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This paper is concerned with the collective behavior of a group of n > 1 mobile autonomous agents, labelled 1 through n, which can all move in the plane. Each agent is able to continuously track the positions of all other agents currently within its “sensing region” where by an agent’s sensing region is meant a closed disk of positive radius r centered at the agent’s current position....
We consider generalized linear dynamic factor models. These models have been developed recently and they are used for high dimensional time series in order to overcome the “curse of dimensionality”. We present a structure theory with emphasis on the zeroless case, which is generic in the setting considered. Accordingly the latent variables are modeled as a possibly singular autoregressive process...
Consider a network of sensors able to move in 2-dimensional space. We may aim to impose distance constraints between certain sensors to ensure every pair of sensors maintain their distance from one another under any continuous movement. This property is known as rigidity. Rigidity may be required to ensure that no sensor will move out of range of any other sensor during movement. However, there arise...
Location information for sensors in wireless sensor networks (WSNs) is essential to many tasks. If sensors are mobile and are to be controlled to certain locations, localizability is indispensable. In a noisy environment, locations must be estimated, and the question of location error and its magnitude becomes important. Error is a function of the positioning and density of anchors in a WSN, and the...
In passive target localization using direction finding (DF), there are particular sensor-target placements that cause large biases in the estimates or the failure of estimates to converge to a unique solution. Identification of such problematic configurations is crucial for implementing estimation and tracking algorithms effectively. In this paper we propose four methods for characterizing near-collinearity...
A framework for addressing a potential instability problem in adaptive control and iterative identification and controller design algorithms is proposed. Suppose an unknown plant is stabilized by a known controller, some knowledge of this stable closed-loop system is available, and the use of a new controller to replace the current stabilizing controller becomes imminent. Our analysis results assume...
This paper considers formation shape control of a team of four agents in the plane, motivated by an example from [1]. We utilize bidirectional, gradient-based interagent distance control laws which are designed so that the agents cooperatively achieve a specified desired formation shape. When every interagent distance is actively controlled (i.e. the information architecture is a complete graph),...
This paper addresses the n-agent formation shape maintenance problem in the plane. We consider a class of directed information architectures associated with so called minimally persistent coleader formations. The formation shape is specified by certain interagent distances. Only one agent is responsible for maintaining each distance. We propose a control law where each agent executes its control using...
The system multi-realization problem is to find a state-variable realization for a set of systems, sharing as many parameters as possible. A multi-realization can be used to efficiently implement a multi-controller architecture for Multiple Model Adaptive Control (MMAC). We extend the linear multi-realization problem to nonlinear systems. The problem of minimal multi-realization of a set of MIMO systems...
This paper investigates accelerated gossip algorithms for distributed computations in networks where shift-registers are utilized at each node. By using tools from matrix analysis, we prove the existence of the desired acceleration and establish the fastest rate of convergence in expectation for two-register symmetric gossip. Some classes of networks with regular graph topologies are studied in detail...
A novel dwell-time-switching based multiple model adaptive control (MMAC) scheme is proposed for the state feedback stabilization problem of a class of general nonlinear systems with nonlinear parameterization. One major contribution is that it has advanced Morse's dwell-time-switching from linear systems to a class of nonlinear systems. Another significant contribution is that it combines the idea...
This paper deals with autoregressive models of singular spectra. The starting point is the assumption that there is available a transfer function matrix W(q) expressible in the form D-1(q)B for some tall constant matrix B of full column rank and with the determinantal zeros of D(q) all stable. It is shown that, even if this matrix fraction representation of W(q) is not coprime, W(q) has a coprime...
In this paper, an iterative algorithm is proposed to solve discrete time algebraic Riccati equations (DARE) with a sign indefinite quadratic term, which arise from linear discrete time H?? control. By constructing two positive semidefinite matrix sequences, we obtain the stabilizing solution of the given DARE. The algorithm has a global convergence property.
In this paper we introduce a new approach to determine the bias in localization algorithms by mixing Taylor series and Jacobian matrices, which results in an easily calculated analytical expression for the bias. To illustrate this approach, we analyze the proposed method in two situations using localization algorithms based on distance measurements. Monte Carlo simulations verify that the proposed...
Location information for sensors in wireless sensor networks (WSNs) is essential to many tasks. In the presence of noise, locations must be estimated and thus the errors are unavoidable. Moreover, the errors can propagate (i.e. increase) as sensors progressively more distant from anchors are localized. Understanding the rules governing error propagation is quite helpful to deploying WSNs and improving...
This paper proposes a systematic approach to the problem of restoring rigidity after loss of an agent, for two-dimensional rigid multi-agent formations based on a particular graph operation, the edge contraction operation. A rigidity maintenance method is proposed, for the cases where an agent is lost in an arbitrary two-dimensional rigid formation, to restore rigidity by transferring all links to...
In this paper we introduce a polynomial method for addressing sensor network localization problems when the inter-sensor measurements are noisy. We compare the results obtained applying this method with the results obtained by other localization methods in the literature. Later in the paper we propose tools from algebraic geometry to aid us solve the problem in a more computationally appealing way.
We propose a connection between the state-space realization and dasiaobserver-likepsila property of a nonlinear feedback system, consisting of an linear time-invariant (LTI) plant and a nonlinear controller by utilizing dasiakernel representationpsila of dynamical systems. This connection is advanced by noticing that the kernel representation shares many properties with and is indeed a generalization...
We propose a coordination algorithm for robotic multi-agent systems with leader-follower structures so that when a leader moves with a constant velocity, its followers can compute the leader's velocity after measuring their distances to the leader for a finite number of times. One feature of the proposed algorithm is that no active communication is needed, and as a result, the algorithm becomes advantageous...
In this paper, we study the giant component, the largest component containing a non-vanishing fraction of nodes, in a wireless multi-hop network where n nodes are randomly and uniformly distributed in [0, 1]d (d = 1, 2) and any two nodes can communicate directly with each other if their Euclidean distance is not larger than the transmission range r. We investigate the probability that the size of...
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