An impact point prediction(IPP) guidance based on supervised learning is proposed to address the problem of precise guidance for the ballistic missile in high maneuver penetration condition.An accurate ballistic traje...An impact point prediction(IPP) guidance based on supervised learning is proposed to address the problem of precise guidance for the ballistic missile in high maneuver penetration condition.An accurate ballistic trajectory model is applied to generate training samples,and ablation experiments are conducted to determine the mapping relationship between the flight state and the impact point.At the same time,the impact point coordinates are decoupled to improve the prediction accuracy,and the sigmoid activation function is improved to ameliorate the prediction efficiency.Therefore,an IPP neural network model,which solves the contradiction between the accuracy and the speed of the IPP,is established.In view of the performance deviation of the divert control system,the mapping relationship between the guidance parameters and the impact deviation is analysed based on the variational principle.In addition,a fast iterative model of guidance parameters is designed for reference to the Newton iteration method,which solves the nonlinear strong coupling problem of the guidance parameter solution.Monte Carlo simulation results show that the prediction accuracy of the impact point is high,with a 3 σ prediction error of 4.5 m,and the guidance method is robust,with a 3 σ error of 7.5 m.On the STM32F407 singlechip microcomputer,a single IPP takes about 2.374 ms,and a single guidance solution takes about9.936 ms,which has a good real-time performance and a certain engineering application value.展开更多
In this paper,we present an overview of the mechanical design and control of biomimetic robotic fishes with high maneuverability.The robotic fishes modelled after Esoxlucius adopt multilink propulsive mechanism for a ...In this paper,we present an overview of the mechanical design and control of biomimetic robotic fishes with high maneuverability.The robotic fishes modelled after Esoxlucius adopt multilink propulsive mechanism for a high turning rate and a small turning radius.According to different tasks,these robotic fishes are designed with decorated pectoral fins for a two-dimensional horizon plane,or controllable pectoral fins with multiple degrees of freedom for a three-dimensional space.Through observing and analyzing the fast-starts of real fish,we separately develop a dynamic trajectory tracking strategy based C-start control method and an L-shaped sliding method based S-start control method.Finally,a four-link robotic fish is able to execute C-start flexibly with a turning angle of up to 213°,a top turning rate of approximately670°/s,and an upper limit of turning precision of less than 10°and an S-start with a peak turning rate up to318.08±9.20°/s.The experimental results verify the feasibility of our high-maneuverability-oriented mechatronic design and control methods.展开更多
基金supported by the National Natural Science Foundation of China (Grant No.62103432)supported by Young Talent fund of University Association for Science and Technology in Shaanxi, China(Grant No.20210108)。
文摘An impact point prediction(IPP) guidance based on supervised learning is proposed to address the problem of precise guidance for the ballistic missile in high maneuver penetration condition.An accurate ballistic trajectory model is applied to generate training samples,and ablation experiments are conducted to determine the mapping relationship between the flight state and the impact point.At the same time,the impact point coordinates are decoupled to improve the prediction accuracy,and the sigmoid activation function is improved to ameliorate the prediction efficiency.Therefore,an IPP neural network model,which solves the contradiction between the accuracy and the speed of the IPP,is established.In view of the performance deviation of the divert control system,the mapping relationship between the guidance parameters and the impact deviation is analysed based on the variational principle.In addition,a fast iterative model of guidance parameters is designed for reference to the Newton iteration method,which solves the nonlinear strong coupling problem of the guidance parameter solution.Monte Carlo simulation results show that the prediction accuracy of the impact point is high,with a 3 σ prediction error of 4.5 m,and the guidance method is robust,with a 3 σ error of 7.5 m.On the STM32F407 singlechip microcomputer,a single IPP takes about 2.374 ms,and a single guidance solution takes about9.936 ms,which has a good real-time performance and a certain engineering application value.
基金supported by the National Natural Science Foundation of China(Grant Nos.61375102, 61333016 and 61421004)
文摘In this paper,we present an overview of the mechanical design and control of biomimetic robotic fishes with high maneuverability.The robotic fishes modelled after Esoxlucius adopt multilink propulsive mechanism for a high turning rate and a small turning radius.According to different tasks,these robotic fishes are designed with decorated pectoral fins for a two-dimensional horizon plane,or controllable pectoral fins with multiple degrees of freedom for a three-dimensional space.Through observing and analyzing the fast-starts of real fish,we separately develop a dynamic trajectory tracking strategy based C-start control method and an L-shaped sliding method based S-start control method.Finally,a four-link robotic fish is able to execute C-start flexibly with a turning angle of up to 213°,a top turning rate of approximately670°/s,and an upper limit of turning precision of less than 10°and an S-start with a peak turning rate up to318.08±9.20°/s.The experimental results verify the feasibility of our high-maneuverability-oriented mechatronic design and control methods.
