To find a better way to estimate the lift force induced by an interceptor on a high-speed mono-hull ship,a series of high-speed mono-hull ship models are designed and investigated under different conditions.Different ...To find a better way to estimate the lift force induced by an interceptor on a high-speed mono-hull ship,a series of high-speed mono-hull ship models are designed and investigated under different conditions.Different lift forces are obtained by numerical calculations and validated by a model test in a towing tank.The factors that influence the force are the interceptor height,velocity,draft,and deadrise angle.The relationship between each factor and the induced lift force is investigated and obtained.We found that the induced lift mainly depends on the interceptor height and advancing velocity,and is proportional to the square of the interceptor height and velocity.The results also showed that the effects of the draft and deadrise angle are relatively less important,and the relationship between the induced lift and these two factors is generally linear.Based on the results,a formula including the combined effect of all factors used to estimate the lift force induced by the interceptor is developed based on systematic analysis.The proposed formula could be used to estimate the lift force induced by interceptors,especially under high-speed condition.展开更多
A new terminal guidance law is proposed based on a solid propellant pulse engine and an improved proportional navigation method to address the terminal guidance issue for kinetic interceptors.On this basis,the start-s...A new terminal guidance law is proposed based on a solid propellant pulse engine and an improved proportional navigation method to address the terminal guidance issue for kinetic interceptors.On this basis,the start-stop curve of the pulse motor during the terminal guidance process is designed,along with its start-up logic.The effectiveness of the proposed guidance strategy is verified through simulation.展开更多
Lightning interception technology is one of the three core technical systems of regional lightning protection theory.Among them,the omni-directional multi-pulse lightning interceptor(hereinafter referred to as lightni...Lightning interception technology is one of the three core technical systems of regional lightning protection theory.Among them,the omni-directional multi-pulse lightning interceptor(hereinafter referred to as lightning interceptor,the same below)has the ability to attenuate lightning current≥40%and significantly reduce the intensity of the spatial electromagnetic field around the lightning point.In order to explore the attenuation mechanism and effect of lightning interceptor to lightning current,this paper analyzed a lightning stroke process at 16:00 on August 19,2022,and tried to explain the attenuation effect of lightning interceptor to lightning current with the physical parameters of lightning stroke.展开更多
GF-14 satellite is a new generation of sub-meter stereo surveying and mapping satellite in China,carrying dual-line array stereo mapping cameras to achieve 1∶10000 scale topographic mapping without Ground Control Poi...GF-14 satellite is a new generation of sub-meter stereo surveying and mapping satellite in China,carrying dual-line array stereo mapping cameras to achieve 1∶10000 scale topographic mapping without Ground Control Points(GCPs).In fact,space-based high-precision mapping without GCPs is a challenging task that depends on the close cooperation of several payloads and links,of which on-orbit geometric calibration is one of the most critical links.In this paper,the on-orbit geometric calibration of the dual-line array cameras of GF-14 satellite was performed using the control points collected in the high-precision digital calibration field,and the calibration parameters of the dual-line array cameras were solved as a whole by alternate iterations of forward and backward intersection.On this basis,the location accuracy of the stereo images using the calibration parameters was preliminarily evaluated by using several test fields around the world.The evaluation result shows that the direct forward intersection accuracy of GF-14 satellite images without GCPs after on-orbit geometric calibration reaches 2.34 meters(RMS)in plane and 1.97 meters(RMS)in elevation.展开更多
According to gyro application in micro-satellites, a new gyro bias real-time on-orbit calibration technology is presented and it is independent of any other sensors. The approach relies on gyro on-orbit measurements r...According to gyro application in micro-satellites, a new gyro bias real-time on-orbit calibration technology is presented and it is independent of any other sensors. The approach relies on gyro on-orbit measurements restricted by satellite attitude dynamics and estimates the gyro bias generated when the gyro is electrified. Observability of the calibration model is analyzed and applicable conditions of the technology are derived. Simulation results indicate that the calibration algorithm is accurate and robust at gyro sampling rate, and its convergence speed is fast. Within the given attitude dynamics model error, the convergence time is less than 100 s and the convergence accuracy is about 1.0 (°)/h. Calibration performance can meet requirements of spacecraft operations.展开更多
动能拦截弹(kinetic energy interceptor,KEI)主要用于拦截在助推段、上升段以及中段飞行的中远程和洲际弹道导弹,具有高速、高加速的特点。通过文献资料的研究分析和建模仿真,对KEI导弹的总体参数、气动参数、动力参数进行了反设计和研...动能拦截弹(kinetic energy interceptor,KEI)主要用于拦截在助推段、上升段以及中段飞行的中远程和洲际弹道导弹,具有高速、高加速的特点。通过文献资料的研究分析和建模仿真,对KEI导弹的总体参数、气动参数、动力参数进行了反设计和研究,并对KEI导弹的飞行性能和拦截性能进行了仿真,结果表明:KEI导弹能够在约60 s内加速至6 km/s,并对典型目标具备在助推段/上升段拦截弹道导弹的能力,对国内拦截武器的发展和研究具有参考意义。展开更多
An intercept optimization approach of the exo-atmospheric interceptor is proposed by the middle and terminal flight stages. Firstly, the dynamic models of the exo-atmospheric interceptor in middle and terminal flight ...An intercept optimization approach of the exo-atmospheric interceptor is proposed by the middle and terminal flight stages. Firstly, the dynamic models of the exo-atmospheric interceptor in middle and terminal flight stages are constructed ; and the velocity gain midcourse guidance law and the robust variable structure terminal guidance law are designed. Then the optimization parameters and their constraints affecting the intercept performance are determined. The genetic algorithm (GA) with the advantage of global optimization is used to deal with the intercept optimization problem. The performance index of the optimization is composed of the minimum fuel consumption and the minimum miss distance of the interception. Finally, optimization results of GA and the complex algorithm (CA) are compared. Simulation results show that compared with the traditional opti- mization method, GA can converge to the global optimization better in solving the complex constrained nonlinear combinatorial optimization of the exo-atmospheric interceptor, and reduce the fuel consumption and the miss distance.展开更多
基金financially supported by the National Key Research and Development Program of China(Grant No.2021YFC2800700)the National Natural Science Foundation of China(Grant Nos.52171330,52101379,52101380,51679053)+2 种基金the Project of Research and Development Plan in Key Areas of Guangdong Province(Grant No.2020B1111010002)the Foundation of Key Laboratory of Marine Environmental Survey Technology and Application,Ministry of Natural Resources(Grant No.MESTA-2021-B010)the Natural Science Foundation of Guangdong Province,China(Grant No.2021A1515012134)。
文摘To find a better way to estimate the lift force induced by an interceptor on a high-speed mono-hull ship,a series of high-speed mono-hull ship models are designed and investigated under different conditions.Different lift forces are obtained by numerical calculations and validated by a model test in a towing tank.The factors that influence the force are the interceptor height,velocity,draft,and deadrise angle.The relationship between each factor and the induced lift force is investigated and obtained.We found that the induced lift mainly depends on the interceptor height and advancing velocity,and is proportional to the square of the interceptor height and velocity.The results also showed that the effects of the draft and deadrise angle are relatively less important,and the relationship between the induced lift and these two factors is generally linear.Based on the results,a formula including the combined effect of all factors used to estimate the lift force induced by the interceptor is developed based on systematic analysis.The proposed formula could be used to estimate the lift force induced by interceptors,especially under high-speed condition.
基金The National Natural Science Foundation of China(Project No.52102436)The Natural Science Foundation of Shanghai(Project No.23ZR1462700)+3 种基金The National Key Laboratory Open Fund for Strength and Structural Integrity(Project No.ASSIKFJJ202304006)The Shanghai Aerospace Science and Technology Innovation Fund(Project No.SAST2022-031)The National Key Laboratory of Space Intelligent Control(Project No.2023-JCJQ-LB-006-14)The Shanghai Key Laboratory of Spacecraft Mechanism(Project No.YY-F805202210025)。
文摘A new terminal guidance law is proposed based on a solid propellant pulse engine and an improved proportional navigation method to address the terminal guidance issue for kinetic interceptors.On this basis,the start-stop curve of the pulse motor during the terminal guidance process is designed,along with its start-up logic.The effectiveness of the proposed guidance strategy is verified through simulation.
基金Supported by Technology Research and Development Project of Strong Electro-magnetic Pulse Protection(Lightning)of Sea Wind Field in Guangdong Yuedi-an Zhuhai Biqing Bay.
文摘Lightning interception technology is one of the three core technical systems of regional lightning protection theory.Among them,the omni-directional multi-pulse lightning interceptor(hereinafter referred to as lightning interceptor,the same below)has the ability to attenuate lightning current≥40%and significantly reduce the intensity of the spatial electromagnetic field around the lightning point.In order to explore the attenuation mechanism and effect of lightning interceptor to lightning current,this paper analyzed a lightning stroke process at 16:00 on August 19,2022,and tried to explain the attenuation effect of lightning interceptor to lightning current with the physical parameters of lightning stroke.
基金Independent Project of State Key Laboratory of Geo-information Engineering(SKLGIE2022-ZZ-01)The Youth Science Innovation Fund(No.2023-01)。
文摘GF-14 satellite is a new generation of sub-meter stereo surveying and mapping satellite in China,carrying dual-line array stereo mapping cameras to achieve 1∶10000 scale topographic mapping without Ground Control Points(GCPs).In fact,space-based high-precision mapping without GCPs is a challenging task that depends on the close cooperation of several payloads and links,of which on-orbit geometric calibration is one of the most critical links.In this paper,the on-orbit geometric calibration of the dual-line array cameras of GF-14 satellite was performed using the control points collected in the high-precision digital calibration field,and the calibration parameters of the dual-line array cameras were solved as a whole by alternate iterations of forward and backward intersection.On this basis,the location accuracy of the stereo images using the calibration parameters was preliminarily evaluated by using several test fields around the world.The evaluation result shows that the direct forward intersection accuracy of GF-14 satellite images without GCPs after on-orbit geometric calibration reaches 2.34 meters(RMS)in plane and 1.97 meters(RMS)in elevation.
文摘According to gyro application in micro-satellites, a new gyro bias real-time on-orbit calibration technology is presented and it is independent of any other sensors. The approach relies on gyro on-orbit measurements restricted by satellite attitude dynamics and estimates the gyro bias generated when the gyro is electrified. Observability of the calibration model is analyzed and applicable conditions of the technology are derived. Simulation results indicate that the calibration algorithm is accurate and robust at gyro sampling rate, and its convergence speed is fast. Within the given attitude dynamics model error, the convergence time is less than 100 s and the convergence accuracy is about 1.0 (°)/h. Calibration performance can meet requirements of spacecraft operations.
文摘动能拦截弹(kinetic energy interceptor,KEI)主要用于拦截在助推段、上升段以及中段飞行的中远程和洲际弹道导弹,具有高速、高加速的特点。通过文献资料的研究分析和建模仿真,对KEI导弹的总体参数、气动参数、动力参数进行了反设计和研究,并对KEI导弹的飞行性能和拦截性能进行了仿真,结果表明:KEI导弹能够在约60 s内加速至6 km/s,并对典型目标具备在助推段/上升段拦截弹道导弹的能力,对国内拦截武器的发展和研究具有参考意义。
文摘An intercept optimization approach of the exo-atmospheric interceptor is proposed by the middle and terminal flight stages. Firstly, the dynamic models of the exo-atmospheric interceptor in middle and terminal flight stages are constructed ; and the velocity gain midcourse guidance law and the robust variable structure terminal guidance law are designed. Then the optimization parameters and their constraints affecting the intercept performance are determined. The genetic algorithm (GA) with the advantage of global optimization is used to deal with the intercept optimization problem. The performance index of the optimization is composed of the minimum fuel consumption and the minimum miss distance of the interception. Finally, optimization results of GA and the complex algorithm (CA) are compared. Simulation results show that compared with the traditional opti- mization method, GA can converge to the global optimization better in solving the complex constrained nonlinear combinatorial optimization of the exo-atmospheric interceptor, and reduce the fuel consumption and the miss distance.