@article{7426,
abstract = {This paper presents a novel abstraction technique for analyzing Lyapunov and asymptotic stability of polyhedral switched systems. A polyhedral switched system is a hybrid system in which the continuous dynamics is specified by polyhedral differential inclusions, the invariants and guards are specified by polyhedral sets and the switching between the modes do not involve reset of variables. A finite state weighted graph abstracting the polyhedral switched system is constructed from a finite partition of the state–space, such that the satisfaction of certain graph conditions, such as the absence of cycles with product of weights on the edges greater than (or equal) to 1, implies the stability of the system. However, the graph is in general conservative and hence, the violation of the graph conditions does not imply instability. If the analysis fails to establish stability due to the conservativeness in the approximation, a counterexample (cycle with product of edge weights greater than or equal to 1) indicating a potential reason for the failure is returned. Further, a more precise approximation of the switched system can be constructed by considering a finer partition of the state–space in the construction of the finite weighted graph. We present experimental results on analyzing stability of switched systems using the above method.},
author = {Garcia Soto, Miriam and Prabhakar, Pavithra},
issn = {1751570X},
journal = {Nonlinear Analysis: Hybrid Systems},
number = {5},
publisher = {Elsevier},
title = {{Abstraction based verification of stability of polyhedral switched systems}},
doi = {10.1016/j.nahs.2020.100856},
volume = {36},
year = {2020},
}
@inproceedings{6493,
abstract = {We present two algorithmic approaches for synthesizing linear hybrid automata from experimental data. Unlike previous approaches, our algorithms work without a template and generate an automaton with nondeterministic guards and invariants, and with an arbitrary number and topology of modes. They thus construct a succinct model from the data and provide formal guarantees. In particular, (1) the generated automaton can reproduce the data up to a specified tolerance and (2) the automaton is tight, given the first guarantee. Our first approach encodes the synthesis problem as a logical formula in the theory of linear arithmetic, which can then be solved by an SMT solver. This approach minimizes the number of modes in the resulting model but is only feasible for limited data sets. To address scalability, we propose a second approach that does not enforce to find a minimal model. The algorithm constructs an initial automaton and then iteratively extends the automaton based on processing new data. Therefore the algorithm is well-suited for online and synthesis-in-the-loop applications. The core of the algorithm is a membership query that checks whether, within the specified tolerance, a given data set can result from the execution of a given automaton. We solve this membership problem for linear hybrid automata by repeated reachability computations. We demonstrate the effectiveness of the algorithm on synthetic data sets and on cardiac-cell measurements.},
author = {Garcia Soto, Miriam and Henzinger, Thomas A and Schilling, Christian and Zeleznik, Luka},
booktitle = {31st International Conference on Computer-Aided Verification},
isbn = {9783030255398},
issn = {0302-9743},
keywords = {Synthesis, Linear hybrid automaton, Membership},
location = {New York City, NY, USA},
pages = {297--314},
publisher = {Springer},
title = {{Membership-based synthesis of linear hybrid automata}},
doi = {10.1007/978-3-030-25540-4_16},
volume = {11561},
year = {2019},
}
@inproceedings{6565,
abstract = {In this paper, we address the problem of synthesizing periodic switching controllers for stabilizing a family of linear systems. Our broad approach consists of constructing a finite game graph based on the family of linear systems such that every winning strategy on the game graph corresponds to a stabilizing switching controller for the family of linear systems. The construction of a (finite) game graph, the synthesis of a winning strategy and the extraction of a stabilizing controller are all computationally feasible. We illustrate our method on an example.},
author = {Kundu, Atreyee and Garcia Soto, Miriam and Prabhakar, Pavithra},
booktitle = {5th Indian Control Conference Proceedings},
isbn = {978-153866246-5},
location = {Delhi, India},
publisher = {IEEE},
title = {{Formal synthesis of stabilizing controllers for periodically controlled linear switched systems}},
doi = {10.1109/INDIANCC.2019.8715598},
year = {2019},
}