@article {210,
	title = {Robust global exponential stabilization on the n-dimensional sphere with applications to trajectory tracking for quadrotors},
	journal = {Automatica},
	volume = {110},
	year = {2019},
	month = {December},
	author = {P. Casau and C. G. Mayhew and R. G. Sanfelice and C. Silvestre}
}
@article {68,
	title = {On Path-Lifting Mechanisms and Unwinding in Quaternion-based Attitude Control},
	journal = {IEEE Transactions on Automatic Control},
	volume = {58},
	number = {5},
	year = {2013},
	month = {May},
	pages = {1179{\textendash}1191},
	keywords = {attitude control},
	doi = {http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=6389715},
	author = {C. G. Mayhew and R. G. Sanfelice and A. R. Teel}
}
@article {58,
	title = {Quaternion-Based Hybrid Feedback for Robust Global Attitude Synchronization},
	journal = {IEEE Transactions on Automatic Control},
	volume = {57},
	number = {8},
	year = {2012},
	month = {August},
	pages = {2122{\textendash}2127},
	keywords = {attitude control},
	doi = {http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=6111242},
	url = {https://hybrid.soe.ucsc.edu/files/preprints/58.pdf},
	author = {C. G. Mayhew and R. G. Sanfelice and J. Sheng and M. Arcak and A. R. Teel}
}
@article {50,
	title = {Quaternion-Based Hybrid Controller for Robust Global Attitude Tracking},
	journal = {IEEE Transactions on Automatic Control},
	volume = {56},
	number = {11},
	year = {2011},
	month = {November},
	pages = {2555{\textendash}2566},
	keywords = {attitude control},
	doi = {http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=5701762},
	url = {https://hybrid.soe.ucsc.edu/files/preprints/50.pdf},
	author = {C. G. Mayhew and R. G. Sanfelice and A. R. Teel}
}
@conference {133,
	title = {Exponential Stabilization of a Vectored-Thrust Vehicle Using Synergistic Potential Functions},
	booktitle = {Proceedings of American Control Conference},
	year = {2016},
	pages = {6042--6047},
	author = {P. Casau and C. G. Mayhew and R. G. Sanfelice and C. Silvestre}
}
@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 {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 {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 {48,
	title = {On the Non-Robustness of Memoryless Path-Lifting Schemes for Quaternion-Based Attitude Control},
	booktitle = {Proc. 30th American Control Conference},
	series = {NULL},
	year = {2011},
	pages = {1003{\textendash}1008},
	keywords = {attitude control},
	doi = {http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=5991359},
	author = {C. G. Mayhew and R. G. Sanfelice and A. R. Teel}
}
@conference {47,
	title = {On Quaternion-Based Attitude Control and the Unwinding Phenomenon},
	booktitle = {Proc. 30th American Control Conference},
	series = {NULL},
	year = {2011},
	pages = {299{\textendash}304},
	keywords = {attitude control},
	doi = {http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=5991127},
	author = {C. G. Mayhew and R. G. Sanfelice and A. R. Teel}
}
@conference {41,
	title = {Robust Global Asymptotic Attitude Synchronization by Hybrid Control},
	booktitle = {Proc. 29th American Control Conference},
	series = {NULL},
	year = {2010},
	pages = {3666{\textendash}3671},
	keywords = {attitude control},
	doi = {http://ieeexplore.ieee.org/xpl/articleDetails.jsp?tp=\&arnumber=5530428},
	author = {C. G. Mayhew and R. G. Sanfelice and M. Arcak and A. R. Teel}
}
@conference {38,
	title = {Robust Global Asymptotic Attitude Stabilization of a Rigid Body by Quaternion-based Hybrid Feedback},
	booktitle = {Proc. 46th Conference on Decision and Control},
	series = {NULL},
	year = {2009},
	pages = {2522{\textendash}2527},
	abstract = {Global asymptotic stabilization of the attitude of a rigid body is made difficult by several topological obstructions. In fact, this task is impossible to accomplish with discontinuous state feedback. Moreover, when the attitude is parameterized with unit quaternions, it becomes impossible to design a globally stabilizing state feedback (even discontinuous) that is robust to measurement noise. In this paper, we present a quaternion-based hysteretic hybrid feedback that robustly globally asymptotically stabilizes the attitude of a rigid body. The hybrid control laws are derived through Lyapunov analysis in kinematic and dynamic settings. In the dynamic setting, we provide two control laws: one derived from a simple Lyapunov function, and another based on backstepping. Analyzing the change in these Lyapunov functions due to jumps of the hysteretic logic variable yields a straightforward form for state-based hysteretic switching points. A simulation study demonstrates robustness to measurement noise in the proposed control laws and differences between the non-backstepping and backstepping control laws.},
	keywords = {attitude control},
	doi = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=5400431},
	url = {https://hybrid.soe.ucsc.edu/files/preprints/38.pdf},
	author = {C. G. Mayhew and R. G. Sanfelice and A. R. Teel}
}
@conference {37,
	title = {Robust Global Asymptotic Stabilization of a 6-DOF Rigid Body by Quaternion-based Hybrid Feedback},
	booktitle = {Proc. 46th Conference on Decision and Control},
	series = {NULL},
	year = {2009},
	pages = {1094{\textendash}1099},
	abstract = {The problem of robust, global asymptotic stabilization of a rigid body is hampered by major topological obstructions. These obstructions prevent a continuous state feedback from solving the problem and also lead to robustness issues when discontinuous feedback is applied. In this paper, we extend a hybrid control strategy proposed in a companion paper for robust, global asymptotic stabilization of rigid body attitude to the case where translation is also considered. The quaternion-based hysteretic hybrid feedback laws are developed in the kinematic and dynamic settings. In the dynamic setting, two control laws are derived, one of which is based on backstepping. Robustness to measurement noise is asserted by employing recently developed stability theory for hybrid systems. The hybrid feedback is found to have desirable robustness properties.},
	keywords = {attitude control},
	doi = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=5400338},
	url = {https://hybrid.soe.ucsc.edu/files/preprints/37.pdf},
	author = {C. G. Mayhew and R. G. Sanfelice and A. R. Teel}
}
@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 {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 {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 = {<p>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.</p>},
	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}
}
