@book {65, title = {Hybrid Dynamical Systems: Modeling, Stability, and Robustness}, year = {2012}, publisher = {Princeton University Press}, organization = {Princeton University Press}, address = {New Jersey}, keywords = {hybrid systems}, doi = {http://www.u.arizona.edu/~sricardo/index.php?n=Main.Books}, author = {R. Goebel and R. G. Sanfelice and A. R. Teel} } @mastersthesis {20, title = {Robust Hybrid Control Systems}, year = {2007}, school = {University of California, Santa Barbara}, type = {phd}, abstract = {This thesis deals with systems exhibiting both continuous and discrete dynamics, perhaps due to intrinsic behavior or to the interaction of continuous-time and discrete-time dynamics emerging from its components and/or their interconnection. Such systems are called hybrid systems and permit the modeling of a wide range of engineering systems and scientific processes. In this thesis, hybrid systems are treated as dynamical systems: the interplay between continuous and discrete behavior is captured in a mathematical model given by differential equations/inclusions and difference equations/inclusions, which we simply call hybrid equations. We develop tools for systematic analysis and robust design of hybrid systems, with an emphasis on systems that involve control algorithms, that is, hybrid control systems. To this effect, we identify mild conditions that hybrid equations need to satisfy so that their behavior captures the effect of arbitrarily small perturbations. This leads to novel concepts of generalized solutions that impart a deep understanding not only on the robustness properties of hybrid systems but also on the structural properties of their solutions. In turn, these conditions enable us to generate various tools for hybrid systems that resemble those in the stability theory of classical dynamical systems. These include general versions of Lyapunov and Krasovskii stability theorems, and LaSalle-type invariance principles. Additionally, we establish results on robustness of stability of hybrid control for general nonlinear systems. We also present a novel mathematical framework for numerical simulation of hybrid systems and its asymptotic stability properties. The contributions of this thesis are not limited to the theory of hybrid systems as they have implications in the analysis and design of practically relevant engineering control systems. In this regard, we develop general control strategies for dynamical systems that are applicable, for example, to autonomous vehicles, multi-link pendulums, and juggling systems.}, keywords = {hybrid systems}, url = {https://hybrid.soe.ucsc.edu/files/preprints/20.pdf}, author = {R. G. Sanfelice} } @mastersthesis {2, title = {Novel current control for {AC} motors}, year = {2001}, school = {Universidad Nacional de Mar del Plata}, abstract = {

In this project, we introduce a new current control method to reduce the electromagnetic torque ripple in AC induction motors. Our control strategy features hysteresis switching to accomplish the disturbance rejection task. We compare our results with the methods currently available in the literature both by compuer simulations and experiments. The testbed consists of an 1HP AC induction motor and electronic hardware ADMC401-ADVKIT from Analog Devices where the control algorithm is implemented. Our results show that out control strategy reduces the electromagnetic ripple up to 50\% compared to currently existing methods.

}, keywords = {hybrid systems}, url = {https://hybrid.soe.ucsc.edu/files/preprints/2.pdf}, author = {R. G. Sanfelice} } @inbook {105, title = {Analysis and Design of Cyber-Physical Systems: A Hybrid Control Systems Approach}, booktitle = {Cyber Physical Systems: From Theory to Practice}, year = {2015}, pages = {3-31}, publisher = {CRC Press}, organization = {CRC Press}, keywords = {hybrid systems}, doi = {10.1201/b19290-3}, author = {R. G. Sanfelice} } @inbook {103, title = {Feedback Control of Hybrid Dynamical Systems}, booktitle = {Encyclopedia of Systems and Control}, series = {NULL}, year = {2015}, publisher = {Springer}, organization = {Springer}, keywords = {hybrid systems}, author = {R. G. Sanfelice} } @inbook {77, title = {Control of Hybrid Dynamical Systems: An Overview of Recent Advances}, booktitle = {Hybrid Systems with Constraints}, series = {NULL}, year = {2013}, month = {April}, pages = {146-177}, publisher = {Wiley}, organization = {Wiley}, keywords = {hybrid systems}, doi = {http://eu.wiley.com/WileyCDA/WileyTitle/productCd-1848215274.html}, author = {R. G. Sanfelice}, editor = {J. Daafouz and S. Tarbouriech and M. Sigalotti} } @inbook {36, title = {Hybrid Control Systems}, booktitle = {Encyclopedia of Complexity and Systems Science}, series = {NULL}, year = {2009}, publisher = {Springer}, organization = {Springer}, abstract = {This article will present a general framework for modeling hybrid control systems and studying their dynamical properties. It will put forth basic tools for studying asymptotic stability properties of hybrid systems. Then, particular aspects of hybrid control will be described, as well as approaches to control objectives that can be successfully achieved via hybrid control even if they are not solvable with classical methods.}, keywords = {hybrid systems}, author = {A. R. Teel and R. G. Sanfelice and R. Goebel} } @inbook {21, title = {Hybrid systems: limit sets and zero dynamics with a view toward output regulation}, booktitle = {Analysis and Design of Nonlinear Control Systems}, year = {2008}, pages = {241-261}, publisher = {Springer-Verlag}, organization = {Springer-Verlag}, chapter = {Hybrid systems: limit sets and zero dynamics with a view toward output regulation}, abstract = {

We present results on omega-limit sets and minimum phase zero dynamics for hybrid dynamical systems. Moreover, we give pointers to how these results may be useful in the future for solving the output regulation problem for hybrid systems. We highlight the main attributes of omega-limit sets and we show, under mild conditions, that they are asymptotically stable. We define a minimum phase notion in terms of omega-limit sets and establish an equivalent Lyapunov characterization. Then we study the feedback stabilization problem for a class of minimum phase, relative degree one hybrid systems. Finally, we discuss output regulation for this class of hybrid systems. We illustrate the concepts with examples throughout the paper.

}, keywords = {hybrid systems}, doi = {http://www.springer.com/west/home/generic/search/results?http://www.springerlink.com/content/r00r175353435104/fulltext.pdf}, url = {https://hybrid.soe.ucsc.edu/files/preprints/21.pdf}, author = {C. Cai and R. Goebel and R. G. Sanfelice and A. R. Teel}, editor = {A. Astolfi and L. Marconi and A. Astolfi and L. Marconi} } @article {112, title = {Robust Asymptotic Stability of Desynchronization in Impulse-Coupled Oscillators}, journal = {IEEE Transactions on Control of Network Systems}, volume = {3}, year = {2016}, month = {June}, pages = {127-136}, abstract = {

The property of desynchronization in an all-to-all network of homogeneous impulse-coupled oscillators is studied. Each impulse-coupled oscillator is modeled as a hybrid system with a single timer state that self-resets to zero when it reaches a threshold, at which event all other impulse-coupled oscillators adjust their timers following a common reset law. In this setting, desynchronization is considered as each impulse-coupled oscillator{\textquoteright}s timer having equal separation between successive resets. We show that for the considered model, desynchronization is an asymptotically stable property. For this purpose, we recast desynchronization as a set stabilization problem and employ Lyapunov stability tools for hybrid systems. Furthermore, several perturbations are considered showing that desynchronization is a robust property. Perturbations on the continuous and discrete dynamics are considered. Numerical results are presented to illustrate the main contributions.

}, keywords = {hybrid systems}, author = {S. Phillips and R. G. Sanfelice} } @article {111, title = {A Finite-time Convergent Observer with Robustness to Piecewise-constant Measurement Noise}, journal = {Automatica}, volume = {57}, year = {2015}, month = {July}, pages = {222-230}, keywords = {hybrid systems, observers}, author = {Y. Li and R. G. Sanfelice} } @article {110, title = {Robust Global Stabilization of the {DC-DC} Boost Converter via Hybrid Control}, journal = {IEEE Transactions on Circuits and Systems I}, volume = {62}, year = {2015}, month = {April}, pages = {1052-1061}, keywords = {hybrid systems, power systems}, author = {T. A. F. Theunisse and J. Chai and R. G. Sanfelice and W. P. M. H. Heemels} } @article {100, title = {Input-Output Triggered Control using Lp Stability over Finite Horizons}, journal = {International Journal of Robust and Nonlinear Control}, year = {2015}, month = {June}, pages = {2299--2327 }, keywords = {hybrid systems}, doi = {10.1002/rnc.3203}, author = {D. Tolic and R. G. Sanfelice and R. Fierro} } @article {96, title = {Input-Output-to-State Stability Tools for Hybrid Systems and Their Interconnections}, journal = {IEEE Transactions on Automatic Control}, volume = {59}, number = {5}, year = {2014}, month = {May}, pages = {1360-1366}, keywords = {hybrid systems}, author = {R. G. Sanfelice} } @article {89, title = {Dynamical Properties of a Two-gene Network with Hysteresis}, journal = {Special Issue on Hybrid Systems and Biology, Elsevier Information and Computation}, volume = {236}, year = {2014}, month = {August}, pages = {102--121}, chapter = {102}, keywords = {hybrid systems}, author = {Q. Shu and R. G. Sanfelice} } @article {88, title = {On Minimum-time Paths of Bounded Curvature with Position-dependent Constraints}, journal = {Automatica}, volume = {50}, number = {2}, year = {2014}, month = {February}, pages = {537{\textendash}546}, keywords = {hybrid systems}, doi = {http://www.sciencedirect.com/science/article/pii/S0005109813005335}, author = {R. G. Sanfelice and S. Z. Yong and E. Frazzoli} } @article {75, title = {On the existence of control {L}yapunov functions and state-feedback laws for hybrid systems}, journal = {IEEE Transactions on Automatic Control}, volume = {58}, number = {12}, year = {2013}, month = {December}, pages = {3242{\textendash}3248}, keywords = {hybrid systems}, url = {https://hybrid.soe.ucsc.edu/files/preprints/75.pdf}, author = {R. G. Sanfelice} } @article {70, title = {Robust Supervisory Control for Uniting Two Output-Feedback Hybrid Controllers with Different Objectives}, journal = {Automatica}, volume = {49}, number = {7}, year = {2013}, month = {July}, pages = {1958{\textendash}1969}, keywords = {hybrid systems}, doi = {http://www.sciencedirect.com/science/article/pii/S0005109813001787}, url = {https://hybrid.soe.ucsc.edu/files/preprints/70.pdf}, author = {R. G. Sanfelice and C. Prieur} } @article {69, title = {Passivity-based Control for Hybrid Systems with Applications to Mechanical Systems Exhibiting Impacts}, journal = {Automatica}, volume = {49}, number = {5}, year = {2013}, month = {May}, pages = {1104{\textendash}1116}, keywords = {hybrid systems}, url = {https://hybrid.soe.ucsc.edu/files/preprints/69.pdf}, author = {R. Naldi and R. G. Sanfelice} } @article {67, title = {An Embedding Approach for the Design of State-Feedback Tracking Controllers for References with Jumps}, journal = {International Journal of Robust and Nonlinear Control}, volume = {24}, number = {11}, year = {2013}, pages = {1585{\textendash}1608}, abstract = {

We study the problem of designing state-feedback controllers to track time-varying state trajectories that may exhibit jumps. Both plants and controllers considered are modeled as hybrid dynamical systems, which are systems with both continuous and discrete dynamics, given in terms of a flow set, a flow map, a jump set, and a jump map. Using recently developed tools for the study of stability in hybrid systems, we recast the tracking problem as the task of asymptotically stabilizing a set, the tracking set, and derive conditions for the design of state-feedback tracking controllers with the property that the jump times of the plant coincide with those of the given reference trajectories. The resulting tracking controllers guarantee that solutions of the plant starting close to the reference trajectory stay close to it and that the difference between each solution of the controlled plant and the reference trajectory converges to zero asymptotically. Constructive conditions for tracking control design in terms of LMIs are proposed for a class of hybrid systems with linear maps and input-triggered jumps. The results are illustrated by various examples. Copyright {\textcopyright} 2013 John Wiley \& Sons, Ltd.

}, keywords = {hybrid systems}, issn = {1099-1239}, doi = {http://dx.doi.org/10.1002/rnc.2944}, url = {https://hybrid.soe.ucsc.edu/files/preprints/67.pdf}, author = {R. G. Sanfelice and J. J. B. Biemond and N. van de Wouw and W. P. M. H. Heemels} } @article {52, title = {Interconnections of Hybrid Systems: Some Challenges and Recent Results}, journal = {Journal of Nonlinear Systems and Applications}, volume = {2}, number = {1-2}, year = {2011}, pages = {111{\textendash}121}, keywords = {hybrid systems}, doi = {http://jnsaonline.watsci.org/abstract_pdf/2011v2/v2n1-pdf/13.pdf}, url = {https://hybrid.soe.ucsc.edu/files/preprints/52.pdf}, author = {R. G. Sanfelice} } @article {45, title = {On singular perturbations due to fast actuators in hybrid control systems}, journal = {Automatica}, volume = {47}, number = {4}, year = {2011}, month = {April}, pages = {692{\textendash}701}, keywords = {hybrid systems}, doi = {http://www.sciencedirect.com/science/article/pii/S0005109811000707}, url = {https://hybrid.soe.ucsc.edu/files/preprints/45.pdf}, author = {R. G. Sanfelice and A. R. Teel} } @article {35, title = {Asymptotic stability in hybrid systems via nested {M}atrosov functions}, journal = {IEEE Transactions on Automatic Control}, volume = {54}, number = {7}, year = {2009}, pages = {1569{\textendash}1574}, abstract = {A theorem on nested Matrosov functions is extended to time-varying hybrid systems. It provides suf?cient conditions for uniform global asymptotic stability of a compact set. An application to parameter identi?cation with state resets is made and illustrated on an example.}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=5071164}, url = {https://hybrid.soe.ucsc.edu/files/preprints/35.pdf}, author = {R. G. Sanfelice and A. R. Teel} } @article {34, title = {Hybrid dynamical systems}, journal = {IEEE Control Systems Magazine}, volume = {29}, number = {2}, year = {2009}, month = {April}, pages = {28-93}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=4806347\&isnumber=4806311}, url = {https://hybrid.soe.ucsc.edu/files/preprints/34.pdf}, author = {R. Goebel and R. G. Sanfelice and A.R. Teel} } @article {29, title = {Generalized solutions to hybrid dynamical systems}, journal = {ESAIM: Control, Optimisation and Calculus of Variations}, volume = {14}, number = {4}, year = {2008}, pages = {699{\textendash}724}, abstract = {Several recent results in the area of robust asymptotic stability of hybrid systems show that the concept of a generalized solution to a hybrid system is suitable for the analysis and design of hybrid control systems. In this paper, we show that such generalized solutions are exactly the solutions that arise when measurement noise in the system is taken into account.}, keywords = {hybrid systems}, doi = {http://www.esaim-cocv.org/action/displayAbstract?fromPage=online\&aid=8133135\&fulltextType=RA\&doiId=S1292811908000080}, url = {https://hybrid.soe.ucsc.edu/files/preprints/29.pdf}, author = {R. G. Sanfelice and R. Goebel and A.R. Teel} } @article {22, title = {Invariance principles for switching systems via hybrid systems techniques}, journal = {Systems \& Control Letters}, volume = {57}, number = {12}, year = {2008}, month = {December}, pages = {980-986}, abstract = {Invariance principles and sufficient conditions for asymptotic stability for switching systems are given. Multiple Lyapunov-like functions are used, and dwell-time, persistent dwell-time, and weak dwell-time switching signals are considered. The invariance principles are derived from general invariance principles for hybrid systems. Asymptotic stability is concluded under observability assumptions or common bounds on the Lyapunov-like functions.}, keywords = {hybrid systems}, doi = {http://www.sciencedirect.com/science/article/pii/S0167691108001035}, url = {https://hybrid.soe.ucsc.edu/files/preprints/22.pdf}, author = {R. Goebel and R. G. Sanfelice and A. R. Teel} } @article {18, title = {Invariance principles for hybrid systems with connections to detectability and asymptotic stability}, journal = {IEEE Transactions on Automatic Control}, volume = {52}, number = {12}, year = {2007}, pages = {2282{\textendash}2297}, abstract = {The paper shows several versions of the (LaSalle{\textquoteright}s) invariance principle for general hybrid systems. The broad framework allows for nonuniqueness of solutions, Zeno behaviors, and does not insist on continuous dependence of solutions on initial conditions. Instead, only a mild structural property involving graphical convergence of solutions is posed. The general invariance results are then specified to hybrid systems given by set-valued data. Further results involving invariance as well as observability, detectability, and asymptotic stability are given.}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=04395187}, url = {https://hybrid.soe.ucsc.edu/files/preprints/18.pdf}, author = {R. G. Sanfelice and R. Goebel and A. R. Teel} } @conference {264, title = {Global Asymptotic Stability of Nonlinear Systems While Exploiting Properties of Uncertified Feedback Controllers Via Opportunistic Switching}, booktitle = {Proceedings of the American Control Conference}, year = {2022}, month = {June}, pages = {2663-2668}, keywords = {hybrid systems}, author = {P. K. Wintz and R. G. Sanfelice and J.P. Hespanha} } @conference {263, title = {A Class of Hybrid Geometric Controllers for Robust Global Asymptotic Stabilization on $S^1$}, booktitle = {Proceedings of the American Control Conference}, year = {2022}, month = {June}, pages = {874-879}, keywords = {hybrid systems}, author = {A. Akhtar and R. G. Sanfelice} } @conference {109, title = {Invariance Principles for Switched Differential-Algebraic Systems Under Arbitrary and Dwell-time Switching}, booktitle = {Proceedings of the American Control Conference}, series = {NULL}, year = {2015}, month = {June}, pages = {1788--1793}, keywords = {hybrid systems}, author = {P. Nanez and R. G. Sanfelice and N. Quijano} } @conference {108, title = {Observer-based Control Design for Linear Systems in the Presence of Limited Measurement Streams and Intermittent Input Access}, booktitle = {Proceedings of the American Control Conference}, series = {NULL}, year = {2015}, month = {June}, pages = {4689-4694}, keywords = {hybrid systems, observers}, author = {F. Ferrante and F. Gouaisbaut and R. G. Sanfelice and S. Tarbouriech} } @conference {107, title = {Global Exponential Stabilization on the $n$-Dimensional Sphere}, booktitle = {Proceedings of the American Control Conference}, series = {NULL}, year = {2015}, month = {June}, pages = {3218--3223}, keywords = {attitude control, hybrid systems}, author = {P. Casau and C. G. Mayhew and R. G. Sanfelice and C. Silvestre} } @conference {102, title = {Results on Incremental Stability for a Class of Hybrid Systems}, booktitle = {Proceedings of the 53rd IEEE Conference on Decision and Control}, series = {NULL}, year = {2014}, month = {December}, pages = {3089--3094}, abstract = {

Incremental stability is the notion that the distance between every pair of solutions to the system has stable behavior and approaches zero asymptotically. This paper introduces this notion for a class of hybrid systems. In particular, we define incremental stability as well as incremental partial stability, and study their properties. The approach used to derive our results consists of recasting the incremental stability problem as a set stabilization problem, for which the tools for asymptotic stability of hybrid systems are applicable. In particular, we propose an auxiliary hybrid system to study the stability of the diagonal set, which relates to incremental stability of the original system. The proposed notions are illustrated in examples throughout the paper.

}, keywords = {hybrid systems}, author = {Y. Li and S. Phillips and R. G. Sanfelice} } @conference {101, title = {A Hybrid Controller for Global Uniform Exponential Stabilization of Linear Systems with Singular Input Constraints}, booktitle = {Proceedings of the Conference on Decision and Control}, series = {NULL}, year = {2014}, month = {December}, pages = {741--746}, keywords = {attitude control, hybrid systems}, author = {P. Casau and R. G. Sanfelice and C. Silvestre} } @conference {94, title = {An Invariance Principle for Differential-Algebraic Equations with Jumps}, booktitle = {Proceedings of the 2014 American Control Conference}, series = {NULL}, year = {2014}, pages = {1426-1431}, keywords = {hybrid systems}, author = {P. Nanez and R. G. Sanfelice} } @conference {93, title = {A Framework for Modeling and Analysis of Robust Stability for Spiking Neurons}, booktitle = {Proceedings of the American Control Conference}, series = {NULL}, year = {2014}, month = {June}, pages = {1414-1419}, keywords = {hybrid systems}, author = {S. Phillips and R. G. Sanfelice} } @conference {92, title = {Sufficient Conditions for Passivity and Stability of Interconnections of Hybrid Systems using Sums of Storage Functions}, booktitle = {Proceedings of the 2014 American Control Conference}, series = {NULL}, year = {2014}, pages = {1432-1437}, keywords = {hybrid systems}, author = {R. Naldi and R. G. Sanfelice} } @conference {91, title = {A Robust Hybrid Control Algorithm for a Single-Phase DC/AC Inverter with Variable Input Voltage}, booktitle = {Proceedings of the 2014 American Control Conference}, series = {NULL}, year = {2014}, pages = {1420-1425}, keywords = {hybrid systems}, author = {J. Chai and R. G. Sanfelice} } @conference {85, title = {Pointwise Minimum-norm Control Laws for Hybrid Systems}, booktitle = {Proceedings of the IEEE Conference on Decision and Control}, series = {NULL}, year = {2013}, pages = {2665{\textendash}2670}, keywords = {hybrid systems}, url = {https://hybrid.soe.ucsc.edu/files/preprints/85.pdf}, author = {R. G. Sanfelice} } @conference {83, title = {On the Stability of Hybrid Limit Cycles and Isolated Equilibria in a Genetic Network with Binary Hysteresis}, booktitle = {Proceedings of the IEEE Conference on Decision and Control}, series = {NULL}, year = {2013}, pages = {4080{\textendash}4085}, keywords = {hybrid systems}, url = {https://hybrid.soe.ucsc.edu/files/preprints/83.pdf}, author = {Q. Shu and R. G. Sanfelice} } @conference {82, title = {Hybrid Control of the Boost Converter: {R}obust Global Stabilization}, booktitle = {Proceedings of the IEEE Conference on Decision and Control}, series = {NULL}, year = {2013}, pages = {3635{\textendash}3640}, keywords = {hybrid systems}, author = {T. A. F. Theunisse and J. Chai and R. G. Sanfelice and W. P. M. H. Heemels} } @conference {80, title = {A Hybrid Model of a Genetic Regulatory Network in Mammalian Sclera}, booktitle = {Proceedings of the Hybrid Systems and Biology Workshop}, series = {NULL}, year = {2013}, keywords = {hybrid systems}, url = {https://hybrid.soe.ucsc.edu/files/preprints/80.pdf}, author = {Q. Shu and C. Ardilla and R. G. Sanfelice and J. P. Vande Geest} } @conference {79, title = {Juggling On A Bouncing Ball Apparatus Via Hybrid Control}, booktitle = {Proceedings of the IEEE/RSJ International Conference on Intelligent Robots and Systems}, series = {NULL}, year = {2013}, pages = {1848{\textendash}1853}, keywords = {hybrid systems}, url = {https://hybrid.soe.ucsc.edu/files/preprints/79.pdf}, author = {X. Tian and J. H. Koessler and R. G. Sanfelice} } @conference {78, title = {Suboptimality Bounds for Linear Quadratic Problems in Hybrid Linear Systems}, booktitle = {Proceedings of the European Control Conference}, series = {NULL}, year = {2013}, pages = {2663{\textendash}2668}, keywords = {hybrid systems}, url = {https://hybrid.soe.ucsc.edu/files/preprints/78.pdf}, author = {Y. Kouhi and N. Bajcinca and R. G. Sanfelice} } @conference {76, title = {Optimal Lunar Landing and Retargeting using a Hybrid Control Strategy}, booktitle = {Proceedings of AAS/AIAA Space Flight Mechanics Meeting}, series = {NULL}, year = {2013}, month = {February}, keywords = {hybrid systems}, author = {D.R. Wibben and R. Furfaro and R. G. Sanfelice} } @conference {72, title = {Results on the Asymptotic Stability Properties of Desynchronization in Impulse-coupled Oscillators}, booktitle = {Proceedings of the American Control Conference}, series = {NULL}, year = {2013}, month = {June}, pages = {3278{\textendash}3283}, keywords = {hybrid systems}, url = {https://hybrid.soe.ucsc.edu/files/preprints/72.pdf}, author = {S. Phillips and R. G. Sanfelice} } @conference {64, title = {Tracking control of mechanical systems with a unilateral position constraint inducing dissipative impacts}, booktitle = {Proceedings of the IEEE Conference on Decision and Control}, series = {NULL}, year = {2012}, pages = {4223{\textendash}4228}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=6426527}, url = {https://hybrid.soe.ucsc.edu/files/preprints/64.pdf}, author = {J. J. B. Biemond and N. van de Wouw and W. P. M. H. Heemels and R. G. Sanfelice and H. Nijmeijer} } @conference {63, title = {Switching System Model for Pinpoint Lunar Landing Guidance Using a Hybrid Control Strategy}, booktitle = {Proceedings of the AIAA Guidance, Navigation, and Control Conference}, series = {NULL}, year = {2012}, keywords = {hybrid systems}, doi = {http://arc.aiaa.org/doi/abs/10.2514/6.2012-4919}, url = {https://hybrid.soe.ucsc.edu/files/preprints/63.pdf}, author = {D. R. Wibben and R. Furfaro and R. G. Sanfelice} } @conference {62, title = {Self-Triggering in Nonlinear Systems: A Small Gain Theorem Approach}, booktitle = {Proceedings of the 20th Mediterranean Conference on Control and Automation}, series = {NULL}, year = {2012}, pages = {941{\textendash}947}, keywords = {hybrid systems}, url = {https://hybrid.soe.ucsc.edu/files/preprints/62.pdf}, author = {D. Tolic and R. G. Sanfelice and R. Fierro} } @conference {61, title = {On the Synchronization of Two Impulsive Oscillators under Communication Constraints}, booktitle = {Proceedings of the American Control Conference}, series = {NULL}, year = {2012}, pages = {2443{\textendash}2448}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/xpl/articleDetails.jsp?tp=\&arnumber=6315647}, url = {https://hybrid.soe.ucsc.edu/files/preprints/61.pdf}, author = {S. Phillips and R. G. Sanfelice and R. S. Erwin} } @conference {55, title = {Passivity-based Controllers for a Class of Hybrid Systems with Applications to Mechanical Systems Interacting with their Environment}, booktitle = {Proc. Joint Conference on Decision and Control and European Control Conference}, series = {NULL}, year = {2011}, pages = {7416{\textendash}7421}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=6161066\&tag=1}, url = {https://hybrid.soe.ucsc.edu/files/preprints/55.pdf}, author = {R. Naldi and R. G. Sanfelice} } @conference {54, title = {Further results on synergistic {L}yapunov functions and hybrid feedback design through backstepping}, booktitle = {Proc. Joint Conference on Decision and Control and European Control Conference}, series = {NULL}, year = {2011}, pages = {7428{\textendash}7433}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=6161283}, author = {C. G. Mayhew and R. G. Sanfelice and A. R. Teel} } @conference {51, title = {Tracking Control for Hybrid Systems via Embedding of Known Reference Trajectories}, booktitle = {Proc. 30th American Control Conference}, series = {NULL}, year = {2011}, pages = {869{\textendash}874}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=5991500}, url = {https://hybrid.soe.ucsc.edu/files/preprints/51.pdf}, author = {R. G. Sanfelice and J. J. B. Biemond and N. van de Wouw and W. P. M. H. Heemels} } @conference {49, title = {Synergistic {L}yapunov functions and backstepping hybrid feedbacks}, booktitle = {Proc. 30th American Control Conference}, series = {NULL}, year = {2011}, pages = {3203{\textendash}3208}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=5991021}, author = {C. G. Mayhew and R. G. Sanfelice and A. R. Teel} } @conference {46, title = {Hybrid Controllers for Tracking of Impulsive Reference Trajectories: A Hybrid Exosystem Approach}, booktitle = {Proc. 14th International Conference Hybrid Systems: Control and Computation}, series = {NULL}, year = {2011}, pages = {231{\textendash}240}, keywords = {hybrid systems}, url = {https://hybrid.soe.ucsc.edu/files/preprints/46.pdf}, author = {M. Robles and R. G. Sanfelice} } @conference {44, title = {Results on Input-to-Output and Input-Output-to-State Stability for Hybrid Systems and their Interconnections}, booktitle = {Proc. 49th IEEE Conference on Decision and Control}, series = {NULL}, year = {2010}, pages = {2396{\textendash}2401}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/iel5/5707200/5716927/05718164.pdf?arnumber=5718164}, url = {https://hybrid.soe.ucsc.edu/files/preprints/44.pdf}, author = {R. G. Sanfelice} } @conference {42, title = {Uniting Two Output-Feedback Hybrid Controllers with Different Objectives}, booktitle = {Proc. 29th American Control Conference}, series = {NULL}, year = {2010}, pages = {910{\textendash}915}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/xpl/articleDetails.jsp?tp=\&arnumber=5530480}, url = {https://hybrid.soe.ucsc.edu/files/preprints/42.pdf}, author = {R. G. Sanfelice and C. Prieur} } @conference {33, title = {Supervising a family of hybrid controllers for robust global asymptotic stabilization}, booktitle = {Proc. 47th IEEE Conference on Decision and Control}, series = {NULL}, year = {2008}, pages = {4700{\textendash}4705}, abstract = {This paper describes an algorithm for achieving robust, global asymptotic stabilization in nonlinear control systems by supervising the actions of a family of hybrid controllers. The family is such that the regions over which they operate cover the state space in an appropriate sense. Moreover, their behavior is such that they can be scheduled to move the state of the system toward a desirable region, whether it be an equilibrium point or a compact set. In establishing our main result, we use the concept of ?events? for hybrid systems and show that, under mild assumptions, stability of a system without events is preserved when a ?nite number of events are incorporated. The algorithm is applied to robust, global stabilization problems involving vehicle orientation, position and orientation of a mobile robot, and the inverted con?guration of a pendulum.}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=4739481\&isnumber=4738560}, url = {https://hybrid.soe.ucsc.edu/files/preprints/33.pdf}, author = {R. G. Sanfelice and A. R. Teel and R. Goebel} } @conference {32, title = {Analysis of hybrid systems resulting from hysteresis and saturation: a {L}yapunov approach}, booktitle = {Proc. 47th IEEE Conference on Decision and Control}, series = {NULL}, year = {2008}, pages = {2764{\textendash}2769}, abstract = {This paper studies a class of hybrid systems with linear (or linear plus saturated linear) continuous and discrete dynamics, which are determined by a ?ow map and jump map, and state-triggered jumps. One motivation for considering this class of systems is that they can model control systems with a relay-type hysteresis element. Based on Lyapunov theorems for hybrid systems, a Lyapunov function is constructed that effectively incorporates the feature of the jumps. Global asymptotic stability analysis is presented for the case when the ?ow map is linear, and local asymptotic stability analysis is presented for the case when the ?ow map is linear plus saturated linear. The stability conditions are derived as matrix inequalities. A numerical example is presented to illustrate the hybrid modeling process for a system experiencing hysteresis. Simulations con?rm the effectiveness of the proposed analysis tools and demonstrate the potential of the Lyapunov function.}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=4739453\&isnumber=4738560}, url = {https://hybrid.soe.ucsc.edu/files/preprints/32.pdf}, author = {D. Dai and R. G. Sanfelice and T. Hu and A. R. Teel} } @conference {31, title = {Optimal Control of Mixed Logical Dynamical Systems with Linear Temporal Logic Specifications}, booktitle = {Proc. 47th IEEE Conference on Decision and Control}, series = {NULL}, year = {2008}, pages = {2117{\textendash}2122}, abstract = {Recently, Linear Temporal Logic (LTL) has been employed as a tool for formal speci?cation in dynamical control systems. With this formal approach, control systems can be designed to provably accomplish a large class of complex tasks speci?ed via LTL. For this purpose, language generating Buchi automata with ?nite abstractions of dynamical systems have been used in the literature. In this paper, we take a mathematical programming-based approach to control of a broad class of discrete-time dynamical systems, called Mixed Logic Dynamical (MLD) systems, with LTL speci?cations. MLDs include discontinuous and hybrid piecewise discrete-time linear systems. We apply these tools for model checking and optimal control of MLD systems with LTL speci?cations. Our algorithms exploit Mixed Integer Linear Programming (MILP) as well as, in the appropriate setting, Mixed Integer Quadratic Programming (MIQP) techniques. Our solution approach introduces a general technique useful in representing LTL constraints as mixed-integer linear constraints}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=4739370\&isnumber=4738560}, url = {https://hybrid.soe.ucsc.edu/files/preprints/31.pdf}, author = {S. Karaman and R. G. Sanfelice and E. Frazzoli} } @conference {30, title = {Robust hybrid source-seeking algorithms based on directional derivatives and their approximations}, booktitle = {Proc. 47th IEEE Conference on Decision and Control}, series = {NULL}, year = {2008}, pages = {1735{\textendash}1740}, abstract = {A family of hybrid control algorithms is developed that steer a nonholonomic autonomous vehicle to the source of a scalar signal present in the environment. In an idealized setting, we develop a general hybrid control scheme that globally asymptotically stabilizes the vehicle position about the source. Pursuing a practical implementation, a series of perturbations to the family of controllers is introduced, resulting in a semiglobal practical stability of the vehicle position about the source. An example of a recently developed conjugate direction-based controller ?tting into this family is developed and demonstrated by simulation and experiment.}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=4739392\&isnumber=4738560}, url = {https://hybrid.soe.ucsc.edu/files/preprints/30.pdf}, author = {C. G. Mayhew and R. G. Sanfelice and A. R. Teel} } @conference {27, title = {A Nested {M}atrosov Theorem for Hybrid Systems}, booktitle = {Proc. 27th American Control Conference}, series = {NULL}, year = {2008}, pages = {2915{\textendash}2920}, abstract = {We present a sufficient condition for uniform global asymptotic stability of compact sets for hybrid systems. Uniform global asymptotic stability (UGAS {\textendash} in the sense that bounds on the solutions and on the convergence time depend only on the distance to the compact set of interest) are introduced for a large class of hybrid systems which are given by a flow map, flow set, jump map, and jump set. We show that uniform global stability of a compact set plus the existence of Lyapunov-like functions and continuous functions satisfying a nested condition on the flow and jump sets imply uniform global asymptotic stability of the compact set. The required nested condition for hybrid systems turns out to be a combination of the conditions in nested Matrosov theorems for time-varying continuous-time and discrete-time available in the literature. Our result also show that Matrosov{\textquoteright}s theorem are a reasonable alternative to LaSalle{\textquoteright}s invariance principle for time-invariant systems when additional functions with certain decreasing properties are available. We illustrate the application of our main result in several examples, including the so-called bouncing ball system.}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=4586938\&isnumber=4586444:PDF;SLIDES:Talks/ACC2008-ThB14-5.pdf:PowerPoint}, url = {https://hybrid.soe.ucsc.edu/files/preprints/27.pdf}, author = {R. G. Sanfelice and A. R. Teel} } @conference {26, title = {A Hybrid Control Framework for Robust Maneuver-based motion planning}, booktitle = {Proc. 27th American Control Conference}, series = {NULL}, year = {2008}, pages = {2254{\textendash}2259}, abstract = {We introduce a modeling framework for robustness of maneuver-based motion planning algorithms for nonlinear systems with symmetries. Our framework implements a hybrid controller that robustly combines motion primitives from a pre-defined library. The closed-loop system is viewed as a hybrid system with flows given by a differential equation, jumps given by a difference equation, and two sets where these dynamics are allowed. We show that our hybrid controller for implementation of motion planning algorithms confers to the closed-loop system robustness properties to a large class of perturbations.}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=4586827\&isnumber=4586444:PDF;SLIDES:Talks/ACC2008-ThA14-2.pdf:PowerPoint}, url = {https://hybrid.soe.ucsc.edu/files/preprints/26.pdf}, author = {R. G. Sanfelice and E. Frazzoli} } @conference {25, title = {Robust global swing-up of the pendubot via hybrid control}, booktitle = {Proc. 27th American Control Conference}, series = {NULL}, year = {2008}, pages = {1424{\textendash}1429}, abstract = {Combining local state-feedback laws and open-loop schedules, we design a hybrid control algorithm for robust global stabilization of the pendubot to the upright configuration (both links straight up with zero velocity). Our hybrid controller performs the swing-up task robustly by executing a decision-making algorithm designed to work under the presence of perturbations. The hybrid control algorithm features logic variables, timers, and hysteresis. We explicitly design the control strategy and implement it in a real pendubot system using Matlab/Simulink with Real-time Workshop. Experimental results show the main capabilities of our hybrid controller.}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=4586692\&isnumber=4586444:PDF;SLIDES:Talks/ACC2008-WeC05-4.pdf:PowerPoint}, url = {https://hybrid.soe.ucsc.edu/files/preprints/25.pdf}, author = {R. O{\textquoteright}Flaherty and R. G. Sanfelice and A. R. Teel} } @conference {24, title = {Robust source-seeking hybrid controllers for nonholonomic vehicles}, booktitle = {Proc. 27th American Control Conference}, series = {NULL}, year = {2008}, pages = {2722{\textendash}2727}, abstract = {We consider the problem of steering a nonholonomic vehicle to the source of a radiation-like signal with only measurements of the signal. We propose a general control strategy for vehicle steering which is based on an optimization algorithm for minimization of nonlinear functions without gradient information. We state the main properties of the strategy and specialize it to the control of nonholonomic vehicles. We discuss its implementation in a hybrid controller which coordinates vehicle steering and logic elements. We present global convergence and stability results for the closed-loop system. We also discuss two possible modifications to our algorithm that improve its performance when applied to real-world environments.}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=4586904\&isnumber=4586444}, url = {https://hybrid.soe.ucsc.edu/files/preprints/24.pdf}, author = {C. G. Mayhew and R. G. Sanfelice and A. R. Teel} } @conference {23, title = {On the optimality of {D}ubins paths across heterogeneous terrain}, booktitle = {Hybrid Systems: Computation and Control}, series = {Lecture Notes in Computer Science}, volume = {4981}, year = {2008}, pages = {457-470}, publisher = {Springer Berlin / Heidelberg}, organization = {Springer Berlin / Heidelberg}, chapter = {On the optimality of {D}ubins paths across heterogeneous terrain}, abstract = {We derive optimality conditions for the paths of Dubins vehicle when the state space is given by the union of two patches with different vehicle constant forward velocity. We recast this problem as a hybrid optimal control problem and solve it using recent optimality principles for hybrid systems. Among the optimality conditions, we derive a {\textquoteleft}{\textquoteleft}refraction" law at the boundary of the patches which generalizes the so-called Snell{\textquoteright}s law of refraction in optics to the case of paths with bounded maximum curvature.}, keywords = {hybrid systems}, doi = {http://www.springerlink.com/content/c3g1478530540265/fulltext.pdf:PDF;HTML:http\://www.springerlink.com/content/c3g1478530540265/:URL}, url = {https://hybrid.soe.ucsc.edu/files/preprints/23.pdf}, author = {R. G. Sanfelice and E. Frazzoli} } @conference {19, title = {Hybrid {MPC}: Open-minded but not Easily Swayed}, booktitle = {Assessment and Future Directions of Nonlinear Model Predictive Control}, series = {NULL}, volume = {Lecture Notes in Control and Information Sciences 358}, year = {2007}, pages = {17{\textendash}34}, publisher = {Springer Berlin / Heidelberg}, organization = {Springer Berlin / Heidelberg}, chapter = {Hybrid {MPC}: Open-minded but not Easily Swayed}, abstract = {The robustness of asymptotic stability with respect to measurement noise for discrete-time feedback control systems is discussed. It is observed that, when attempting to achieve obstacle avoidance or regulation to a disconnected set of points for a continuous-time system using sample and hold state feedback, the noise robustness margin necessarily vanishes with the sampling period. With this in mind, we propose two modifications to standard model predictive control (MPC) to enhance robustness to measurement noise. The modifications involve the addition of dynamical states that make large jumps. Thus, they have a hybrid flavor. The proposed algorithms are well suited for situations where control algorithms must respond quickly to large changes in operating conditions but not be easily confused by moderately large measurement noise and similar disturbances.}, keywords = {hybrid systems}, doi = {http://www.springerlink.com/content/22236583418rr285/fulltext.pdf}, url = {https://hybrid.soe.ucsc.edu/files/preprints/19.pdf}, author = {S. E. Tuna and R. G. Sanfelice and M. J. Messina and A. R. Teel} } @conference {17, title = {A hybrid systems approach to trajectory tracking control for juggling systems}, booktitle = {Proc. 46th IEEE Conference on Decision and Control}, series = {NULL}, year = {2007}, pages = {5282{\textendash}5287}, address = {New Orleans, LA}, abstract = {From a hybrid systems point of view, we provide a modeling framework and a trajectory tracking control design methodology for juggling systems. We present the main ideas and concepts in a one degree-of-freedom juggler, which consists of a ball bouncing on an actuated robot. We design a hybrid control strategy that, with only information of the ball{\textquoteright}s state at impacts, controls the ball to track a reference rhythmic pattern with arbitrary precision. We extend this hybrid control strategy to the case of juggling multiple balls with different rhythmic patterns. Simulation results for juggling of one and three balls with a single actuated robot are presented.}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=4435010\&isnumber=4434000:PDF;SLIDES:Users/ricardo/public_html.MIT/Talks/CDC2007-FrB04-4.pdf:PowerPoint}, url = {https://hybrid.soe.ucsc.edu/files/preprints/17.pdf}, author = {R. G. Sanfelice and A. R. Teel and R. Sepulchre} } @conference {16, title = {Complex hybrid systems: stability analysis for omega limit sets}, booktitle = {Proc. 26th Chinese Control Conference}, series = {NULL}, year = {2007}, abstract = {This paper focuses on the asymptotic stability properties of omega limit sets for complex hybrid dynamical systems, which are commonly found in systems and engineering. It spells out specific stability results that follow when a hybrid dynamical system has certain structure, e.g., when it admits a decomposition resembling a cascade of hybrid dynamical systems.}, keywords = {hybrid systems}, url = {https://hybrid.soe.ucsc.edu/files/preprints/16.pdf}, author = {C. Cai and R. Goebel and R. G. Sanfelice and A.R. Teel} } @conference {15, title = {Hybrid systems techniques for convergence of solutions to switched systems}, booktitle = {Proc. 46th IEEE Conference on Decision and Control}, series = {NULL}, year = {2007}, pages = {92{\textendash}96}, abstract = {Invariance principles for hybrid systems are used to derive invariance principles for nonlinear switching systems with multiple Lyapunov-like functions. Dwell-time, persistent dwell-time, and weak dwell-time solutions are considered. Asymptotic stability results are deduced under observability assumptions or common bounds on the Lyapunov-like functions.}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=4435008\&isnumber=4434000}, url = {https://hybrid.soe.ucsc.edu/files/preprints/15.pdf}, author = {R. Goebel and R. G. Sanfelice and A.R. Teel} } @conference {14, title = {{H}ybrid {S}ystems: stability and control}, booktitle = {Proc. 26th Chinese Control Conference}, series = {NULL}, year = {2007}, chapter = {Hybrid systems: limit sets and zero dynamics with a view toward output regulation}, abstract = {We present results on omega-limit sets and minimum phase zero dynamics for hybrid dynamical systems. Moreover, we give pointers to how these results may be useful in the future for solving the output regulation problem for hybrid systems. We highlight the main attributes of omega-limit sets and we show, under mild conditions, that they are asymptotically stable. We define a minimum phase notion in terms of omega-limit sets and establish an equivalent Lyapunov characterization. Then we study the feedback stabilization problem for a class of minimum phase, relative degree one hybrid systems. Finally, we discuss output regulation for this class of hybrid systems. We illustrate the concepts with examples throughout the paper.}, keywords = {hybrid systems}, url = {https://hybrid.soe.ucsc.edu/files/preprints/14.pdf}, author = {C. Cai and R. Goebel and R. G. Sanfelice and A. R. Teel} } @conference {13, title = {A hybrid control strategy for robust contact detection and force regulation}, booktitle = {Proc. 26th American Control Conference}, series = {NULL}, year = {2007}, pages = {1461{\textendash}1466}, abstract = {We present an innovative hybrid control strategy for contact detection and force regulation of robotic manipulators. This hybrid architecture controls the robotic manipulator during the following stages of interaction with the work environment: the free motion, the transition phase, and the constrained motion. The proposed control strategy is to switch between a position and a force controller with hysteresis relying only on contact force measurements. We implement this strategy in a hybrid controller and provide a design procedure which depends on the viscoelastic parameters of the work environment. Our controller guarantees contact detection and force regulation without bounce-off effects between the robotic manipulator and the work environment from compact sets of initial conditions. Additionally, the resulting closed-loop system is robust to measurement noise. We include simulations that show how the proposed hybrid control strategy guarantees good performance in the cases of stiff and compliant work environments, and in the presence of measurement noise.}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/iel5/4282134/4282135/04283119.pdf?tp=\&isnumber=4282135\&arnumber=4283119\&punumber=\%3Cb\%3E\%3Cfont\%20color=990000\%3E4282134\%3C/font\%3E\%3C/b\%3E}, url = {https://hybrid.soe.ucsc.edu/files/preprints/13.pdf}, author = {R. Carloni and R. G. Sanfelice and A. R. Teel and C. Melchiorri} } @conference {12, title = {Robust source seeking hybrid controllers for autonomous vehicles}, booktitle = {Proc. 26th American Control Conference}, series = {NULL}, year = {2007}, pages = {1185{\textendash}1190}, abstract = {

We consider the problem of steering an autonomous vehicle to locate a radiation source utilizing measurements of the radiation intensity only. We propose a control algorithm that locates the source through a sequence of line minimizations of the radiation intensity. We implement in a hybrid controller, with sample-and-hold and logic variables, a discretized version of the algorithm suitable for steering a point-mass vehicle. The algorithm confers global convergence and practical stability properties to the closed-loop hybrid system. We discuss these properties and characterize the region of convergence for the vehicle. Convergence and stability results are supplemented with simulations.

}, keywords = {hybrid systems}, doi = {http://www.scivee.tv/node/2725,http\://ieeexplore.ieee.org/iel5/4282134/4282135/04283016.pdf?tp=\&isnumber=4282135\&arnumber=4283016\&punumber=\%3Cb\%3E\%3Cfont\%20color=990000\%3E4282134\%3C/font\%3E\%3C/b\%3E}, url = {https://hybrid.soe.ucsc.edu/files/preprints/12.pdf}, author = {C. G. Mayhew and R. G. Sanfelice and A. R. Teel} } @conference {11, title = {A {\textquoteleft}{\textquoteleft}throw-and-catch" hybrid control strategy for robust global stabilization of nonlinear systems}, booktitle = {Proc. 26th American Control Conference}, series = {NULL}, year = {2007}, pages = {3470{\textendash}3475}, abstract = {We present a control strategy that combines local state feedback laws and open-loop schedules to robustly globally asymptotically stabilize a compact subset (typically a point) of the state space for a nonlinear system. The control algorithm is illustrated on the problem of global stabilization of the upright position of the pendubot and implemented in a hybrid controller containing logic variables and logic rules with hysteresis. We also present the design procedure of the hybrid controller for general nonlinear systems. Recent results in the literature on robustness of asymptotic stability in hybrid systems are used in establishing that the closed-loop system is robust to measurement noise and other external disturbances.}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=4282778}, url = {https://hybrid.soe.ucsc.edu/files/preprints/11.pdf}, author = {R. G. Sanfelice and A. R. Teel} } @conference {10, title = {On the robustness to measurement noise and unmodeled dynamics of stability in hybrid systems}, booktitle = {Proc. 25th American Control Conference}, series = {NULL}, year = {2006}, pages = {4061{\textendash}4066}, abstract = {

Results on robustness to measurement noise and unmodeled dynamics of stability in hybrid systems are presented. We show that arbitrarily small measurement noise can lead to lack of existence of solutions in hybrid systems. One solution to this problem is to pass the measurements through a filter. Robustness to measurement noise using this filtering is shown explicitly. We also study the effect of unmodeled sensor/actuator dynamics in the closed loop and we demonstrate that stability is robust to a class of singular perturbations. The results are illustrated for the inverted pendulum on a cart system when attempting to globally asymptotically stabilize the inverted position of the pendulum and the neutral cart position.

}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/iel5/11005/34689/01657354.pdf?tp=\&arnumber=1657354\&isnumber=34689}, url = {https://hybrid.soe.ucsc.edu/files/preprints/10.pdf}, author = {R. G. Sanfelice and A. R. Teel and R. Goebel and C. Prieur} } @conference {9, title = {{L}yapunov analysis of sample-and-hold hybrid feedbacks}, booktitle = {Proc. 45th IEEE Conference on Decision and Control}, series = {NULL}, year = {2006}, pages = {4879{\textendash}4884}, abstract = {

For hybrid closed-loop systems arising from hybrid control of nonlinear systems, we show that the sampleand-hold implementation of the hybrid controller preserves (semiglobally and practically) the stability properties of the closed-loop system. We provide a general model for the hybrid closed-loop system where the hybrid controller is implemented digitally and it is interfaced to the nonlinear system through sample and hold devices. We model the sample device and the digital controller/hold device as single asynchronous hybrid systems with independent timing constants and data. The main result is established by means of a Lyapunov function for the hybrid closed-loop system resulting from the interconnection of its hybrid and nonlinear subsystems.

}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/iel5/4176992/4176993/04177901.pdf?tp=\&isnumber=4176993\&arnumber=4177901\&punumber=\%3Cb\%3E\%3Cfont\%20color=990000\%3E4176992\%3C/font\%3E\%3C/b\%3E}, url = {https://hybrid.soe.ucsc.edu/files/preprints/9.pdf}, author = {R. G. Sanfelice and A. R. Teel} } @conference {7, title = {Robust hybrid controllers for continuous-time systems with applications to obstacle avoidance and regulation to disconnected set of points}, booktitle = {Proc. 25th American Control Conference}, series = {NULL}, year = {2006}, pages = {3352{\textendash}3357}, abstract = {

We give an elementary proof of the fact that, for continuous-time systems, it is impossible to use (even discontinuous) pure state feedback to achieve robust global asymptotic stabilization of a disconnected set of points or robust global regulation to a target while avoiding an obstacle. Indeed, we show that arbitrarily small, piecewise constant measurement noise can keep the trajectories away from the target. We give a constructive, Lyapunov-based hybrid state feedback that achieves robust regulation in the above mentioned settings.

}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/iel5/11005/34689/01657236.pdf?tp=\&isnumber=\&arnumber=1657236}, url = {https://hybrid.soe.ucsc.edu/files/preprints/7.pdf}, author = {R. G. Sanfelice and M. J. Messina and S. E. Tuna and A. R. Teel} } @conference {6, title = {A feedback control motivation for generalized solutions to hybrid systems}, booktitle = {Hybrid Systems: Computation and Control, Lecture Notes in Computer Science 3927}, series = {NULL}, year = {2006}, pages = {522{\textendash}536}, publisher = {Springer Berlin / Heidelberg}, organization = {Springer Berlin / Heidelberg}, abstract = {

Several recent results in the area of robust asymptotic stability of hybrid systems show that the concept of a generalized solution to a hybrid system is suitable for the analysis and design of hybrid control systems. In this paper, we show that such generalized solutions are exactly the solutions that arise when measurement noise is present in the system.

}, keywords = {hybrid systems}, doi = {http://www.springerlink.com/content/p1l0517700517248/fulltext.pdf}, url = {https://hybrid.soe.ucsc.edu/files/preprints/6.pdf}, author = {R. G. Sanfelice and R. Goebel and A.R. Teel}, editor = {J. P. Hespanha and A. Tiwari and J. P. Hespanha and A. Tiwari} } @conference {5, title = {On hybrid controllers that induce input-to-state stability with respect to measurement noise}, booktitle = {Proc. 44th IEEE Conference on Decision and Control and European Control Conference}, series = {NULL}, year = {2005}, pages = {4891{\textendash}4896}, abstract = {

For a class of nonlinear systems affine in controls and with unknown high frequency gain, we develop a hybrid control strategy that guarantees (practical) global input-to-state stability (ISS) with respect to measurement noise. We provide a design procedure for the hybrid controller and apply it to Freeman{\textquoteright}s counterexample and minimum-phase relative degree one systems.

}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/iel5/10559/33412/01582936.pdf?tp=\&arnumber=1582936\&isnumber=33412}, url = {https://hybrid.soe.ucsc.edu/files/preprints/5.pdf}, author = {R. G. Sanfelice and A. R. Teel} } @conference {4, title = {Results on convergence in hybrid systems via detectability and an invariance principle}, booktitle = {Proc. 24th American Control Conference}, series = {NULL}, year = {2005}, pages = {551{\textendash}556}, abstract = {

Two invariance principles for generalized hybrid systems are presented. One version involves the use of a nonincreasing function, like in the original work of LaSalle. The other version involves {\textquoteleft}{\textquoteleft}meagreness" conditions. These principles characterize asymptotic convergence of bounded hybrid trajectories to weakly invariant sets. A detectability property is used to locate a set in which the Omega-limit set of a trajectory is contained. Next, it is shown how the invariance principles can be used to certify asymptotic stability in hybrid systems. Lyapunov and Krasovskii theorems for hybrid systems are included.

}, keywords = {hybrid systems}, doi = {http://ieeexplore.ieee.org/iel5/9861/31519/01470014.pdf?tp=\&arnumber=1470014\&isnumber=31519}, url = {https://hybrid.soe.ucsc.edu/files/preprints/4.pdf}, author = {R. G. Sanfelice and R. Goebel and A.R. Teel} } @conference {3, title = {Hybrid systems: generalized solutions and robust stability}, booktitle = {Proc. 6th IFAC Symposium in Nonlinear Control Systems}, series = {NULL}, year = {2004}, pages = {1{\textendash}12}, abstract = {

Robust asymptotic stability for hybrid systems is considered. For this purpose, a generalized solution concept is developed. The first step is to characterize a hybrid time domain that permits an efiient description of the convergence of a sequence of solutions. Graph convergence is used. Then a generalized solution definition is given that leads to continuity with respect to initial conditions and perturbations of the system data. This property enables new results on necessary conditions for asymptotic stability in hybrid systems.

}, keywords = {hybrid systems}, doi = {http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.61.8882\&rep=rep1\&type=pdf}, url = {https://hybrid.soe.ucsc.edu/files/preprints/3.pdf}, author = {R. Goebel and J.P. Hespanha and A.R. Teel and C. Cai and R. G. Sanfelice} } @conference {1, title = {Novel current control for {AC} motors with low torque ripple}, booktitle = {Proc. IX Workshop on Information Processing and Control RPIC}, series = {NULL}, year = {2001}, abstract = {

In this paper a current-control strategy for AC induction motors is presented, that besides of minimizing the electromagnetic torque ripple in 50\% respect to the two-level hysteresis current-control, reduces the complexity of the same one as far as hardware and software resources. This complexity reduction causes a higher speed response, doesn{\textquoteright}t increase the commutation losses, and minimizes the perturbations and vibrations on the load of the motor. The simulation results and experimentation are analyzed.

}, keywords = {hybrid systems}, url = {https://hybrid.soe.ucsc.edu/files/preprints/1.pdf}, author = {M. Benedetti and J.F. Rovira and R. G. Sanfelice} }