Missile acceleration saturation in a practical terminal guidance process may significantly reduce the interception performance.To solve this problem,this paper presents an anti-saturation guidance law with finite-time...Missile acceleration saturation in a practical terminal guidance process may significantly reduce the interception performance.To solve this problem,this paper presents an anti-saturation guidance law with finite-time convergence for a three dimensional maneuvering interception.The finite time boundedness(FTB)theory and the input-output finite time stability(IO-FTS)theory are used,as well as the long short-term memory(LSTM)network.A sufficient condition for FTB and IO-FTS of a class of nonlinear systems is given.Then,an anti-acceleration saturation missile terminal guidance law based on LSTM,namely LSTM-ASGL,is designed.It can effectively suppress the effect of acceleration saturation to track the maneuvering target more accurately in the complex dynamic environment.The excellent performance of LSTM-ASGL in different maneuvering target scenarios is verified by simulation.The simulation results show that the guidance law successfully prevents acceleration saturation and improves the tracking ability of the missile system to the maneuvering target.It is also shown that LSTM-ASGL has good generalization and anti-jamming performance,and consumes less energy than the anti-acceleration saturation terminal guidance law.展开更多
This paper studies the sliding mode controller design problems for a class of nonlinear system. The nonlinear function is considered to satisfy conic-type constraint condition. A novel finite-time boundedness(FTB) bas...This paper studies the sliding mode controller design problems for a class of nonlinear system. The nonlinear function is considered to satisfy conic-type constraint condition. A novel finite-time boundedness(FTB) based sliding mode controller design theory is proposed. And then a sufficient condition is obtained in terms of linear matrix inequalities(LMIs), which guarantees the resulted sliding mode dynamics to be FTB wrt some predefined scalars. Thereafter, a FTB-based sliding mode control(SMC) law is synthesized to ensure the state of the controlled system is driven into a novel desired switching surface s(t) = c(c is a constant) in a finite time. Simulation results illustrate the validity of the proposed FTB-based SMC design theory.展开更多
This article addresses the finite-time boundedness(FTB)problem for nonlinear descriptor systems.Firstly,the nonlinear descriptor system is represented by the Takagi-Sugeno(T-S)model,where fuzzy representation is assum...This article addresses the finite-time boundedness(FTB)problem for nonlinear descriptor systems.Firstly,the nonlinear descriptor system is represented by the Takagi-Sugeno(T-S)model,where fuzzy representation is assumed to be appearing not only in both the state and input matrices but also in the derivative matrix.By using a descriptor redundancy approach,the fuzzy representation in the derivative matrix is reformulated into a linear one.Then,we introduce a fuzzy sliding mode control(FSMC)law,which ensures the finite-time boundedness(FTB)of closed-loop fuzzy control systems over the reaching phase and sliding motion phase.Moreover,by further employing the descriptor redundancy representation,the sufficient condition for designing FSMC law,which ensures the FTB of the closed-loop control systems over the entire finite-time interval,is derived in terms of linear matrix inequalities(LMIs).Finally,a simulation study with control of a photovoltaic(PV)nonlinear system is given to show the effectiveness of the proposed method.展开更多
A method for the preparation and identification of fumitremorgin B-hemisuccinatecarrier protein is described. The overall yield of the fumitremorgin B-hemisuccinate (FTBS) after final purification was 78.6%. The FTBS ...A method for the preparation and identification of fumitremorgin B-hemisuccinatecarrier protein is described. The overall yield of the fumitremorgin B-hemisuccinate (FTBS) after final purification was 78.6%. The FTBS was characterized by UV, IR, EIMS,element analysis, and 1H, 13C NMR. IR was also used to determine the formation of complete antigen complexes. The reaction route was analysized.展开更多
文摘Missile acceleration saturation in a practical terminal guidance process may significantly reduce the interception performance.To solve this problem,this paper presents an anti-saturation guidance law with finite-time convergence for a three dimensional maneuvering interception.The finite time boundedness(FTB)theory and the input-output finite time stability(IO-FTS)theory are used,as well as the long short-term memory(LSTM)network.A sufficient condition for FTB and IO-FTS of a class of nonlinear systems is given.Then,an anti-acceleration saturation missile terminal guidance law based on LSTM,namely LSTM-ASGL,is designed.It can effectively suppress the effect of acceleration saturation to track the maneuvering target more accurately in the complex dynamic environment.The excellent performance of LSTM-ASGL in different maneuvering target scenarios is verified by simulation.The simulation results show that the guidance law successfully prevents acceleration saturation and improves the tracking ability of the missile system to the maneuvering target.It is also shown that LSTM-ASGL has good generalization and anti-jamming performance,and consumes less energy than the anti-acceleration saturation terminal guidance law.
基金supported in part by the National Natural Science Foundation of China(61673001,61203051)the Foundation for Distinguished Young Scholars of Anhui Province(1608085J05)the Key Support Program of University Outstanding Youth Talent of Anhui Province(gxydZD201701)
文摘This paper studies the sliding mode controller design problems for a class of nonlinear system. The nonlinear function is considered to satisfy conic-type constraint condition. A novel finite-time boundedness(FTB) based sliding mode controller design theory is proposed. And then a sufficient condition is obtained in terms of linear matrix inequalities(LMIs), which guarantees the resulted sliding mode dynamics to be FTB wrt some predefined scalars. Thereafter, a FTB-based sliding mode control(SMC) law is synthesized to ensure the state of the controlled system is driven into a novel desired switching surface s(t) = c(c is a constant) in a finite time. Simulation results illustrate the validity of the proposed FTB-based SMC design theory.
基金This work was supported in part by the Central Government Drects Special Funds for Scientific and Technological Development of China(2019L3009)Natural Science Foundation of Fujian Province of China(2020J02045).
文摘This article addresses the finite-time boundedness(FTB)problem for nonlinear descriptor systems.Firstly,the nonlinear descriptor system is represented by the Takagi-Sugeno(T-S)model,where fuzzy representation is assumed to be appearing not only in both the state and input matrices but also in the derivative matrix.By using a descriptor redundancy approach,the fuzzy representation in the derivative matrix is reformulated into a linear one.Then,we introduce a fuzzy sliding mode control(FSMC)law,which ensures the finite-time boundedness(FTB)of closed-loop fuzzy control systems over the reaching phase and sliding motion phase.Moreover,by further employing the descriptor redundancy representation,the sufficient condition for designing FSMC law,which ensures the FTB of the closed-loop control systems over the entire finite-time interval,is derived in terms of linear matrix inequalities(LMIs).Finally,a simulation study with control of a photovoltaic(PV)nonlinear system is given to show the effectiveness of the proposed method.
文摘A method for the preparation and identification of fumitremorgin B-hemisuccinatecarrier protein is described. The overall yield of the fumitremorgin B-hemisuccinate (FTBS) after final purification was 78.6%. The FTBS was characterized by UV, IR, EIMS,element analysis, and 1H, 13C NMR. IR was also used to determine the formation of complete antigen complexes. The reaction route was analysized.