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Xiwang Dong - One of the best experts on this subject based on the ideXlab platform.
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time varying output formation for linear multiagent systems via dynamic output feedback control
IEEE Transactions on Control of Network Systems, 2017Co-Authors: Xiwang DongAbstract:Time-varying output formation control problems for linear multiagent systems with directed interaction topologies are studied using a dynamic output feedback approach. First, a dynamic output formation protocol is constructed using the outputs of neighboring agents. Based on the output decomposition, observability decomposition and output formation decomposition, necessary and sufficient conditions for linear multiagent systems to achieve time-varying output formations are presented. An explicit expression of the output formation Reference Function is derived to describe the macroscopic movement of the entire output formation. Then, an algorithm with three steps is proposed to design the dynamic output formation protocol, where the gain matrices of the protocol can be determined by solving an algebraic Riccati equation. It is shown that if the dynamics of each agent is stabilizable, the solvability of the algorithm can be guaranteed. Moreover, a feasible time-varying output formation set is derived, and the stability of the proposed algorithm is proven based on the separation principle and Lyapunov stability theory. Finally, numerical simulation is presented to demonstrate the effectiveness of the theoretical results.
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time varying formation control for general linear multi agent systems with switching directed topologies
Automatica, 2016Co-Authors: Xiwang Dong, Guoqiang HuAbstract:Time-varying formation analysis and design problems for multi-agent systems with general linear dynamics and switching directed interaction topologies are investigated. Different from the previous results, the formation in this paper can be defined by specified piecewise continuously differentiable vectors and the switching topologies are directed. Firstly, necessary and sufficient conditions for general linear multi-agent systems with switching directed topologies to achieve time-varying formations are proposed, where a description of the feasible time-varying formation set and approaches to expand the feasible formation set are given. Then an explicit expression of the time-varying formation Reference Function is derived to describe the macroscopic movement of the whole formation. An approach to assign the motion modes of the formation Reference is provided. Moreover, an algorithm consisting of four steps to design the formation protocol is presented. In the case where the given time-varying formation belongs to the feasible formation set, it is proven that by designing the formation protocol using the proposed algorithm, time-varying formation can be achieved by multi-agent systems with general linear dynamics and switching directed topologies if the dwell time is larger than a positive threshold. Finally, numerical simulations are presented to demonstrate the effectiveness of the theoretical results.
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output formation containment analysis and design for general linear time invariant multi agent systems
Journal of The Franklin Institute-engineering and Applied Mathematics, 2016Co-Authors: Xiwang Dong, Qingdong Li, Yisheng ZhongAbstract:Abstract Output formation-containment control problems for general linear time-invariant multi-agent systems with directed topologies are dealt with. Output formation-containment means that the outputs of leaders achieve the predefined formation, and at the same time the outputs of followers converge to the convex hull formed by the outputs of leaders. Firstly, static output protocols are presented for leaders and followers respectively. Then output formation-containment problems of multi-agent systems are transformed into asymptotic stability problems. Sufficient conditions with less computation complexity are proposed for multi-agent systems to achieve the output formation-containment. An explicit expression for the time-varying output formation Reference Function is derived to describe the macroscopic movement of the whole output formation-containment. Explicit expressions to describe the relationship among the outputs of followers, the time-varying output formation for the leaders and the output formation Reference are derived. It is proven that the outputs of followers not only converge to the convex hull formed by those of leaders but also achieve certain time-varying formation specified by the convex combination of the desired output formation for the leaders. Moreover, an approach to determine the gain matrices in the protocols is given for multi-agent systems to achieve the output formation-containment. Finally, numerical simulations are provided to demonstrate the effectiveness of the theoretical results.
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time varying formation control for unmanned aerial vehicles with switching interaction topologies
Control Engineering Practice, 2016Co-Authors: Xiwang Dong, Yan Zhou, Yisheng ZhongAbstract:Abstract Time-varying formation control problems for unmanned aerial vehicle (UAV) swarm systems with switching interaction topologies are studied. Necessary and sufficient conditions for UAV swarm systems with switching interaction topologies to achieve predefined time-varying formations are proposed. Based on the common Lyapunov Functional approach and algebraic Riccati equation technique, an approach to design the formation protocol is presented. An explicit expression of the formation Reference Function is derived to describe the macroscopic movement of the whole UAV formation. A quadrotor formation platform consisting of four quadrotors is introduced. Outdoor experiments are performed to demonstrate the effectiveness of the theoretical results.
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formation containment analysis and design for high order linear time invariant swarm systems
International Journal of Robust and Nonlinear Control, 2015Co-Authors: Xiwang Dong, Geng Lu, Yisheng ZhongAbstract:Summary Formation-containment analysis and design problems for high-order linear time-invariant swarm systems with directed interaction topologies are dealt with respectively. Firstly, protocols are presented for leaders and followers respectively to drive the states of leaders to realize the predefined time-varying formation and propel the states of followers to converge to the convex hull formed by the states of leaders. Secondly, formation-containment problems of swarm systems are transformed into asymptotic stability problems, and an explicit expression of the formation Reference Function is derived. Sufficient conditions for swarm systems to achieve formation containment are proposed. Furthermore, necessary and sufficient conditions for swarm systems to achieve containment and time-varying formation are presented respectively as special cases. An approach to determine the gain matrices in the protocols is given. It is shown that containment problems, formation control problems, consensus problems and consensus tracking problems can all be treated as special cases of formation-containment problems. Finally, numerical simulations are provided to demonstrate theoretical results. Copyright © 2014 John Wiley & Sons, Ltd.
Yisheng Zhong - One of the best experts on this subject based on the ideXlab platform.
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output formation containment analysis and design for general linear time invariant multi agent systems
Journal of The Franklin Institute-engineering and Applied Mathematics, 2016Co-Authors: Xiwang Dong, Qingdong Li, Yisheng ZhongAbstract:Abstract Output formation-containment control problems for general linear time-invariant multi-agent systems with directed topologies are dealt with. Output formation-containment means that the outputs of leaders achieve the predefined formation, and at the same time the outputs of followers converge to the convex hull formed by the outputs of leaders. Firstly, static output protocols are presented for leaders and followers respectively. Then output formation-containment problems of multi-agent systems are transformed into asymptotic stability problems. Sufficient conditions with less computation complexity are proposed for multi-agent systems to achieve the output formation-containment. An explicit expression for the time-varying output formation Reference Function is derived to describe the macroscopic movement of the whole output formation-containment. Explicit expressions to describe the relationship among the outputs of followers, the time-varying output formation for the leaders and the output formation Reference are derived. It is proven that the outputs of followers not only converge to the convex hull formed by those of leaders but also achieve certain time-varying formation specified by the convex combination of the desired output formation for the leaders. Moreover, an approach to determine the gain matrices in the protocols is given for multi-agent systems to achieve the output formation-containment. Finally, numerical simulations are provided to demonstrate the effectiveness of the theoretical results.
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time varying formation control for unmanned aerial vehicles with switching interaction topologies
Control Engineering Practice, 2016Co-Authors: Xiwang Dong, Yan Zhou, Yisheng ZhongAbstract:Abstract Time-varying formation control problems for unmanned aerial vehicle (UAV) swarm systems with switching interaction topologies are studied. Necessary and sufficient conditions for UAV swarm systems with switching interaction topologies to achieve predefined time-varying formations are proposed. Based on the common Lyapunov Functional approach and algebraic Riccati equation technique, an approach to design the formation protocol is presented. An explicit expression of the formation Reference Function is derived to describe the macroscopic movement of the whole UAV formation. A quadrotor formation platform consisting of four quadrotors is introduced. Outdoor experiments are performed to demonstrate the effectiveness of the theoretical results.
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formation containment analysis and design for high order linear time invariant swarm systems
International Journal of Robust and Nonlinear Control, 2015Co-Authors: Xiwang Dong, Geng Lu, Yisheng ZhongAbstract:Summary Formation-containment analysis and design problems for high-order linear time-invariant swarm systems with directed interaction topologies are dealt with respectively. Firstly, protocols are presented for leaders and followers respectively to drive the states of leaders to realize the predefined time-varying formation and propel the states of followers to converge to the convex hull formed by the states of leaders. Secondly, formation-containment problems of swarm systems are transformed into asymptotic stability problems, and an explicit expression of the formation Reference Function is derived. Sufficient conditions for swarm systems to achieve formation containment are proposed. Furthermore, necessary and sufficient conditions for swarm systems to achieve containment and time-varying formation are presented respectively as special cases. An approach to determine the gain matrices in the protocols is given. It is shown that containment problems, formation control problems, consensus problems and consensus tracking problems can all be treated as special cases of formation-containment problems. Finally, numerical simulations are provided to demonstrate theoretical results. Copyright © 2014 John Wiley & Sons, Ltd.
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formation containment control for high order linear time invariant multi agent systems with time delays
Journal of The Franklin Institute-engineering and Applied Mathematics, 2015Co-Authors: Xiwang Dong, Qingdong Li, Yisheng ZhongAbstract:Abstract Formation-containment analysis and design problems for time-delayed high-order linear time-invariant multi-agent systems with directed interaction topologies are studied. Firstly, protocols with time delays are presented for leaders and followers, where the formation for leaders can be time-varying. Then formation-containment problems for time-delayed multi-agent systems are transformed into asymptotic stability problems of time-delayed systems. Sufficient conditions for multi-agent systems to achieve formation-containment are proposed, which include eight linear matrix inequalities independent of the number of leaders and followers. Furthermore, an explicit expression of the formation Reference Function for leaders is derived, where the motion modes of formation Reference can be specified. An approach to determine the gain matrices in the protocols is given using the method of changing variables. Finally, numerical simulations are provided to demonstrate theoretical results.
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time varying output formation control for high order linear time invariant swarm systems
Information Sciences, 2015Co-Authors: Xiwang Dong, Geng Lu, Yisheng ZhongAbstract:Formation control of swarm systems has gained considerable attention from scientific communities due to its potential applications in various areas. In practical applications, the dynamics of each agent may be of high order and only the outputs of all agents are required to achieve time-varying formations. Therefore, this paper focuses on time-varying output formation control problems for high-order linear time-invariant swarm systems with directed interaction topologies. A general output formation protocol is proposed based on the relative outputs of neighboring agents. Necessary and sufficient conditions for swarm systems to achieve time-varying output formations are presented using a consensus based approach. An explicit expression of the output formation Reference Function is given. For a swarm system, whether or not a desired output formation is feasible is a crucial problem. Based on partial stability theory, necessary and sufficient conditions for output formation feasibility are derived. Approaches to expand the feasible time-varying output formation set and an algorithm to design the protocol for swarm systems to achieve time-varying output formation are presented respectively. Finally, theoretical results are demonstrated by numerical simulations.
Geng Lu - One of the best experts on this subject based on the ideXlab platform.
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formation containment analysis and design for high order linear time invariant swarm systems
International Journal of Robust and Nonlinear Control, 2015Co-Authors: Xiwang Dong, Geng Lu, Yisheng ZhongAbstract:Summary Formation-containment analysis and design problems for high-order linear time-invariant swarm systems with directed interaction topologies are dealt with respectively. Firstly, protocols are presented for leaders and followers respectively to drive the states of leaders to realize the predefined time-varying formation and propel the states of followers to converge to the convex hull formed by the states of leaders. Secondly, formation-containment problems of swarm systems are transformed into asymptotic stability problems, and an explicit expression of the formation Reference Function is derived. Sufficient conditions for swarm systems to achieve formation containment are proposed. Furthermore, necessary and sufficient conditions for swarm systems to achieve containment and time-varying formation are presented respectively as special cases. An approach to determine the gain matrices in the protocols is given. It is shown that containment problems, formation control problems, consensus problems and consensus tracking problems can all be treated as special cases of formation-containment problems. Finally, numerical simulations are provided to demonstrate theoretical results. Copyright © 2014 John Wiley & Sons, Ltd.
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time varying output formation control for high order linear time invariant swarm systems
Information Sciences, 2015Co-Authors: Xiwang Dong, Geng Lu, Yisheng ZhongAbstract:Formation control of swarm systems has gained considerable attention from scientific communities due to its potential applications in various areas. In practical applications, the dynamics of each agent may be of high order and only the outputs of all agents are required to achieve time-varying formations. Therefore, this paper focuses on time-varying output formation control problems for high-order linear time-invariant swarm systems with directed interaction topologies. A general output formation protocol is proposed based on the relative outputs of neighboring agents. Necessary and sufficient conditions for swarm systems to achieve time-varying output formations are presented using a consensus based approach. An explicit expression of the output formation Reference Function is given. For a swarm system, whether or not a desired output formation is feasible is a crucial problem. Based on partial stability theory, necessary and sufficient conditions for output formation feasibility are derived. Approaches to expand the feasible time-varying output formation set and an algorithm to design the protocol for swarm systems to achieve time-varying output formation are presented respectively. Finally, theoretical results are demonstrated by numerical simulations.
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formation control for high order linear time invariant multiagent systems with time delays
IEEE Transactions on Control of Network Systems, 2014Co-Authors: Xiwang Dong, Geng Lu, Jianxiang Xi, Yisheng ZhongAbstract:Formation control problems for high-order linear time-invariant multiagent systems with time delays are investigated. First, a general time-varying formation control protocol is proposed. Then, based on consensus approaches, necessary and sufficient conditions for multiagent systems to achieve a given time-varying formation are presented. An explicit expression of the time-varying formation Reference Function is also given. It is shown that the motion modes of the formation Reference can be specified. Furthermore, necessary and sufficient conditions for formation feasibility are proposed. An approach to expand the feasible formation set and an algorithm to design the protocol for multiagent systems to achieve time-varying formations are provided, respectively. Finally, numerical simulations are presented to demonstrate theoretical results.
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time varying formation control for high order linear swarm systems with switching interaction topologies
Iet Control Theory and Applications, 2014Co-Authors: Xiwang Dong, Geng Lu, Yisheng ZhongAbstract:Time-varying formation control problems for high-order linear time-invariant swarm systems with switching interaction topologies are investigated. A general formation control protocol is proposed firstly. Then using a consensus based approach, necessary and sufficient conditions for swarm systems with switching interaction topologies to achieve a given time-varying formation are presented. An explicit expression of the time-varying formation Reference Function is given. It is revealed that the switching interaction topologies have no effect on the formation Reference Function and the motion modes of the formation Reference can be specified. Furthermore, necessary and sufficient conditions for formation feasibility are presented. An approach to expand the feasible formation set is given and an algorithm to design the protocol for swarm systems with switching interaction topologies to achieve time-varying formations is provided. Finally, numerical simulations are presented to demonstrate theoretical results.
Hans-joachim Werner - One of the best experts on this subject based on the ideXlab platform.
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A new internally contracted multi-Reference configuration interaction method.
The Journal of chemical physics, 2011Co-Authors: K. R. Shamasundar, Gerald Knizia, Hans-joachim WernerAbstract:We present a new internally contracted multi-Reference configuration interaction (MRCI) method which, at the same time, efficiently handles large active orbital spaces, long configuration expansions, and many closed-shell orbitals in the Reference Function. This is achieved by treating the closed-shell orbitals explicitly, so that all required coupling coefficients and density matrices only depend on active orbital labels. As a result, closed-shell orbitals are handled as efficiently as in a closed-shell single-Reference program, and this opens up the possibility to perform high-accuracy MRCI calculations for much larger molecules than before. The enormously complex equations are derived using a new domain-specific computer algebra system and semi-automatically implemented using a newly developed integrated tensor framework. The accuracy and efficiency of the MRCI method is demonstrated with applications to dioxygen-copper complexes with different ligands, some of which involve more than 30 atoms, and to spin-state splittings of ferrocene.
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A comparison of the efficiency and accuracy of the quadratic configuration interaction (QCISD), coupled cluster (CCSD), and Brueckner coupled cluster (BCCD) methods
Chemical Physics Letters, 1992Co-Authors: Claudia Hampel, Kirk A Peterson, Hans-joachim WernerAbstract:The coupled-cluster method restricted to single and double excitations from a closed-shell Reference Function (CCSD) and the corresponding quadratic configuration interaction method (QCISD) are formulated in terms of quantities which can be computed directly from the two-electron integrals in AO basis. A simple yet effective method to accelerate convergence in Brueckner coupled-cluster (BCCD) calculations is also described. Using this procedure BCCD calculations require no more effort than CCSD calculations. In order to compare the accuracy of all three methods potential energy Functions and spectroscopic constants have been calculated for N2, CO, F2, and HF using large basis sets. © 1992.
Kerstin Andersson - One of the best experts on this subject based on the ideXlab platform.
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different forms of the zeroth order hamiltonian in second order perturbation theory with a complete active space self consistent field Reference Function
Theoretical Chemistry Accounts, 1995Co-Authors: Kerstin AnderssonAbstract:A new one-particle zeroth-order Hamiltonian is proposed for perturbation theory with a complete active space self-consistent field (CASSCF) Reference Function. With the new partitioning of the Hamiltonian, Reference Functions dominated by a closed-shell configuration, on one hand, and an open-shell configuration, on the other hand, are treated in similar and balanced ways. This leads to a better description of excitation energies and dissociation energies. The new zeroth-order Hamiltonian has been tested on CH2, SiH2, NH2, CH3, N2, NO, and O2, for which full configuration interaction (FCI) results are available. Further, excitation energies and dissociation energies for the N2 molecule have been compared to corresponding multiReference (MR) CI results. Finally, the dissociation energies for a large number of benchmark molecules containing first-row atoms (the “G1” test) have been compared to experimental data. The computed excitation energies compare very well with the corresponding FCI and MRCI values. In most cases the errors are well below 1 kcal/mol. The dissociation energies, on the other hand, are in general improved in the new treatment but have a tendency to be overestimated when compared to other more accurate methods.
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second order perturbation theory with a complete active space self consistent field Reference Function
Journal of Chemical Physics, 1992Co-Authors: Kerstin Andersson, Perake Malmqvist, Bjorn O RoosAbstract:The recently implemented second‐order perturbation theory based on a complete active space self‐consistent field Reference Function has been extended by allowing the Fock‐type one‐electron operator, which defines the zeroth‐order Hamiltonian to have nonzero elements also in nondiagonal matrix blocks. The computer implementation is now less straightforward and more computer time will be needed in obtaining the second‐order energy. The method is illustrated in a series of calculations on N2, NO, O2, CH3, CH2, and F−.
