MULTI-MODEL CONTROL OF A SIMULATED PH NEUTRALIZATION PROCESS (2009)
Jari M. Böling, Dale E. Seborg, João P. Hespanha
Abstract: A multi-model PID controller is developed and evaluated in a simulation study for a nonlinear pH neutralization process. The performance and robustness characteristics of the multi-model...
Prabir Barooah, João P. Hespanha
We consider the problem of estimating vector-valued variables from noisy “relative ” measurements. The measurement model can be expressed in terms of a graph. The vertices, or nodes, of the graph...
Abstract A Constant Factor Approximation Algorithm for Event-Based Sampling (2009)
Randy Cogill, Sanjay Lall, João P. Hespanha
We consider a control system in which sensor data is transmitted from the plant to a receiver over a communication channel, and the receiver uses the data to estimate the state of the plant. Using a...
Introduction to Haptics (2009)
Margaret L. Mclaughlin, João P. Hespanha, Gaurav S. Sukhatme
Haptics refers to the modality of touch and associated sensory feedback. Researchers working in the area are concerned with the development, testing, and refinement of tactile and force feedback...
Optimal Estimation from Relative Measurements: Error Scaling (Extended Abstract) (2009)
Prabir Barooah, João P. Hespanha
We consider the problem of estimating a number of vector valued variables from a number of noisy “relative measurements”, i.e., measurement of the difference between certain pairs of these...
Communication Logic Design and Analysis for Networked Control Systems (2009)
Summary. This chapter addresses the control of spatially distributed processes via communication networks with a fixed delay. A distributed architecture is utilized in which multiple local...
M. C. Campi, João P. Hespanha, Maria Pr
hierarchical switching control of stochastic linear systems
The basic principle behind the design of the Internet was to utilize massive redundancy to achieve fault tolerance. With this, one expected to achieve network security, i.e., robustness with respect...
Stability of Delay Impulsive Systems with Application to Networked Control Systems (2008)
Payam Naghshtabrizi, João P. Hespanha, Andrew R. Teel
Abstract — We establish asymptotic and exponential stability theorems for delay impulsive systems by employing Lyapunov functionals with discontinuities. Our conditions have the property that when...
João P. Hespanha, Katia Obraczka (ucsc, Junsoo Lee (usc/ucsb, Abhyudai Singh (ucsb, Yonggang Xu (ucsb, ...
• network traffic under TCP • networked control systems
João P. Hespanha, Stephan Bohacek, Junsoo Lee, Katia Obraczka, Abhyudai Singh, Yonggang Xu, ...
continuous dynamics continuous dynamics Deterministic Hybrid Systems q(t) ∈ Q={1,2,…} ≡ discrete state x(t) ∈ R n ≡ continuous state reset-maps right-continuous by convention guard...
Optimotaxis: A Stochastic Multi-agent Optimization Procedure with Point Measurements ⋆ (2008)
Re R. Mesquita, João P. Hespanha
Abstract. We consider the problem of seeking the maximum of a scalar signal using a swarm of autonomous vehicles equipped with sensors that can take point measurements of the signal. Vehicles are not...
DECENTRALIZED CONTROL OF VEHICULAR PLATOONS: IMPROVING CLOSED LOOP STABILITY BY MISTUNING (2008)
Prabir Barooah, Prashant G. Mehta, João P. Hespanha
We consider decentralized control of a platoon of N identical vehicles moving in a straight line. The control objective is for each vehicle to maintain a constant velocity and inter-vehicular...
A Study of TCP Fairness in High-Speed Networks (2008)
Junsoo Lee, João P. Hespanha, Stephan Bohacek
Abstract — Under the TCP congestion control regime, heterogeneous flows, i.e., flows with different round-trip times (RTTs), that share the same bottleneck link will not attain equal portions of...
ON THE EFFECT OF ASYMMETRIC COMMUNICATION ON DISTRIBUTED TIME SYNCHRONIZATION (2008)
Prabir Barooah, João P. Hespanha, Ananthram Swami
Abstract — Several distributed algorithms have been recently proposed to estimate clock offsets and skews in a network of processors from a set of noisy measurements of the difference between clock...
Switching between stabilizing controllers (2008)
João P. Hespanha, A. Stephen Morse
www.elsevier.com/locate/automatica
LIMITS OF PERFORMANCE IN REFERENCE-TRACKING AND PATH-FOLLOWING FOR NONLINEAR SYSTEMS (2008)
A. Pedro Aguiar, João P. Hespanha, Petar Kokotović
Abstract: We investigate limits of performance in reference-tracking and pathfollowing and highlight an essential difference between them. For a class of nonlinear systems, we show that in...
In optimization, one attempts to find values for parameters that minimize a suitably defined criterion (such as monetary cost, energy consumption, heat generated, etc.) However, in most engineering...
In collaboration with: S. Bohacek (Univ. Delaware), K. Obraczka (UC Santa Cruz) (2008)
João P. Hespanha, J. Lee (postdoc, Uc Santa Barbara
robust routing
Prabir Barooah, João P. Hespanha, Psfrag Replacements
Abstract — We consider the problem of controlling a string of vehicles moving in one dimension so that they all follow a lead vehicle with a constant spacing between successive vehicles. We examine...
Optimotaxis: A Stochastic Multi-agent on Site Optimization Procedure (2008)
Re R. Mesquita, João P. Hespanha
Abstract. We consider the problem of seeking the maximum of a scalar signal using a swarm of autonomous vehicles equipped with sensors that can take point measurements of the signal. Vehicles are not...
The purpose of this course is to provide the students with the basic tools of modern linear systems theory: stability, controllability, observability, realization theory, state feedback, state...
• moment dynamics 4. More examples … Talk outline (2008)
João P. Hespanha, Yonggang Xu, Advertising. Com, Abhyudai Singh (ucsb, Mustafa Khammash (ucsb
• network traffic • networked control systems • biology
LIMITS OF PERFORMANCE IN REFERENCE-TRACKING AND PATH-FOLLOWING FOR NONLINEAR SYSTEMS (2008)
A. Pedro Aguiar, João P. Hespanha, Petar Kokotović
Abstract: We investigate limits of performance in reference-tracking and pathfollowing and highlight an essential difference between them. For a class of nonlinear systems, we show that in...
Tracking Control for Snake Robot Joints (2008)
Aksel A. Transeth, Alexey Pavlov, João P. Hespanha, Kristin Y. Pettersen
Abstract — This paper considers the problem of model based control of the joints of a snake robot without wheels. The potential range of applications for snake robots are numerous, and delicate...
Final exam – 40% Textbook (2008)
The purpose of this course is to provide the students with the basic tools of modern linear systems theory: stability, controllability, observability, realization theory, state feedback, state...
Data Transmission over Networks for Estimation and Control (2008)
Vijay Gupta, Amir F. Dana, Student Member, João P. Hespanha, Richard M. Murray, Babak Hassibi, ...
We consider the problem of controlling a linear time invariant process when the controller is located at a location remote from where the sensor measurements are being generated. The communication...
Robust Filtering for Deterministic Systems with Implicit Outputs Abstract (2008)
A. Pedro Aguiar, João P. Hespanha
This paper addresses the state estimation of a class of continuous-time systems with implicit outputs. We formulate the problem in the deterministic H ∞ filtering setting by computing the value of...
Modeling Communication Networks With Hybrid Systems (2008)
Junsoo Lee, Stephan Bohacek, João P. Hespanha, Senior Member, Katia Obraczka
Abstract—This paper introduces a general hybrid systems framework to model the flow of traffic in communication networks. The proposed models use averaging to continuously approximate discrete...
Chansook Lim, Stephan Bohacek, João P. Hespanha, Katia Obraczka
Abstract. Path disuptions (due to congestion, link failures, which may in turn happen during normal operation or caused by malicious activity) are frequent occurrences on the Internet. Thus, several...
Eric E. S, Petar V. Kokotović, João P. Hespanha
Abstract — Underactuated systems are commonplace and present a challenge in designing tracking controllers. Foremost among these are vehicles, like passenger cars and aircraft. Such systems with n...
Stephan Bohacek, João P. Hespanha, Comp Eng, Junsoo Lee
In this paper we present a general hybrid systems modeling framework to describe the flow of traffic in communication networks. To characterize network behavior, these models use averaging to...
Approximate analytical formulae for stochasticity in a birth-death process 1 (2008)
Abhyudai Singh, João P. Hespanha
Birth-death processes have been widely used for different biological applications, the most common of which is stochastic modeling of population dynamics. A review of these applications can be found...
A New TCP for Persistent Packet Reordering (2008)
Stephan Bohacek, João P. Hespanha, Senior Member, Junsoo Lee, Chansook Lim, Student Member, ...
Abstract—Most standard implementations of TCP perform poorly when packets are reordered. In this paper, we propose a new version of TCP that maintains high throughput when reordering occurs and...
DISTRIBUTED ALGORITHMS AND FUNDAMENTAL LIMITS (2008)
Prabir Barooah, João P. Hespanha
Asensor network is a collection of interconnected nodes that are deployed in a geographic area to perform monitoring tasks. Each node is equipped with sensing and computing capability. Sensor...
Optimization is one of the fundamental tools that every engineer keeps in her “bag-of-tricks. ” Linear optimization (i.e., minimization/maximization linear functions subject to linear constrains)...
3. Analysis tools for SHSs • Lyapunov • moment dynamics (2008)
João P. Hespanha, More Examples, Katia Obraczka (ucsc, Abhyudai Singh (ucsb, Yonggang Xu (ucsb
• network traffic under TCP • networked control systems
Control of Large Vehicular Platoons: Improving Closed Loop Stability by Mistuning (2008)
Prabir Barooah, Prashant G. Mehta, João P. Hespanha
Abstract — We consider decentralized control of a platoon of N identical vehicles moving in a straight line following a single lead vehicle moving at constant velocity. The control objective is for...
Data Transmission over Networks for Estimation and Control (2008)
Vijay Gupta, Student Member, Amir F. Dana, Student Member, João P. Hespanha, Richard M. Murray, ...
We consider the problem of controlling a linear time invariant process when the controller is located at a location remote from where the sensor measurements are being generated. The communication...
HYSTERESIS-BASED SWITCHING CONTROL OF STOCHASTIC LINEAR SYSTEMS (2008)
Maria Pr, João P. Hespanha, M. C. Campi
stochastic hybrid systems; uncertain systems. We study hysteresis-based switching control for a class of discrete-time stochastic linear systems. We take as given a family of candidate controllers...
A New TCP for Persistent Packet Reordering (2008)
Stephan Bohacek, João P. Hespanha, Junsoo Lee, Chansook Lim, Katia Obraczka
Abstract — Most standard implementations of TCP perform poorly when packets are reordered. In this paper, we propose a new version of TCP that maintains high throughput when reordering occurs and...
Modeling Communication Networks with Hybrid Systems (2008)
Junsoo Lee, Stephan Bohacek, João P. Hespanha, Senior Member, Katia Obraczka
Abstract — This paper introduces a general hybrid systems framework to model the flow of traffic in communication networks. The proposed models use averaging to continuously approximate discrete...
Modeling Communication Networks with Hybrid Systems: Extended Version (2008)
Junsoo Lee, Bohacek Stephan, João P. Hespanha, Katia Obraczka
Abstract — This paper introduces a general hybrid systems framework to model the flow of traffic in communication networks. The proposed models use averaging to continuously approximate discrete...
Stephan Bohacek, João P. Hespanha, Comp Eng, Junsoo Lee
In this paper we present a general hybrid systems modeling framework to describe the flow of traffic in communication networks. To characterize network behavior, these models use averaging to...
A survey of recent results in networked control systems (2007)
João P. Hespanha, Payam Naghshtabrizi, Yonggang Xu, Psfrag Replacements
Networked Control Systems (NCSs) are spatially distributed systems for which the communication between sensors, actuators, and controllers is supported by a shared communication network. In this...
On Discrete-time Pursuit-evasion Games with Sensing Limitations (2007)
Francesco Bullo, João P. Hespanha
We address discrete-time pursuit-evasion games in the plane where every player has identical sensing and motion ranges restricted to closed discs of given sensing and stepping radii. A single evader...
Cooperative graph-based model predictive search (2007)
James R. Riehl, Gaemus E. Collins, João P. Hespanha
Abstract — We present a receding-horizon cooperative search algorithm that jointly optimizes routes and sensor orientations for a team of autonomous agents searching for a mobile target. By...
Disclaimer: This is a draft and probably contains several typos. Comments and information about typos are welcome. Please contact the author at (hespanha@ ece.ucsb.edu). c ○ Copyright to João...
Modeling and analysis of stochastic hybrid systems (2007)
The author describes a model for Stochastic Hybrid Systems (SHSs) where transitions between discrete modes are triggered by stochastic events. The rate at which these transitions occur is allowed to...
Sensing limitations in the Lion and Man problem (2007)
Shaunak D. Bopardikar, Francesco Bullo, João P. Hespanha, Man Problem
in a bounded, convex, planar environment in which both players have identical sensing ranges, restricted to closed discs about their current locations. The evader is randomly located inside the...
Exponential stability of impulsive systems with application to uncertain sampled-data systems (2007)
Undergraduate Lecture Notes on Nonlinear Control (2007)
Disclaimer: This is a draft and probably contains several typos.
Contents 1 Computer-Controlled Systems 3 (2007)
Disclaimer: This is a draft and probably contains several typos.
Sensing limitations in the Lion and Man problem (2007)
Shaunak D. Bopardikar, Francesco Bullo, João P. Hespanha, Man Problem
in a bounded, convex, planar environment in which both players have identical sensing ranges, restricted to closed discs about their current locations. The evader is randomly located inside the...
Anticipative and Non-anticipative Controller Design for Network Control Systems (2006)
Payam Naghshtabrizi, João P. Hespanha
Summary. We propose a numerical procedure to design a linear output-feedback controller for a remote linear plant in which the loop is closed through a network. The controller stabilizes the plant in...
Multi-path Routing for Networked Control Systems (2006)
1 Estimation over a faulty network Consider the problem of estimating the state of a linear systems x(k + 1) = Ax(k) + Bw(k), ∀k ≥ 0, at a remote location, based on state measurements transmitted...
Graph effective resistances and distributed control: Spectral properties and applications (2006)
Prabir Barooah, João P. Hespanha
We introduce the concept of matrix-valued effective resistance for undirected matrix-weighted graphs. These effective resistances are defined to be the square blocks that appear in the diagonal of...
Distributed optimal estimation from relative measurements (2006)
Prabir Barooah, João P. Hespanha
Abstract. We consider the problem of estimating vector-valued variables from noisy “relative ” measurements. The measurement model can be expressed in terms of a graph, whose nodes correspond to...
Bhaskar Dasgupta, João P. Hespanha, James Riehl, Eduardo Sontag
In this paper we investigate the problem of searching for a hidden target in a bounded region of the plane by an autonomous robot which is only able to use local sensory information. The problem is...
Modeling data communication networks using hybrid systems: Extended version (2006)
Junsoo Lee, Bohacek Stephan, João P. Hespanha, Katia Obraczka
Abstract — This paper introduces a general hybrid systems framework to model the flow of traffic in communication networks. The proposed models use averaging to continuously approximate discrete...
Model Checking of Hybrid Systems: From Reachability towards Stability (2006)
Podelski, Andreas, Wagner, Silke, Hespanha, João P., Tiwari, Ashish
We call a hybrid system {\em stable} if every trajectory inevitably ends up in a given region. Our notion of stability deviates from classical definitions in control theory. In this paper, we present...
Stochastic impulsive systems driven by renewal processes (2005)
João P. Hespanha, Andrew R. Teel
Abstract — Stochastic impulsive systems are defined by a diffusion process with jumps triggered by a renewal process, i.e., the intervals between jumps are independent and identically distributed....
Stabilization of nonlinear systems with limited information feedback (2005)
Daniel Liberzon, João P. Hespanha
Abstract—This note is concerned with the problem of stabilizing a nonlinear continuous-time system by using sampled encoded measurements of the state. We demonstrate that global asymptotic...
Hierarchical max-flow routing (2005)
Chansook Lim, João P. Hespanha
Abstract — This paper describes a technique to reduce the computational complexity of max-flow routing, based on a hierarchical decomposition of the network. The computational complexity of this...
Estimation under uncontrolled and controlled communications in networked control systems (2005)
Abstract — An LTI estimation framework is proposed for networked control systems (NCS), in which local Kalman filter estimates are sent to the remote estimator. Both controlled and uncontrolled...
Path-following for non-minimum phase systems removes performance limitations (2005)
A. Pedro Aguiar, João P. Hespanha, Petar V. Kokotović
Abstract — We highlight an essential difference between path-following and reference-tracking for non-minimum phase systems. It is well-known that in the reference-tracking, for non-minimum phase...
A. Pedro Aguiar, João P. Hespanha, Senior Member
Abstract — We address the problem of position trajectorytracking and path-following control design for underactuated autonomous vehicles in the presence of possibly large modeling parametric...
On input-to-state stability of impulsive systems (2005)
Abstract — This paper introduces appropriate concepts of input-to-state stability (ISS) and integral-ISS for systems with impulsive effects. We provide a set of Lyapunov-based sufficient conditions...
Hierarchical max-flow routing (2005)
Chansook Lim, João P. Hespanha
Abstract — This paper describes a technique to reduce the computational complexity of max-flow routing, based on a hierarchical decomposition of the network. The computational complexity of this...
On input-to-state stability of impulsive systems (2005)
Abstract — This paper introduces appropriate concepts of input-to-state stability (ISS) and integral-ISS to systems with impulsive effects. We provide a set of Lyapunov-based sufficient conditions...
Stochastic impulsive systems driven by renewal processes (2005)
João P. Hespanha, Andrew R. Teel
Abstract — Stochastic impulsive systems are defined by a diffusion process with jumps triggered by a renewal process, i.e., the intervals between jumps are independent and identically distributed....
On input-to-state stability of impulsive systems (2005)
Abstract — This paper introduces appropriate concepts of input-to-state stability (ISS) and integral-ISS for systems with impulsive effects. We provide a set of Lyapunov-based sufficient conditions...
Nonlinear norm-observability notions and stability of switched systems (2005)
João P. Hespanha, Senior Member, Daniel Liberzon, Senior Member, David Angeli, Eduardo D. Sontag
Abstract—This paper proposes several definitions of “norm-observability” for nonlinear systems and explores relationships among them. These observability properties involve the existence of a...
Stabilization of nonlinear systems with limited information feedback (2005)
Daniel Liberzon, João P. Hespanha
Abstract—This note is concerned with the problem of stabilizing a nonlinear continuous-time system by using sampled encoded measurements of the state. We demonstrate that global asymptotic...
On input-to-state stability of impulsive systems (2005)
Abstract — This paper introduces appropriate concepts of input-to-state stability (ISS) and integral-ISS for systems with impulsive effects. We provide a set of Lyapunov-based sufficient conditions...
Nonlinear norm-observability notions and stability of switched systems (2005)
João P. Hespanha, Senior Member, Daniel Liberzon, Senior Member, David Angeli, Eduardo D. Sontag
Abstract—This paper proposes several definitions of “norm-observability” for nonlinear systems and explores relationships among them. These observability properties involve the existence of a...
Aggregation-based approaches to honey-pot searching with local sensory information (2004)
Bhaskar Dasgupta, João P. Hespanha, Eduardo Sontag
Abstract — We investigate the problem of searching for a hidden target in a bounded region by an autonomous agent that is only able to use limited local sensory information. We propose an...
A model for stochastic hybrid systems with application to communication networks (2004)
Abstract. We propose a model for Stochastic Hybrid Systems (SHSs) where transitions between discrete modes are triggered by stochastic events much like transitions between states of a continuoustime...
Cautious hierarchical switching control of stochastic linear systems”, in Int (2004)
M. C. Campi, João P. Hespanha, Maria Prandini
Standard switching control methods are based on the certainty equivalence philosophy in that, at each switching time, the supervisor selects the candidate controller that is better tuned to the...
Optimal Communication Logics for Networked Control Systems (2004)
Abstract — This paper addresses the control of spatially distributed processes over a network that imposes bandwidth constraints and communication delays. Optimal communication policies are derived...
Stochastic Hybrid Systems: Application to Communication Networks (2004)
Abstract. We propose a model for Stochastic Hybrid Systems (SHSs) where transitions between discrete modes are triggered by stochastic events much like transitions between states of a continuous-time...
Communication logics for networked control systems (2004)
Abstract — This paper addresses the control of spatially distributed processes. We utilize a distributed architecture in which multiple local controllers coordinate their efforts through a data...
Path-following or reference-tracking? An answer relaxing the limits to performance (2004)
A. Pedro Aguiar, Dragan B. Dačić, João P. Hespanha, Petar Kokotović
In path-following the control objective is to force the output to follow a geometric path without a timing law assigned to it. We highlight a fundamental difference between the path-following and the...
Stochastic Hybrid Systems: Application to Communication Networks (2004)
Abstract. We propose a model for Stochastic Hybrid Systems (SHSs) where transitions between discrete modes are triggered by stochastic events much like transitions between states of a continuous-time...
Analysis of Emerson’s Multiple Model Interpolation Estimation Algorithms: (2004)
João P. Hespanha, Dale E. Seborg
We extend to Multiple-Input/Multiple-Output (MIMO) processes the previous analysis of Emerson’s Moving Multiple Model Interpolation (MMMI) algorithm for parameter estimation and compare it with...
Aggregation-based approaches to honey-pot searching with local sensory information (2004)
Bhaskar Dasgupta, João P. Hespanha, Eduardo Sontag
We investigate the problem of searching for a hidden target in a bounded region of the plane, by an autonomous robot which is only able to use limited local sensory information. We propose an...
An efficient Matlab algorithm for graph partitioning,” tech (2004)
This report describes a graph partitioning algorithm based on spectral factorization that can be implemented very efficiently with just a hand full of MATLAB commands. The algorithm is closely...
Problem Twenty Eight L2-Induced Gains of Switched Linear Systems (2003)
and Control Theory we proposed the problem of computing inputoutput gains of switched linear systems. Recent developments provided new insights into this problem leading to new questions. 28.1...
Root-mean-square gains of switched linear systems (2003)
In this paper we compute the root-mean-square (RMS) gain of a switched linear system when the interval between consecutive switchings is large. The algorithm proposed is based on the fact that a...
Optimal estimation from relative measurements: Electrical analogy and error bounds (2003)
Prabir Barooah, João P. Hespanha
We examine the problem of estimating vector-valued variables from noisy measurements of the difference between certain pairs of them. This problem, which is naturally posed in terms of a measure-ment...
Root-mean-square gains of switched linear systems (2003)
Michael Margaliot, João P. Hespanha
Abstract — We consider the problem of computing the rootmean-square (RMS) gain of switched linear systems. We develop a new approach which is based on an attempt to characterize the “worst-case...
Optimal estimation from relative measurements: Electrical analogy and error bounds (2003)
Prabir Barooah, Student Member, João P. Hespanha
Abstract — We examine the problem of estimating vectorvalued variables from noisy measurements of the difference between certain pairs of them. This problem, which is naturally posed in terms of a...
Minimum-energy state estimation for systems with perspective outputs (2003)
A. Pedro Aguiar, João P. Hespanha, Senior Member
Abstract — This paper addresses the state estimation of systems with perspective outputs. We derive a minimum-energy estimator which produces an estimate of the state that is “most compatible”...
Root-mean-square gains of switched linear systems (2003)
João P. Hespanha, Senior Member
Abstract — In this paper we compute the root-mean-square (RMS) gain of a switched linear system when the interval between consecutive switchings is large. The algorithm proposed is based on the...
TCP-PR: TCP for persistent packet reordering (2003)
Stephan Bohacek, João P. Hespanha, Junsoo Lee, Chansook Lim, Katia Obraczka
Most standard implementations of TCP perform poorly when packets are reordered. In this paper, we propose a new version of TCP that maintains high throughput when reordering occurs and yet, when...
Papers referenced specifically in this talk: [1] S. Bohacek, J. Hespanha, J. Lee, K. Obraczka. Analysis of a TCP hybrid model. In Proc. of
Hybrid Modeling of Communication Networks Using Modelica (2002)
Daniel Färnqvist, Katrin Str, Karl H. Johansson, João P. Hespanha
The objective with research on control of networks is often to improve traffic throughput and to better accommodate different service demands. Communication networks experience major problems due to...
Saddle policies for secure routing in communication networks (2002)
Stephan Bohacek, João P. Hespanha, Katia Obraczka
In this paper we formalize routing in communication networks as a game between the designer of the routing algorithm and an attacker that attempts to intercept packets. By computing saddle-point...
Optimal pursuit under partial information (2002)
João P. Hespanha, Maria Prandini
with partial information; dynamic programming; value iteration; greedy policies. In this paper we address the control of a group of agents in the pursuit of one or several evaders that are moving in...
Nonlinear observability and an invariance principle for switched systems (2002)
This paper proposes several definitions of observability for nonlinear systems and explores relationships between them. These observability properties involve the existence of a bound on the norm of...
State estimation and control for systems with perspective outputs (2002)
In this paper we consider the problem of estimating the state of a system with perspective outputs. We formulate the problem in a deterministic setting by searching for the value of the state that is...
Nonlinear observability and an invariance principle for switched systems (2002)
This paper proposes several definitions of observability for nonlinear systems and explores relationships between them. These observability properties involve the existence of a bound on the norm of...
Saddle policies for secure routing in communication networks (2002)
Stephan Bohacek, João P. Hespanha, Katia Obraczka
In this paper we prove that the off-line policies proposed in a previous paper [1] for secure routing in communication networks are actually saddle-point solutions and therefore not overly...
Enhancing security via stochastic routing (2002)
Stephan Bohacek, João P. Hespanha, Katia Obraczka, Junsoo Lee, Chansook Lim
Abstract—Shortest path routing leaves connections at risk of interception and eavesdropping since the path over which data packets travel is fairly predictable and easy to determine. To improve...
Saddle policies for secure routing in communication networks (2002)
Stephan Bohacek, João P. Hespanha, Katia Obraczka
In this paper we formalize routing in communication networks as a game between the designer of the routing algorithm and an attacker that attempts to intercept packets. By computing saddle-point...
Nonlinear Observability and an Invariance Principle for Switched Systems (2002)
Joao Hespanha Dept, João P. Hespanha
This paper proposes several definitions of observability for nonlinear systems and explores relationships between them. These observability properties involve the existence of a bound on the norm of...
Nonlinear observability and an invariance principle for switched systems (2002)
This paper proposes several definitions of observability for nonlinear systems and explores relationships between them. These observability properties involve the existence of a bound on the norm of...
Stephan Bohacek, João P. Hespanha, Junsoo Lee, Chansook Lim, Katia Obraczka
Most standard implementations of TCP perform poorly when packets are reordered. In this paper, we propose a new version of TCP that maintains high throughput when reordering occurs and yet, when...
Preliminary results in routing games (2001)
João P. Hespanha, Stephan Bohacek
this paper we determine routing polices for a data In network that are robust with respect to transmission of packet interception by an adversary. This attempts is formulated as a zero-sum game...
Nash equilibria in partial-information games on Markov chains (2001)
We consider a two-player partial-information game on a Markov chain, where each player attempts to minimize its own cost over a finite time horizon. We show that this game has always a Nash...
Analysis of a TCP hybrid model (2001)
Stephan Bohacek, João P. Hespanha, Junsoo Lee, Katia Obraczka
In this paper we use hybrid systems to model and analyze the transient and steady-state behavior of multiple TCP flows that share a single common bottleneck link. The main contributions of this paper...
A Hybrid Systems Framework for TCP Congestion Control (2001)
Stephan Bohacek, João P. Hespanha, Junsoo Lee, Katia Obraczka
Abstract — In this paper we make use of hybrid systems to model the transient and steady-state behavior of multiple TCP flows that share a single common bottleneck link. The contributions of our...
Analysis of a TCP hybrid model (2001)
Stephan Bohacek, João P. Hespanha, Junsoo Lee, Katia Obraczka
In this paper we use hybrid systems to model and analyze the transient and steady-state behavior of multiple TCP flows that share a single common bottleneck link. The main contributions of this paper...
Haptic collaboration over the internet (2000)
João P. Hespanha, Margaret Mclaughlin, Gaurav S. Sukhatme, Minoo Akbarian, Rajiv Garg, Weirong Zhu
We address the real-time collection and simultaneous broadcast of haptic information to multiple haptic session participants, so that collaborative exploration of objects is possible, even when users...
Switching Between Stabilizing Controllers (2000)
João P. Hespanha, Jo~ao P. Hespanha, A. Stephen Morse
This paper deals with the problem of switching between several linear time-invariant (LTI) controllers|all of them capable of stabilizing a specic LTI process|in such a way that the stability of the...
Probabilistic Pursuit-Evasion Games: A One-Step Nash Approach (2000)
João P. Hespanha, Jo~ao P. Hespanha, Maria Prandini, Shankar Sastry
This paper addresses the control of a team of autonomous agents pursuing a smart evader in a nonaccurately mapped terrain. By describing this problem as a partial information Markov game, we are able...
Deception in Non-Cooperative Games with Partial Information (2000)
João P. Hespanha, Yusuf S. Ateskan, Huseyin H. Kizilocak, Jo~ao P. Hespanha
In this paper we explore how deception can be used by rational players in the context of non-cooperative stochastic games with partial information. We show that, when one of the players can...
Probabilistic Pursuit-Evasion Games: A One-Step Nash Approach (2000)
João P. Hespanha, Jo~ao P. Hespanha, Maria Prandini, Shankar Sastry
This paper addresses the control of a team of autonomous agents pursuing a smart evader in a non-accurately mapped terrain. By describing the problem as a partial information Markov game, we are able...
Towards the supervisory control of uncertain nonholonomic systems (1999)
João P. Hespanha, Daniel Liberzon, A. Stephen Morse
Control systems with nonholonomic motion constraints have been extensively studied in the recent years, particularly in the context of robotics. Robotic manipulators, especially mobile ones, are...
Multiple-agent probabilistic pursuit-evasion games (1999)
This paper addresses the control of a team of autonomous agents pursuing a smart evader in a non-accurately mapped terrain. By describing the problem as a partial information Markov game, we are able...
Stability of switched systems with average dwell-time (1999)
It is shown that switching among stable linear systems results in a stable system provided that switching is “slow-on-the-average. ” In particular, it is proved that exponential stability is...
Stability of switched systems: a Lie-algebraic condition (1999)
Daniel Liberzon, João P. Hespanha, A. Stephen Morse
We present a sufficient condition for asymptotic stability of a switched linear system in terms of the Lie algebra generated by the individual matrices. Namely, if this Lie algebra is solvable, then...
Multiple-agent probabilistic pursuit-evasion games (1999)
In this paper we develop a probabilistic framework for pursuit-evasion games. We propose a “greedy ” policy to control a swarm of autonomous agents in the pursuit of one or several evaders. At...
Logic-based switching control of a nonholonomic system with parametric modeling uncertainty (1999)
João P. Hespanha, Daniel Liberzon, A. Stephen Morse
This paper is concerned with control of nonholonomic systems in the presence of parametric modeling uncertainty. The specific problem considered is that of parking a wheeled mobile robot of unicycle...
Multiple-agent probabilistic pursuit-evasion games (1999)
João P. Hespanha, A One-step, Maria Prandini
This paper addresses the control of a team of autonomous agents pursuing a smart evader in a non-accurately mapped terrain. By describing the problem as a partial information Markov game, we are able...
Stability of Switched Systems with Average Dwell-Time (1999)
João P. Hespanha, Jo~ao P. Hespanha, A. Stephen Morse
It is shown that switching among stable linear systems results in a stable system provided that switching is \slow-on-the-average." In particular, it is proved that exponential stability is...
Stability of Switched Systems with Average Dwell-Time (1999)
João P. Hespanha, Jo~ao P. Hespanha, A. Stephen Morse
It is shown that switching among stable linear systems results in a stable system provided that switching is "slow-on-the-average." In particular, it is proved that exponential stability is...
Multiple-Agent Probabilistic Pursuit-Evasion Games (1999)
João P. Hespanha, Jo~ao P. Hespanha, Hyoun Jin Kim, Shankar Sastry
In this paper we develop a probabilistic framework for pursuit-evasion games. We propose a "greedy" policy to control a swarm of autonomous agents in the pursuit of one or several evaders....
Towards the Supervisory Control of Uncertain Nonholonomic Systems (1999)
João P. Hespanha, Jo~ao P. Hespanha, Daniel Liberzon, A. Stephen Morse
this paper is to demonstrate that a promising alternative to conventional adaptive control for nonholonomic systems is provided by the supervisory control techniques which have been developed for...
Supervisory Control Of Integral-Input-To-State Stabilizing Controllers (1999)
João P. Hespanha, Jo~ao P. Hespanha, A. Stephen Morse
A high-level supervisor, employing switching and logic, is proposed to orchestrate the switching between a family of candidate controllers into feedback with an imprecisely modeled process so as to...
Towards the Supervisory Control of Uncertain Nonholonomic Systems (1999)
João P. Hespanha, Jo~ao P. Hespanha, Daniel Liberzon, A. Stephen Morse
This paper is concerned with control of nonholonomic systems in the presence of parametric modeling uncertainties. The specific problem considered is that of parking a wheeled mobile robot of...
Multiple-Agent Probabilistic Pursuit-Evasion Games (1999)
João P. Hespanha, Jo~ao P. Hespanha, Hyoun Jin Kim, Shankar Sastry
In this paper we develop a probabilistic framework for pursuit-evasion games. We propose a "greedy" policy to control a swarm of autonomous agents in the pursuit of one or several evaders....
Towards the Supervisory Control of Uncertain Nonholonomic Systems (1999)
João P. Hespanha, Jo~ao P. Hespanha, Daniel Liberzon, A. Stephen Morse
this paper is to demonstrate that a promising alternative to conventional adaptive control for nonholonomic systems is provided by the supervisory control techniques which have been developed for...
Supervisory Control of Integral-Input-to-State Stabilizing Controllers (1999)
João P. Hespanha, A. Stephen Morse
A high-level supervisor, employing switching and logic, is proposed to orchestrate the switching between a family of candidate controllers into feedback with an imprecisely modeled process so as to...
Abstract Logic-Based Switching Algorithms in Control (1998)
João P. Hespanha, Maria José, António Hespanha
This thesis deals with the use of logic-based switching in the control of imprecisely modeled nonlinear systems. Each control system considered consists of a continuous-time dynamical process to be...
Supervisory Control of Families of Noise Suppressing Controllers (1998)
Shogo Fujii, João P. Hespanha, Jo~ao P. Hespanha, A. Stephen Morse
This paper describes a high-level "supervisor" capable of switching into feedback with a single-input/singleoutput (SISO), linear time-invariant (LTI) process a sequence of linear...
Scale-Independent Hysteresis Switching (1998)
João P. Hespanha, Jo~ao P. Hespanha, A. Stephen Morse
. This paper introduces a new switching logic inspired by the hysteresis switching logic considered in [7, 11]. The new logic also uses hysteresis to prevent chatter, but unlike its predecessor in...
Eigenfaces vs. Fisherfaces: Recognition Using Class Specific Linear Projection (1996)
Peter N. Belhumeur, João P. Hespanha, Jo~ao P. Hespanha, David J. Kriegman
. We develop a face recognition algorithm which is insensitive to gross variation in lighting direction and facial expression. Taking a pattern classification approach, we consider each pixel in an...
Stabilization of Nonholonomic Integrators via Logic-Based Switching (1996)
João P. Hespanha, Jo~ao P. Hespanha, A. Stephen Morse
This paper explains how to stabilize a "nonholonomic integrator" using a hybrid control law employing switching and logic. Results concerning asymptotic stability and exponential...
Logic-Based Switching Control of a Nonholonomic System With Parametric Modeling Uncertainty
João P. Hespanha, Jo~ao P. Hespanha, Daniel Liberzon, A. Stephen Morse
This paper is concerned with control of nonholonomic systems in the presence of parametric modeling uncertainty. The specific problem considered is that of parking a wheeled mobile robot of unicycle...
Stability of switched systems: a Lie-algebraic condition
Daniel Liberzon, João P. Hespanha, Jo~ao P. Hespanha, A. Stephen Morse
We present a sufficient condition for asymptotic stability of a switched linear system in terms of the Lie algebra generated by the individual matrices. Namely, if this Lie algebra is solvable, then...
Logic-Based Switching Control of a Nonholonomic System With Parametric Modeling Uncertainty
João P. Hespanha, Jo~ao P. Hespanha, Daniel Liberzon, A. Stephen Morse
This paper is concerned with control of nonholonomic systems in the presence of parametric modeling uncertainties. The specific problem considered is that of parking a wheeled mobile robot of...