2010 - End Date: Tue Sep 14 2010

Page Numbers: 133-138

Authors: Ghasemi, Nader; Dey, Subhrakanti; Baras, John S.

Abstract: In this paper, we study almost sure convergence of a dynamic average consensus algorithm which allows distributed computation of the product of n time-varying conditional probability density functions. These density functions (often called as “belief functions”) correspond to the conditional probability of observations given the state of an underlying Markov chain, which is observed by n different nodes within a sensor network. The topology of the sensor network is modeled as an undirected graph. The average consensus algorithm is used to obtain a distributed state estimation scheme for a hidden Markov model (HMM). We use the ordinary differential equation (ODE) technique to analyze the convergence of a stochastic approximation type algorithm for achieving average consensus with a constant step size. It is shown that, for a connected graph, under mild assumptions on the first and second moments of the observation probability densities and a geometric ergodicity condition on an extended Markov chain, the consensus filter state of each individual sensor converges almost surely to the true average of the logarithm of the belief functions of all the sensors. Convergence is proved by using a perturbed stochastic Lyapunov function technique. Numerical results suggest that the distributed estimates of the Markov chain state obtained at the individual sensor nodes based on this consensus algorithm track the centralized state estimate (computed on the basis of having access to the observations of all the nodes) quite well, while more formal results on convergence of the distributed HMM filter to the centralized one are currently under investigation.

Keywords: Consensus problems; Decentralized algorithms for computation over sensor networks; Randomized algorithms, gossip algorithms

Digital Object Identifier (DOI): 10.3182/20100913-2-FR-4014.00083

Conference: 2nd IFAC Workshop on Distributed Estimation and Control in Networked Systems

Location: Centre de Congrès de L’Impérial Palace, France

Start Date: Mon Sep 13 2010 - End Date: Tue Sep 14 2010

Page Numbers: 335-340

Authors: Goldin, Darina; Raisch, Joerg

Abstract: In this paper we study formation control of a network of communicating mobile agents with double integrator dynamics. All agents run a consensus algorithm, several leader agents are further subject to an external input. We put this problem in a control theoretical framework and show that the controllability of the entire system via external control input depends only on the controllability of the follower system through the leaders. We then show necessary and sufficient conditions for the follower system to be controllable and relate the obtained conditions to the existing results on topological properties of the follower communication graph.

Keywords: Consensus problems; Multivehicle systems, flocking; Coordinated control and estimation over networks

Digital Object Identifier (DOI): 10.3182/20100913-2-FR-4014.00074

Conference: 2nd IFAC Workshop on Distributed Estimation and Control in Networked Systems

Location: Centre de Congrès de L’Impérial Palace, France

Start Date: Mon Sep 13 2010 - End Date: Tue Sep 14 2010

Page Numbers: 233-238

Authors: Gupta, Vijay; Quevedo, Daniel E.

Abstract: We present an algorithm to calculate the control input when the processing resources available are time-varying. The basic idea is to calculate the control input to decrease the Lyapunov function value as compared to as many time steps in the past as allowed by the available processing resources at every time step. We analyze the stability of the resulting closed loop system using stochastic Lyapunov functions and indicate through numerical simulations that the increase in performance due to the proposed algorithm can be significant.

Keywords: Coordinated control and estimation over networks

Digital Object Identifier (DOI): 10.3182/20100913-2-FR-4014.00004

Conference: 2nd IFAC Workshop on Distributed Estimation and Control in Networked Systems

Location: Centre de Congrès de L’Impérial Palace, France

Start Date: Mon Sep 13 2010 - End Date: Tue Sep 14 2010

Page Numbers: 85-90

Authors: Heemels, Maurice; Merry, Roel; Oomen, Tom

Abstract: In this paper alternative frequency-domain criteria are provided for the stability of discrete-time networked control systems with time-varying delays. These criteria are in various situations less conservative than the existing frequency-domain conditions as is demonstrated by means of an example. In addition, new stability conditions are presented that allow for multiple sensor-to-controller and controller-to-actuator channels exhibiting different delay characteristics. The stability conditions are formulated in terms of the H_infinity norm and the structured singular value. As a result, the obtained results can be used directly for controller synthesis via standard robust control techniques.

Keywords: Control with communication constraints (quantization effects etc)

Digital Object Identifier (DOI): 10.3182/20100913-2-FR-4014.00067

Conference: 2nd IFAC Workshop on Distributed Estimation and Control in Networked Systems

Location: Centre de Congrès de L’Impérial Palace, France

Start Date: Mon Sep 13 2010 - End Date: Tue Sep 14 2010

Page Numbers: 73-78

Authors: Hetel, Laurentiu; Daafouz, Jamal; Jungers, Marc; Richard, Jean-Pierre

Abstract: In this paper the sampled-data stabilization of linear time-invariant systems with feedback delay is considered. We assume that the delay is time-varying and that its value is approximatively known. We investigate how to use the available information about the evolution of delays for adapting the control law. Numerical methods for the design of a delay-dependent controller are presented. This procedure may be used for providing a control for some cases in which the stabilization cannot be ensured using a controller with a fixed structure.

Keywords: Control with communication constraints (quantization effects etc)

Digital Object Identifier (DOI): 10.3182/20100913-2-FR-4014.00033

Conference: 2nd IFAC Workshop on Distributed Estimation and Control in Networked Systems

Location: Centre de Congrès de L’Impérial Palace, France

Start Date: Mon Sep 13 2010 - End Date: Tue Sep 14 2010

Page Numbers: 37-42

Authors: Hurak, Zdenek; Sebek, Michael

Abstract: This paper formulates the problems of stability testing and stabilization of an infinite platoon of vehicles within the 2D polynomial framework, that is, the dynamics of the problem is described using a fraction of two bivariate polynomials. Recent computational tools for testing positivity of polynomial matrices are suggested for stability testing and stabilization.

Keywords: Multivehicle systems, flocking; Coordinated control and estimation over networks; Decentralized algorithms for computation over sensor networks

Digital Object Identifier (DOI): 10.3182/20100913-2-FR-4014.00071

Conference: 2nd IFAC Workshop on Distributed Estimation and Control in Networked Systems

Location: Centre de Congrès de L’Impérial Palace, France

Start Date: Mon Sep 13 2010 - End Date: Tue Sep 14 2010

Page Numbers: 227-232

Authors: Ishido, Yumiko; Quevedo, Daniel E.; Takaba, Kiyotsugu

Abstract: In this paper, we study the stability of a networked control system involving signal quantization with finitely many levels and a bounded number of consecutive packet-dropouts. To compensate for the effect of packet-dropouts, the controller-encoder sends a packet which contains possible quantized control inputs for a bounded number of future steps. At the receiving end, i.e., at the plant actuator side, a buffer decides the actuator input based on the received data. The buffer has memory which is overwritten whenever it receives a packet from the controller. Within this setting, we derive a sufficient condition on quantization parameters for achieving small l-infinity signal l-infinity stability of the feedback system. The stability condition is characterized in terms of the number of quantization levels of the quantizer.

Keywords: Control with communication constraints (quantization effects etc)

Digital Object Identifier (DOI): 10.3182/20100913-2-FR-4014.00035

Conference: 2nd IFAC Workshop on Distributed Estimation and Control in Networked Systems

Location: Centre de Congrès de L’Impérial Palace, France

Start Date: Mon Sep 13 2010 - End Date: Tue Sep 14 2010

Page Numbers: 43-48